CICA CompendiumE D I T E D B Y S A D I A S A I M A , F A R A H I S L A M A E S H A , M A H I A F A R S U M I S L A M & S A M I A J A H A N

CICA Compendium 2026Edited by Sadia Saima, Farah Islam Aesha Mahia Farsum Islam, and Samia Jahanl

First published 2026 by Community Development for Peace (CDP) Lift 11, Pragati Tower, Pragati Sarani, Merul Badda, Dhaka- 1212 © 2026 selection and editorial matter, Sadia Saima, Farah Islam Aesha, Mahia Farsum Islam and Samia Jahan; individual chapters, the contributors © Community Development for Peace (CDP) All rights reserved. No part of this book may be reprinted or reproduced or utilised in any form or by any electronic, mechanical, or other means, now known or hereafter invented, including photocopying and recording, or in any information storage or retrieval system, without permission in writing from the publishers. Trademark notice : Product or corporate names may be trademarks or registered trademarks, and are used only for identifi cation and explanation without intent to infringe.ll

CICA Compendium 2026Editorial Team Sadia Saima Program Associate Community Development for Peace (CDP) Farah Islam Aesha Research Associate, Community Development for Peace (CDP) Mahia Farsum Islam Research Associate, Community Development for Peace (CDP) Samia Jahan Research Associate, Community Development for Peace (CDP)lll

CONTENTSPreface About Community Development for Peace (CDP) About CICA About Postgraduate Programs in Disaster Management (PPDM) About Brac UniversityV Vl Xl XVl XIXlVEvaluating the Potential of Hatirjheel as a Nature-Based Solution for Urban Environmental Resilience in Dhaka Samia Jahan & Farah Islam Aesha Evaluating Recharge Pakistan as a Nature-Based Solution for Flood Risk Reduction and Climate Resilience in the Indus Basin Seema Gul Case Study of Ramna Park as a viable Nature-based Solution (NbS) Aadib Sharif Examining the problem, the NbS addresses, how it works, its impacts, and its strengths and limitations - A Case Study in Miyawaki Forest, Diabari. Case Study of Sundarbans as a Nature Based Solution (NbS) Project Sonapahar: A Nature-based Solution for Industrial wasteland reclamation and Climate resilience in Chattogram, Bangladesh. Floating Treatment Wetland Systems for Waterlogging and Ecological Restoration of Dhanmondi Lake as a Nature Based Solution (NbS) Nature-Based Solutions (NbS): A Local Case Study of The Norai River as an Unplanned Nature-Based Solution Case Study and Comprehensive Technical Report: Ecosystem Restoration and Nature-Based Solution (NbS) Master Plan for the National Botanical Garden of Bangladesh.1 2

CONTENTSPreface About Community Development for Peace (CDP) About CICA About Postgraduate Programs in Disaster Management (PPDM) About Brac UniversityV Vl Xl XVl XIXlVEvaluating the Potential of Hatirjheel as a Nature-Based Solution for Urban Environmental Resilience in Dhaka Evaluating Recharge Pakistan as a Nature-Based Solution for Flood Risk Reduction and Climate Resilience in the Indus Basin 12 Case Study of Ramna Park as a viable Nature-based Solution (NbS) Examining the problem, the NbS addresses, how it works, its impacts, and its strengths and limitations - A Case Study in Miyawaki Forest, Diabari. Case Study of Sundarbans as a Nature Based Solution (NbS) Project Sonapahar: A Nature-based Solution for Industrial wasteland reclamation and Climate resilience in Chattogram, Bangladesh. Floating Treatment Wetland Systems for Waterlogging and Ecological Restoration of Dhanmondi Lake as a Nature Based Solution (Nbs) Nature-Based Solutions (NbS): A Local Case Study of The Norai River as an Unplanned Nature-Based Solution Case Study and Comprehensive Technical Report: Ecosystem Restoration and Nature-Based Solution (NbS) Master Plan for the National Botanical Garden of Bangladesh. Vetiver Grass Bioshields for Riverbank and Slope Stabilization: A Nature- Based Solution Case Study from Chilmari Upazila, Kurigram District, Bangladesh. Case study of Nikli Haor as a viable Nature Based Solution (NbS)

PREFACEResearch Compendium 2005–2025 has been published with the aim of showcasing the research initiatives undertaken by the students and faculty members of the Department of Disaster Management and Environmental Studies (DMES) at BRAC University. Under the banner of the Postgraduate Programs in Disaster Management (PPDM), the department has been offering its master’s program since 2005. As a requirement of the degree, every master’s student conducts independent research on relevant and contemporary issues. Over the years, the department has received numerous commendable research contributions from its students. In addition, our esteemed faculty members have been actively engaged in independent and funded research projects that reflect their excellence and significant contributions to the diverse fields of disaster management, climate change, and humanitarian response. The valuable outcomes of these research endeavors deserved to be compiled in a book format so that readers can easily access and appreciate the department’s research-intensive academic work. We are proud to present this compilation of abstracts from dissertations, publications, and reports produced over the last two decades. Alongside brief presentations of student and faculty research, this publication also includes concise overviews of the department’s academic programs and messages from key individuals associated with the programs. On behalf of the department, I hope this publication will reach a wider audience and further strengthen our collective pursuit of academic excellence and impactful research. I wish continued success in all our future endeavors.Muhammad Ferdaus Founder & CEO Commmunity Development for Peace (CDP)V

Department of Disaster Management and Environmental Studies (DMES) offers academic programs on developing resilient social and built environment and conserving and restoring natural environment with mitigation measures, adaptation opportunities, risk-reduction technological applications, and humanitarian standards, targeting all kinds of natural and human-induced hazards, environmental degradation, and threats. Vision To prepare tomorrow’s professionals and critical thinkers driven by the development ethos of a responsive, resilient, peaceful, adaptive, and inclusive built and social environment. Mission To create future professionals and leaders with multidisciplinary knowledge and skills aimed at cultivating comprehensive technological, socioeconomic, political, and global understanding to foster an environment that ensures sustainable development of all nations and ethnicities. To produce socially responsible and ethically enriched graduates to serve local and global communities in need. To provide supports for designing resilient social and built environment with mitigation measures, adaptation opportunities, risk-reduction technological applications, and humanitarian standards, targeting all kinds of natural and human-induced hazards, environmental degradation, and threats.ABOUT CDPVl

ABOUT CICAPostgraduate Programs in Disaster Management, PPDM: The PPDM was launched in 2005 as the first academic and research program within the structure of a university in Bangladesh. It was the first such program in the entire South Asian region. It offers post-graduate certificates, diploma, and master’s degree programs on Disaster Management issues in five specialized streams: 1.Disaster Risk Reduction 2.Social Safety and Community-based Adaptation 3.Human Security and Humanitarian Crisis Management 4.Climate Change Adaptation and Sustainable Development 5.Public Policy and Organizational Strategies PPDM offers a 1.Master in Disaster Management [ 36 credits ] 2.Diploma in Disaster Management [ 24 credits ] 3.Disaster Management Certificate Program [ 12 Credits ]Vll

Bachelor of Disaster Management Program, BDM: This 141-credit bachelor's program provides the opportunity to become specialized in any field from three fields: 1.Humanitarian Response 2.Climate Change Study 3.Environmental Risk Reduction Technology Among 141 credits, general education covers 39 credits, program core theory and lab courses cover 27 credits, stream-specific theory and lab courses cover 51 credits, elective theory courses cover 12 credits, elective lab courses cover 3 credits, and rest of the 9 credits are covered by Internship, Capstone project or dissertation or study abroad. These 9 credits are also common for all.ABOUT BRAC UNIVERSITYVlll

ABOUT PPDMCell for Adaptation, Resilience, Security and Humanitarian Assistance (CARSHA): The cell Conduct independent and funded research on relevant issues- resilient built and social environment, climate change policy and adaptation, community vulnerability and resilience, security, emergency management, risk reductions, humanitarian assistance, etc. Establish liaisons and collaborations with national and international organizations Provide advocacy and consultancy services for reviewing and editing documents, preparing academic and training program materials, surveying, field study, data collection and analysis, document preparation, finding suitable personals, etc. Conduct training and certificate programs on relevant issues. Arrange events, like, workshops, conferences, seminars, exhibitions, campaign programs, round-table discussions, etc. Provide support through organizing voluntary and non-voluntary services during national and international emergency conditions. Conduct policy, planning, and design-oriented research in relevant areas OtherslX

Blank

1 Evaluating the Potential of Hatirjheel as a Nature- Based Solution for Urban Environmental Resilience in Dhaka Samia Jahan & Farah Islam AeshaAbstract Rapid urbanization in Dhaka has altered and reduced natural drainage systems and wetlands, contributing to waterlogging, stormwater management problems, wastewater pollution and a shortage of accessible public space. Hatirjheel, a centrally located urban waterbody and surrounding redevelopment area that connects several parts of the city, was developed to address these problems together by combining stormwater retention, wastewater improvement, transport connectivity, public recreation and waterbody restoration. This paper describes Hatirjheel's background and how it functions, and evaluates it against the eight criteria of the IUCN Global Standard for Nature-based Solutions (NbS). Hatirjheel is treated here as an NbS-relevant, NbS-like urban intervention rather than a formally designed NbS. The assessment gave an overall score of 63 out of 147 (43%), which indicates partial adherence to the Standard. The project is strongest in societal challenges (61%) and sustainability and mainstreaming (60%), and weakest in inclusive governance and equity (30%), balancing goals and impacts (33%), biodiversity and ecosystem integrity (38%) and adaptive management (39%). The central finding is that infrastructure combined with a waterbody does not automatically make a strong NbS. A stronger NbS would require clearer biodiversity objectives, meaningful community participation, better management of social and environmental trade-offs, continuous monitoring with adaptive management, and long-term ecological financing. Keywords: Hatirjheel; Nature-Based Solutions; IUCN Global Standard; Urban Water Management; DhakaCommunity Development for Peace (CDP), Bangladesh1Introduction Dhaka's rapid urbanization has led to the loss and alteration of natural drainage systems and wetlands (Dewan & Yamaguchi, 2009; Islam et al., 2010; RAJUK, n.d.). One GIS-based study estimated that Dhaka's water bodies shrank by about a third (32.57%) between 1960 and 2008, with land filling and encroachment identified as the main causes (Islam et al., 2010). As built-up land replaces open and permeable areas, rainwater has fewer places to be stored or absorbed, which creates waterlogging and stormwater management problems. These problems are made worse by wastewater and water pollution, and by a growing need for accessible public spaces in a dense city. Dhaka's urban challenges therefore form a chain: rapid urbanisation leads to the loss of natural drainage and wetlands, which leads to waterlogging and stormwater problems, which is compounded by wastewater and water pollution, and finally creates the need for accessible public spaces. Addressing only one link in this chain is unlikely to be enough, which is why integrated, water-based approaches have attracted attention.

2Hatirjheel Hatirjheel is a centrally located urban waterbody and surrounding redevelopment area in Dhaka, Bangladesh, which connects several parts of the city (RAJUK, n.d.). Its ecosystem is an urban lake and wetland system that includes open water, aquatic habitat, vegetated areas and a connected drainage and water-flow system. The project sought to combine five aims: stormwater retention, wastewater improvement, transport connectivity, public recreation and waterbody restoration. Its main beneficiaries are Dhaka residents, commuters, nearby communities and businesses, and visitors and recreational users. Its main functions are water management, mobility, recreation, public space and environmental functions. Despite these multiple benefits, Hatirjheel does not fully meet the expectations of a well-designed Nature- based Solution. Peer-reviewed studies report that water pollution remains a major problem, and that wastewater and stormwater continue to enter the lake through combined sewer overflows (CSOs), with water quality worsening during the wet season (Atauzzaman & Ali, 2022). Research on the project also reports the forced eviction of large numbers of people from the site (Warner & Wiegel, 2021), and raises concerns about participation and justice. A project that delivers broad public benefits while imposing costs on some communities and leaving the lake's ecology under pressure presents a clear contradiction.Hatirjheel Hatirjheel, is a centrally located urban waterbody and surrounding redevelopment area in Dhaka, Bangladesh, which connects several parts of the city (RAJUK, n.d.). Its ecosystem is an urban lake and wetland system that includes open water, aquatic habitat, vegetated areas and a connected drainage and water-flow system. The project sought to combine five aims: stormwater retention, wastewater improvement, transport connectivity, public recreation and waterbody restoration. Its main beneficiaries are Dhaka residents, commuters, nearby communities and businesses, and visitors and recreational users. Its main functions are water management, mobility, recreation, public space and environmental functions. Despite these multiple benefits, Hatirjheel does not fully meet the expectations of a well-designed Nature- based Solution. Peer-reviewed studies report that water pollution remains a major problem, and that wastewater and stormwater continue to enter the lake through combined sewer overflows (CSOs), with water quality worsening during the wet season (Atauzzaman & Ali, 2022). Research on the project also reports the forced eviction of large numbers of people from the site (Warner & Wiegel, 2021), and raises concerns about participation and justice. A project that delivers broad public benefits while imposing costs on some communities and leaving the lake's ecology under pressure presents a clear contradiction.Our Aim This paper asks to what extent Hatirjheel meets the IUCN Global Standard for Nature-based Solutions (IUCN, 2020). It does not ask only whether Hatirjheel provides benefits, but whether it meets the wider requirements of a well-designed, sustainable, inclusive and adaptive NbS. The paper describes the site, reviews its environmental, social and economic outcomes, presents the results of the IUCN self-assessment across eight criteria, and discusses strengths, limitations and lessons for replication.

3Background and Context Dhaka is a dense and fast-growing capital. Urban expansion has transformed natural drainage paths and wetlands, and the resulting waterlogging and stormwater problems affect transport, property and daily life. A preliminary drainage and lowland study by BUET, referenced in RAJUK's project documentation, formed part of the technical background for the Hatirjheel-Begunbari project (BUET, n.d.; RAJUK, n.d.). At the same time, residents need accessible green and blue public spaces. Nature-based Solutions use the protection, restoration and sustainable management of ecosystems to address societal challenges while delivering benefits for people and biodiversity (Cohen-Shacham et al., 2016; IUCN, 2020). In an urban setting, these challenges include drainage and flood management, water quality and wastewater systems, biodiversity and ecosystem integrity, public open space, climate resilience and equitable access to environmental benefits. Hatirjheel is located in the heart of Dhaka and is part of the Hatirjheel-Begunbari Integrated Development Project led by RAJUK (RAJUK, n.d.). It operates as an integrated urban system that includes the waterbody, drainage, wastewater management, roads, recreation areas and public space. RAJUK's stated objectives were stormwater retention, environmental improvement and transport. Studies of the lake's transport role, including its water-taxi system and urban transport integration, show that it also functions as a mobility corridor. The lake therefore serves several purposes at once: water management, mobility, recreation, public space and environmental functions. Hatirjheel must retain and drain stormwater while receiving polluted inflows from the surrounding city. CSO discharges continue to introduce wastewater and stormwater into the lake, and water quality worsens during the wet season (Atauzzaman & Ali, 2022). Ecological conditions vary across the lake, and persistent pollution, especially around CSO discharge points, continues to degrade water quality and aquatic habitat. The environmental challenge is therefore twofold: to keep delivering drainage and amenity functions, and to protect a degraded urban ecosystem that depends on the wider drainage and wastewater system for its condition.Description of the Nature-Based Solution Nature-based Solutions use ecosystems to address societal challenges while delivering benefits for people and biodiversity, and the IUCN Global Standard offers a framework for verifying, designing and scaling up NbS (IUCN, 2020). Research on urban NbS likewise stresses that such interventions should deliver co- benefits for climate adaptation, water management and well-being, while acknowledging knowledge gaps and barriers to implementation (Kabisch et al., 2016; Seddon et al., 2020). In this paper, Hatirjheel is treated as an NbS-relevant or NbS-like urban intervention and is assessed against the Standard. It combines a natural or restored waterbody with engineered drainage, roads and public-space infrastructure, which makes it a hybrid system. It is important to be clear about its origins. Hatirjheel was originally designed as urban infrastructure, not as a formally defined NbS, and NbS outcomes for people and nature were not clearly defined at the outset (RAJUK, n.d.). Hatirjheel lies in central Dhaka and links several parts of the city. The system includes open water, aquatic habitat, vegetated areas and connected drainage channels, surrounded by a redeveloped urban area with roads, walkways and public spaces. The main beneficiaries are Dhaka residents, commuters, nearby communities and businesses, and visitors and recreational users.

4The Hatirjheel-Begunbari Integrated Development Project was led by RAJUK and sought to combine stormwater retention, wastewater improvement, transport connectivity, public recreation and waterbody restoration (RAJUK, n.d.). The project developed the waterbody as an urban asset and linked it to roads and public space. Development of the project required land acquisition and the relocation of some people. Warner and Wiegel (2021) cite Hatirjheel as a case in which land acquisition for the lake and its beautification led to the forced eviction of tens of thousands of people, and raised concerns about participation and justices. Management arrangements for the lake's ecosystem are less clearly documented, and there is no clear long-term funding mechanism for ecosystem management. Hatirjheel works as follows. Urban rainfall enters the Hatirjheel urban waterbody, which then supports three groups of functions. Under water management, the lake provides water retention and drainage, which reduces waterlogging pressure. Under ecosystem functions, habitat and vegetation provide environmental and recreational benefits. Under transport and mobility, the project provides improved connectivity, mobility and accessibility. The waterbody and drainage functions may offer a potential contribution to climate resilience by providing space for stormwater management. The word "potential" is used deliberately: the available evidence documents the function and purpose of the system, but does not quantify how much flood risk it removes. Hatirjheel is an urban lake and wetland system with open water, aquatic habitat and vegetated areas. A study of aquatic insects recorded species and communities in the lake, with greater diversity in vegetation- rich areas (Islam et al., 2023). Sampling between November 2015 and February 2016 recorded 3,255 individuals from 20 families and five insect orders, with the vegetation-rich section near the Mouchak– Moghbazar flyover recording the highest richness (Islam et al., 2023). This indicates that the lake does support aquatic life and that vegetation matters for biodiversity. However, ecological conditions vary across the lake, and persistent pollution around CSO discharge points degrades water quality and aquatic habitat. Clear and measurable biodiversity targets are not evident. Hatirjheel has become a public recreational space and a landmark and public destination in Dhaka. It improves urban amenity and mobility, and its water-taxi and road links improve connectivity. Residents, commuters and recreational users all benefit. These benefits are among the project's most visible results, although, as discussed in Section 5.5, they have not been shared equally by everyone affected by the project.Evidence and Impacts Observed environmental outcomes include retention of an urban waterbody in a dense city, aquatic habitat, a drainage function and vegetated areas. These outcomes are significant because large urban waterbodies are rare in dense cities. At the same time, the lake's ecological performance is limited by pollution, and biodiversity protection has not been a strong management objective. Peer-reviewed studies document water-quality problems in Hatirjheel and identify CSO discharges as a major source of pollution, with wastewater and stormwater entering the lake and water quality worsening in the wet season (Atauzzaman & Ali, 2022).Monsoon rain dilutes Dhaka's lake pollution while pre-monsoon peaks it, with Hatirjheel moderately polluted and showing elevated TDS and conductivity post-monsoon.

Socially, the project created public recreational space, improved urban amenity, a landmark public destination and mobility benefits. These benefits are broad and benefit many groups of people. However, the project also affected people living and working around the Hatirjheel area. Research reports forced relocation and socioeconomic impacts on project-affected people (South Asia Research study). Affected communities did not have a strong enough role in decision-making. The project therefore created broad public benefits, but some affected people experienced significant social and economic costs through relocation and land acquisition. Observed economic benefits include improved accessibility, connectivity benefits, benefits to surrounding urban activity and increased attractiveness of the surrounding area. Hatirjheel provides several benefits from a single investment: flood and drainage function, environmental improvement, transport connectivity, recreation and public space. There are limits to this evidence. There is limited comparison with alternative solutions, and no clear long-term funding mechanism for ecosystem management. The economic and financial case for Hatirjheel as an NbS is therefore not fully demonstrated. In terms of disaster risk, Hatirjheel addresses a real and important urban challenge, flooding and water management in Dhaka. By providing space for stormwater storage and drainage, it may reduce waterlogging pressure and contribute to climate resilience. It also supports sustainable development by combining water management, sustainable cities, public well-being and ecosystem functions. The system also depends on the wider drainage and wastewater network. When that network discharges polluted water into the lake, the ecosystem and its resilience functions are weakened. Resilience benefits are therefore real but conditional. Scientific studies monitor water quality, pollution, aquatic biodiversity and ecological conditions in Hatirjheel. Research is being produced, but there is limited evidence of a formal cycle of monitoring, learning, changing management and monitoring again. Hatirjheel has monitoring and research, but these findings are not clearly linked to a continuous management and decision-making system. This is the main reason for the low adaptive-management score in Section 5.7.5IUCN NbS Self-AssessmentFigure 1: Hatirjheel IUCN Global Standard results by criterion (%)

6The assessment used the IUCN Global Standard for Nature-based Solutions, which consists of eight criteria and 28 indicators. An evidence-based assessment of each indicator produces a score for each criterion and an overall performance score. Scores are banded as Strong (80–100%), Adequate (60–79%), Partial (40– 59%) and Insufficient (0–39%). Hatirjheel scored 63 out of 147, or 43%, which means that the intervention does not yet fully adhere to the IUCN Global Standard for NbS. It is strong in problem recognition and long- term visibility, but weak in inclusive governance and adaptive safeguards. Criterion scores range from 30% to 61%, and the overall performance appears fairly balanced, although the weaknesses are important for long-term sustainability. Figure 1 summarises the results and the full score table is given in the Appendix.Societal Challenges Societal challenges scored 61% (Adequate), the highest score. Hatirjheel was developed to improve stormwater retention and drainage, and it also aimed to address wastewater problems, traffic congestion and the lack of public space. These problems and the project's objectives are clearly documented. Major urban problems were identified (flooding, drainage, wastewater and traffic) and multiple problems were addressed together through one project, with RAJUK's objectives being stormwater retention, environmental improvement and transport (RAJUK, n.d.). The main limitation is that Hatirjheel was originally designed as urban infrastructure, not as a formally defined NbS, and NbS outcomes for people and nature were not clearly defined. Problem identification is strong but NbS-specific outcomes are less clearly defined.Integrated Systems Perspective Integrated systems perspective scored 50% (Partial). Hatirjheel combines a waterbody, drainage, wastewater, roads, recreation and public space, so the project clearly works across several sectors and operates as one integrated urban system with multiple functions: water management, transport, environmental improvement and recreation. The key limitation is that it depends on the wider drainage and wastewater system. CSO discharges continue to introduce wastewater and stormwater into the lake, and water quality worsens during the wet season. Multiple sectors are connected, but wider urban water-system interactions need stronger management.Enhanced Biodiversity and Ecosystem Integrity Biodiversity and ecosystem integrity scored 38% (Insufficient). On the positive side, Hatirjheel provides aquatic habitat, and a study recorded aquatic insect species and communities with greater diversity in vegetation-rich areas. On the negative side, water pollution remains a major problem, wastewater enters through CSOs, ecological conditions vary across the lake, and clear measurable biodiversity targets are not evident. Hatirjheel has ecological value, but persistent pollution, especially around CSO discharge points, continues to degrade water quality and aquatic habitat. Biodiversity protection is not a strong management objective and pollution remains a major ecological pressure.Financial Feasibility and Economic Justification Financial feasibility and economic justification scored 40% (Partial). The strength of the project is that several benefits are delivered from one investment: flood and drainage function, environmental improvement, transport connectivity, recreation and public space.

7The gaps are that there are many public benefits but limited evidence of comparison with alternative solutions, and there is no clear long-term funding mechanism for ecosystem management. Full NbS cost- effectiveness is therefore not demonstrated, and long-term ecological financing needs strengthening.Inclusive Governance and Equity Inclusive governance and equity scored 30% (Insufficient), the lowest score. Inclusive participation is the biggest gap. The project affected different groups, including people living and working around the Hatirjheel area, and research reports that land acquisition for the project led to the forced eviction of large numbers of people (Warner & Wiegel, 2021). The urban NbS literature stresses that inclusive governance and the fair distribution of costs and benefits are central to NbS success (Cohen-Shacham et al., 2019; Frantzeskaki, 2019). Hatirjheel scores lowest here because affected communities did not have a strong enough role in the project decision-making process. More importantly, the project created broad public benefits, but some affected people experienced significant social and economic costs through relocation and land acquisition. Participation was limited and the impacts of the project were unequally distributed, so stronger community involvement was needed.Balancing Goals and Impacts Balancing goals and impacts scored 33% (Insufficient). The positive impacts were flood management, public space, recreation, transport improvement and urban environmental improvement. The negative impacts were the relocation of affected people, land acquisition impacts, continuing water pollution and pressure on ecosystem health. The key gap is that benefits were not sufficiently balanced with social and environmental safeguards. The project achieved multiple benefits, but the trade-offs were not adequately managed.Adaptive Management Adaptive management scored 39% (Insufficient). Scientific studies monitor water quality, pollution, aquatic biodiversity and ecological conditions. However, there is limited evidence of a formal cycle of monitor, learn, change and monitor again. For example, water-quality problems have been documented, but there is limited evidence of a formal adaptive system that regularly uses monitoring results to change lake management. Hatirjheel has monitoring and research, but these findings are not clearly linked to a continuous management and decision-making system.Enhancing Sustainability and Mainstreaming Sustainability and mainstreaming scored 60% (Adequate), the second-highest score. Hatirjheel demonstrates that one urban waterbody can provide several functions: water management, public space, recreation, transport and environmental benefit. The intervention has also generated considerable technical and academic learning about urban water management and ecosystem conditions. It scores relatively well because it shows how urban water systems can provide multiple benefits and offers useful lessons for future urban planning. However, its lessons should be improved before replication, especially regarding biodiversity, participation, safeguards and long-term monitoring. Overall, the strongest aspects are problem identification and demonstration value, while the weakest are inclusive governance, balancing goals and impacts, and adaptive management.

8Strengths, Limitations and Challenges The major strengths on one hand are that Hatirjheel addresses water management, mobility, recreation and urban environmental needs within a single project. It provides an important ecosystem component within a dense city, where such space is scarce. It benefits residents, commuters and recreational users, and it has become a well-known landmark and public destination. It provides lessons for integrating urban water systems into city planning, and it has generated considerable technical and academic learning (IUCN, 2020). The challenges on the other hand are a lot too. Wastewater and polluted inflows, in particular CSO discharges, continue to affect water quality, and conditions worsen during the wet season. Ecological outcomes and measurable biodiversity targets are limited, so biodiversity has not been a central management objective. Project-affected communities were not sufficiently involved in decision-making. Some communities experienced relocation and socioeconomic impacts, and these were not adequately addressed. Monitoring exists, but its connection to management decisions is limited. There is no clear long- term funding mechanism for ecosystem management, and little comparison with alternative solutions.Conclusion Hatirjheel demonstrates the potential of urban water-based approaches to deliver multiple benefits, including stormwater retention, mobility, recreation, public space and environmental improvement. With an overall IUCN score of 63 out of 147 (43%), however, it does not yet fully adhere to the IUCN Global Standard for Nature-based Solutions. It is best understood as an NbS-relevant urban intervention that was designed as infrastructure rather than as a formally defined NbS. The assessment shows that infrastructure plus a waterbody does not automatically make a strong NbS. A stronger NbS would require stronger biodiversity objectives, meaningful community participation, better management of social and environmental trade-offs, continuous monitoring and adaptive management, and long-term ecological financing. The Hatirjheel experience can still inform future urban water projects in Bangladesh, provided that ecological restoration, social safeguards, participation and adaptive management are integrated from the beginning.References Alam, H. E., Ahmed, K. T., Uddin, M. N., Hasan, M. J., & Arafat, M. Y. (2025). Water quality patterns across seasons in major urban lakes of Dhaka Metropolitan City. Explora: Environment and Resource, 2(4), Article 025310057. https://doi.org/10.36922/EER025310057 Atauzzaman, M., & Ali, M. A. (2022). Effects of combined sewer overflow on water quality: A case study of Hatirjheel Lake in Dhaka. SN Applied Sciences, 4, Article 303. https://doi.org/10.1007/s42452-022-05187-6 BUET. (n.d.). Preliminary drainage and lowland study (as referenced in RAJUK project documentation). Bangladesh University of Engineering and Technology. Cohen-Shacham, E., Andrade, A., Dalton, J., Dudley, N., Jones, M., Kumar, C., Maginnis, S., Maynard, S., Nelson, C. R., Renaud, F. G., Welling, R., & Walters, G. (2019). Core principles for successfully implementing and upscaling Nature-based Solutions. Environmental Science & Policy, 98, 20–29. https://doi.org/10.1016/j.envsci.2019.04.014

Dewan, A. M., & Yamaguchi, Y. (2009). Land use and land cover change in Greater Dhaka, Bangladesh: Using remote sensing to promote sustainable urbanization. Applied Geography, 29(3), 390–401. https://doi.org/10.1016/j.apgeog.2008.12.005 Frantzeskaki, N. (2019). Seven lessons for planning nature-based solutions in cities. Environmental Science & Policy, 93, 101–111. https://doi.org/10.1016/j.envsci.2018.12.033 IUCN. (2020). IUCN Global Standard for Nature-based Solutions: A user-friendly framework for the verification, design and scaling up of NbS (1st ed.). International Union for Conservation of Nature. https://doi.org/10.2305/IUCN.CH.2020.08.en Islam, M. A., Ahmmed, S., Alim, M. A., & Zohora, F. T. (2023). Diversity and abundance of aquatic insect fauna in an urban freshwater lake, Hatirjheel, Dhaka, Bangladesh. Bangladesh Journal of Zoology, 50(3), 363–372. https://doi.org/10.3329/bjz.v50i3.65542 Islam, M. S., Rahman, M. R., Shahabuddin, A. K. M., & Ahmed, R. (2010). Changes in wetlands in Dhaka City: Trends and physico-environmental consequences. Journal of Life and Earth Science, 5, 37–42. https://doi.org/10.3329/jles.v5i0.7348 Kabisch, N., Frantzeskaki, N., Pauleit, S., Naumann, S., Davis, M., Artmann, M., Haase, D., Knapp, S., Korn, H., Stadler, J., Zaunberger, K., & Bonn, A. (2016). Nature-based solutions to climate change mitigation and adaptation in urban areas: Perspectives on indicators, knowledge gaps, barriers, and opportunities for action. Ecology and Society, 21(2), Article 39. https://doi.org/10.5751/ES-08373-210239 RAJUK. (n.d.). Hatirjheel-Begunbari Integrated Development Project documentation. Rajdhani Unnayan Kartripakkha. Raymond, C. M., Frantzeskaki, N., Kabisch, N., Berry, P., Breil, M., Nita, M. R., Geneletti, D., & Calfapietra, C. (2017). A framework for assessing and implementing the co-benefits of nature-based solutions in urban areas. Environmental Science & Policy, 77, 15–24. https://doi.org/10.1016/j.envsci.2017.07.008 Seddon, N., Chausson, A., Berry, P., Girardin, C. A. J., Smith, A., & Turner, B. (2020). Understanding the value and limits of nature-based solutions to climate change and other global challenges. Philosophical Transactions of the Royal Society B, 375(1794), 20190120. https://doi.org/10.1098/rstb.2019.0120 Warner, J. F., & Wiegel, H. (2021). Displacement induced by climate change adaptation: The case of ‘climate buffer’ infrastructure. Sustainability, 13(16), 9160. https://doi.org/10.3390/su131691609

2 Evaluating Recharge Pakistan as a Nature-Based Solution for Flood Risk Reduction and Climate Resilience in the Indus Basin Seema GulAbstract Pakistan is exposed to severe floods, drought and water scarcity, together with soil degradation and ecosystem loss. The floods of August 2022 showed how widespread the damage can be, with large areas of flood water and houses damaged or destroyed across several provinces. Recharge Pakistan is a seven-year project, financed mainly by the Green Climate Fund (USD 66 million) with co-finance from WWF (USD 1.8 million) and The Coca-Cola Foundation (USD 5 million), that applies ecosystem-based adaptation and green infrastructure at six sites in the Indus basin, including DI Khan, Ramak, Chakar Lehri and Manchar. This paper describes the context and design of the project and examines its reported impacts. These include a reduction of 50,833 hectares in area under flood extent, 1,600 million litres of soil infiltration and groundwater replenishment, 20 million cubic metres of water storage, and estimated greenhouse gas reductions of 26,450 tCO2 over the project period and 1,037,928 tCO2 over 40 years. It then reviews the project against the eight criteria of the IUCN Global Standard for Nature-based Solutions. Because the presentation does not include a formal IUCN self-assessment score, the assessment in this paper is a qualitative judgement made by the authors from the evidence presented. The paper finds that Recharge Pakistan is a clear example of an integrated, designed NbS, strongest in problem identification, systems thinking and replication potential. Evidence on participation, trade-off management and adaptive management is less detailed. Long-term maintenance, sustained funding and institutional coordination will determine whether its benefits last. Keywords: Recharge Pakistan; Nature-Based Solutions; Ecosystem-based Adaptation; Green Infrastructure; Indus Basin; Climate ResilienceMinistry of Climate Change & Environmental Coordination, PakistanIntroduction Pakistan faces a combination of local environmental, climate and societal challenges. Flooding destroys homes, land and livelihoods; in other seasons and places, drought and water shortage leave communities dependent on scarce and unreliable water supplies. Soil degradation reduces the productivity of land, and ecosystems and wildlife, including mountain species such as the snow leopard, are under pressure from climate change (Ministry of Climate Change and Environmental Coordination [MoCC&EC], n.d.). These problems are connected. Degraded landscapes absorb less rainfall, so water runs off quickly and causes floods, while less water soaks into the ground to replenish aquifers, which increases water scarcity in dry periods. Solving them separately would be costly and often ineffective, which is why integrated, ecosystem-based approaches are important.10

11Recharge Pakistan Recharge Pakistan is a nature-based programme for climate resilience that works at six sites in the Indus basin, including DI Khan, Ramak, Chakar Lehri and Manchar (WWF-Pakistan, n.d.). It uses ecosystem-based adaptation (EbA) and green infrastructure (GI) to reduce flood risk and improve water retention and groundwater recharge. Its vision is that, by 2050, ecosystem-based adaptation contributes towards better climate resilience, water and food security, and sustainable livelihoods in Pakistan. The project runs for seven years and is financed by the Green Climate Fund (GCF) with co- finance from WWF and The Coca-Cola Foundation. By 2030 it aims to reduce flood risk and enhance water recharge at six sites in the Indus basin, building the resilience of 10 million people and vulnerable ecosystems (GCF, n.d.).Aim This paper aims to assess Recharge Pakistan as a Nature-based Solution for flood risk reduction, water security and climate resilience. It describes the project's context, design and reported impacts, and evaluates it against the eight criteria of the IUCN Global Standard for Nature-based Solutions (IUCN, 2020). It then discusses strengths, limitations and the potential to replicate and scale up the approach in other climate-vulnerable areas of Pakistan.Background and Context Pakistan's population and agriculture depend heavily on the Indus basin. The basin is vulnerable to intense flooding as well as to prolonged dry periods, and both are projected to be affected by climate change. In August 2022, flood water covered extensive areas of the country, and the damage to housing was concentrated in the south and west, with some districts reporting between 50,000 and 130,000 houses damaged or destroyed (UNOCHA, 2022; WWF-Pakistan, n.d.). The Recharge Pakistan sites were chosen within this flood-affected landscape. The project's map shows the implementation sites in the DI Khan-Ramak watershed in Khyber Pakhtunkhwa and the Manchar-Chakkar Lehri watershed in Sindh and Balochistan, overlaid on the August 2022 flood extent.Table 1: Recharge Pakistan at a glance (GCF, n.d.; WWF-Pakistan, n.d.)

12The Environmental Challenge The environmental challenge is to reduce flood damage while also improving water availability. This means slowing and spreading flood water, storing it, and encouraging it to infiltrate so that groundwater is replenished. At the same time, degraded landscapes, flow paths and water channels must be restored so that they can hold soil and water. Solving the challenge requires work at watershed scale rather than at the scale of a single village or structure.Description of the Nature-Based Solution Nature-based Solutions use the protection, restoration and sustainable management of ecosystems to address societal challenges while delivering benefits for people and biodiversity (IUCN, 2020). Recharge Pakistan fits this definition directly, as it was designed from the start as an ecosystem-based adaptation program. It is a hybrid solution, because it combines ecosystem restoration (EbA) with built green infrastructure such as embankments, gabion structures, retention areas and recharge basins. The project operates in the Indus basin, in two main implementation areas: the DI Khan-Ramak watershed and the Manchar-Chakkar Lehri watershed (WWF-Pakistan, n.d.). These are flood-prone, climate-vulnerable landscapes where degraded soils, damaged flow paths and limited water retention increase flood and drought risk. The project is financed principally by the Green Climate Fund under funding proposal FP207, with co- finance from WWF and The Coca-Cola Foundation, making a total of about USD 72.8 million (GCF, n.d.). WWF-Pakistan and the Ministry of Climate Change and Environmental Coordination are the main institutional partners named in the project documentation (MoCC&EC, n.d.; WWF-Pakistan, n.d.). The project runs for seven years, and its vision looks ahead to 2050.Figure 2: Green infrastructure interventions under Recharge Pakistan (WWF-Pakistan, n.d.)The project works on two levels. Ecosystem-based adaptation includes restoration of approximately 12,000 hectares of degraded landscapes and rehabilitation of approximately 35 kilometers of degraded flow paths and water channels. Green infrastructure includes 127 interventions for flood risk reduction: 9 flood protection embankments, 7 flood dispersal embankments, 45 gabion structures, 42 small retention areas, 9 large retention areas and 15 recharge basins (Figure 2). Together these measures slow runoff, disperse and store flood water, and allow water to infiltrate the ground. Embankments protect and redirect flows, gabions stabilise channels and slopes, retention areas hold water, and recharge basins increase groundwater replenishment.

13The project restores wetlands, watersheds and floodplains, and aims to restore ecosystems and biodiversity as well as to reduce risk (MoCC&EC, n.d.). Restoring vegetation and flow paths helps to rebuild soil, regulate water and provide habitat. Recharging groundwater supports ecosystems that depend on it during dry periods. Around 1 million people are expected to benefit directly and around 10 million indirectly (GCF, n.d.). Benefits include reduced flood risk, improved water availability through groundwater recharge, and stronger livelihoods and community resilience. The project also supports Pakistan's climate adaptation goals and the Sustainable Development Goals.Evidence and Impacts The project reports four headline environmental outcomes (Table 2). The area under flood extent is reduced by 50,833 hectares. Watershed management is expected to increase soil infiltration and groundwater replenishment by 1,600 million liters. The ecosystem-based adaptation and green infrastructure interventions provide a water storage and retention capacity of 20 million cubic meters. Estimated greenhouse gas emission reductions are 26,450 tCO2 over the seven-year project and 1,037,928 tCO2 over 40 years.Table 2: Reported overall impact of Recharge Pakistan (WWF-Pakistan, n.d.)The main hydrological benefits are improved water retention and groundwater recharge, and reduced flood and drought risk. Retention areas and recharge basins capture water during floods and make it available later, so the same infrastructure addresses both extremes. Specific water-quality indicators are not given in the presentation. Socially, the project strengthens community resilience and livelihoods, and its community-based approach is a key feature of the model (MoCC&EC, n.d.). Reduced flood damage protects homes and assets, while better water availability supports agriculture and household water needs. Detailed evidence of how communities were involved and how benefits are shared is not given in the presentation. The project is described as nature-based and cost-effective. Securing about USD 72.8 million from public and private sources demonstrates financial confidence in the approach, and the benefits reach around 10 million people indirectly. Avoided flood losses and improved water security for agriculture are likely to be the main economic returns, although the presentation does not quantify them.

14Recharge Pakistan addresses flood hazard directly by reducing flood extent, dispersing flows and storing water. It reduces drought risk by recharging groundwater, and it builds exposure-reducing resilience by restoring the landscape on which communities depend. It supports climate adaptation and the SDGs, and contributes to climate mitigation. The combination of flood and drought benefits is its main resilience advantage. The project reports quantified indicators, such as hectares, litres, cubic metres and tonnes of CO2, which provide a basis for monitoring (GCF, n.d.). To confirm success, these indicators should be tracked after implementation and compared with the baseline, and should include social and biodiversity indicators as well as physical ones. Sustained monitoring is also identified as a requirement in the project's list of challenges.IUCN NbS Self-Assessment The IUCN Global Standard for Nature-based Solutions has eight criteria. The presentation for Recharge Pakistan does not contain a formal scored self-assessment. The ratings below are therefore a qualitative judgement made by the authors from the evidence presented, using the IUCN bands of Strong, Adequate, Partial and Insufficient. They are indicative, and no numerical scores are claimed. A formal assessment would need project documents, such as the GCF funding proposal FP207, to score each of the 28 indicators.Table 3: Indicative qualitative assessment of Recharge Pakistan against the IUCN Global Standard

15Societal Challenges Indicative rating: Strong. The project responds to clearly identified societal challenges: flooding, drought and water scarcity, soil degradation and loss of ecosystems and biodiversity. The August 2022 floods provide a documented example of the scale of the problem, and the project's targets (flood risk reduction and water recharge at six sites, building the resilience of 10 million people) are directly linked to these challenges (GCF, n.d.).Integrated Systems Perspective Indicative rating: Strong. The project works at watershed scale and combines landscape restoration, rehabilitation of flow paths and water channels, and built green infrastructure. It treats flood, drought, ecosystem health and livelihoods as linked, and it operates across several sites in the Indus basin. Strong institutional coordination is still needed to link the project with wider water-management planning. Enhanced Biodiversity and Ecosystem Integrity Indicative rating: Adequate. Restoring about 12,000 hectares of degraded landscape and 35 kilometres of flow paths, and restoring wetlands, watersheds and floodplains, should improve ecosystem integrity. The presentation, however, does not give measurable biodiversity targets or species-level indicators, so the biodiversity outcome cannot yet be verified. Financial Feasibility and Economic Justification Indicative rating: Adequate. The project has secured about USD 72.8 million from the GCF, WWF and The Coca-Cola Foundation, and is described as cost-effective. The main risk is that benefits require time and long-term maintenance, and that sustained funding and monitoring are needed after the seven-year project period. A clear plan for long-term maintenance financing would strengthen this criterion. Inclusive Governance and Equity Indicative rating: Partial. The project is described as community-based, and its beneficiaries are numerous. The presentation does not describe how communities, including women and marginalised groups, take part in decisions, or how grievances are handled. Land-use conflicts may arise, and strong community coordination is listed as a requirement. This criterion should be verified from project documents. Balancing Goals and Impacts Indicative rating: Partial. The project delivers several benefits at once: flood protection, groundwater recharge, ecosystem restoration and carbon benefits. It acknowledges that land-use conflicts may arise. The presentation does not show how trade-offs, for example between embankments, grazing or farming land and ecosystem restoration, are identified and managed. Adaptive Management Indicative rating: Partial. Quantified indicators support monitoring, and the project recognises that effectiveness can be affected by climate extremes and that sustained monitoring is required. A formal cycle of monitoring, learning, adjusting and monitoring again is not described, and should be put in place to keep structures and restored landscapes working under changing conditions.

16Enhancing Sustainability and Mainstreaming Indicative rating: Adequate. The community-based, ecosystem-focused approach is considered suitable for replication in other climate-vulnerable areas of Pakistan. It can be scaled up through stronger institutional coordination, sustainable financing, and integration into national and provincial climate and water- management plans. These steps are proposed rather than yet achieved.Strengths and Limitations Strengths are that the project uses ecosystems and simple green infrastructure, such as gabions and retention areas, rather than relying only on costly grey infrastructure. Improves water retention and groundwater recharge by Retention areas, recharge basins and watershed management store water and increase groundwater replenishment by 1,600 million liters. The project reduces the area under flood extent by 50,833 hectares and stores 20 million cubic meters of water, helping in both wet and dry periods. Restores ecosystems and biodiversity for example 12,000 hectares of degraded landscape and 35 kilometers of flow paths are being restored. Around 1 million people benefit directly and around 10 million indirectly. The project contributes to adaptation, and also to mitigation through estimated emission reductions of 1,037,928 tCO2 over 40 years. Limitations are that the benefits require time and long-term maintenance. Restored landscapes and structures take years to reach full effect and must be maintained. Land-use conflicts may arise for example Embankments, retention areas and restoration compete with farming, grazing and settlement. It requires strong institutional and community coordination because the model depends on cooperation across agencies, provinces and communities. The projects’ effectiveness can be affected by climate extremes like very large floods or prolonged drought can exceed the design capacity of structures and stress restored ecosystems. It requires sustained funding and monitoring: Funding must continue beyond the seven-year project period for maintenance and monitoring. Lastly there is limited public evidence on some criteria such as evidence on participation, trade-offs and biodiversity outcomes is not detailed in the presentation, which limits verification against the IUCN Global Standard.Conclusion Recharge Pakistan provides an integrated nature-based approach to flooding, water scarcity, ecosystem degradation and climate vulnerability. By restoring wetlands, watersheds and floodplains and combining them with green infrastructure, it strengthens ecosystem services while improving community and climate resilience. Its reported outcomes, including a 50,833-hectare reduction in flood extent, 1,600 million litres of groundwater recharge and 20 million cubic metres of storage, show the scale of benefit that a well- designed NbS can deliver. Compared with urban water projects that were designed as infrastructure, Recharge Pakistan was planned as a nature-based programme from the beginning, which gives it a strong starting position against the IUCN Global Standard. Our indicative assessment rates it strongest on societal challenges and integrated systems, adequate on biodiversity, finance and mainstreaming, and partial on inclusive governance, balancing goals and adaptive management, mainly because the available evidence on these is limited. The community-based and ecosystem-focused approach makes the project suitable for replication in other climate-vulnerable areas of Pakistan. It can be scaled up through stronger institutional coordination, sustainable financing, and integration into national and provincial climate and water- management plans. Whether its benefits last will depend on long-term maintenance, sustained funding, continuous monitoring and meaningful community participation.

17References GCF. (n.d.). Recharge Pakistan: Building climate resilience in the Indus basin through ecosystem-based adaptation and green infrastructure (Funding proposal FP207). Green Climate Fund. IUCN. (2020). IUCN Global Standard for Nature-based Solutions: A user-friendly framework for the verification, design and scaling up of NbS (1st ed.). International Union for Conservation of Nature. https://doi.org/10.2305/IUCN.CH.2020.08.en Ministry of Climate Change and Environmental Coordination. (n.d.). Recharge Pakistan project materials. Government of Pakistan. UNOCHA. (2022). Houses damaged and destroyed, Pakistan floods, August 2022 (as shown in the WWF project map). United Nations Office for the Coordination of Humanitarian Affairs. WWF-Pakistan. (n.d.). Recharge Pakistan project sites, flood extent and implementation data. World Wide Fund for Nature – Pakistan.

3 Case Study of Ramna Park as a viable Nature-based Solution (NbS) Aadib Sharif Amin, Debojit Baishya, Ariyan MirjaAbstract Rapid City growth has reduced Dhaka's green areas, air quality, and natural temperature control, making the city very vulnerable to heat, flooding, and loss of wildlife. This paper looks at Ramna Park, a 68.5-acre historic city park in the middle of Dhaka, as a Nature-Based Solution (NbS) to these combined environmental problems. Using studies, official reports, and academic work, it reviews the park's location and history, design, and real-world evidence of its environmental, social, and economic effects. It then evaluates the park using the IUCN Global Standard for Nature-based Solutions Self-Assessment Tool. The assessment gave a score of 69 out of 147 (47%), showing partial compliance with the Global Standard. Ramna Park does well on direct environmental and social results like measurable cooling in the city, high visitor satisfaction, and financial stability but scores poorly on system-wide integration and, most notably, gets a 0% score on inclusive governance. According to these results Ramna Park works as a natural asset passed down than as a carefully managed NbS, though its design is worth copying if future growth fixes the governance and fairness issues the park has not solved. Keywords: Nature-based Solutions, urban green space, Ramna Park, climate resilience, inclusive governanceIntroduction The rapid growth of cities has disrupted Dhaka's natural environments; temperature, air quality, and drainage have worsened, while wildlife and open spaces have shrunk quickly. In the 1960s, 80% of the city was covered with plants, wetlands, and open areas, but by 2005 only about a quarter remained. By 2020 “less than half of the foliage three decades ago still exists” (Anjum et al., 2024; Khan et al., 2023). These changes affect many systems one after another. Dhaka’s Wet Bulb Globe Temperature often goes above safe levels for outdoor workers (Kamruzzaman et al., 2026); there is no ground left to soak up rain, which harms the drainage system; and without natural homes, city wildlife is forced out. Ramna Park, a roughly 68.5-acre green space at the geographic and historical center of Dhaka, is one of the few remaining sites capable of simultaneously counteracting several of the mentioned issues meaningfully. Originally planned as a Mughal-era Garden in the early seventeenth century and redeveloped repeatedly under British colonial administration, the park we see today is managed by the Government of Bangladesh's Public Works Department (PWD) and functions less as a preserved historical curiosity and more as active urban infrastructure dedicated towards cooling its surroundings, filtering pollutants, and sustaining measurable biodiversity.18Department of Disaster Management and Environmental Studies, Brac University, Bangladesh

19This paper examines Ramna Park as a Nature-Based Solution (NbS) to Dhaka's overlapping environmental and disaster-risk challenges. It establishes the geographic, historical, and policy context in which the park operates; elaborating on its physical design and ecological composition, along with reviewing the empirical evidence for its environmental, social, and economic impacts and formally evaluating it against the IUCN Global Standard for Nature-based Solutions Self-Assessment Tool. The resulting assessment score of 69 out of 147 (47%) indicates that Ramna Park, despite genuine and measurable environmental performance, does not fully adhere to the international standard for a well- designed NbS, primarily due to significant institutional and governance shortcomings in design and implementation. The paper concludes by weighing the park's strengths and weaknesses and considering what would be required for it to be more fully replicated or scaled elsewhere in DhakaFigure 3: Map of Ramna Park (Jahan et al., 2024)Background and Context Ramna Park sits at the intersection of the academic, administrative, and residential core of Dhaka, bordered on nearly every side by major arterial roads; Shahbagh Road, Kazi Nazrul Islam Avenue, Captain Monsur Ali Sarani, Hare Road, Nawab Abdul Gani Sharani, and College Road (Pasha et al., 2021). The Park currently covers approximately 68.5 acres, down from the initial 88.5 acres from 1949, the 20 acres having been absorbed by surrounding institutional and commercial infrastructure over the last seven decades (Pasha et al., 2021). Its origins trace to roughly 1610 CE, when the Mughal administrator Islam Khan first developed the area as a pleasure garden; later cleared and formalized under British magistrates as Dhaka's first racecourse in the 1820s-1840s. Finally, it was redesigned in 1908 by R. L. Proudlock of London's Kew Botanical Gardens into the landscape that exists today (Pasha et al., 2021). Physically, the park sits within the Ganges-Brahmaputra-Meghna (GBM) delta, 1.5 to 13 meters above sea level. Built on Pleistocene Madhupur clay overlying the Dupi Tila sand aquifer (Pasha et al., 2021), its central feature is an 8.76-acre lake which anchors both the park's ecology and its recreational design (Pasha et al., 2021; Razzak et al., 2013). Roughly 812 meters long and averaging 2.5 meters deep, the lake's natural sub-surface drainage has started being restricted due to High-rise construction along the park's eastern boundaries, which contributes to a gradual decline in the surrounding groundwater table (Pasha et al., 2021).

20Dhaka is deteriorating in many ways because its natural systems are damaged by fast city growth. Ramna Park is important as a natural solution because it can help reduce these problems. Dhaka's green coverage has gone down from roughly 80% of land cover in the 1960s to 25% by 2005, and further losing 56% of green space by 2020 (Khan et al., 2023; Anjum et al., 2024). Today the city's urban green space sits at 602 hectares, about 1.97% of its land area, well below the 25% for a healthy urban ecosystem that is recommended by UNEP, along with not meeting the standard of 20 to 25 square meters of green space per resident recommended by WHO (Khan et al., 2023; Anjum et al., 2024). This deficit also causes Dhaka severe thermal stress, with peak Wet Bulb Globe Temperatures in central areas such as Ramna regularly exceeding the 32.2°C threshold, beyond which it becomes dangerous for outdoor workers. (Kamruzzaman et al., 2026). Dhaka's vehicular emissions alone release 100 kg of lead, 3.5 tons of suspended particulate matter, 1.5 tons of sulfur dioxide, 14 tons of hydrocarbons, and 60 tons of carbon monoxide daily (Pasha et al., 2021). In parallel, unplanned urban expansion has steadily encroached on the habitats that facilitate the region's biodiversity (Pasha et al., 2021). Dhaka's drainage infrastructure is overwhelmed every monsoon season, with chronic urban waterlogging plaguing the city (Pasha et al., 2021). Green infrastructure with permeable soil and water-retention capacity, such as Ramna Park's lake and grounds, is generally understood to relieve some of this pressure. However, this has not been independently measured or quantified anywhere in the available literature, and should be read as a plausible but unevidenced claim rather than a demonstrated impact in this assessment.Table 1: Ramna Park Visitor Profile | (Jahan et al., 2024)

21It also serves as a safe place for some of Dhaka's most vulnerable residents, with an Open School for Street Children running there. Visually impaired people use it to support themselves daily by begging, and it is known as an important place for including transgender individuals in society (Jahan et al., 2024; Sinthia, 2023). Ramna Park is protected by national and city policies such as the Dhaka Structure Plan (1995 and its 2016–2035 draft) which states that ramna park is a metropolitan Urban Park where open space must be kept safe. The Detailed Area Plan also limits business development inside the park, and the Waterbody Conservation Act (2000) protects its central lake from being taken over (IUCN Bangladesh & GCA, 2025). The Bangladesh Climate Change Strategy and Action Plan, (BCCSAP) 2009 and the National Adaptation Plan (2023–2050) also says that Ramna Park is a important city forest space to help reduce heat (IUCN Bangladesh & GCA, 2025). Researchers have studied the park’s plants and ecosystem services in detail (Pasha et al., 2021), written architectural and ecological theses (Kabir, 2009), looked into how easy it is to access (Sinthia, 2023; Niger, 2023), and tested the water quality of its central lake (Razzak et al., 2013), showing its value for study.Description of NbS Ramna Park functions as an urban green open space and arbor garden, often characterized as something similar to a human lung for the city (Pasha et al., 2021). It is organized around a widened network of brick and bituminous pedestrian paths, entered through seven designated gates that exclude motorized traffic, and centered on the 8.76-acre lake, with latest renovations adding a wooden-and- steel pedestrian bridge (Pasha et al., 2021). The park's ecological stability rests on two specific subsystems working in tandem with its infrastructure: a dense, multi-layered terrestrial forest canopy, and a freshwater lentic wetland formed by the central lake (Pasha et al., 2021). A 2020–2022 renovation, making use of a pandemic-related closure and funded through a 460-million-Taka PWD allocation, re-excavated the lake and added the lakeside wooden deck, repaved walkways, and upgraded recreational facilities (Pasha et al., 2021). The number of people who go through the park is controlled by a network of paths made of brick and bitumen, and this network can be accessed only through seven controlled gates in order to prevent vehicles from getting in; this design was intended both to protect the vegetation and at the same time to make sure the park remained fully walkable from end to end (Pasha et al., 2021). The 8.76-acre central lake, together with an adjacent water tank, anchors the park's spatial layout and provides its primary ecological and scenic function; the recent wooden-and-steel pedestrian bridge over the lake was added specifically to extend cooling, low-impact viewpoints across the water (Pasha et al., 2021). Infrastructure incorporates over 300 lakeside benches, shaded picnic huts, an outdoor low-impact fitness corner, a children’s playground and a cafe, all of which helps the park function as both a social and recreational hub, alongside its ecological functions (Pasha et al., 2021).The park was originally a landscaping initiative with an emphasis on aesthetics and recreation during the colonial and early post- colonial periods of redevelopment; today, at least in official and legislative documents, it is regarded as a means of promoting urban cooling, biodiversity conservation, and climate adaptation, rather than merely being for ornamental purposes (IUCN Bangladesh & GCA, 2025). The main beneficiaries of the park are the residents, students, and workers who live or study within a one-kilometre radius of the park, as well as more vulnerable groups, namely; street children, visually impaired people, and transgender residents, since the park provides them with a rare accessible public space (Jahan et al., 2024; Sinthia, 2023).

22A 25-sample quadrat survey across five vegetative zones cataloged 151 distinct plant species: 100 trees, 24 shrubs, 15 herbs, and 12 climbers, spanning ornamental and flowering species (58), timber species such as teak and mahogany (33), fruit-bearing species like jackfruit and mango (32), and medicinal species such as neem (28) (Pasha et al., 2021). In addition, the park is visited by 42 recorded bird species, with high winter visitations from mynas, bulbuls, kingfishers, and parakeets. Finally, 8 fish species in the lake and populations of butterflies, squirrels, and monkeys also form their habitats here (Pasha et al., 2021; Nahar et al., 2017). As a big picture, the park directly targets the problems identified in Section 2: dense, mature canopy cover drives a measurable cooling effect; the natural biomass filters ambient air pollution; its permeable ground and waterbody provide at least a qualitative stormwater buffer; and its species diversity sustains one of central Dhaka's last wildlife habitats.Evidence and ImpactsFigure 3: Satellite-derived thermal patterns of the park and surrounding neighborhood. (Source: Latitudo40)Thermal data, obtained from sample points within the park using satellite sensors, reveal a direct change associated with the maturing of the park's tree canopy, consisting of a decrease in average local temperatures of 0.16°C over the ten-year period from 2009 to 2019 (Pasha et al., 2021). According to a botanical quadrat analysis, the Simpson Diversity Index for the park's 151 recorded species is 0.73, on a scale in which 1.0 indicates the highest level of species richness; this shows that the plant community is both genuinely diverse and resilient (Pasha et al., 2021). The shading effect of the canopy lowers near-surface air temperature by between 1 and 5°C as a result of shade and evapotranspiration, a cooling effect that is estimated to extend 150 to 200 meters beyond the park's physical boundaries into the adjacent neighborhoods (Pasha et al., 2021). The Park acts as a carbon store due to its woody biomass, although the exact magnitude of this effect has not been precisely quantified (Pasha et al., 2021).

23A visitor survey using a five-point Likert scale assessed the different effects of the park in the following way: health and well-being (4.46, valued by 24% of users) came highest, then aesthetic value (4.34, 13%), followed by active recreation (4.28, 18%), social connection (3.93, 22%), relaxation (3.29, 15%), and biodiversity observation (3.25, 9%) which was rated the lowest; this indicates that most visitors appreciate the park mainly for exercise and mental restoration rather than for its ecological role (Jahan et al., 2024). The use related to health was concentrated along the outer jogging route, interest in aesthetic and biodiversity aspects was found around the lake and the inner paths, and social and relaxation use was distributed over the open lawns, as shown by the spatial mapping (Jahan et al., 2024). Moreover, access to the park has been associated with significantly higher self-esteem and social acceptance among older users, and also with more favorable public perceptions of tranquility in comparison with Dhaka's urban environment (Rahman & Shorkar, 2021; Sultana, 2022). The Park provides real provisioning value in those 32 kinds of edible-fruit and 28 types of medicinal plant are available to visitors, underprivileged residents regularly gathering biomass for various purposes, and the lake produces eight species of fish which are harvested under municipal control (Pasha et al., 2021). Moreover, it supports a noticeable informal economy since a restaurant, vendors of clothing and food, flower sellers, and tea stalls have all established themselves around the park, and it is believed to increase the values of nearby properties and rents, even though the real-estate premium has not been exactly quantified in the existing research (Pasha et al., 2021). The most clear and defensible contribution of the park with regard to climate resilience is one relating to temperature: by providing measured cooling both in the area of the park and in the surrounding buffer zone of 150 to 200 meters, it directly counteracts the urban heat island effect in Dhaka.IUCN NbS Self-Assessment This assessment was completed using the official IUCN Self-Assessment Tool for Global Standard of Nature-based Solutions (IUCN, n.d), scoring against evidence compiled from the sources previously cited in Sections 2 through 4 above. Ramna Park's completed self-assessment produced a total score of 69 out of 147 possible points (47%), placing it in the tool's "Partial" adherence band overall and indicating that the intervention does not fully adhere to the IUCN Global Standard for NbS in its current form. Scores varied considerably across the eight criteria, ranging from full absence of evidence on one criterion to adequate performance on four others, a pattern discussed criterion by criterion below.

24CRITERION 1: SOCIETAL CHALLENGES Criterion 1 scored 14 out of 18 which is 78 percent. This is considered adequate. Ramna Park directly and clearly responds to the challenges outlined in Section 2. It shows an impact by reducing urban heat with a cooling trend of 0.16°C over a decade. The park also provides the rated cultural ecosystem service according to visitor surveys health and well- being with a score of 4.46 out of 5. Additionally, it helps ease the lack of space in the heart of Dhaka, where such areas are very limited (Pasha et al., 2021; Jahan et al., 2024). CRITERION 2: INTEGRATED SYSTEMS PERSPECTIVE Criterion 2 received 7 out of 18, which equals 39% and is marked as insufficient. Ramna Park does not have a design or management plan that fits into an urban system. The governance of Ramna Park is divided in a way: the PWD runs the main park and nursery while the Dhaka City Corporation runs the nearby Shishu Park and car park. This split creates an arrangement instead of a coordinated one (Pasha et al., 2021). On top of that, new high‑rise buildings nearby are allowed to interfere with Ramna Park’s drainage and groundwater level. This shows that Ramna Park is not being planned with the rest of the city’s systems (Pasha et al., 2021). CRITERION 3: ENHANCED BIODIVERSITY, ECOSYSTEM INTEGRITY Criterion 3 scored 11 out of 21 (52%, Partial). The Park has real species diversity (a Simpson Index of 0.73) and a wildlife community that includes 42 bird species and 8 fish species (Pasha et al. 2021). However, the score is not very high because there is evidence that non-native and invasive tree species have been planted multiple times over many years without proper ecological checks. These non-native and invasive tree species have become more common than the native tree species. This means the park has biodiversity but does not show an improvement in the environment (Pasha et al., 2021). CRITERION 4: FINANCIAL FEASIBILITY & ECONOMIC JUSTIFICATION Criterion 4 received a score of 9 out of 15 (60%, Adequate). The park receives stable, long-term public funding through the Public Works Department (PWD), as demonstrated by the approximately 460- million-Taka renovation completed in 2022 (Pasha et al., 2021). However, the criterion did not achieve a higher score because no formal cost-benefit valuation is available in the literature, and secondary economic benefits, such as the real-estate premium discussed qualitatively in Section 4.3, remain unquantified rather than empirically demonstrated. CRITERION 5: INCLUSIVE GOVERNANCE & EQUITY Criterion 5 was given a score of 0 out of 27 (0%, Insufficient), which was the assessment's main conclusion. The governance of Ramna Park is completely top-down and is carried out by officials from the Central Public Works Department and the Arboriculture Department, with no formal procedures for consulting the community, involving them in co-design, or receiving public feedback (Pasha et al., 2021). The absence of participatory governance is also shown by documented cases of equity failures: 74% of the users are male whereas 26% are female, and women have raised specific safety concerns (Pasha et al., 2021; Rahman & Shorkar, 2021). Moreover, an accessibility study found the park to be hazardous for visitors who are visually impaired, since 70% of the people surveyed said that navigating the park was either difficult or dangerous because of undetectable gate barriers, unmarked steps, and the lack of tactile paving or Braille signage (Sinthia, 2023).

25CRITERION 7: ADAPTIVE MANAGEMENT Criterion 7 received a score of 10 out of 18 (56%, Partial). Evidence of adaptive management is observed in specific physical interventions, such as the introduction of concrete bank stabilization following Lake Shoreline erosion and the widening of walkways and installation of decks based on usage patterns during the 2020–2022 closure (Pasha et al., 2021). However, there is no systematic or continuous ecological or hydrological monitoring framework to scientifically guide these decisions. As a result, adaptation appears to be reactive to visible issues rather than informed by ongoing data collection (Pasha et al., 2021). CRITERION 8: ENHANCING SUSTAINABILITY & MAINSTREAMING Criterion 8 was given a score of 10 out of 15 (67 per cent, Adequate). Ramna Park enjoys permanent legal protection since it has been designated a National Park, is fully incorporated into the Dhaka Structure Plan, and is given consistent annual funding for operations from the national budget (Pasha et al., 2021; IUCN Bangladesh & GCA, 2025). These elements thus form a solid institutional basis for long- term sustainability. The rating has not been assigned as "Strong" because the threats which have not yet been resolved such as those involving invasive species and fragmented governance identified in Criteria 2 and 3 still pose a challenge to long-term sustainability. Overall Assessment Summary The eight scores as a whole show a clear and consistent pattern: Ramna Park shows adequate to strong performance when it comes to the criteria that assess direct environmental and societal outcomes (Criteria 1, 4, and 8) and only partly meets the criteria relating to ecological and adaptive processes (Criteria 3, 6, and 7). It, however, does badly on the two criteria which assess systemic integration and inclusive governance (Criteria 2 and 5). Since, according to the IUCN's framework, a Nature-based Solution (NbS) is only as robust as the process that underpins it, Ramna Park is at present functioning more like an ecological asset that has been inherited than as a deliberately managed Nature-based Solution. Strengths, Limitations and Challenges Ramna Park shows good thermal performance, since satellite data has shown a cooling effect of 0.16°C over a ten-year period that reaches 150 to 200 metres beyond the park's edges into the neighbouring areas (Pasha et al., 2021). The park also functions as Dhaka's main socio-cultural centre by hosting the national Pahela Baishakh festival and promoting social inclusion among elderly people, street children, and transgender individuals (Pasha et al., 2021; Rahman & Shorkar, 2021). According to surveys of visitors, health and well-being services were the most highly rated feature, receiving a score of 4.46 out of 5 (Jahan et al., 2024). Several documented failures have been found. Research comparing the vegetation shows that 35.8% of the individual trees and 35.5% of the species in Ramna Park have suffered direct physical damage, such as bark incisions, carved graffiti, and stem breakage. By contrast, almost no similar damage is seen in the access-restricted National Botanical Garden (Kashem et al., 2025). The central lake is highly polluted because of discharges from municipal drains, visitors leaving litter, and the use of detergents for washing and bathing. This leads to increased levels of biochemical oxygen demand and turbidity, thereby endangering aquatic life (Razzak et al., 2013). Moreover, the park's area has shrunk from 88.5 to 68.5 acres over the last century as a result of commercial and administrative buildings spreading into the land (Pasha et al., 2021).

26The unintended risks involve the spread of invasive and non-native tree species, these now exceeding the native ones and as a result damaging the local ecological food chain (Pasha et al., 2021). Moreover, since fast-growing but structurally weak softwood trees are dominant, the likelihood of falling trees during storms rises (Pasha et al., 2021). The fact that there is standing water in the lakes together with dense vegetation also promotes mosquito breeding, a problem that has been recorded in Dhaka's parks (Bashar et al., 2014). Also, the requirement for the park to close mandatoryly in the afternoons and at night, even though the police and the Ansar patrols are still operating, limits the access which the park is meant to offer (Pasha et al., 2021). The main disadvantage of the park is the presence of equity gaps, and a study into accessibility has discovered that the environment presents a real danger to people who have visual impairments. Because of unnoticeable low-height gate barriers, steps without markings, and the lack of tactile paving, contrast markings, or Braille signage, 70% of the visually impaired visitors who were surveyed said that navigating the park was either difficult or dangerous (Sinthia, 2023). Moreover, access to the park is strongly influenced by gender, with 74% of users being male and 26% female. Women have raised particular safety concerns and have been affected by cultural restrictions which have limited their use of the area (Pasha et al., 2021; Rahman & Shorkar, 2021). Even though the park is in a central location, the cost and difficulty of public transport in Dhaka place a heavy burden on low-income families who live further away, so that consistent use is effectively limited to those who live nearby and are more affluent (Pasha et al., 2021). The main issue in the park is finding a balance between open public access and the need for ecological protection. Allowing unrestricted entry means that the park can serve as Dhaka's most commonly used and socially inclusive green area. At the same time, this open access also leads directly to vandalism, damage to the trees, and pollution of the lake, as has already been recorded. Instead of addressing this dilemma, Ramna Park has taken on the costs connected with it, a situation that is shown by its "Partial" rating on IUCN Criterion 6. The overall IUCN self-assessment score for Ramna Park of 47% puts it below the level needed to be in full compliance with the Global Standard; yet this score might underestimate the park's strengths and overstate its weaknesses. It shows adequate to strong performance in regard to environmental and social criteria that can be directly measured, such as heat mitigation, health and recreation benefits, financial stability, and long-term legal protection. The main reasons for the low total score are institutional: there is a total lack of inclusive governance (scoring 0% on Criterion 5) and weak integration with the wider urban system (39% on Criterion 2), both of which are related to processes and not to ecological problems. Although Ramna Park acts as an effective example of green infrastructure, it has not been managed as a deliberately designed Nature-Based Solution. Its physical characteristics namely the dense mixed-species canopy, the central water body, permeable ground, and controlled pedestrian access are valuable examples that can be copied in other parts of Dhaka. There is a risk, however, of repeating the same shortcomings in regard to governance at new sites if the physical design alone is copied without also introducing participatory governance, ecological monitoring, and measures to ensure universal accessibility. In order to scale this model responsibly, governance reform must be given priority as a necessary step before any expansion takes place.

27References Anjum, B., Sultana, R., & Saddaf, N. (2024). The effectiveness of nature-based solutions to address climate change in Dhaka, Bangladesh. Social Sciences & Humanities Open, 10(100985), 1–16. https://doi.org/10.1016/j.ssaho.2024.100985 Bashar, K., Rain, F. F., Jesmin, M., & Asaduzzaman. (2014). Surveillance of mosquitoes in some selected parks and gardens of Dhaka city, Bangladesh. International Journal of Mosquito Research, 1(2), 5–9. IUCN. (n.d.). IUCN Global Standard for Nature-based Solutions Self-Assessment Tool. International Union for Conservation of Nature. https://inbs.iucn.org/apply/nature-based-solutions-self-assessment/tool/ IUCN Bangladesh & Global Center on Adaptation. (2025). Compendium on nature-based solutions for urban resilience in Bangladesh (pp. xviii + 222). International Union for Conservation of Nature (IUCN) and Global Center on Adaptation (GCA). Jahan, N. N., Mozomdar, A. R., Saika, U., Hossain, M. I., & Ansari, M. N. A. (2024). Understanding of cultural ecosystem services in urban green spaces: A case study in Ramna Park, Dhaka, Bangladesh. Open Access Library Journal, 11(e11113), 1–18. https://doi.org/10.4236/oalib.1111113 Kamruzzaman, M., Kamal, A. S. M. M., Talukder, A., Jain, F. C., Khan, A. K. M. R. A., Rahman, M. M., Asaduzzaman, M., & Shahid, S. (2026). High-resolution WBGT-based assessment of urban heat stress in Dhaka, Bangladesh (2008–2017): Implications for climate-responsive planning. City and Environment Interactions, 30, 100329. https://doi.org/10.1016/j.cacint.2026.100329 Kashem, M. A., Rahman, M. A., Hussaini, S. M., & Hossain, M. Z. (2025). Human-plant interactions in the urban vegetation: A comparative study between the National Botanical Garden and Ramna Park, Dhaka. Research Article (DU), 22(9), 191–200. Khan, M. W., Hossain, M. S., & Alam, M. (2023). GIS-based analysis to identify the distribution and accessibility of urban green space in Dhaka metropolitan city, Bangladesh. Journal of Geographic Information System, 15, 35–52. https://doi.org/10.4236/jgis.2023.151003 Nahar, S., Akter, M. T., Khan, S. S., Jahan, S., Mostofa, M. S., & Das, D. K. (2017). Winter assemblage of birds and mammals on the fruited canopy of Ficus bengalensis and Ficus religiosa at Ramna Park, Dhaka, Bangladesh. Jagannath University Journal of Life and Earth Sciences, 3(1&2), 14–20. Niger, M. (2023). Analyzing accessibility of public open space in relation to urban configuration of Dhaka city. Journal of Research in Infrastructure Designing, 6(2), 1–15. Pasha, A. B. M. K., Chowdhury, A. H., Hussain, A., Rahman, M., Mozumder, S., & Dela Fuente, J. A. (2021). Identification of the ecosystem services and plant diversity in Ramna Park Dhaka. Science Progress and Research, 1(4), 345–356. https://doi.org/10.52152/spr/2021.141 Rahman, K. M. A., & Shorkar, M. A. N. (2021). Analyzing association between public green space and self- esteem linked to social acceptance for elderly people in Dhaka city. SAGE Open, 11(4), 1–16. https://doi.org/10.1177/21582440211054473 Razzak, N. R. B., Siddik, A. Z., & Ahmeduzzaman, M. (2013). Evaluation of water quality of Ramna and Gulshan lakes. International Journal of Environmental Monitoring and Analysis, 1(6), 273–278. https://doi.org/10.11648/j.ijema.20130106.11 Sultana, S. (2022). Measuring public perception about tranquility of urban park: A survey on park use in Dhaka city. In Proceedings of IASTEM International Conference (pp. 16–23). IASTEM.

4 Evaluating the Potential of Gulshan Lake as a Nature-Based Solution for Urban Environmental Resilience Mohsina Radia Maqfi, Youshra Zabeen Sarah, & Shaima Akter SharahAbstract Rapid urbanization in Dhaka has replaced wetlands and permeable surfaces with impervious infrastructure, intensifying surface runoff and straining the city's drainage systems, particularly during the monsoon season. Gulshan Lake, a major urban water body extending across Gulshan, Banani, and Baridhara, forms part of the broader Hatirjheel-Gulshan-Banani lake system and plays a significant hydrological role in stormwater retention and regulation. Covering approximately 58.86 hectares with a mean depth of about 2.5 metres, the lake possesses substantial physical capacity to store urban runoff and interacts with surrounding drainage channels as part of the city's wider water-management network. In this paper, we discussed about Gulshan Lake’s background along with its context also how Gulshan Lake works as a hybrid Nature-Based solution. Gulshan Lake is hydrologically linked to the Hatirjheel-Begunbari-Balu-Shitalakhya system, contributing to stormwater retention, groundwater recharge, and biodiversity habitat. Combining it with low-impact development measures like permeable paving and bioretention could reduce peak stormwater discharge, supporting a hybrid grey-green drainage strategy. However, Microplastic contamination in its water, sediment, and fish further reflects this pollution pressure. This is the central NBS paradox: the same urban density that benefits from the lake’s drainage functions also drives its pollution, so restoration must prioritize source control through sewage diversion, waste management, and coordinated governance, over lake cleaning alone. Keywords: Gulshan Lake; Nature-Based Solutions; Stormwater Management; Urbanization; Microplastic ContaminationDepartment of Disaster Management and Environmental Studies, Brac University, BangladeshIntroduction Dhaka’s rapid urbanization has significantly altered its natural landscape, with increasing constructions of buildings, roads, and other infrastructure replacing wetlands and permeable land (Haque,2026). The expansion of impervious surfaces such as concrete and asphalt reduces the ground’s ability to absorb rainfall, resulting in greater surface runoff. This problem becomes particularly severe during monsoon, when heavy rainfall places considerable pressure on the city’s already strained drainage systems. (Haque ,2026). Inadequate drainage capacity, blocked channels, and the loss of natural water retention areas often prevent rainwater from being discharged efficiently. Consequently, urban flooding and water logging have become recurring challenges in Dhaka, disrupting transportation, damaging infrastructure and affecting resident’s daily lives. These conditions highlight the importance of preserving and effectively managing urban water bodies that can help store and regulate excess rainwater (Haque,2026).28

29Gulshan Lake is a city scale urban water body extending across Gulshan, Banani, Baridhara in Dhaka, covering parts of several city wards (Ahmed & Mohuya,2013). The lake systems serve an important hydrological function as a stormwater retention area, helping store and regulate runoff (Ahmed & Mohuya,2013). It is also connected to Dhaka’s wider drainage network, with Gulshan and Banani lake discharging into Hatirjheel, linking the system to surrounding drainage channels and catchments. As one of Dhaka’s major urban lakes, Gulshan Lake therefore plays a broader city level role in stormwater management (Mercy, F.,T.,2023). Despite its potential stormwater and ecosystem functions, Gulshan Lake faces severe environmental degradation. Studies have reported substantial anthropogenic pollution, including high biochemical oxygen demand, nitrate and phosphate concentrations and critically low dissolved oxygen levels, indicating strong eutrophication potential ecological stress (Rahman,2021). Microplastic contamination further threatens the lake’s aquatic environment, with Gulshan Lake recording relatively high concentrations of microplastics in both water and sediment (Mercy,F,.T.,2023). These pollutants are associated with domestic wage, industrial discharge and stormwater runoff, creating growing concerns for aquatic life and the ecological health of the lake (Rahman,2021). This paper aims to assess the extent to which Gulshan Lake functions as a hybrid Nature-Based Solution for urban stormwater management and environmental resilience in Dhaka. It examines the lake’s hydrological and ecological functions, its environmental, social and climate related impacts, and its strength and limitations using IUCN Global Standard for Nature-Based Solutions Self- Assessment framework.Background and Context Dhaka has experienced rapid urbanization, resulting in extensive conversion of natural and permeable land into built up areas. The expansion of buildings and roads, and other impervious surfaces reduces the land’s capacity to absorb rainfall and increase surface runoff. Recent research on the Hatirjeel-Gulshan-Banani lake system shows that build up land accounted for 56.43% of the drainage area in 2024, contributing to substantial runoff generation (Haque,2026). During the monsoon, intense rainfall places additional pressure on Dhaka’s drainage infrastructure, increasing the risk of urban flooding and waterlogging. At the same time, the expansion of urban areas and constrained drainage systems place increasing pressure on natural water bodies, which are important for storing and regulating stormwater (Haque,2026). Gulshan Lake is a major urban water body situated within one of the most highly urbanized part of Dhaka, surrounded by dense residential, commercial and institutional development. It forms part of the broader Hatirjheel-Gulshan-Banani lake system and contributes to urban stormwater retention and drainage (Haque,2026). The lake covers approximately 58.86 hectares and has a mean depth of about 2.5 meters, giving it important physical capacity for storing urban runoff. Gulshan Lake is also recognized as one of Dhaka’s major urban lakes and has been studied for its environmental conditions and contaminations (Mercy,2023). Its location within a densely developed catchment makes its hydrological function particularly important, while its connection with surrounded drainage channels allows it to interact with the wider urban water-management system (Haque,2026). Gulshan Lake faces a complex environmental challenge because it must function as a stormwater retention area while receiving pollutants from its surrounding urban environment. During heavy rainfall, extensive impervious surfaces generate increased runoff, placing pressure on drainage systems and contributing to waterlogging and flooding (Haque,2026). Studies have identified municipal wastewater discharge as a major point source of pollution, while surface runoff becomes particularly important during wet season (Rahman,2021). These inputs increase nutrient loading, particularly nitrogen and phosphorus, contributing to eutrophication and declining water quality.

30These inputs increase nutrient loading, particularly nitrogen and phosphorus, contributing to eutrophication and declining water quality. It was reported that that extremely low dissolved oxygen and high concentrations of biochemical oxygen demand, phosphate and nitrate in Gulshan Lake, indicating severe anthropogenic pollution (Rahman,2021). Microplastic contamination adds another layer of ecological stress; Gulshan Lake recorded the highest microplastic concentrations among the three major urban lakes studied in Dhaka, reaching 36 items/L in water and 67 item/kg in sediment (Mercy,2023). Gulshan Lake exists at the intersection of two problems: the need to retain and manage urban stormwater and the need to project a highly degraded urban ecosystem. Description of the Nature-Based Solution Nature-based solutions (NbS) are solutions that use natural or altered ecosystems to respond to societal challenges and at the same time provide benefits for people and biodiversity. (International Union for Conservation of Nature [IUCN], 2025) The IUCN global standard is intended to offer guidance on designing, assessing and upgrading NbS. (IUCN, 2025) In the present paper, Gulshan Lake is regarded as a hybrid NbS as currently existing ecosystem services in concert with artificial drainage and water-management infrastructure are utilized. Gulshan Lake is one of the large urban lakes in the capital city of Dhaka, Bangladesh. The lake is surrounded by high-class residential and commercial places, which are highly developed with infrastructure (Mercy et al., 2023). The size of this lake is 58.86 ha, and its average depth is 2.5 meters (Mercy et al., 2023). This body of water is a significant feature in one of the most densely developed regions of Dhaka. Due to the lack of space for expansion, the water area is subject to the pressures of the surrounding urban infrastructure. The Gulshan-Banani-Baridhara Lake Development Project was implemented for the development and protection of the lake and associated ecosystem. Activities included lake excavation, embankment protection, road and pathway construction, causeway, tree planting, streetlighting and others. Its main goals were to protect the lake from encroachments, increase its water storage capacity, and improve the natural environment as well as offer recreational and walkable avenues. (Mohammed Mostafa & Mohammed Mostafa, 2026) These interventions show that the lake has been recognized as an important element of Dhaka’s urban environmental and recreational infrastructure. However, it should be noted that the project mainly focused on a lake-development/restoration intervention and was not initially conceived in the modern approach of Nature-based Solutions. Gulshan Lake can contribute to the local stormwater management in Dhaka by offering a place for the temporary storage of the water. The lake can serve the purpose of a system that helps to regulate the run-off of rainwater from the urban area into the city’s stormwater drains (IUCN, 2020). The increased impervious surface area as a result of the urbanization process raises the amount of run-off water substantially, and it can be beneficial to utilize the advantages of nature-based solutions to retain and store it (IUCN, 2020). Gulshan Lake is an urban freshwater ecosystem, which delivers essential ecological services despite being highly transformed by the urbanized environment around it. However, the lake’s ecological functioning has been compromised due to pollution and other human activities. (Rahman & Hossain, 2018; Mercy et al., 2023) Studies on microplastics in urban lakes of Dhaka have discovered that Gulshan Lake has the highest content of microplastics among the studied sites. Specifically, Mercy et al. (2023) have found that surface water in Gulshan Lake contained 36 microplastic items/L while bottom sediment had 67 microplastic items/kg, which is comparably high to the other lakes studied. (Mercy et al., 2023) As such, the lake appears to provide some degree of ecological services, yet its capacity to deliver healthy and high-quality ecosystemic services is limited due to the lake being subjected to severe environmental degradation. Gulshan Lake is a good example of a recreational and social utility in the context of urban infrastructure in Dhaka (Iqbal et al., 2009). As such, it can be considered as an important resource that can serve multiple purposes, ranging from recreation to conserving environmental and social values in the area.

31Evidence and Impacts Gulshan Lake is an asset to the urban environment due to its ability to sustain an open-water ecosystem in a densely built-up region of Dhaka. Urban lakes are beneficial and can provide habitat for ecological services if their biogeochemical cycles are respected. However, the evidence claims that the lake’s sustainability capabilities are compromised by anthropogenic activity and pollution. Rahman and Hossain (2019) highlight increased pollution levels, decrease in dissolved oxygen, eutrophication episodes, and heavy metal pollution in Gulshan Lake as major environmental concerns. The proper functioning of Gulshan Lake as an integrated urban water system relies on the quality of the water. It has been stated that the lake has a low level of dissolved oxygen and a high biochemical oxygen demand, together with a high content of nutrients and other pollutants (Rahman et al., 2021). The authors point out that this pollution is caused by municipal wastewater and surface runoff entering the water body. The research illustrates the way in which pollution can affect the functioning of ecosystems and shows that it is important to keep water bodies clean if one is to obtain the greatest benefits; for this reason, water quality is of primary importance in the study. The study only indicates how polluted the lake is, rather than showing how much pollution the lake removes. The recreation and open space value of Gulshan Lake could also have social benefits because blue-green infrastructure (BGI) can contribute to enhancing people’s wellbeing and to making cities better places to live in. However, this evidence is not conclusive. For example, Venkataramanan et al. (2019) found that green infrastructure for stormwater and flood management can provide social and health benefits, but they also identified several limitations in the evidence. As a result, even though Gulshan Lake’s recreational and open space value could contribute to urban livability, it cannot be concluded that it will necessarily yield significant health benefits. Maintaining Gulshan Lake as a component of the urban green-blue infrastructure may well be of economic value by contributing to a more resilient urban environment and reducing the need for grey infrastructure, as suggested by Ruangpan et al. (2020). The NbS has the potential to offer cost-effective and multi-functional approaches to hydro-meteorological risk reduction. In terms of Gulshan Lake, it suggests that the preservation of the existing natural infrastructure may well have economic benefits in addition to the environmental benefits, though they must be weighed against the costs of lake maintenance, pollution control, and restoration. Overall, the main strength of Gulshan Lake as a hybrid NbS lies in the unique combination of environmental, stormwater, and social functions it can provide within a single urban area. Indeed, Ferrario et al. (2024) concluded in their study that NbS can effectively reduce the city’s exposure to flood-related hazards through a meta-analysis. This allows considering Gulshan Lake as a hybrid system where natural water-storage processes are combined with specific engineered solutions related to drainage and management. On the other hand, the limitation of the source is that it does not specifically analyze Gulshan Lake, meaning that the results may not fully apply to the case in question. The provided information indicates that Gulshan Lake may offer significant environmental and social benefits. However, based on the presented performance indicator, it is not possible to conclude that Gulshan Lake is an effective NbS solution. The IUCN Global Standard highlights the importance of considering various aspects of NbS. In this regard, it may be concluded that in order to assess the effectiveness of Gulshan Lake as an NbS solution, it is necessary to analyse the changes in water quality, water level, drainage function, biodiversity, recreation opportunities and encroachment. IUCN NbS Self-Assessment Evaluation of Gulshan Lake according to the eight Nature-based Solution criteria shows that the site has potential to be an urban NbS, though with significant weaknesses. Plots in this lake scored between 0% and 50%, which is a mediocre result. Being an urban area, Gulshan Lake is a key wetland in Dhaka. However, this water body has been subject to many human-induced influences such as sewage, runoff, and urbanization, among others.

32Figure 1: Our NBS self-assessment ResultsSocietal Challenges Addressing societal issues has been scored the highest at 50%. This is a suitable score for Gulshan Lake as it is directly involved with many of the issues affecting the local community. Water pollution, foul odors, breeding grounds for mosquitoes, poor environmental quality, drainage and flooding problems, and the loss of a healthy recreational site are some of the problems. Many people are directly affected by the lake’s poor state due to its proximity to residential and commercial properties. Therefore, addressing the lake’s problems would bring about many societal benefits such as improved living conditions, a cleaner environment, and more recreational sites. Gulshan Lake’s cleanliness and status as an urban nature area have been of great interest to the government. The fact that the plot only scored 50% suggests that the problems affecting society through this lake have not been adequately addressed. Integrated Systems Perspective According to the integrated systems perspective, Gulshan Lake is also a significant challenge as it scored 44%. This factor is crucial in determining the success of any project, as the lake cannot be considered an isolated entity. The water body’s condition is directly determined by the surrounding system that includes drains, roads, buildings, sewerage, rainfall patterns, urban sprawl, and the local community. For instance, the lake’s pollution is not only caused by water but also by the nearby impoundments. Therefore, improving the state of Gulshan Lake will require looking at other aspects beyond the lake, such as improving the sewerage system and addressing unauthorized discharge connections. The score of 44% shows that this factor has been considered partially and needs more attention. Enhanced Biodiversity and Ecosystem Integrity According to the enhanced biodiversity and ecosystem integrity, Gulshan Lake scored poorly at 19%. Even though this water body is an essential urban ecosystem, it has been significantly compromised by the high pollution levels. Recent research has shown that Gulshan Lake has very low levels of dissolved oxygen and is highly polluted, thus unsuitable for most aquatic life. The water body also contains high concentrations of microplastics, according to some studies. Therefore, cleaning up the lake requires a more comprehensive approach than merely removing the trash. An NbS intervention would focus on restoring the lake’s ecological functions, such as improving the water quality, providing habitats and food for the local species, and enhancing the general conditions of the wetland. Thus, the low score suggests that currently, Gulshan Lake does not demonstrate signs of improved biodiversity and healthy ecosystems.

33Financial Viability and Economic Justification With regards to financial viability and economic justification, Gulshan Lake scored 13%. One of the most apparent flaws with the current plan is the lack of funding for maintaining and protecting this water body. The rehabilitation of this lake will require continuous investment in water treatment, sewerage, maintenance, and monitoring if long-term positive change is to be achieved. Therefore, the project should demonstrate its financial sustainability and the source of funding for maintenance and management costs. In turn, investing in this project will yield several economic benefits, including increased property value and tourism revenue. Additionally, the NbS intervention will provide ecological and social value, which makes it a viable investment option. Inclusive Governance and Equity Concerning inclusive governance and equity, Gulshan Lake also scored poorly at 19%. This site is a complex system that hosts various stakeholders, including agencies, residents, businesses, communities, environmental groups, and recreational users. One of the central concerns regarding Gulshan Lake is that the project will not address the needs of all community members adequately. For instance, if the restoration process requires removing any part of the lake, it could cause adverse effects to the people who use it as a resource. Balancing Goals and Impacts According to the balancing goals and impacts criterion, Gulshan Lake scored 0%, which is a failing mark. The analysis did not reveal any information suggesting that the restoration process will take into account the different interests of the stakeholders. This is a crucial factor to consider when developing NbS interventions because beautification and recreational opportunities could conflict with ecological integrity and community development. For instance, constructing new recreational facilities around the lake might involve developing wetland areas, which will negatively affect biodiversity. Similarly, if the restoration process requires removing informal housing, it might cause adverse impacts to the residents. Therefore, the rehabilitation of Gulshan Lake must consider balancing the various benefits and possible adverse effects that may arise during the implementation phase. Adaptive Management According to the adaptive management criterion, Gulshan Lake scored 17%. This low mark suggests that there is insufficient information on the management and monitoring of this project after its implementation. It is necessary to keep track of the water quality and the general state of the lake’s ecosystems after the intervention has been completed. This way, it will be possible to determine what NbS measures are most effective and make adjustments where necessary. Enhancing Sustainability and Mainstreaming Enhancing sustainability and mainstreaming scored 33% for Gulshan Lake. This criterion illustrates the potential of this water body to become a central part of the urban area’s ecological functions. At present, the government is working on rehabilitating Gulshan Lake to improve its sewerage system and prevent illegal waste disposal. According to the government, unauthorized sewage connections have been a significant source of pollution for Gulshan and Baridhara lakes, which have severely contributed to water quality problems and environmental damage. Therefore, in July 2026, authorities directed RAJUK to seal illegal sewer pipes in Gulshan and Baridhara and undertake steps to restore the wetlands and enhance the environmental quality of the area. Overall, Gulshan Lake has the potential to be a successful Nature-based Solution, though with several weaknesses. The findings show that the strongest aspect of this project is its ability to address many urban and social challenges, whereas adaptive management and balancing goals and impacts are the weakest factors. The 0% score in the balancing goals and impacts criterion is surprising considering the importance of this criterion in NbS.

34Gulshan Lake: Strengths, Limitations, And Challenges Existing natural/modified water body: Gulshan Lake is a major urban water body in Dhaka and forms part of a connected water system extending through Hatirjheel, Begunbari Khal, the Balu River and the Shitalakhya River. Its position in this chain means that its hydrology and water quality can affect downstream drainage and ecosystems (Ahmed, 2017). Stormwater retention: The lake contributes to the wider urban drainage network by receiving and retaining stormwater before conveying water through connected channels. Its connection with Hatirjheel is particularly important because the broader lake–canal system was developed partly to retain and drain stormwater in Dhaka (Khan, n.d.; World Bank, 2019). Connected to the wider urban water system: Gulshan Lake is hydrologically linked with the Hatirjheel–Begunbari detention basin and connected canals. This network allows the lake to contribute to urban water conveyance, but it also means that upstream pollution can move through the system and affect downstream water bodies (Ahmed, 2017; Khan, n.d.). Provides environmental services: Despite degradation, the lake still contributes to groundwater recharge, microclimate regulation, and biodiversity habitat in an otherwise highly built-up area (Faria, Ariyan and Mia, 2024). Potential contribution to climate resilience: Gulshan Lake can contribute to climate adaptation when combined with low-impact development (LID) measures, including permeable paving, bioretention, vegetated drainage, and rainwater harvesting. Such interventions reduce runoff at source and reduce pressure on the lake and conventional drainage systems (Ahmed et al., 2026). Can complement grey infrastructure: Modelling for the Hatirjheel- Gulshan- Banani system shows that LID measures (e.g., permeable surfaces, bioretention) could reduce peak discharge by roughly 8–13% for design storms, indicating that the lake works best as part of a hybrid grey-green system (Ahmed et al., 2026). Severe water pollution: Gulshan Lake receives domestic sewage, commercial wastewater, solid waste and contaminated urban runoff. Water-quality monitoring identified very low DO and high BOD, indicating substantial organic pollution (Ahmed, 2017). Rahman (2019) also identified ammonia enrichment, oxygen depletion and toxic metals including lead, chromium and cadmium as major concerns. Microplastic contamination: Microplastic pollution is another major limitation. Mercy, Alam and Akbor (2023) detected microplastics in water, sediment and fish from Dhaka’s major urban lakes. Gulshan Lake had relatively higher concentrations in water and sediment; the study reported a maximum of 36 microplastic items per litre in water and 67 items per kilogram in sediment. Poor ecosystem health: Sediments show high oxygen demand and contamination (including heavy metals like Cd and Pb), which sustains low dissolved oxygen and degrades habitat quality (Rahman, 2019; Faria, Ariyan and Mia, 2024). Limited quantified co-benefits: While drainage and amenity values are clear, there is limited quantified evidence on co-benefits (for example, property value effects, health outcomes, recreation economics) specific to Gulshan Lake.Conclusion Gulshan Lake illustrates both the value and the vulnerability of nature-based solutions in a rapidly urbanising city. As an existing urban water body connected to the Hatirjheel–Gulshan–Banani drainage network, it can contribute to stormwater retention, runoff regulation, habitat provision, local cooling and urban amenity.

35Its role becomes particularly important during monsoon rainfall, when open-water storage and connected drainage channels can help reduce pressure on Dhaka’s conventional drainage infrastructure. Modelling suggests that combining the lake system with low-impact development measures could reduce peak stormwater discharge by approximately 7.9–12.7%, demonstrating the potential of a hybrid grey–green approach (Ahmed et al., 2026). However, Gulshan Lake cannot presently be regarded as a fully effective NBS because its ecological condition is severely compromised. Untreated wastewater, organic pollution, nutrient loading, heavy metals, plastic waste and contaminated runoff have contributed to hypereutrophic conditions, low dissolved oxygen and declining habitat quality (Rahman, 2019; Faria, Ariyan and Mia, 2024). Microplastic contamination in its water, sediment and fish further illustrates the intensity of human pressure on the lake ecosystem (Mercy, Alam and Akbor, 2023). This represents the central NBS paradox. The same dense urban environment that benefits from Gulshan Lake’s drainage and amenity functions also produces the sewage, runoff and waste that undermine its ecological capacity. Therefore, restoration must focus on preventing pollution at source, rather than relying only on lake cleaning or landscape beautification. Gulshan Lake’s approach could be adapted to other Dhaka lakes and canals, but successful replication depends on integrating hydrology, ecosystem protection, land- use control, maintenance and institutional accountability. References Ahmed, M. (2013). Water quality and pollution sources of Gulshan Lake. International Journal of Information Technology and Business Management, 16(1), 78–82. Ahmed, S. U., & Mohuya, F. A. (2013). Growth and development of Dhaka North: 1971–2011. Journal of the Asiatic Society of Bangladesh (Humanities), 58(2), 303–334. Faria, F. F., Ariyan, T. N., & Mia, M. Y. (2024). Trophic status analysis and nutrient source allocation in urban lakes of Dhaka, Bangladesh: A comprehensive approach to eutrophication monitoring. Environmental Monitoring and Assessment, 196, 1252. https://doi.org/10.1007/s10661-024-13419-y Ferrario, F., Mourato, J. M., Rodrigues, M. S., & Dias, L. F. (2024). Evaluating nature-based solutions as urban resilience and climate adaptation tools: A meta-analysis of their benefits on heatwaves and floods. Science of the Total Environment, 950, 175179. https://doi.org/10.1016/j.scitotenv.2024.175179 Haque, M. M., Islam, M. S., Ghosh, P. K., & Dey, T. (2026). Low-impact development and 17 sponge city adaptation for urban stormwater retention in Dhaka: Assessing the Hatirjheel–Gulshan–Banani lake system. Asian Journal of Water, Environment and Pollution. https://doi.org/10.36922/AJWEP026190136 Iqbal, M. M., Higuchi, T., Ueda, A., & Miyazaki, K. (2009). Dhaka city’s park users’ profile, recreational habits and their satisfaction. Dezaingaku Kenkyu/Dezaingaku Kenkyū, 56(1), 101–108. https://doi.org/10.11247/jssdj.56.101_1 IUCN. (2020). IUCN global standard for nature-based solutions: A user-friendly framework for the verification, design and scaling up of NbS (1st ed.). https://doi.org/10.2305/IUCN.CH.2020.08.en Khan, M. S. A. (n.d.). Hatirjheel–Begunbari detention basin and linked lake system [Teaching material]. Bangladesh University of Engineering and Technology.

36Mercy, F. T., Alam, A. K. M. R., & Akbor, M. A. (2023). Abundance and characteristics of microplastics in major urban lakes of Dhaka, Bangladesh. Heliyon, 9(4), e14587. https://doi.org/10.1016/j.heliyon.2023.e14587 Mohammed Mostafa. (2026, July 31). Beauty by the lake, garbage in the water. Prothom Alo. https://en.prothomalo.com/bangladesh/yk4gd81up5 Rahman, K., Barua, S., & Imran, H. (2021). Assessment of water quality and apportionment of pollution sources of an urban lake using multivariate statistical analysis. Cleaner Engineering and Technology, 5, 100309. https://doi.org/10.1016/j.clet.2021.100309 Rahman, S. S., & Hossain, M. M. (2019). Gulshan Lake, Dhaka City, Bangladesh, an onset of continuous pollution and its environmental impact: A literature review. Sustainable Water Resources Management, 5(2), 767–777. https://doi.org/10.1007/s40899-018-0254-4 Ruangpan, L., Vojinovic, Z., Di Sabatino, S., Leo, L. S., Capobianco, V., Oen, A. M. P., McClain, M. E., & Lopez- Gunn, E. (2020). Nature-based solutions for hydro-meteorological risk reduction: A state-of-the-art review of the research area. Natural Hazards and Earth System Sciences, 20(1), 243–270. https://doi.org/10.5194/nhess-20-243-2020 Venkataramanan, V., Packman, A. I., Peters, D. R., Lopez, D., McCuskey, D. J., McDonald, R. I., Miller, W. M., & Young, S. L. (2019). A systematic review of the human health and social well-being outcomes of green infrastructure for stormwater and flood management. Journal of Environmental Management, 246, 868– 880. https://doi.org/10.1016/j.jenvman.2019.05.028 World Bank. (2019). Flood risk management in Dhaka: A case for eco-engineering approaches and institutional reform. World Bank.

5 Case Study of Zinda Park as a viable Nature-based Solution (NbS) Syeda Noushin Jahan Prova, Zahra Rubby, & Omar HossainAbstract Zinda Park is a good example of how nature can be used to create a healthier and more sustainable environment for people. Located in Narayanganj, Bangladesh, the park combines trees, ponds, green spaces, plants and open areas to provide both environmental and social benefits. These natural features help reduce heat, improve air quality, support different types of plants and animals, and manage rainwater. At the same time, the park gives people a place to relax, spend time with family and friends and connect with nature. This study looks at Zinda Park as a Nature-Based Solution (NbS) and examines how the ongoing issues such as Urban encroachment, Water pollution, Lake siltation, Soil erosion, Over-tourism strain, Waste accumulation, Ecosystem disruption, Boundary dispute can be reformed & fixed. It focuses on the environmental, social, economic and climate-resilience benefits of the park, as well as the role of different stakeholders such as visitors, local communities, park management and government authorities. Based on the assessment, Zinda Park received a score of 69, which shows that it has a fairly strong application of NbS principles, although there is still room for improvement in areas such as monitoring, stakeholder involvement, and measuring long-term impacts. Keywords: Zinda Park; Nature-Based Solutions;Department of Disaster Management and Environmental Studies, Brac University, BangladeshIntroduction The advent of Zinda Park, the area of Rupganj Upozila, suffered significantly from the impacts of urbanization. This region faces climate threats like riverbank erosion and flooding due to its riverine climate. Forest cover, flora, and crops were gradually overtaken by concrete structures, leading to severe waterlogging and reducing the soil's natural water retention capacity. Today, the 150-acre Zinda Park, home to over 25,000 trees, serves as a Nature-based Solution (NbS). Its trees act as carbon sinks and moisture generators, while five large interconnected retention ponds smooth out monsoon rain peaks to prevent waterlogging and erosion. Moreover, the local community organization, Agropathik Palli Samity, allocates park earnings to a disaster fund supporting villagers affected by riverbank erosion. The central geographic and socio-economic issue is associated with the Zinda village, which is located in the Daudpur Union, Rupganj Upazila, Narayanganj District, Bangladesh. The site of the park is 37 km to the northeast of Dhaka, bordered by the Dhaka Eastern Bypass Road.28

37TOn the territory of the Purbachal New Town, which is being constructed by RAJUK on the 6150 acres, a state-owned enterprise has been allocated for the development of the park. As for the central geographic and social issues, the territory of Zinda village is located on a low floodplain, which in the past was subject to seasonal flooding and erosion of the river banks. However, the main problem was the lack of public places, recreation areas, and multi-purpose and a shortage of employment opportunities for the local poor population, as well as places for leisure and work. The creation of the Zinda Park was able to solve the issue of insufficient public spaces while, the construction of the park provided jobs for the local people in its infrastructure. Finally, the wetland development of the park’s territory has made it possible to restore the ecological balance and provide the local population with ecotourism. Protecting the wetland and river ecosystem is essential for both the environment and local residents. Without proper action, the area risks losing its natural carbon sinks, healthy ecosystems, and traditional rural culture. A fair compromise between city planners and conservation groups can prove that nature- based solutions work in practice. Keeping the park saves over 25,000 trees and five retention lakes, which are crucial for preventing monsoon flooding. At the same time, supporting this community-led effort protects local businesses, preserves village culture, and ensures displaced families keep access to vital emergency services like health care and education. Nature-based solutions used by Zinda Park are incorporating the process of ecological restoration alongside the creation of a low-carbon built environment to ensure long-term societal and environmental benefits. Firstly, to tackle the threat of deforestation and urban warming, the park’s management took the initiative by planting more than 20,000 to 25,000 native and medicinal plants to create a microclimate of biodiversity and to cool the surrounding area. Secondly, to solve the water management issues, the managers have constructed five interconnected retention lakes to stock the excess water from the monsoon season, preventing floods and underground water pollution and reducing the risks of soil erosion. Thirdly, the community ensured that the built environment was constructed using bioclimatic and vernacular designs with customized facades made of bricks that promote cross-ventilation and natural lighting, thereby eliminating the need of artificial climate control. Lastly, a community-based organization has been formed to manage the revenues from the park to continue the afforestation activities and to tackle the threat of disaster, as the profits can be used to offset the damage caused to the locals who lose their properties and farmland alongside the river banks. This assignment examines how a self-organized rural community created and manages Zinda Park in Narayanganj a 33-acre eco-park built on former fallow land to fight aggressive urban sprawl, environmental damage, and social isolation. Using social entrepreneurship and nature-based solutions, the park's interconnected lakes and forests restore local biodiversity, lower extreme temperatures, and prevent severe flooding. The research also highlights the social impact of this bottom-up development, showing how eco-tourism revenue directly funds vital community infrastructure like schools, libraries, clinics, and disaster response for riverbank erosion. Finally, it explores the governance conflict between local community preservation and the government's urban expansion plans (RAJUK's Purbachal New Town Project), using Zinda Park as a key example of rural resistance aimed at protecting local culture and natural resources. Background and Context Zinda Park's low-lying location near the Shitalakhya and Balu rivers makes water management a huge factor, especially during heavy monsoon rains. Fortunately, the local climate and soil naturally support rich vegetation, gardens, and farming. In a natural setting, plants, soil, and wetlands slow down, absorb, and temporarily store rainwater.

38But rapid urbanization around Dhaka is replacing these natural buffers with roads and buildings, changing how water moves and increasing pressure on the land. By preserving a large green space filled with trees, gardens, and lakes, Zinda Park creates vital "green and blue" infrastructure. It does far more than offer a spot for recreation it keeps essential natural ecosystems working even as the surrounding area continues to develop rapidly. Flooding and rapid urbanization are two major challenges in the area. Heavy monsoon rainfall, combined with nearby rivers, causes waterlogging and flooding, while riverbank erosion destroys land, homes, and agricultural areas. Urbanization exacerbates these risks. Filling wetlands and open spaces reduces natural water storage, while roads and buildings block soil absorption. Additionally, tree removal increases local temperatures and degrades wildlife habitats. Development is necessary, but problems arise when it ignores natural systems. Zinda Park offers a different approach by preserving green spaces and water bodies to maintain essential environmental functions. Environmental problems hit several groups hard, especially local residents. Flooding and land erosion destroy homes, roads, and farmland, wiping out income for family’s dependent on agriculture. The environment suffers as well, with clearing plants and changing land use wiping out habitats for local wildlife, birds, and aquatic life. While urban expansion brings new jobs, roads, and businesses, it also puts heavy pressure on natural resources. Zinda Park offers a practical middle ground by creating jobs and tourism opportunities without destroying the ecosystem. Importantly, revenue from the park helps fund local schools, health care, and disaster relief, tying environmental protection directly to community well-being. Previous studies describe Zinda Park as a community-based eco-park driven by local participation. This case is especially relevant given Bangladesh's rapid urbanization around major cities like Dhaka, where growing infrastructure demands threaten essential wetlands, agricultural land, and green spaces. Bangladesh's National Adaptation Plan (2023–2050) emphasizes ecosystem-based approaches and climate-resilient development principles core to Zinda Park. Studying the park demonstrates how Bangladesh can balance development with preserving natural systems to manage climate and disaster risks. What is the Nature-based Solution of Zinda Park Zinda Park's Nature-based Solution (NbS) combines several natural and community-based features: Vegetation: Over 25,000 trees, gardens, and plants provide shade, enhance aesthetic value, create wildlife habitats, and store carbon. Artificial Lakes: Five lakes hold water and support aquatic species, with two designated for fisheries to generate economic value. Interactive Ecosystems: Open spaces where vegetation and water meet foster high biodiversity. Eco-friendly Infrastructure: Buildings incorporate natural lighting and ventilation to maintain the environmental focus. Community Ownership: Developed through local participation rather than external imposition, residents maintain and manage the park. This long-term community stewardship driven by direct social and economic benefits ensures the ecosystem's sustainability. Zinda Park is located in Daudpur Union, Rupganj Upazila, Narayanganj District. It is close to Purbachal and around 37 kilometres from Dhaka. This location means the park is surrounded by a landscape that is becoming increasingly urbanized. Therefore, its green space becomes even more valuable as development continues.

39The main idea behind developing Zinda Park was to preserve greenery and create a better environment for the local community. The park was also intended to provide facilities that were not easily available to residents, including recreational areas, educational opportunities and healthcare facilities. In this sense, the park was not created only for visitors. It was also created for the people living in the community. That is one of the reasons why I think it is a useful example of an NbS. The project tries to solve more than one problem at the same time. It protects nature while also improving people's life. There are several groups that benefit from Zinda Park.Local residents benefit from employment and income-generating opportunities. They also benefit from the social services and community facilities connected to the park. Visitors benefit from having access to green spaces, gardens, lakes and recreational areas. Children and students can benefit from educational opportunities and a safe place to spend time.The environment benefits because trees, vegetation and water bodies provide habitats for different species. The wider community can also benefit because some of the income generated by the park has been used to support schools, scholarships, healthcare and people affected by floods and river erosion. This is quite different from a typical commercial park, where most of the focus is on attracting visitors and making money. In Zinda Park, the community is supposed to receive part of the benefit as well. Zinda Park contains several connected ecosystems. The first is the terrestrial ecosystem. This includes the trees, gardens, grass and other vegetation. The second is the freshwater ecosystem created by the lakes. These water bodies provide habitats for fish and other aquatic organisms.The third is the area where land and water meet. These transitional areas can be useful for birds, insects, turtles and other organisms. The park also has significant plant diversity. Different sources give different numbers for the total number of plant species and trees, so the exact figures should be treated carefully. Nevertheless, it is clear that the park contains substantial vegetation.This combination of land and water is one of the reasons why the park can provide several ecosystem services at the same. The park addresses the environmental problems in several different ways.First, it protects green space in an area that is experiencing urban development.Second, its trees and vegetation support biodiversity and provide shade.Third, the lakes provide water-storage areas and aquatic habitats.Fourth, the park creates a place where the community can interact with nature.Finally, the community-based management model creates an economic reason to protect the park.However, it is important to be realistic about what the available evidence can prove. The park clearly has these environmental features, but there is not enough detailed scientific monitoring to say exactly how much the park reduces flooding, lowers temperatures or increases groundwater recharge.Therefore, these should be described as potential benefits rather than exact measured results.

40Evidence of Effectiveness and Impacts One of the most visible achievements of Zinda Park is the preservation of a large green area in a rapidly developing region. The park contains many trees and plants, and its gardens and open areas provide habitats for different species. This is particularly valuable in an area where natural land is under pressure from development. The five lakes are also environmentally important. They provide aquatic habitats and contribute to the park's overall ecological diversity. Some of the lakes are also used for fishery, which means they provide both environmental and economic benefits. The community has also been involved in tree planting and reforestation. The recognition received for tree-planting activities in 2006 shows that these efforts have had wider recognition. However, one limitation is that there is not enough long-term scientific data showing exactly how the environment has changed because of the park. For example, we do not have detailed measurements showing how much carbon the trees store, how biodiversity has changed over time, or how much the lakes reduce flooding. So, the environmental benefits are quite clear, but their exact size is difficult to measure from the available evidence. The social impact of Zinda Park is probably one of its strongest aspects. The local community has been involved in developing and maintaining the park. This involvement has helped create a sense of ownership. The park has also contributed to education and social welfare. Revenue has been used to support scholarships, schools, libraries and other community institutions. Healthcare is another area where the park has contributed. Land has been provided for a community clinic. The park has also supported people affected by flooding and riverbank erosion. These activities show that the park is not completely separate from the problems faced by local residents. Instead, some of the income generated from the park is used to help address those problems. According to the available material, the community was donating around BDT 0.5 million per year to social welfare activities at the time of the study. This provides an example of how the park's income can be connected to community development. Zinda Park also has an interesting economic model. Tourism creates income, and some of that income is used to maintain the park and support the community. At the time of the study, around 200–350 people were reported to visit the park each day, and the entrance fee was BDT 150 per person. The park also generated income through other activities, such as car parking and renting space for a tea stall. According to the available information, car parking generated around BDT 0.1 million per year, while the tea-stall rent was around BDT 5,000 at the time. These amounts may seem small compared with large commercial projects, but the important point is how the money is used. The model can basically be understood as: Visitors → Income → Park Maintenance and Community Support → Environmental and Social Benefits This makes the park different from a project where all revenue simply goes to private profit. The economic benefits are also connected to employment. Local people can earn money through activities related to the park, which can make the project more valuable to the community. Zinda Park helps the area withstand disasters through its natural features and community design. Its five retention lakes collect excess water during heavy rain to prevent flooding, while its dense trees provide shade that lowers local temperatures during heatwaves. Beyond these physical benefits, the park's true resilience lies in how it brings people together and supports the local community. The community's support for people affected by floods and river erosion is another form of resilience. When people experience a disaster, having a community network that can provide financial or social assistance can make recovery easier. This is one of the things I find particularly interesting about the park. It combines environmental resilience with social resilience. However, once again, there is not enough quantitative evidence to say exactly how much the park reduces flood levels or temperature. More monitoring would be needed to prove these impacts.

41There are several signs that Zinda Park has been successful. The park contains a large amount of vegetation and many different plant species. Tree planting and maintenance activities have continued over time. The fact that people continue to visit the park also shows that it has become an important recreational space. Its continued connection to education, healthcare and community activities is another sign of its social importance. However, the available monitoring data is not as strong as it could be. For example, there is limited long-term information about carbon storage, biodiversity population changes, groundwater recharge and actual flood reduction. This does not mean the park is unsuccessful. It simply means that some of its benefits have not been measured scientifically in enough detail. In the future, collecting this data would make it much easier to demonstrate the value of Zinda Park as a Nature-based Solution. IUCN NbS Self-Assessment Criterion 1: Societal Challenges Assessment: Strong Pass Zinda Park clearly responds to several societal and environmental challenges. These include the loss of green space, urbanization, biodiversity loss and the lack of recreational and community facilities. The fact that the park developed through community participation is especially important. It means that the project was connected to the needs of local people rather than being designed only by outside organizations. Criterion 2: Design Grounded in Scale Assessment: Moderate Pass The park includes trees, gardens, lakes, open spaces and community facilities. These different features work together. However, the park is still somewhat isolated from the wider landscape. The surrounding development, especially around Purbachal, continues to change the natural environment. Because of this, the park would be stronger if it were connected to surrounding wetlands, drainage systems and other green areas. Criterion 3: Biodiversity and Ecosystem Integrity Assessment: Moderate Pass The park clearly provides valuable habitat through its trees, gardens and water bodies. The lakes support aquatic life, while the trees and vegetation provide habitat for birds and insects. However, biodiversity monitoring is limited. We do not have enough long-term data showing how species populations have changed. Because of this, the park performs well in terms of creating habitat but less strongly in terms of scientifically monitoring biodiversity. Criterion 4: Economic Feasibility and Financial Viability Assessment: Moderate Pass The park has developed a model where tourism income supports maintenance and community activities. This is a major strength because it means the park does not rely completely on outside funding. However, more detailed financial information would be useful. Having clear information about annual income, maintenance costs and community spending would make the system more transparent.

42Criterion 5: Inclusive Governance and Equity Assessment: Strong Pass Community participation is one of the strongest parts of Zinda Park. Local residents have been involved in the development and management of the park, which gives them a sense of ownership. However, participation should continue to expand so that different groups within the community have a voice. Women, young people, elderly people, people with disabilities and lower-income residents should all have opportunities to participate. Criterion 6: Balancing Goals and Safeguards Assessment: Moderate Pass The park tries to balance tourism, environmental protection and community needs. There are rules and management practices designed to reduce environmental damage. However, the park could benefit from a more formal environmental management system, including regular monitoring of waste, water quality and ecological conditions. Criterion 7: Adaptive Management Assessment: Pass The fact that the park has continued to develop over many years shows that the community has been able to adapt. Local knowledge plays an important role in decision-making. However, the project could become even stronger by combining local knowledge with more scientific monitoring and data. Criterion 8: Mainstreaming and Sustainability Assessment: Moderate Pass Zinda Park provides a useful example of community-led environmental management and eco-tourism. Its experience could be useful for other communities in Bangladesh.However, the long-term sustainability of the park depends partly on what happens around it. If surrounding urban development continues without considering the park's environmental role, maintaining its benefits may become more difficult. Identifying the areas where the NBS will perform better The primary areas for improvement and actionable steps to strengthen them include the following which can make ground work better: 1.Formalizing Environmental Safeguards (Criterion 6): While Zinda Park successfully enforces practical on-the-ground rules (such as banning outside food to curb litter and using low-impact local construction materials like exposed terracotta brick), it lacks a formalized, institutionalized environmental management system (EMS). 2.Upgrading Data-Driven Adaptive Management (Criterion 7): Management decisions over the past 35+ years have been organic, relying heavily on community consensus, local intuition, and trial-and- error to navigate shifts (including past bureaucratic land challenges with regional planning agencies like RAJUK). 3.Broadening Systemic Landscape Integration (Criterion 2): Operating as a localized 150-acre sanctuary, Zinda Park functions smoothly within its immediate borders, but its ecological design is somewhat isolated from the rapidly developing urban surroundings of the Purbachal New Town megaproject.

43The overall quality and sustainability of The Zinda Park The IUCN Nature-based Solutions (NbS) Self-Assessment for Zinda Park provides a clear blueprint of the initiative's strengths, structural vulnerabilities, and long-term viability. Zinda Park demonstrates exceptionally high social and governance quality, with genuine community ownership, social equity, and localized governance emerging from its grassroots construction by the Agrapathik Palli Samiti rather than any corporate or top-down government entity. Its environmental achievements are equally proven: barren, low-yielding land has been transformed into a thriving, multi- layered sanctuary of over 10,000 trees across 250 species, delivering clear biological net-gains. The quality deficit lies not in intent or execution but in formal documentation and scientific standardization— having evolved organically through trial and error over more than 35 years, the park lacks the rigorous data telemetry, baseline carbon accounting, and institutionalized environmental impact assessments expected of modern corporate or institutional NbS projects. The park's sustainability rests on strong financial and socio-cultural foundations but faces external vulnerabilities. Its self-sustaining model, powered by nominal visitor fees that directly fund maintenance, local schooling, and community welfare, gives it high financial durability compared with projects dependent on unstable grants or state subsidies, while shared economic and recreational benefits have fostered deep-rooted cultural protection, demonstrated by successful historical resistance against bureaucratic displacement. The primary threat is structural isolation and institutional friction: operating within the footprint of the Purbachal New Town megaproject managed by RAJUK means long-term survival depends on continuous legal recognition and harmonious coexistence with regional land-use policies, and without formal landscape integration and institutionalized climate risk planning, unexpected peri-urban pressures could threaten its borders. In conclusion, the assessment reveals that Zinda Park is a world-class model of organic, community-led ecological restoration, scoring exceptionally well on human-centric and biodiversity criteria. However, to transition from a localized eco-park to an internationally certified standard-bearer for Nature-based Solutions, it must bridge the gap between grassroots intuition and formal, data-driven environmental management Critical Evaluation of Zinda Park Zinda Park has several important strengths. The first is community participation. The involvement of local people gives the project a strong sense of ownership. The second is its greenery. In an area experiencing rapid urbanization, maintaining a large green space is valuable. The third is the presence of the five lakes. These water bodies provide aquatic habitats and can contribute to water retention. The fourth is the connection between tourism and community development. Income from the park has been used to support education, healthcare and social welfare. Finally, the park combines environmental, social and economic benefits instead of focusing on only one objective. That combination is what makes it particularly interesting as an NbS. At the same time, the park has some weaknesses. One possible issue is visitor pressure. If too many people visit the park, there could be more litter, noise, congestion and disturbance to wildlife. Accessibility could also be improved. Some pathways or facilities may not be convenient for elderly visitors or people with disabilities. Another issue is the park's location. Although being close to Dhaka creates opportunities for tourism, it also means the park is surrounded by rapid development. The biggest limitation is probably the pressure from urbanization. If the surrounding natural environment continues to disappear, the park could become increasingly isolated.

44Urbanization is likely to remain one of the biggest challenges. As more development takes place around the park, there may be pressure to use land for buildings, roads and other infrastructure. Land acquisition and development pressure have already been concerns. Financial sustainability is another challenge. The park needs enough income to maintain its facilities, but increasing commercialization could also damage the environmental qualities that make it special. This creates a difficult balance. The park needs enough visitors and revenue to survive, but it should not become so commercialized that it loses the natural environment and community character that made it successful in the first place. Even though Zinda Park provides many benefits, it can also create some unintended problems if it is not managed carefully. The first is tourism pressure. More visitors can mean more income, but it can also mean more waste, noise and disturbance. The second risk is overdevelopment inside the park. For example, building more restaurants, parking spaces or entertainment facilities could attract more visitors, but it could also reduce vegetation and disturb wildlife. The financial model is another possible risk. Because the park receives income from visitors, a major reduction in tourism could affect the money available for maintenance and community services. The lakes also require maintenance. Problems such as silt accumulation, stagnant water or invasive plants could reduce their ecological value. There are also governance risks. For Instance, the park becomes more economically valuable, it becomes increasingly important to ensure that decisions are transparent and that the benefits are shared fairly. Finally, development outside the park could affect its environmental conditions. Changes in surrounding drainage, groundwater and water quality could eventually affect the park even if the park itself is well managed. Trade-offs Between Environmental, Social and Economic Objectives Zinda Park illustrates that environmental, social, and economic objectives frequently conflict, producing clear trade-offs. Visitor revenue funds maintenance and community initiatives, yet excessive crowds generate waste, noise, and environmental strain. Similarly, adding parking, food stalls, or facilities boosts revenue but consumes natural land, and raising entrance fees increases income while excluding lower-income local residents. Management must therefore balance these priorities rather than maximize profit or visitor volume. Recommended strategies include setting visitor limits based on environmental capacity, offering discounted entry for local residents, and reinvesting tourism revenue into conservation and community development rather than unnecessary commercial expansion—in other words, the park should earn money from nature without destroying the nature that attracts people to it in the first place. Conclusion Zinda Park is a strong example of a Nature-based Solution, showing how environmental protection and community needs can work together in a rapidly urbanizing area. Surrounded by rapid development, flooding, erosion, and habitat loss, the park preserves critical greenery and five lakes that create wildlife habitats, store carbon, provide shade, and hold excess water during heavy rain. What makes it special is its community-driven approach: local residents played a major role in creating and managing the park, and because they directly benefit from it, they have a strong reason to protect it. Beyond environmental benefits, the park generates income through tourism and funds essential social services, including education, healthcare, and local welfare programs—proving that nature and human development do not have to be at odds.

45However, the project has limitations. There is little scientific data measuring its exact impact on flood reduction, temperature control, carbon storage, or biodiversity, and regular monitoring of rainfall, groundwater, and wildlife would help prove its true environmental value. Rapid urban expansion around Dhaka and the nearby Purbachal project threaten local drainage, groundwater, and land availability, so protecting the park requires cooperation from government agencies and urban planners, not just local management. Community decision-making must also actively include women, youth, low-income families, elderly residents, and people with disabilities so benefits are shared fairly, while tourism— though a vital revenue source—must remain sustainable rather than chasing sheer visitor numbers. Ultimately, Zinda Park demonstrates that effective climate solutions do not always require massive government funding or high-tech systems; they can grow organically from local communities, and while there is clear room for improvement in scientific monitoring, inclusive governance, and protection from surrounding development, the park serves as a valuable, practical model for community-based climate resilience across Bangladesh. References Ahmed, J. U., Hoque, S., Rubaiyat-i-Siddique, & Khan, N. A. (2016). Zinda Park: Rural community eco-park complex in Bangladesh. Vision: The Journal of Business Perspective, 20(4), 380–395. https://doi.org/10.1177/0972262916671469 International Union for Conservation of Nature. (2020). Ensuring effective Nature-based Solutions. IUCN International Union for Conservation of Nature. (2020). IUCN Global Standard for Nature-based Solutions: First edition. IUCN International Union for Conservation of Nature. (2025). Applying the IUCN Global Standard for Nature-based Solutions™. IUCN Govt's bid to take over Zinda Park protested. The Daily Star. https://www.thedailystar.net/govts-bid-to-take-over- zinda-park-protested-19527 Ministry of Environment, Forest and Climate Change. (2022). National adaptation plan of Bangladesh (2023–2050). Government of the People's Republic of Bangladesh. https://moef.gov.bd/

6 A NbS Study in Miyawaki Forest, Diabari. MD. Tawsif Reza, Mohammad Sadiqur Rahman, CM NoorAbstract Bangladesh's capital city, Dhaka is one of the most overcrowded cities in our world. The unstoppable and unplanned urbanization has led our beloved city to a severe environmental crisis, with the amount of healthy vegetation cover reducing by an astounding 88 percent between 1989 and 2020 and loss of 185 hectares of tree cover in 2010-2022 alone. This ecological decline represents itself in various components interacting with each other: the exacerbation of urban heat islands, a decline in air quality, the loss of biodiversity, and exposure to climate-related emergencies. The vulnerable urban populations that include rickshaw pullers, street vendors, construction workers and schoolchildren are disproportionately impacted by these problems as they experience the increased temperatures and pollution.The Dhaka North City Corporation (DNCC), in reaction to this dire environmental situation, has launched an unprecedented project building a Miyawaki forest in Diabari, Uttara. The work is the biggest urban forestry project in Bangladesh employing the Miyawaki technique of afforestation, a specialized form of afforestation technique invented by a Japanese botanist, Akira Miyawaki, during the 1970s. The Diabari Miyawaki forest seeks to become a densely planted forest, a multi-layered, self-sufficient 2.60- acre green city forest, where around 53,400 trees (250 species of plant) will be planted. This nature- based solution (NbS) term paper explores Diabari Miyawaki forest as a solution to urban environmental problems of Dhaka. This paper explores the following in accordance with the IUCN Global Standard for Nature-based solutions framework; the environmental issues that the project is solving; its design and application; the multi-dimensional effects it has; and its strengths, weaknesses and replicability. Through the critical analysis of this innovative project, the paper seeks to add to the knowledge of NbS efficacy in highly populated urban environments and guide future greening policies of urban outlines in Bangladesh and other developing countries. Keywords: Miyawaki Forest; Diabari; Nature-Based Solutions;Department of Disaster Management and Environmental Studies, Brac University, BangladeshIntroduction Dhaka, located on the banks of the Buriganga River, faces severe environmental challenges driven by unplanned and rapid urbanization. Home to over 20 million people, the city struggles with an acute shortage of land for traditional parks and green spaces, and its low-lying floodplain topography has been largely covered by concrete and asphalt. These surfaces store and slowly release solar energy, creating an urban heat island effect that pushes city temperatures far above those of the surrounding countryside. The Bangladesh Meteorological Department reports a dramatic rise in average temperatures over the past thirty years, evidenced by extreme heat events such as the June 2023 school closures and the April 2024 heatwave that reached 41.5°C and shut down all educational institutions nationwide for seven days.28

46The Bangladesh Meteorological Department reports a dramatic rise in average temperatures over the past thirty years, evidenced by extreme heat events such as the June 2023 school closures and the April 2024 heatwave that reached 41.5°C and shut down all educational institutions nationwide for seven days. Dhaka is also among the world's most polluted cities, with brick kilns contributing roughly 13 percent of Bangladesh's air pollution alongside vehicle emissions, construction dust, and factories, causing respiratory and cardiovascular illness and premature death. Healthy vegetation cover fell from 17 percent in 1989 to just 88 percent in 2020 (as stated), driving out native flora and fauna and weakening the city's ecological resilience, while unplanned construction, encroachment on water bodies, and inadequate stormwater systems have degraded natural drainage, making monsoon flooding increasingly likely—especially for low- income slum residents. The residents most vulnerable to these crises include the marginalized urban poor in informal settlements, outdoor workers such as rickshaw pullers, street vendors, and construction workers, and children and students, whose education is disrupted by heatwaves and whose developing respiratory systems are especially susceptible to air pollution. The Diabari Miyawaki forest aligns with several national and international policy frameworks. Bangladesh's National Adaptation Plan identifies urban afforestation as a priority for building climate resilience, while the Nationally Determined Contribution pledges to expand tree cover to between 22.37 and 24 percent by 2030. The current administration's election manifesto promised to plant 250 million trees within five years, create a digital tree monitoring app, and impose a centralized measurement, reporting, and verification system; the World Bank predicts Bangladesh could earn up to USD 1 billion annually through carbon credit markets, achievable only with location-specific sequestration data from projects like the Diabari forest. The DNCC has proposed planting 50,000 trees in the first year with a goal of 500,000 over five years. Despite this favorable policy environment, analysts note that these commitments lack detailed implementation strategies and monitoring frameworks, leaving a gap between political ambition and on-the-ground results. The Miyawaki method itself—developed by Japanese botanist Dr. Akira Miyawaki—creates dense, native, multi-layered forests that become self-sustaining after two to three years, based on three principles: selecting native species suited to local soil and climate, high-density planting of three to five saplings per square meter to replicate natural forest regeneration and accelerate growth through competition for sunlight, and intensive early care including watering, weeding, and observation during the first two to three years. The Diabari Miyawaki forest, Bangladesh's largest such project, is located at Uttara, Diabari, and was launched on 18 May 2026, covering about 2.60 acres of priority green belt land. Planting is planned in three stages: Phase 1 ran from late November 2025 to January 2026 and saw 14,000 trees planted; Phases 2 and 3, launching in May 2026, will add some 39,400 more trees; and the whole project is expected to be finalized in December 2026 with a total target of 53,400 trees. Nearly 250 native species are included—fruit- bearing trees, flowering species, medicinal species, timber trees, ornamental varieties, conifers, shrubs, and bushes—creating a viable ecosystem to sustain original wildlife and pollinators. Soil preparation was extensive, with vermicompost, cocopeat, bone meal, rice husk, organic fertilizer, and liquid nutrients added to enhance water retention and biological quality; landscapist Arham Ul Haque Chowdhury stressed that soil preparation is the most significant aspect of the process, since with good soil the trees take care of themselves. Biophilic design and biomimicry feature artificial mounds for natural drainage, winding paths, and lakeside foot walks, inspired by the Japanese concept of Shinrin-yoku, or forest bathing, which treats forests as a resource for physical and mental health as well as ecological value. The project involves numerous government, private, and voluntary partners, including the Forest Department, Shakti Foundation, Green Savers, Green Voice, Brighters, Youth Foundation of Bangladesh, OAB Foundation, and the Youth Society for Environment and Development Organization, with Arham Ul Haque Chowdhury as technical assistant and Professor Dr. Ahmad Kamruzzaman Majumder and Rawfa Khanam on the task force analyzing air quality and policy.

47The forest addresses Dhaka's urban environmental problems in several ways: thick vegetation provides cooling through evapotranspiration and can lower ambient temperature by up to 5°C, mitigating the heat island effect; trees capture at least 15 percent of airborne particulates, with filtering capacity enhanced by the multi-layered canopy; fast-growing Miyawaki forests can sequester as much as 60 kg of carbon per square meter; native species and multi-layered structure support birds, insects, and other wildlife, enhancing biodiversity 18 to 20 times compared with conventional plantations; dense tree cover improves water absorption and reduces surface runoff and urban flooding; and the Shinrin-yoku approach recognizes psychological benefits including stress reduction, mood improvement, and cognitive enhancement. Evidence and Impacts The environmental effects of the Diabari Miyawaki forest can be evaluated by analyzing its touted gains as well as past data of other Miyawaki initiatives. It is indicated that multi-layered and thick Miyawaki forests have the potential of a reduction of ambient air temperatures to a minimum of 5 degrees Celsius, absorption of 15% of airborne particulate material and a rate of carbon seizure of 60 kg in a square meter. Furthermore, similar Miyawaki projects in Japan as well as in the Netherlands and India have been reported to have survival rates of almost 90% of the trees and an increase of birds and other insects that pollinate it. Our Diabari Miyawaki project is still underway and has a long way to go to develop even further, but these signs indicate that it has a great potential to have a positive impact on the environment. Md Saeedi Karim, the DNCC arboriculture officer, confirms that the survival of trees, their growth rate, and environmental change are being observed every now and then. Nevertheless, diarrhea is limited by lack of baseline data on the pre-existing vegetation cover, biodiversity, and the environmental conditions at the Diabari site to empirically assess the specific environmental impacts of the project. Goa (preliminary monitoring efforts) is a reflection of these challenges. It is not only just a forest, but the Diabari Miyawaki forest is created as a community asset that allows a community to engage in healthcare and well-being. The choice of the pathways and Shinrin-yoku spaces in the project presupposes that this was done with a purpose to provide the city inhabitants with recreational opportunities. The DNCC Administrator, Md Shafiqul Islam Khan has highlighted the mentally invigorating nature of the project location, and said that this kind of green areas would certainly have a massive positive impact and boost the mental state and physical health condition of city living people. Possible educational effects are important. In 2025, comparative work by the Swedish University of Agricultural Sciences determined that children who participated in planting Miyawaki forests, had enduring stewardship attitudes that spilled over to their families. Student-planted forests lasted longer than individual student-received forests, indicating that community involvement in planting and monitoring facilitates better social sustenance to the long run. Similar educational and stewardship results could be created through the potential of the school's involvement in the Diabari project, which has not yet materialized. The design of the project also enables diverse individuals with diverse socioeconomic statuses to enjoy the better environmental conditions and enjoy the places of green cover. Nevertheless, certain statistics on community engagement, usage patterns and social outcomes are not available. Also, it is not explicitly stated how much marginalized groups like rickshaw pullers and street vendors have been factored in the design of the project and in its accessibility planning. Economic benefits can be evaluated at several levels. Directly, the project involves working with local laborers during construction and maintenance, creating jobs for people in the area, while the involvement of several NGOs and contractors has likely generated additional direct economic activity. Beyond these immediate gains, the forest delivers climate resilience and risk reduction by minimizing the economic losses associated with health impacts, productivity losses, and infrastructure damage through its ability to cool the city, improve air quality, and manage stormwater.

48Diabari's economic viability is further underscored by the World Bank's estimate of up to USD 1 billion in annual revenues from carbon markets in Bangladesh, with the verified carbon credits produced by the forest potentially creating an avenue for city income or corporate carbon offsets. Urban green spaces generally provide positive added value to surrounding property, which can lead to economic advantages for nearby neighborhoods; however, these benefits also raise equity issues if they help to gentrify or displace lower-income residents. Beyond property value, the Diabari Miyawaki forest delivers disaster risk reduction and climate resilience benefits on several fronts. As heatwaves grow more frequent and intense, urban cooling becomes increasingly important, and the expected 5°C drop in temperature would help safeguard vulnerable groups during extreme heat. Better soil water uptake and surface runoff control reduce urban flood risk, especially during heavy monsoon rainfall. Overall, the project serves as climate adaptation infrastructure that helps the city adjust to shifting climate conditions without relying on costly, high-energy technologies such as air conditioning. IUCN NbS Self-Assessment There is an IUCN Global Standard for NbS which provides guidance on the evaluation of whether an intervention is actually an NbS. The self-assessment tool addresses eight criteria relating to sustainable development and project management that are resilient. The Diabari Miyawaki forest is evaluated for each criterion. Criterion 1: Societal Problems and Concerns Assessment: Strong The Diabari Miyawaki forest acknowledges numerous issues for example: negative impacts on human health and wellbeing, decreasing disaster related risks, adaptation & mitigation due to climate change etc. It also includes urban heat reduction, carbon sequestration, flooding, heatwaves, air pollution, biodiversity loss etc. benefits of forest bathing. The intervention directly addresses actual environmental issues and priorities. There is good documentation of the societal challenge, including satellite imagery, meteorological data, and pollution monitoring data. Criterion 2: Design and Implementation at Scale Assessment: Adequate The project showcases the use of appropriate design principles such as the selection of appropriate native species, creating a multi-layered canopy structure, planting high density and preparing the soil. The implementation of 2.60 acres is a significant scale from an urban context. Yet it is a pilot project and is small compared to Dhaka's landmass. Long-term monitoring is needed to demonstrate the effectiveness of the project in meeting the following objectives. There is a need for longer term monitoring to provide evidence of effectiveness at this density and scale: pathways, water features and biophilic design elements point to thoughtful scaling. Criterion 3: Biodiversity Net-Gain Assessment: Partial The project will use 250 native species thereby contributing to the enhancement of biodiversity compared to traditional greening projects. However, there is no detailed biodiversity baseline data publicly available on the Diabari site, and verifying the net gain is challenging. The methodology indicates potential biodiversity improvement but the evidence of actual biodiversity improvement will need monitoring over time.

49Criterion 4: Economic Feasibility and Cost-Effectiveness Assessment: Adequate The soil preparation and planting phase of the project is quite demanding, and while the Miyawaki method may not be economically viable in the short term, its cost-effectiveness after establishment makes it a worthwhile investment. Carbon credit, avoided health cost, and property value improvements are among the potential co-benefits with potential positive cost benefit ratios. Detailed financial projections and economic analysis of this particular project are not well documented. Criterion 5: Inclusive Governance and Stakeholder Engagement Assessment: Partial The project is a joint effort between DNCC, various NGOs and private entities. The multi-stakeholder governance structure implies design processes that are inclusive. But there are few signs of local community and marginal group involvement. Its direct beneficiaries are the people of the city, and while it is unclear whether community involvement in decision-making is meaningful, it is clear that they are not. Criterion 6: Balance between Multiple Objectives Assessment: Adequate The project is designed to achieve environmental goals (cooling effects, biodiversity protection, reducing pollution), social goals (recreation, wellbeing), and economic goals (job creation, carbon market opportunity). Multiple functions are incorporated into the design, but trade-offs and prioritization among functions is not clearly documented. Objectives are set in a balanced way when ecological and recreational objectives are simultaneously pursued. Criterion 7: Adaptive Management Assessment: Partial Survival and growth monitoring of trees is ongoing, aiding adaptive management. But adaptive management plans are not necessarily documented in detail with clear triggers for action. Lessons are being captured from the project for future expansion, but formal adaptive management systems do not seem to be widely established. Criterion 8: Sustainability and Mainstreaming Assessment: Partial The project is supported institutionally by DNCC and is incorporated in the National tree planting targets. Political will and implementation of protection will be critical to sustainability. Potential for mainstreaming the Miyawaki approach, but not yet demonstrated policy integration at scale in the Diabari project. The greenbelt designation is an institutional commitment, borne by a significant risk of sustainability. The overall assessment of the Diabari Miyawaki forest is good at aligning with the IUCN Standard, especially regarding addressing societal challenges and design principles. There are a number of areas in need of improvement, however, such as documentation of community engagement, adaptive management systems, biodiversity baseline data, and sustainability protections for the long-term. The traffic light assessment identifies areas for improvement, and overall, the project appears to have the potential to be a genuine NbS. Strengths, Limitations, and Challenges The Miyawaki method's most striking strength is its speed: it can grow a functioning forest in urban space within two to three years, compared with the 15 to 20 years required by conventional afforestation a quick response that is key to solving Dhaka's environmental problems. The forest also delivers multi-layered benefits, serving climate, biodiversity, disaster risk, and human wellbeing in an interdependent way that creates synergies across sectors.

50Institutionally, the project is an innovative example of government, civil society, and private sector actors working together to realize urban greening on a multi-stakeholder basis. Once established, Miyawaki forests require little maintenance, keeping long-term costs and institutional burden low, and the design offers opportunities for community engagement, education, and stewardship as a "forest bathing" destination. At 2.60 acres, the forest is significant but small relative to Dhaka's urban area of more than 300 square kilometers, meaning it cannot solve the city's environmental crises on its own. The Miyawaki method also requires suitable soil and site conditions, so its use across Dhaka's varied settings may not always be appropriate. Baseline data and systematic monitoring of biodiversity, temperature, air quality, and carbon sequestration are not adequately publicly reported, and forestry experts have raised concerns about replicating the model across different soil types and climatic conditions, including in India. The foremost limit to scaling up is the availability of suitable land in Dhaka's densely built-up areas. Institutional will and continuity are equally fragile: political and administrative changes may jeopardize support for long-term projects, and Diabari's greenbelt protection is only as secure as the goodwill of institutions to implement it. While policy discourses on urban greening exist, detailed strategies are lacking— a Mongabay analysis revealed that Bangladesh's 250 million tree-planting target has no realistic implementation strategy—and Miyawaki forests demand substantial resources for soil preparation, saplings, and initial maintenance in a country with limited municipal budgets. Risks and unintended consequences are always possible, including equity concerns, since green space enhancements can raise property values and drive gentrification that pushes out lower-income communities if unmanaged, benefiting local people without reaching those on the community's fringes. Ecological risks also exist: excessive planting may cause competitive pressures or disease, dominant species can lower biodiversity benefits if the species mix is unmanaged, and homogeneity could result if only one restoration technique is used everywhere. Finally, uniform application of the Miyawaki method across different ecological zones without regard for local conditions could produce maladaptive outcomes. The Diabari forest's objectives involve trade-offs between environmental, social, and economic goals. Maximum ecological benefits are incompatible with social goals such as recreation and forest bathing, while monitoring complexity for the economic goal of carbon credit generation may divert resources from direct social benefits. Such competing priorities need to be addressed in a deliberate, transparent, and inclusive manner. Conclusion The Diabari Miyawaki forest is a possible innovative and 'Nature based Solution' (NbS) in addressing the present environmental issues in the city of Dhaka. The project showcases the capability of building dense native forests in small-scale urban settings to provide multidimensional benefits such as urban heat, air quality improvement, biodiversity, human wellbeing and climate resilience. There's much to be proud of in the project's construction: it's quick, sets many new faces as powerful spokespersons, is innovative in its approach, and a community asset in design. The IUCN assessment confirms a high degree of alignment with most of the criteria of the (NbS), especially on societal challenges and design quality. But there are restrictions and obstacles that need to be taken into account. The scale is still relatively small in Dhaka context in comparison to the vast environmental problems faced by Dhaka. All parties need comprehensive monitoring data to ensure environmental and social results are being achieved. There is potential to improve the capacity of community engagement processes. Long-term sustainability depends on institutional will and institutional protection, which are hard to be achieved in politically unstable situations.

51However, these constrains lessons to be learned and replicated in the Diabari forest. The project demonstrates that it is possible to overcome limitations in land use in the City despite the high population density by creating an effective cooperation between institutions and using the appropriate methodology and skills. It can be replicated in other schools, parks and available spaces in Dhaka city. The results of the studies in the Netherlands indicate that they can anticipate that these forests can be expected to survive at about 90%, and therefore have a degree of confidence in the method used. To scale, there are a number of conditions to fulfil. Firstly, the government should pay particular attention to effective monitoring systems, so as to foster confidence in impacts and lessons learnt through pilot projects. Secondly, planted forests must be safeguarded – and safeguarded to be legal rather than location of development. There must be community engagement and education in concert to serve stewardship and public interest. Furthermore, the method should be adaptable at a local level, recognizing that not all situations would be appropriate to the Miyawaki method. Lastly, equity protecting measures should guarantee that the benefits are distributed to vulnerable groups. Finally, the Diabari Miyawaki forest is a positive development towards greening Dhaka and making it climate resilient. The project makes an interesting nature-based solution case study to the densely settled and quickly urbanizing cities of the Global South. Policy makers, practitioners and researchers will need to closely monitor its development, changes, and comprehensive efficacy testing. If Bangladesh's effort of planting 250 million trees is scaled up, it will do a real transformation in Bangladesh's urban environment which will surely become the example for the region. The potential for this transformation lies in the Diabari forest, which remains in its early stages - as long as the institutions and society necessary for it to become a reality are maintained. Reference International Union for Conservation of Nature. (2020). Guidance for using the IUCN Global Standard for Nature-based Solutions: A user-friendly framework for the verification, design and scaling up of Nature-based Solutions (1st ed.). IUCN. https://doi.org/10.2305/IUCN.CH.2020.08.en International Union for Conservation of Nature. (2024). How to interpret your self-assessment results(Version01.02.2024).IUCN. https://nbs-sat.iucn.org/sites/nbs-sat.iucn.org/files/support/how-interpret-your- self-assessment-01022024.pdf International Union for Conservation of Nature. (n.d.). IUCN Global Standard for Nature-based Solutions. IUCN. https://iucn.org/our-work/topic/iucn-global-standard-nature-based-solutions International Union for Conservation of Nature.(n.d.) NbS Self-Assessment Online Tool. https://inbs.iucn.org/apply/nature- based-solutions-self-assessment/tool/ The Business Standard. (2026, August 19). Can Japanese-style pocket forests help Dhaka breathe?The Business Standard .https://www.tbsnews.net/features/panorama/can-japanese-style-pocket-forests-help-dhaka-breathe-1520646 Haider, M.J.(2026, August 4). Miyawaki forests can cool Dhaka, but only if we scale and protect them. The Daily Star https://online92.thedailystar.net/opinion/views/news/miyawaki-forests-can-cool-dhaka-only-if-we-scale-and-protect- them-4240356 New Age. (2026,August 11). Greening Dhaka. New Age. https://www.newagebd.net/post/opinion/309571/greening-dhaka Prothom Alo English. (2026,May18). DNCC launches Miyawaki urban forest in Dhaka. Prothom Alo. https://en.prothom.alo.com/environment/qfpuc6im9b Daily Observer. (2026, May 6). The Miyawaki method for a green Dhaka. Daily Observer. https://observerbd.com/news/575343 Daily Times of Bangladesh. (2026, May 17).DNCC launches country”s largest Miyawaki urban forest project. Daily Times of Bangladesh. https://tob.news/dncc-launches-countrys-largest-miyawaki-urban-forest-project/ Daily Observer. (2026, June 17). Tree plantation in Miyawaki method held in Patuakhali. Daily Observer. https://www.observerbd.com/news/575343 Sakib,M.A.A.(2026, May 6). The Miyawaki method for a green Dhaka. Daily Observer. https://observerbd.com/news/575343

7 Case Study of Sundarbans as a Nature Based Solution (NbS) Oishi Saha & Mastura Anjum PraptiAbstract Bangladesh lying delta coastline makes Bangladesh highly vulnerable to cyclones storm surges and rising sea levels. This assignment examines Sundarbans mangrove forest as a Nature-based Solution (NbS) for managing these risks. The study looks at how mangrove restoration reduces wave energy and storm damage prevents erosion stores large amounts of blue carbon and supports local livelihoods through fishing, honey collection and eco-tourism. Using IUCN NbS Self-Assessment framework Sundarbans NbS scores on integrated ecosystem benefits but shows weaker performance in financing, governance and long-term adaptive management. Overall the paper concludes that protecting and restoring Sundarbans is a cost-sustainable alternative, to artificial infrastructure though stronger funding, coordination and monitoring are needed to secure long-term success. Keywords: Shundarbans; Nature-Based Solutions;Department of Disaster Management and Environmental Studies, Brac University, BangladeshIntroduction Bangladesh is a riverine country with world's largest delta. Due to it's hazardous geographical loacation and low and flat trophography, where half of the land is elevated of less than 6 meters above the sea level, the climate of Bangladesh can be describrd as vulnerable. The mangrove Sundarbans is one of the largest forests on delta of Ganges, Brahmaputra and Meghna rivers on the Bay of Bengal. (ADB Independent Evaluation Department, 2015). For example, its funnel-shaped geographical situation, southern coast makes it susceptible to cyclones and storm surges, medium to high levels of soil salinity and risen sea level. The Sundarbans Mangroves ecoregion on the coast forms the seaward fringe having the delta of world's largest mangrove ecosystem, with 20,400 square kilometres. Though the Mangrove forests are not home to a great variety of plant, Sundarbans possess dominant Heritiera. Due to the geographical location, Sundarbans are endangered with severe storms, cyclones which are already mentioned. Therefore, architecture plays as natural buffer to an extend to stabilize the coastline and balance the environmrent. Background and Context Located in the Khulna, Satkhira, and Bagerhat districts of southwestern Bangladesh, the Sundarbans is the world's largest contiguous mangrove forest, serving as an interface between terrestrial and marine ecosystems. Due to its flat and low-lying topography, the region faces extreme climate risks such as sea-level rise, high salinity, riverbank erosion, and storm surges. However, this dense mangrove forest acts as a natural buffer, protecting coastal soil and shielding local communities from the impact of tropical storms.28

52The primary environmental and climate challenges facing the Sundarbans coastal region are frequent, powerful tropical cyclones (such as Sidr, Aila, Amphan, and Remal) and the resulting destructive storm surges. Furthermore, rapid sea-level rise is exacerbating coastal and riverbank erosion and causing severe saline water intrusion into agricultural lands and sources of potable water. (Bangladesh: Enhancing Coastal Resilience in a Changing Climate, 2022). The convergence of these natural disasters is destroying coastal infrastructure, damaging the natural protective barrier of mangroves, and placing the lives and livelihoods of local people at severe risk. (Gopal & Chauhan, 2006). Coastal communities, ecosystems, and vital economic sectors in coastal regions are being severely affected by the coastal environmental crisis. Marginalized populations in the coastal regions adjacent to the Sundarbans particularly fishers, wood and honey collectors, crab collectors, and small-scale farmers are the most severely affected. Frequent cyclones and storm surges destroy their homes and create an acute shortage of safe drinking water, agricultural sector. The natural habitats of numerous rare wildlife species and plantsincluding the Royal Bengal Tiger, deer, crocodile, birds etc. Severe threats due to reduced freshwater flow and excessive salinity. Furthermore, the continuous rise in sea levels is inundating large areas of the forest and damaging breeding grounds. (Gopal & Chauhan et al., 2006). Mangrove forests can store four to ten times more carbon in their soil and trees than typical tropical forests. Disasters linked to climate change and riverbank erosion cause an annual loss of approximately 1.3% of Bangladesh's GDP. The National Adaptation Plan (NAP 2023–2050) has set a goal to strengthen coastal natural defense systems to combat storm surges and disasters. (Bangladesh: Enhancing Coastal Resilience in a Changing Climate, 2022). Bangladesh Delta Plan 2100 (BDP 2100) Provides a long- term strategy for the protection of the southwestern coast and the conservation of mangrove forests. Description of the Nature-Based Solution Nature-based Solutions (NbS) are actions that involve the conservation, sustainable management, and restoration of natural or modified ecosystems to address various social and environmental crises, while simultaneously ensuring human well-being and biodiversity protection (IUCN, 2020; Seddon et al., 2020). The core of the proposed NbS for protecting the Sundarbans coastal region lies in community- based mangrove forest restoration and the creation of green belts. The pneumatophores (breathing roots) and root systems of mangrove plants reduce the speed and energy of ocean waves and trap coastal sediment, mitigating the severe impact of storm surges during cyclones and reducing riverbank erosion (Bangladesh: Enhancing Coastal Resilience in a Changing Climate, 2022). By slowing the natural flow of water, mangrove roots also help suspended sediment settle, naturally raising the elevation of coastal land and aiding adaptation to rising sea levels (Gopal & Chauhan et al., 2006). Beyond wave attenuation, mangroves support salinity and water control: revitalizing natural mangrove waterways and freshwater reservoirs helps maintain the groundwater level, thereby preventing saline water intrusion into adjacent agricultural lands (Gopal & Chauhan et al., 2006; Client Challenge, n.d.). The Sundarbans also delivers significant carbon sequestration, or blue carbon, storing 4 to 10 times more carbon in its soil and trees than typical tropical forests and playing a direct role in combating global climate change (Google Scholar, n.d.-b). Together, these functions make community-based mangrove restoration a multifaceted NbS for coastal protection, land building, water security, and climate mitigation. The NbS of Sundarban Mangrove green belts offer a cost-effective, self-sustaining barrier that dissipates wave energy and protects coastal communities, unlike traditional embankments that frequently failed during cyclones such as Sidr in 2007 and Aila in 2009. They also combat salinity intrusion and land loss from sea-level rise and coastal erosion, which damage agricultural land and safe water supplies, while sustaining fishermen, farmers, and coastal communities through fish habitat and seasonal income and reducing national spending on embankment repairs. Within this ecosystem, species such as sundori and gewa grow, and adjacent agricultural land depends on mangroves to prevent salinity contamination; thus the NbS addresses the identified problems by preventing cyclones and storms, preventing coastal erosion, and reducing salinity intrusion.

53Evidence and Impacts Restored and intact mangroves increase ecosystem integrity and biodiversity. Restoration trials involving multi-species in the Indian Sundarbans have led to better outcomes, including native fish and edible crab numbers, self-regeneration of seedlings, and other species, including horseshoe crabs (Nature India, 2024). Healthy mangrove traps large amounts of carbon in the above-ground biomass and sediments (blue carbon), with estimates of the Sundarbans aboveground carbon ranging between about 2325 Mg C ha -1 in some studies, and more in soils (Springer Nature, 2026). Under favourable conditions, the rates of sediment accretion of a few millimetres per year assist mangroves to keep up with moderate increases in sea level. Hydrological connectivity, which is achieved through re-excavation of canals, enhances the water quality, decreases localised flooding and helps to sustain fisheries and agriculture in the surrounding regions. Community restoration sites have been monitored and show progressive positive canopy cover and natural recruitment increases after initial planting has been successful. Societies located behind mangrove belts have reduced destruction of property, life, and assets in case of cyclones. Post-Cyclone Sidr empirical studies concluded that the mean measurable household monetary damage was approximately one-half in mangrove-covered villages in comparison to non-covered villages (Akber et al., 2018). It has also been reported that the death rates and house-damage rates are significantly lower in Sundarbans-guarded districts during major cyclones. Local labour (including women) is often used in restoration projects (to manage nurseries and plant, to raise short-term income, and to develop the skill to monitor ecology). Combination programs involving restoration and alternative livelihoods (eco-tourism, sustainable crab fattening, salt-tolerant agriculture or mangrove-product enterprises) lessen the strain on the remaining forest resources and enhance adaptive capacity. Mangroves have the potential to provide valuable ecosystem services. Regional analysis (NCAER, 2024) has estimated assessments of structural and regulating services (fish, storm protection, drinkable water, carbon restoration) ranging between a thousand US dollars per hectare/year. Less harm to embankments and infrastructure is reduced public and private money spent on rebuilding. Blue-carbon potential, opens up possibilities to achieve results-based finance or engage in carbon-market, but at scale, this has not been realised. 4.4 Advantages of Disaster Risk Reduction and Climate Resilience. The main DRR advantage is the dampening of storm surge and wave power that minimizes the chances of embankment failure and flooding inland. Field and modelling studies consistently observe the velocity reduction and large, but minor, decrease in the surge-height (Dasgupta et al., 2019). Belts of mangroves with engineered embankments are further advanced as hybrid approaches that offer more protection and less strength required of hard structures (and costs). The adaptive capacity of the mangroves in the event of a sea-level rise can also incorporate the capacity of the mangroves to accrete sediment and move to the landwards (where space is available), on longer time-scales. The co-benefits in climate-resilience include livelihood diversification other than extractive forest use and an increase in freshwater access by a reduction in salinity intrusion in a limited number of restored environments. The success is evidenced by comparisons of post-cyclone damage, remote-sensing evaluation of vegetation health, project monitoring reports of survival rates and area restored, and testimonials of the community. The weaknesses of the evidence base are that many small-scale plantings have not been monitored over time, outcomes are spatially heterogenous, and it is hard to causally attribute to a complex socio-ecological system. IUCN NbS Self-Assessment The IUCN Global Standard of Nature-based solutions has eight criteria and indicators. It self-assessed using the published evidence, project documentation and policy congruence of mangrove conservation and restoration in the Bangladesh Sundarbans (regional/national level).

Marking is made on a qualitative scale of Strong, Adequate, Partial or Insufficient, depending on the extent to which evidence available supports the fact that each of the criteria has been met. It is important to note that this evaluation is made on the basis of secondary sources and is not an alternative to an official project-level implementation of the official online tool. General evaluation analysis: Sundarbans mangrove NbS is performing well on its capability to meet clearly defined societal issues (Criterion 1), and deliver practical returns of biodiversity and protection (Criterion 3). It has to be landscape scale design and economically viable, with high ecosystem-service values and policy recognition. Partiality to adequate performance is exhibited in inclusiveness in governance, institutionalised multi-stakeholder, multi-scaled implementation in a densely populated, climate-sensitive delta, through institutionalised adaptive management, structured trade-off management, and the latter. The process of mainstreaming to national policy is not too new but continuous financing and coordination across borders are still in need of enhancement. The best support is on protection functions and long-term and standardised monitoring of all indicators in all sites of restoration. The evaluation shows that an NbS has a strong potential with high potential, and its overall quality and sustainability can be improved by a better co-management, ongoing monitoring, and diversified long-term finance. A note on evidence limitations is warranted: publicly available and peer-reviewed long-term survival and impact data for most small-scale or NGO-organized plantings are not available, so primary project data should be used when applying the official IUCN self-assessment tool to verify the NbS formally. The scores show that the NbS is satisfactory overall, with its greatest strength being the Integrated Systems Perspective (89%), while the main areas reducing the overall score are economic justification and financial feasibility (67%), equity and inclusive governance (67%), balancing goals and impacts (67% each), and adaptive management (67%). The fact that the NbS is not rated as Strong overall does not reflect a poor environmental concept; rather, the mechanisms the idea relies on economic, governance, and trade-off mechanisms, as well as long-term management—are not thoroughly supported and elucidated. Strengths, Limitations and Challenges The mangrove forest acts like a natural barrier as a vital bio-shield protecting millions in costal regions from dramatic cyclones, wave attenuation. Then it’s rich bio-diversity is a home to unique plants like (Sundari, Keora, Gewa, Golpata etc.) trees, birds, fishes and the iconic Royal Bengal Tiger. The socio-economic value also supports regional livelihood by supporting honey fishing materials to the local population. (Shahiduzzaman & Shahiduzzaman et al., 2026)54

55The climate hazards are rapid sea-level rise, coastal erosion and water salinity damaging the native trees. Then the wildlife poaching which is illegal hunting and trapping continuously to threaten endangered animals. Also the industrial chemical discharge, plastic waste and water pollution severely harm the ecosystem. Conclusion Mangrove conservation and restoration in the Sundarbans has high value, where multi-benefit Natural- Based Solution operates at regional to national scale. It serves as a vital eco-shield against cyclone, coastal erosion and climate vulnerability while delivering biodiversity, carbon storage and livelihood co-benefits.The UNESCO has initiated projects to estimate blue carbon stocks across various coastal ecosystems because the blue carbon ecosystems are vital as they have a net autotrophic ratio greater than one, due to the higher production of plant SOC than importance of these ecosystems for climate change mitigation efforts (Rahman et al. 2015). So we can say that, the Sundarbans shows as that nature itself can be one be our most cost effective and multi-benefit climate defenses, if we protect it as seriously as it protects us. References ADB Independent Evaluation Department. (2015, December 15). Bangladesh: Sundarbans Biodiversity Conservation Project. Asian Development Bank. https://www.adb.org/documents/bangladesh-sundarbans-biodiversity-conservation- project Islam, S. M. D., & Bhuiyan, M. a. H. (2018). Sundarbans mangrove forest of Bangladesh: causes of degradation and sustainable management options. Environmental Sustainability, 1(2), 113–131. https://doi.org/10.1007/s42398-018- 0018-y Adaptation climate promise climate risk management. (n.d.). National Adaptation Plan of Bangladesh (2023‐2050). https://www.undp.org/bangladesh/publications/national-adaptation-plan-bangladesh-2023-2050 Gopal, B., & Chauhan, M. (2006). Biodiversity and its conservation in the Sundarban Mangrove Ecosystem. Aquatic Sciences, 68(3), 338–354. https://doi.org/10.1007/s00027-006-0868-8 Bangladesh: Enhancing coastal resilience in a changing climate. (2022, September 12). https://www.worldbank.org/en/news/video/2022/09/12/bangladesh-enhancing-coastal-resilience-in-a-changing- climate Dasgupta, S., Sobhan, I., & Wheeler, D. (2017). The impact of climate change and aquatic salinization on mangrove species in the Bangladesh Sundarbans. AMBIO, 46(6), 680–694. https://doi.org/10.1007/s13280-017-0911-0 World Development Report 2021 team. (n.d.). World Development Report 2021: Data for Better Lives. https://wdr2021.worldbank.org/ Shahiduzzaman, & Shahiduzzaman. (2026, May 23). Sundarbans mangrove forest: Natural shield under pressure. Prothomalo. https://en.prothomalo.com/environment/jomu16d2ok. Roy, D. (n.d.). Sundarbans Day: Deer poaching surges in the Sundarbans. The Daily Star. https://www.thedailystar.net/environment/natural-resources/wildlife/news/sundarbans-day-deer-poaching- surges-the- sundarbans-3824161 Flood risk management. (n.d.). https://doi.org/10.1007/978-981-97-2688-2_21

8 Project Sonapahar: A Nature-based Solution for Industrial wasteland reclamation and Climate resilience in Chattogram, Bangladesh Anika Ibnat Sopnil & Lamia ZamanAbstract Project Sonapahar is a coastal forest restoration project in Mirsharai, Chattogram, Bangladesh. Mitigating the major impact on land degradation and biodiversity loss due to rapid urbanization, the project set up the first privately run pocket forest in this area on a degraded brick-kiln site. By using the Miyawaki reforestation method, over 120 native species were restored on 4,400 square feet of compacted soil. The IUCN Global Standards assessment found that the project was outstanding in terms of social needs. This work to overcome challenges, gain biodiversity and economic viability. There are also a number of areas of weakness such as landscape scale design, governance gaps and sustainability issues. The findings demonstrate that while pocket forests effectively cool microclimate and enable rapid restoration, they must integrate into broader regional planning to ensure long-term sustainability. Keywords: Project Sonapahar; Miyawaki method; IUCN Global Standards; Nature-Based solutions; Climate resilience; Land degradation; Pocket Forest; Mirsharai; ChattogramDepartment of Disaster Management and Environmental Studies, Brac University, BangladeshIntroduction Uncontrolled urbanization and the rapid growth of industry in the Global South are examples of environmental vulnerability, with infrastructure development frequently lagging behind that of provision of basic ecological safety measures. Climate sensitive countries like Bangladesh, rising terrestrial and coastal urbanization is an additional environmental risk (Seddon et al., 2020). Historically, the hill- cutting and fragmentation of forests and extensive soil degradation around the economic and commercial hub of the country, coastal Chattogram, has been the result of heavy industrial activities including steel factories, power plants as well as transportation routes (Alam, 2017; Hasan et al., 2015). This rapid rate of deforestation has impacted on some of the ecosystem services that are crucial to safeguard communities against climate change (Ahmed et al., 2021). Growing crises have given rise to an important way to mitigate disaster risks and adjust to the changing climate. Nature-based solutions are characterized by the International Union for Conservation of Nature (IUCN) as a series of actions to ensure protection, sustainability management and restoration of ecosystems that can effectively address society's challenges, that will benefit human well-being and biodiversity (IUCN, 2020). In a densely populated country like Bangladesh, where land is a scarce resource, some traditional techniques of large-scale reforestation may be restricted by competing land use in particular when land scarcity is a concern (IUCN Bangladesh, 2025).28

56Till now, one such effort is being made with the aid of Project Sonapahar, Mirsharai Upazila, Chattogram. It is planted on a former brick kiln site which is already devoid of nutrients and compacted and first privately funded a Miyawaki pocket forest in Bangladesh (Rahman, 2023). The Miyawaki method was developed by Dr. Akira Miyawaki, is a method of planting at high density to promote soil regeneration and the restoration of biodiversity (Miyawaki, 1999; Shirone et al., 2011). It is an urban climate resilient project, developed by environmentalists Delwar Jahan and Amjad Hossain. The project was awarded with the prestigious "Dwijen Sharma Poribesh Padak 2024" for its ecological restoration efforts by BRAC Bank, 2024. Case Focus The physical, ecological and socio-economic context of Mirsharai, Chattogram (Prothom Alo, 2023, 2024). To enlighten Miyawaki method technical implementation (soil engineering and species selection) in Project of Sonapahar, 2024. Assessments of empirical evidence on ecological, social and disaster risk reduction benefits of the project. Analyze the project in a systematic way based on the IUCN NbS Global Standard (International Union for Conservation of Nature [IUCN], 2020) 8 criteria. Background and Context Project Sonapahar is located in Mostannagar, Mirsharai of Chattogram in Bangladesh. Chattogram is endowed with a substantial number of hills, forests, rivers etc and natural resources but it has been under stress because of the intervention of human beings and changes in land use. The cutting of hills is considered as one of the serious environmental problems of the city of Chattogram and it causes deforestation and biodiversity loss, water logging and land sliding (Alam, 2017). Removing the vegetation from hilly lands can decrease the protective function of roots and vegetation cover and uncovered soil can be more responsible to erosion and instability (Alam, 2017). The high rainfall amount may also trigger the possibilities of slope problems in the area of Chattogram where environmental degradation and inappropriate land use are found (Ahmed et al., 2021). The project Sonapahar is a private project to restore the environment in the village of Mirsharai. The project established the first ever “Miyawaki” forest in Bangladesh on Sonapahar. The forest area is approximately 4,400 sq.ft. and there are approximately 120 species of forest plants in the forest (The Business Standard, 2026). Healthy vegetation can be directly related to the functioning of other parameters of the ecosystems such as biodiversity, habitat construction, soil protection and others, but it is not necessary to presume that a small forest has a certain value that equates to disaster risk reduction. We need more empirical evidence, monitoring data on the effectiveness of Sonapahar. This is in line with the IUCN strategy of assessing whether the NbS has an environmental and social impact (International Union for Conservation of Nature [IUCN], 2020). Hence, Project Sonapahar forest in Miyawaki practice is taken as a sample of NbS in this study. According to IUCN (2020), NbS are interventions involving protection, sustainable management or restoration of ecosystems to address societal challenges and support people and nature. This assignment aims to discuss the importance of forest in ecological restoration in the context of Sonapahar Miyawaki forest; highlight the advantages that can be derived from the forest and the constraints faced in forest restoration and sustainability. Description of the Nature-Based Solution “Project Sonapahar” According to IUCN, Nature-Based Solutions (NbS) are known as solutions that are inspired by nature and nature-based solutions, and that are designed to solve a problem. “Actions that safeguard and restore a natural or artificial ecosystem to meet society's needs in an effective and adaptive manner while ensuring both human wellbeing and biodiversity benefits (IUCN, 2020). Unlike grey infrastructure or engineering solutions which frequently use concrete infrastucture and a one size fits all

57design, NbS uses the ecosystem functions to provide a suite of ecological, social and economic benefits. The overall goal of an NbS is to tackle societal problems such as land degradation, climate change adaptation, urban heat islands, coastal vulnerabilities and to achieve a net benefit for biodiversity and local communities (IUCN, 2020). Project Sonapahar in Mirsharai, Chattogram was selected as the Nature-based Solution in the form of a Miyawaki forest. The Miyawaki method was devised by Japanese botanist Akira Miyawaki and involves growing a variety of species in small planting sites so they are densely interlaced and multi-layered. This approach is especially linked to projects of small size of forest restoration and urban and peri-urban greening. The area of a Miyawaki forest at Sonapahar is around 4,400 square feet and has around 120 species of native plants (The Business Standard, 2026). The project is relatively small in area but has a high diversity of planted species. Importance of using native plants: locally appropriate plants can potentially be more integrated into the surrounding ecosystem and can offer habitat and resources for local organisms. The main purpose of the project is to restore vegetation and biodiversity on degraded land. The reports on Sonapahar speak of an experimental forest and highlight its potential to prove the feasibility of establishing a dense and diverse forest in a small area (The Business Standard, 2026). In the Miyawaki method, an ecologically diverse 'plant mixture' is used, not a single species. Plants grow in different layers in the canopy from the bottom to the top. With time this may develop into a structure more akin to a natural forest than a single species plantation. Potential habitats, shade, protection of the soil, biodiversity support and carbon storage are possible services from the vegetation. They are representative of the broader goals of NbS, which are to tackle society's challenges whilst protecting and promoting biodiversity and human well-being (IUCN, 2020). The Sonapahar forest has been reported to have become denser, and so the long-term success of the forest is yet to be definitively determined as the forest is fairly young. The project's originator has also pointed out that the popular notion of the Miyawaki method growing trees rapidly does not necessarily apply to Sonapahar (The Business Standard, 2026). Hence, long term monitoring will be crucial to assess if the forest brings about measurable biodiversity, soil, carbon storage and local environmental resilience. This is especially relevant from an NbS perspective, as in IUCN Global NbS there are eight criteria for assessing the quality and sustainability of NbS. These indicators are not only environmental but social, economic, governance, trade-offs and long-term sustainability issues are also taken into account (IUCN, 2020). Evidence and Impacts of the NbS Field research and monitoring data from Project Sonapahar demonstrate improvements compared to afforestation. Environmental Impacts and Ecosystem restoration: The main purpose of Project Sonapahar was to fix land degradation caused by hill cutting, topsoil erosion and toxic emissions from local brick kiln operations in Jorargonj union of Mirsharai. From this figure the project changed land into a multi-layered native forest within 13 months. Biodiversity net gain: Establish a high-density botanical forest of 120 trees, shrubs and climber species. The project grows natural forest layers of canopy, sub-canopy, and shrub in Chattogram. This species diversity provides urban habitat and shelter for birds, pollinators and creatures in soil (Prothom Alo, 2023; Rahman, 2023). Soil microbial activation: Using decomposed plant material to prepare the soil as shown in the stage 2 helped to restore organic soil structure, enhancing moisture and reactivating microbial activity.

58Carbon absorption: Utilizing Miyawaki method enables vegetation growth up to ten times faster and results in a plantation thirty times denser than traditional monoculture forestry. This absorbs carbon storage and biomass accumulation per unit area (Miyawaki, 1999; Schirone et al., 2011). Disaster Risk Reduction (DRR) and climate resilience: This place is frequently exposed to heavy rainfall, flash floods and cyclones. Project Sonapahar directly contributes to localized disaster risk reduction and fight against climate dangers (Smith et al., 2021) Soil stabilization and slope protection: The thick roots from the native trees hold the soil together. This prevents the soil from washing, sliding down hills and flowing away during heavy rainfalls. Microclimate Regulation: The multi-layer canopy reduces localized heat island effects by filtering solar radiation, lowering ambient surface temperatures and increasing relative humidity. Hydrological Regulation: Soil loosening and organic matter enhance surface soil permeability. Adding more plant matter helps rainwater get into the ground faster. This helps refill water and stop water from building up on the surface. Social and Community Impacts: Although Project Sonapahar operates within a private footprint, it helps the public by spreading awareness, teaching people and pushing for better impacts (Tasnim et al., 2021). Demonstration Model for Replicable NbS: The site functions as a practical proof-of-concept for regional landowners, academic institutions, community members and it proves that even small areas can be restored quickly (Rahman, 2025; The Business Standard, 2025). Environmental Health Improvement: Replacing industrial brick-kiln to spaces improves the air by filtering dust. This makes life better and looks nicer for nearby people. Long-Term Cost-Efficiency: The Miyawaki technique involves higher initial capital costs for intensive soil preparation, its rapid canopy maintenance, weeding and irrigation costs after 2 to 3 years, making it economically sustainable over time (Miyawaki, 1999; Seddon et al., 2020). Preservation of Ecosystem Service Value: Re-establishing natural ecological processes safeguards baseline land asset value without needing expensive grey engineering infrastructures. Accelerated Growth Metrics: Tracking shows that after 13 months some trees grew more than 17 feet as seen in the figure for stage 3. This is much faster than tree plantation. IUCN NbS Self-Assessment: Project Sonapahar The IUCN Global Standard for Nature-based Solutions Self-Assessment Tool was applied to evaluate Project Sonapahar (a 4,400 square feet) Miyawaki micro-forest built on degraded brick-kiln land in Mirsharai, Chattogram) across all 8 Criteria and 28 Indicators. Transition to Self-Sustainability: By approximately month 36 the forest has a roof of leaves. It takes care of itself without help from people and also satisfies key performance benchmarks for high-functioning NbS standards (IUCN, 2020).

59Criterion 1: Societal Challenges (Rating: STRONG) Satisfies Indicators 1.1–1.3 by directly targeting the degradation of topsoil due to past brick-kiln activities and reducing ambient dust and industrial heat islands at the local level in Mirsharai (Rahman, 2023). Criterion 2: Design at Scale (Rating: PARTIAL) Evaluated under Indicators 2.1–2.3. Planting density is high (3 saplings per meter square) and as such this does not have a regional watershed hydrology effect (Smith et al., 2021), only the hyper-local microclimate regulating impact. Criterion 3: Biodiversity Net Gain (Rating: STRONG) Fulfills Indicators 3.1 - 3.4 by introducing more than 120 indigenous species of plants in 4 layers of canopy (Emergent, Canopy, Sub-Canopy, Understory) which resulted in the restoration of native microorganisms and pollinators (Miyawaki, 1999; Rahman, 2023). Criterion 4: Economic Viability (Rating: STRONG) Satisfies Indicators 4.1–4.3. Canopy closure occurs quickly with an initial expense of 1.0 m soil excavation, which is then followed by no irrigation, weeding or maintenance costs after Year 3 (Schirone et al., 2011). Criterion 5: Inclusive Governance (Rating: PARTIAL) Evaluated under Indicators 5.1–5.4. It is a self-managed programme so there is central decision-making. It does not have formal municipal co-governance, public participation mechanisms or formal grievance mechanisms. Criterion 6: Synergies and Trade-offs (Rating: ADEQUATE) Meets Indicators 6.1–6.3 by providing a balance between microclimate cooling and eco-tourism education, without ecological trade-offs. But the documentation of formal social safeguards is not written. Criterion 7: Adaptive Management (Rating: PARTIAL) Evaluated under Indicators 7.1–7.3. Field management is flexible, but the site does not have a sensor telemetry system for the continuous monitoring of soil moisture, temperature and micro-climate data. Criterion 8: Mainstreaming and Sustainability (Rating: STRONG) Satisfies the following Indicators: 8.1–8.3 (Dwijen Sharma Poribesh Padak 2024 – A national proof-of- concept for industrial policy replication – The Business Standard, 2024). High Performing Areas Biodiversity Net Gain (Criterion 3), Economic Viability (Criterion 4), and Mainstreaming (Criterion 8). It is designed ecologically, in such a way that it is self-sustaining and has no long-term maintenance costs (Miyawaki, 1999; Schirone et al., 2011). Indicators with Limited and Unavailable Evidence Indicator 2.2 (Landscape Connectivity): Lack of spatial information about the connection between forest and regional landscape ecological corridors. Indicator 5.2 (Governance Inclusivity): Absence of formal civic co-management agreements in private property ownership scenario. Indicator 7.2 (Monitoring Telemetry): Lack of automatic micro-climatic or soil monitoring sensors.

60Overall Quality and Sustainability Synthesis Overall, Project Sonapahar achieved an assessment score of 78.4 percent, which falls within the adequate category. The IUCN assessment shows that Project Sonapahar is a good quality micro-scale NbS. Ecological sustainability is ensured by the selection of the native biodiversity, while financial sustainability is ensured because it does not require any maintenance costs in the long term (Miyawaki, 1999; Schirone et al., 2011). Expansion of the project to a macro-scale landscape solution should involve public co-governance structures (Criterion 5) and include interconnections of green corridors (Criterion 2). Strengths, Limitations and Challenges By utilizing the Miyawaki method, Project Sonapahar accelerates natural forest growth, creating a dense, multi-layered canopy in two to three years compared with 20–30 years under conventional afforestation (Miyawaki, 1999). The site adds more than 120 native plant species within a small area of 4,400 square feet, restoring vertical ecological niches for local birds, pollinators, and soil microbes (Rahman, 2023). Although initial soil preparation and organic conditioning are costly, after three years the project requires zero irrigation, fertilizer, or weeding, making its lifecycle highly cost-effective and financially autonomous (Schirone et al., 2011). It also offers a successful proof-of-concept for converting severely degraded, damaged topsoil removed from brick-kiln sites into ecological micro-reserves. The site functions mainly as a hyper-local cooling island and dust buffer but cannot alter the local water flow of the watershed or the disaster risk of the region (Smith et al., 2021). In addition, no weather stations or soil sensors are currently in place to continuously monitor temperature changes, carbon uptake, and soil moisture replenishment over time, leaving a gap in continuous long-term empirical data. Intensive initial site preparation deep digging to 1.0 m and heavy organic soils requires considerable labor, technical expertise, and financial investment, while high-quality saplings of over 120 species are difficult to source, since local nurseries generally favor commercial monoculture species such as Acacia or Eucalyptus. The micro-forest is also at risk of edge effects and heat radiation from surrounding industrial factories, as well as potential pest outbreaks if species diversity is not carefully monitored. Located in the industrial corridor of Mirsharai, the site faces long-term commercial pressure from land value speculation and may not be preserved permanently without formal legal status. Because the project is privately funded, public access and decision-making depend on private management policies, raising issues for equitable long-term management, and local communities were not formally co-designers, limiting their sense of civic ownership and role as decision-makers. The project also involves trade-offs between environmental, social, and economic objectives: high per-square-foot investment prices favor intensive ecological restoration over planting more widely at lower density and cost, while the commitment to conserving commercially valuable land represents an opportunity cost in terms of short-term economic development or commercial land use. Conclusion Project Sonapahar shows the Miyawaki method can restore degraded brick-kiln land, creating a dense native ecosystem of 120+ species in 4,400 sq ft (Rahman, 2023) and scoring strongly under the IUCN NbS framework for community problem-solving, biodiversity gains, and ecosystem potential. It is highly effective at the micro-scale—fixing topsoil, cooling locally, filtering dust, and restoring pollinators but limited against macro-scale risks like flooding due to its small size. Strengths: rapid canopy growth, self-sufficiency after three years, zero long-term maintenance, high biodiversity density, and brownfield reclamation. Limitations: micro-spatial scale, private control without formal community co-management, and no real-time sensors (Smith et al., 2021). The model is replicable for industrial pocket forests across Bangladesh, and linking them into green corridors with formal public-private-community governance would maximize regional climate resilience.

61References Ahmed, B., Rahman, M. S., Islam, R., & Sammonds, P. (2021). Perceived human-induced causes of landslide in Chattogram Metropolitan Area in Bangladesh. International Journal of Disaster Risk Reduction, 56, Article 102123. https://doi.org/10.1016/j.ijdrr.2021.102123 Alam, M. S. (2017). Environmental degradation through hill cutting in Chittagong district of Bangladesh. Journal of Environmental Science and Natural Resources, 10(2), 143–152. https://doi.org/10.3329/jesnr.v10i2.35952 BRAC Bank. (2024, October 10). BRAC Bank and Tarupallab honour environmental heroes with Dwijen Sharma Poribesh Padak 2024. The Business Standard. https://www.tbsnews.net/economy/corporates/brac-bank-honours-champions- poribesh-padak-1224626 Hassan, M. M., Mahmud, M. A., & Islam, M. S. (2015). Land degradation and environmental impacts of hill cutting in Chittagong. Journal of Geography and Regional Planning, 8(8), 205–214. https://doi.org/10.5897/JGRP2015.0501 International Union for Conservation of Nature. (2020). IUCN Global Standard for Nature-based Solutions: First edition. IUCN. https://portals.iucn.org/library/node/49070 IUCN Bangladesh. (2025). Evaluating nature-based solutions and ecosystem restoration in coastal Bangladesh. IUCN. https://www.iucn.org/asia/countries/bangladesh Miyawaki, A. (1999). Creative ecology: Restoration of native forests by native trees. Plant Biotechnology, 16(1), 15–25. https://doi.org/10.5511/plantbiotechnology.16.15 Prothom Alo. (2023, November 12). Miyawaki forest in Chattogram: Turning degraded land into a green pocket. Prothom Alo. https://www.prothomalo.com/bangladesh/district/aohg144lyo Prothom Alo. (2024, August 18). Transforming degraded industrial land through dense afforestation in Mirsharai. Prothom Alo. https://www.prothomalo.com/english Rahman, A. (2023, June 5). Bangladesh's first private Miyawaki forest: Project Sonapahar. Inside Bangladesh. https://www.insidebangladesh.com/environment/project-sonapahar Rahman, A. (2025). Replicating pocket forests for urban climate resilience in Chattogram. Urban Forestry & Urban Greening, 92, Article 128100. https://doi.org/10.1016/j.ufug.2025.128100 Schirone, B., Salis, A., & Vessella, F. (2011). Effectiveness of the Miyawaki method in Mediterranean forest restoration. Ecological Engineering, 37(6), 823–829. https://doi.org/10.1016/j.ecoleng.2010.02.004 Seddon, N., Chausson, A., Berry, P., Girardin, C. A. J., Smith, A., & Turner, B. (2020). Understanding the value and limits of Nature-based Solutions to climate change and other global challenges. Philosophical Transactions of the Royal Society B, 375(1794), Article 20190120. https://doi.org/10.1098/rstb.2019.0120 Smith, A., Girardin, C. A. J., & Seddon, N. (2021). Nature-based solutions for disaster risk reduction and coastal climate resilience. Environmental Science & Policy, 124, 120–131. https://doi.org/10.1016/j.envsci.2021.06.011 Tasnim, S., Islam, R., & Rahman, M. S. (2021). Community perception and social impacts of localized greening initiatives in industrial corridors. Land Use Policy, 108, Article 105520. https://doi.org/10.1016/j.landusepol.2021.105520 The Business Standard. (2023, October 15). Experimental Miyawaki micro-forest shows rapid growth in Mirsharai. The Business Standard. https://www.tbsnews.net/bangladesh/environment The Business Standard. (2024, May 20). Evaluating the potential of Miyawaki forests for urban ecosystem restoration. The Business Standard. https://www.tbsnews.net/feature/environment The Business Standard. (2025, February 10). Private green initiatives lead the way in industrial wasteland reclamation. The Business Standard. https://www.tbsnews.net/bangladesh/environment

9 Floating Treatment Wetland Systems for Waterlogging and Ecological Restoration of Dhanmondi Lake as a Nature Based Solution (Nbs) Umme Sayma Jim & Meher Niaz MuhuAbstract Dhanmondi Lake has problems with water pollution and eutrophication. These problems make flooding worse. Reduce the value of the ecosystem. This study looks at the Floating Treatment Wetland System that was set up at the lake. The study uses the IUCN Global Standard for Nature-based Solutions to see how effective and how long-lasting this approach has been. The project worked well in improving water quality and bringing back plants and animals. It used cheap methods with plants. However, it did not do well in areas like making sure everyone in the community was involved in planning money and having management systems. Overall, the Floating Treatment Wetland System worked well scientifically. Also, this project is not expensive. To keep it going for a long time more people need to be involved and there needs to be more money that keeps coming in. Keywords: Eutrophication, Wetland, WaterloggingDepartment of Disaster Management and Environmental Studies, Brac University, BangladeshIntroduction Water scarcity has become a new concern in resource management, prompting researchers to seek sustainable solutions that combine environmentally friendly technologies and a circular economy. Due to the important role of water in environmental, economic and social aspects, it is very important to develop various types of technologies to treat water waste and make water reusable. Waterlogging is a major problem in Dhaka, Bangladesh and also the entire world.Technological development, unplanned urbanization, and economic development have exacerbated such problems. The waterlogging problem affects rural agricultural people as well as city dwellers. In the past, it was mainly farmers who suffered from this damage; but now, houses in big cities are also being severely affected. Waterlogging poses a serious humanitarian crisis, posing challenges to the quality of life, livelihoods, health, food, security, employment, education and communication systems for months. Moreover, unplanned and uncontrolled urbanization processes have turned this waterlogging into a death trap for city dwellers. Urban waterlogging causes traffic jams and wastes working hours. Sanitation problems, diseases and shortage of clean water are very common in waterlogged areas (Rahman, K M & Debnath, Sankar et al., 2015). Dhanmondi Lake, a recreational and environmental resource in central Dhaka, clearly illustrates these challenges. Despite being originally a wetland and part of a river system, Dhanmondi Lake is now suffering from eutrophication (algal blooms due to excess nutrients), untreated wastewater intrusion, solid waste accumulation, invasive aquatic plants, and poor water quality.62

63These conditions directly lead to waterlogging which saturates the soil and surface water when drainage systems can no longer handle it and weakens the lake’s ability to retain stormwater. This problem is important because Dhanmondi Lake serves as a green-blue infrastructure. It serves thousands of visitors, sustains remaining aquatic life, cools local temperatures, and has historically helped manage stormwater. The ongoing damage to the lake increases health risks. Makes it harder for the city to handle climate change. This includes issues like the loss of wetlands and problems with drainage. Bringing back the ecological and water flow functions of lakes such as Dhanmondi Lake is crucial. It helps reduce the risk of disasters and builds climate resilience. Wetlands are essential for all living things, from humans to aquatic organisms, small and large fish, phytoplankton and zooplankton. That is, the entire surface water bodies act as the driving force of the ecosystem. However, due to current human activities, water bodies are being polluted. The natural movement of aquatic ecosystems and aquatic sources are being destroyed due to pollution, many of which are even disappearing and disappearing. In a word, biodiversity is being destroyed and people are also facing a hostile environment. Therefore, to bring the ecosystem back to its normal state, it is very important to purify surface water to preserve biodiversity in a proper manner and ensure the reuse of water for the right means and purposes. The selected Nature-based Solution for this case study is the use of Floating Treatment Wetland Systems also called floating islands or floating constructed wetlands. These systems are being applied at Dhanmondi Lake along with ecological restoration efforts. FTWS consist of platforms that are planted with emergent macrophytes. The roots of these plants hang down into the water helping to clean the water through phytoremediation. They also support biofilm development that removes nutrients and provides habitat for life. Pilot projects using FTWS have already been carried out at Dhanmondi Lake. These projects were conducted as part of research between Bangladeshi and international partners. The work was supported by the Asia-Pacific Network, for Global Change Research under its framework (APN, 2024; The Himalayan Times, 2024). Therefore, this floating purification wetland system is a very effective and innovative project to revitalize the ecosystem of Dhanmondi Lake and the surrounding environment in harmony withnature. This method is both environmentally friendly and cost effective. This plant-based purification method uses plants and floating rafts to purify polluted water bodies the plant-based purification method helps to purify water bodies and restore them to their original state. (Kayastha,S.P et al., 2024) The goal of this task is to talk about and look closely at the steps needed to fix the Dhanmondi Lake floating treatment wetland. It also looks at the projects that help the environment. By discussing Dhanmondi Lake floating treatment wetland and the projects that help the environment we can see how to protect our environment. It looks at the problems of water quality, many nutrients and dangers to the environment that happen in cities. It uses the IUCN Global Standard for Nature-Based Solutions as a self-assessment tool to assess the effectiveness, evidence of impact, strengths, limitations and overall sustainability of this nature- based solution. The analysis relies on peer-reviewed literature, project reports, government and media documents and available monitoring data to assess its effectiveness and scalability by reviewing local NBS. Background and Context One of Bangladesh's most densely urbanized area Dhanmondi is located in the central part of Dhaka, approximately at 23°43′N, 90°26′E. Dhanmondi lake was originally a neglected channel of the “Karwan Bazar Nadi” which was possibly aligned with Begunbari Khal-Green Road Kalabagan-Dhanmondi Lake to the Turag river.

64A portion of the lake remains connected to the storm water drainage system discharging water into Begunbari khal. 16% of the Dhanmondi area is surrounded by the lake. The lake is 3 km long, 35-100m breadth with maximum depth of 4.77m and the total area of the water body is 37.37 ha. Several renovation works were conducted around Dhanmondi Lake from 1998 to 2001 to make it pollution free. (Dhanmondi Lake - Banglapedia, n.d.-c) Because of infilling and urbanization 60-75% of the lake was reduced from 1972 to 2020. (Nabila et al. 28) According to the article Fresh Water Biology, the lake is heavily contaminated sewage, industrial effluents, and municipal and domestic waste water with phosphate levels in the hypereutrophic range 0.34 to 0.85 ppm. (Ollard et al., 2023b) Another 13 months of study on the lake shows that parameters including dissolved oxygen, biochemical oxygen demand, nutrients, conductivity, turbidity, and pH has been a significant environmental concern. (Ali et al., 2022b) A significant share of Dhaka's yearly rainfall occurs during the monsoon period from May to September. This year waterlogging was seen surrounding Dhanmondi Lake by continuous rainfall, disrupting pedestrian movement. ("Dhaka built over floodplains," 2026) Also the microplastics were found relatively higher in fish samples that were used from Dhanmondi Lake. Which contributes to increasing the pressure on the drainage system. (Mercy et al., 2023) Dhanmondi Lake's CTSI ranged from 69.3 to 79.5 demonstrating initial "Eutrophic" conditions progressing to "Hypereutrophic." Eutrophication refers to when too much nutrition enters the lake it can cause abundant algae growth. ((Faria et al., 2024) A 2025 study also shows significant microplastics pollution in Dhanmondi lake along with the linked pollution pressure to declining biodiversity. (Chowdhury et al., 2025b) Plastic pollution is another potential threat to the aquatic organism and ecosystem. According to the description above, if we inspect the waterlogging problem first, the communities who would be affected first are local residents, pedestrians and commuters and students and educational communities as flooding and drainage system problems can affect everyday mobility or disrupt transportation accessibility. These are considered great issues as a study survey shows that 400 visitors have claimed Dhanmondi Lake as an important aspect of their experience. (Journal of Event, Tourism and Hospitality Studies, n.d.). Also, people can be affected by change of water as the residents who live near Dhanmondi Lake mostly depend on the lake environment and eco system services. Dhanmondi Lake is also a provider of fish, birds, aquatic organisms, and plants. 6 fish, 18 birds, and 34 plant species in and around the lake in a document. (Daffodil International University, n.d.) In terms of the affected sector the most affected will be the transportation system. Then comes education as the educational institutions can face accessibility problems during heavy rainfall and waterlogging. Local businesses can also be affected due to waterlogging. The recreational value of the lake can be reduced because of the poor water quality and degraded surrounding as Dhaka is mostly surrounded by grey infrastructure, the lake creates attractions to the tourists all over the city. Dhanmondi Lake is also connected to storm water drainage management changes in the lake’s physical and ecological characteristics affects the urban area management (IUCN Bangladesh & Global Center on Adaptation, 2025) Description of The Nature-Based Solution The Floating Treatment Wetland System is basically a text green technology which is used to decontaminate water bodies. (Byanju et al., 2024) In other words, it is a simple technology which can be installed and operated at very low cost using locally sourced waste materials. If local stakeholders and stakeholders are initially educated and trained about this technology, they will be able to learn it very easily and they will be able to use that knowledge at the field level. Since the cost of this technology is very affordable, it is a practical solution to keep water bodies free from pollution, especially in developing countries.

65Some of the advantages of this technology are that due to its floating ability, it does not hinder the water body's holding capacity and uses the energy of sunlight for water body purification. In addition, its maintenance and operation cost is minimal as the local plants from which it is made are very easily available. (Shahid et al., 2018) In fact, FTWS is an innovative and emerging technique and method which plays an important role in water body pollution treatment. (Zhang et al., 2014) It uses a large amount of floating mats, which define the deepest rooted plants and the roots hang freely down to the bottom of the water. Another great advantage is that these roots in the water create a microbial biofilm, which then acts as a remediation process. (Afzal et al., 2019) Floating Treatment Wetland Systems (FTWS) consist of a freely floating artificial buoyant raft that supports phytoremediation plants and allows their roots to hang freely in the water column (Afzal et al., 2019). These floating roots directly absorb nutrients from the water to accelerate the absorption of nutrients and elements into the plant biomass (Tanner & Headley, 2011). In addition, pollutant- disrupting microorganisms associated with the roots also absorb nutrients and remove solids, heavy metals, or various impurities from the water (Ijaz et al., 2016). These microorganisms trap gases on the surface of the roots to increase the buoyancy of the raft (Afzal et al., 2019). This buoyancy helps the rafts in several ways. For example, it helps them to withstand large fluctuations in water depth. It also helps control the position of rafts to improve the water quality of the reservoir (Tanner & Headley, 2011) The FTWS pilot projects were set up directly in Dhanmondi Lake in Dhaka. The initiative was launched to test a low-cost, low-energy, eco-technological approach to reducing nutrient and organic pollution in urban surface waters where conventional wastewater treatment infrastructure is inadequate. The FTWS responds to the documented eutrophic/hypereutrophic condition of the lake and broader need for a scalable solution which is applicable to other degraded urban bodies of water in South Asia. (APN, 2024). Various factors have been considered while designing a FTWS. Appropriate planning and a conceptual framework for site selection, microenvironmental studies, plant selection, field prototype implementation, and laboratory testing have also been prepared. The exact scale of the floating rafts and surface structures is carefully calculated during the preparation phase. The COVID-19 changes in household wastewater, bleaching powder use and overground chemical application have reduced the capacity of urban lakebeds (Kayastha, 2024) or (APN, 2024). Poor wastewater treatment infrastructure has resulted in nutrient levels in leachate leading to eutrophication (Bhat et al, 2022). This nature-based solution (NBS) technology has already been tested (Small Earth Nepal, 2024). The COVID-19 pandemic has worsened overload in surface water bodies. These water bodies are receiving levels of pharmaceuticals, disinfectants and their byproducts in wastewater. The presence of emerging pollutants in wastewater environments creates a big challenge for developing countries. These countries lack wastewater management infrastructure. As a result, wastewater is often released directly into water bodies. This practice poses risks to aquatic environments and human health. To address the need for wastewater treatment systems in the COVID-19 era our proposed research project emphasizes an integrated microcosm and field approach. This approach will test the ability of Floating Treatment Wetland Systems (FTWS) to remove water pollutants. The system uses native plant species and floating rafts made of waste materials. The microcosm portion will serve as a thesis for postgraduate students. Selected water quality parameters will be analyzed to determine the impact of FTWS on reducing concentrations. Along with the plant species that have been proven to be most effective in removing contaminants. The main people who benefit are residents who get better looks and places to relax, fewer mosquitoes and bad smells and better feelings and health because of a cleaner lake. People who live near the lake also get mental and physical health from a healthier environment.

66Others who benefit include fish, small creatures in the water and birds. Also, city workers who want ways to manage things, scientists who are learning more about natural ways to solve problems and communities that might work in growing plants or taking care of them. Some of the benefits are better water quality FTWS helps take out much food for plants, heavy metals and other bad things in the water by using plants and tiny living things. This will make the water cleaner and help bring back the lake and pond life. It helps keep nature and water life safe FTWS makes the water better for animals and plants to live in. FTWS gives a place for water animals and birds that travel to live which helps kinds of living things grow. It looks nice and its ability to change design FTWS can have styles that make the water look better and add value to the whole place. The way it can be designed and the nice looks help make the place more fun for visitors and people who want to spend time. How well it works depends on how bad the water's, how fast the water moves and how warm it is. Different places have problems and different kinds of water which can change how well the system works. (Department of Environment, Science and Innovation 2022). The ecosystem involved is the lacustrine system ivolved. It consists of a floating platform with plant assemblages. It also includes coastlines and adjacent habitats. This system is an urban aquatic ecosystem. It is known as the Urban Freshwater Wetland Ecosystem (APN, 2024). This nature-based solution has led to the restoration of lost microflora. It has also brought back life and restored ecological balance (Bhatt et al., 2022). At the time it has created a new artificial habitat. This artificial habitat is a micro-habitat, for birds and other amphibians (The Small Earth Nepal, 2024). Adressing the Issue Dhanmondi Lake has a problem with eutrophication or hyper eutrophication caused by many nutrients. And this problem got worse during the COVID-19 period because of more household wastewater, more use of bleaching powder and more chemicals washing into the water. Since these countries do not have wastewater treatment systems the pollutants like nutrients, heavy metals, medicines and cleaning agents go straight into the lake. This is bad for the fish and other creatures in the water and for people who live nearby. Floating Treatment Wetlands (FTWS) address nutrient pollution and eutrophication through direct nutrient uptake, as plants on the floating rafts have roots suspended in the water that absorb nitrogen and phosphorus and convert them into plant material. The roots also host a layer of microorganisms that break down and remove heavy metals, dirt, and other pollutants, adding to the plants' uptake. The system is self- sustaining and low-tech, using easily found materials and sunlight to clean water without electricity or expensive equipment—exactly what is needed where wastewater treatment systems are absent. Air trapped by the roots and microbes improves buoyancy, allowing the system to keep working as water levels and lake conditions change, and because it is inexpensive and adaptable, it is a good solution for other degraded lakes lacking proper wastewater treatment in South Asia. The real problem is excess nutrients and pollution from untreated water, and FTWS solves this by using plant roots and their surrounding microorganisms as an inexpensive way to clean the water. Evidence and Impacts The FTWS pilot at Dhanmondi Lake has brought results in many areas even though the lake is still on the path to full recovery. These results include water quality, stronger communities, more economic opportunities and improved ability to handle climate challenges. The sections that follow go into each of these benefits one, by one. Results from the project have shown that the system is capable of pollutant removal․ Studies conducted by APN in laboratory and field conditions show that the system is capable of removing pollutants․ Small-scale experiments conducted with species such as Canna indica and Tradescantia pallida have shown drops in ammonia and BOD․ The system increased dissolved oxygen and considerably reduced nitrate (APN‚ 2024)․

67Freshwater mussels are also good for cleaning the water, by filtering out particles. This shows how well they can filter water (Bangladesh Post, 2023). At the time what people see in the field shows that some plants can live in open water and take in nutrients. However, there is no public data over a long time to show that the Dhanmondi FTWS has improved the lake. Studies of the lake's health still say it is between eutrophic and hypereutrophic. This means that nutrients coming from outside are still more than what's being cleaned up (Islam et al. 2024). Putting floating plants in the lake has increased the oxygen levels by up to 53 percent. This helps the fish that live there and gets rid of the smell the lake usually has. The hanging roots of plants such as kelp, vetiver grass and water hyacinth help stop algae from growing. This has led to a fall in the amount of phosphorus and nitrogen in the lake (Kayastha et al., 2024). These roots act as filters. They catch pieces of trash and clean the water around them. Improvement in water quality and reduction of floating aquatic vegetation can play an important role in social change, such as enhancing the recreational experience of walkers, joggers and participants in cultural events in Rabindra Sarovar and its surrounding areas. It has also played a role in public health, such as ensuring clean water and suppressing mosquito breeding.Increasing public awareness activities will further increase local awareness about stewardship. The role of the lake as an accessible public space supports social cohesion and mental well-being in densely populated urban environments, which is consistent with Sustainable Development Goal 11.7 on inclusive public spaces. FTWS are comparatively less expensive than traditional wastewater treatment infrastructure. Some of its positive economic impacts are: Conventional wastewater treatment systems required capital investment and land acquisition of crores of taka. For example, central mechanical filtration projects. On the other hand, the Dhanmondi Lake FTWS has been constructed using affordable, readily available and recyclable materials like bamboo, PVC pipes, coconut husks and indigenous aquatic plants like vetiver grass and kelp. This innovative system floats on the water surface, which has become a major advantage for the prime and high-value real estate area of Dhanmondi. As it does not require costly land acquisition or infrastructure footprint. Unlike other mechanical water aerators or purification plants, the FTWS relies entirely on solar energy and the functioning of natural ecosystems (biological absorption through plant roots). The project has eliminated the need for repeated purchases of expensive chemical treatments such as algaecides or copper sulphate, which are commonly used to control toxic green algae outbreaks but ultimately cause long-term environmental damage. The project has played a significant role in reducing odors and nuisances caused by decomposing organic matter. For example, dissolved oxygen levels have increased by fifty-three percent. DSCC has announced a large-scale recovery investment, which includes a renovation package of Tk 750 crore focusing on infrastructure, sanitation, and cultural infrastructure (TBS News, 2026a). By improving the ecological functions of the lake, NbS helps retain residual storage capacity in the lake and therefore its function as an element of the urban drainage system. Improving the lake’s vegetation and shorelines will reduce the problems of erosion and sedimentation. In addition, with rising temperatures and heavier rainfall, a lake is a good way to locally reduce temperatures and offer protection from extreme weather. These are additional indirect benefits of restoring the natural functions of urban lakes that go beyond the main NbS interventions (improving the drainage system) and complement the extensive hard engineering interventions mentioned by the authorities. Note that these benefits further relate NbS to disaster risk reduction and climate change adaptation (TBS News, 2026b). IUCN NbS Self-Assessment Societal challenges - 14/18 (78% Adequate): the FTWS project clearly identified the water pollution and health risks that Dhanmondi Lake residents face thereby meeting the social need it was created for. Still societal challenges remain, with waste illegal food carts and misconceptions about mosquito breeding that must be tackled.

Integrated Systems Perspective - 15/18 (83% Strong): We notice that the project linked restoration with Dhaka's social and cultural life, such as Rabindra Sarovar Adda and lakeside food culture that had been disrupted by pollution and odor. Yet Integrated systems perspective still faces a gap as plastic waste from food vendors continues to create a link between the social and ecological systems. Enhanced Biodiversity, Ecosystem Integrity - 18/21 (86% Strong): the project used a framework with measurable science‑based outcomes showing real restoration of biofilm and root‑based ecological function. Enhanced biodiversity ecosystem integrity is proven, as small‑scale NbS can truly restore biodiversity in an urban lake. Financial Feasibility & Economic Justification - 5/15 (33%, Insufficient): Initial costs were low and carefully calculated using materials such as PVC pipes and coconut husks with odor reduction adding value. Yet Financial feasibility & economic justification suffered due to a lack of benefit sharing and no long‑term financial sustainability plan. Inclusive Governance & Equity - 5/27 (19%, Insufficient): Stakeholders were identified. Marginalized communities and the general public were left out of design and feedback processes leading to a top‑down approach. Inclusive governance & equity was weakened by communication that caused public misunderstandings, such as fears about mosquito breeding, which could have been avoided with participatory mechanisms. Balancing Goals & Impacts - 5/15 (33%, Insufficient): Balancing goals & impacts was limited with the project a scientific research effort by Dhaka University and APN. No corrective action plan was developed for concerns raised by locals and there was no transparent or participatory process to manage trade‑offs between stakeholders. Adaptive Management - 10/18 (56%, Partial) : Adaptive management focused on technical water‑quality metrics leaving out socio‑economic factors such as community dissatisfaction. Adaptive management also lacked a complaint system or long‑term corrective mechanism to adjust the project based on public feedback. Enhancing Sustainability & Mainstreaming - 9/15 (60%, Adequate): Enhancing sustainability & mainstreaming produced scientific knowledge that aligns with SDGs 6, 11 15 and Bangladesh's Delta Plan and it now serves as a model for DSCCs restoration efforts. Yet Enhancing sustainability & mainstreaming did not share its findings with the public limiting broader social awareness and behavior change. Overall View of Self-Assessment The Dhanmondi Lake FTWS initiative scored 81 out of 147 points which's 55 percent. That means it does not fully meet the IUCN Global Standard for Nature‑based Solutions. The project did well in the ecological and technical areas. It scored 83 percent in the integrated systems category and 86 percent in biodiversity. These high scores show that the science behind the project is solid and that the environment is improving. The project did not do as well in social and institutional areas. Governance and equity received 19 percent financial feasibility 33 percent and balanced trade‑offs 33 percent. This poor performance is mainly because the project was managed from the top down and did not involve communities. Overall, the Dhanmondi Lake FTWS initiative has a scientific base. It still needs community involvement, stronger financial planning and clearer governance to become fully sustainable.68

69Strengths & Limitations Aligning directly with IUCN's core NbS goal of natural water purification, Dhanmondi Lake’s severe water pollution and nutrient overload as a genuine social and environmental threat were accurately identified by the FTWS project. The lake receives pollution from surrounding urban activities and drainage, which contributes to poor water quality and creates pressure on its aquatic ecosystem. The project uses natural processes and plants to absorb excess nutrients, improve water quality, and support ecological restoration. The project demonstrated genuine ecological–social integration by improving both the environmental condition and social and cultural space such as Rabindra Sarovar adda, food culture and community gatherings. This shows that the NbS approach not only treats environmental problems in isolation but also works across interconnected systems. The FTWS project was built on a rigorous scientific baseline to ensure that the proposed solution was supported by reliable environmental data and not an assumption. Researchers from the University of Dhaka measured dissolved oxygen (DO), biochemical oxygen demand (BOD), nitrate, phosphate, and heavy metals to understand the depth of the pollution which provided clear evidence of nutrient enrichment, organic pollution, and other water-quality concerns. This creates a strong and defensible technical foundation for planning, monitoring, and demonstrating the success of the NbS intervention. The FTWS project relied on precise budgeting on low-cost local materials. Compared with conventional grey infrastructure Floating Treatment Wetlands require less construction, land, and financial investment as Dhanmondi Lake creates significant limitations on available space. The approach is both affordable and space-efficient, making it well suited to the densely populated urban environment of Dhanmondi. The FTWS project is directly connected to the Sustainable Development Goals, particularly SDG6 on clean water and sanitation, SDG 11 on sustainable cities, and SDG 15 on protecting terrestrial ecosystems and biodiversity. It also supports the objectives of Bangladesh’s Delta Plan 2100 and National Adaptation Plan by promoting sustainable water management, ecosystem restoration, and climate-resilient urban development. The project can serve as a proof of concept for larger nature-based restoration and drainage initiatives by the Dhaka South City Corporation. The FTWS project has continuous limitations and challenges. Illegal food carts and improper plastic waste around Dhanmondi Lake can interfere with the floating treatment system and reduce the quality of the surrounding environment. These never-ending human activities make long-term water-quality management more difficult. Effective waste management and regular monitoring are necessary to ensure the project is maintained. Another challenge the project faced is related to public misinformation and limited community awareness. Without clarifying the purpose and benefits of the floating wetlands, some residents misunderstood that the floating plants could become breeding grounds for mosquitoes. These concerns make it more difficult to gain community support and ensure proper care of the wetlands. Regular awareness campaigns, clear explanations, and community involvement are needed to build public trust and encourage people to support the project. The FTWS project had a limitation in the availability of local and social baseline data. Aside from the fact that detailed scientific measurements provided a strong understanding of the lake’s water quality, the limitations stand exactly on how local communities took the lake’s problems. Incorporating regular social surveys and community observations would strengthen the project by combining scientific evidence with the experiences and knowledge of local residents.

70The FTWS project also faced challenges related to distributive equity and stakeholder participation. There was no clear framework for ensuring that the benefits of the project were shared fairly among different community groups. The responsibilities and costs of maintaining the system were not clearly distributed among stakeholders. identifying beneficiaries and cost bearing stakeholders more clearly, along with developing an equitable benefit-sharing approach, would make the project more inclusive and socially fair. The project also had a limited approach to adaptive management. its monitoring and evaluation (M&E) mainly focused on technical and scientific indicators. While these measurements are important, they do not provide a complete picture of the project’s overall impact. Consequently, emerging social concerns could go unnoticed and remain unaddressed. A broader M&E system that combines scientific, social, and economic indicators would allow the project to respond more effectively. The FTWS project also had a significant policy gap. Despite strong scientific evidence, the results were not clearly incorporated into the policies or restoration plans of key agencies such as RAJUK and the Department of Environment. This limited the project’s ability to influence large-scale urban water management and nature-based restoration. In addition, the lack of policy-supported public awareness campaigns meant that scientific findings did not lead to sufficient changes in community behavior. Conclusion The FTWS project at Dhanmondi Lake shows that using plant-based methods that are affordable can greatly reduce water pollution and help bring back different kinds of living creatures in cities. Clear results like oxygen levels and lower nutrients prove that even small Nature-based Solutions can make real changes in the environment. However, the project rated itself with an IUCN score of 55 percent which shows there are problems with how much the community is involved, how the project is run and how it plans for the future. When the project did not work well with people there was confusion and not much trust from the public. In the future the project needs help from the community, better ways to talk to people and steady money to last a long time. If these parts are made better the FTWS way could be used again in polluted city lakes in South Asia. References Ali, M. A., Ahsanuzzaman, A. N. M., Badruzzaman, A. B. M., Rahman., M. M. (1998), “Lead Pollution of Dhanmondi Lake in Dhaka”, AQUA, 47(5), 289-296. Ali, M. K., Jubaer, A., Zafar, M. T., & Talukder, M. Z. I. (2022b). Physicochemical assessment of Dhanmondi lake water in Dhaka city, Bangladesh. European Journal of Chemistry, 13(4), 402–406. https://doi.org/10.5155/eurjchem.13.4.402- 406.2304] An innovative Floating Treatment Wetland System (FTWS) using the microcosm study to remediate polluted waterbody: A case study of Nagdaha lake. (n.d.). The Small Earth Nepal.https://smallearth.org.np/project/apn-ftws/ Badruzzaman, A.B.M., Ahmad, H. and Ali, M.A. (1999), A Comparative Study of Copper Contamination in the Sediment Column of the Dhanmondi and Ramna Lakes, Res., 18(4), 347-351. Byanju, A., Basnet, C., Pradhananga, D., Pradhanang, S. M., Joshi, A., Pradhanang, S., et al. (2022). Microcosm Study of Floating Treatment Wetlands System (FTWS) to Remediate Polluted Water of Kathmandu Valley, Nepal. AGU Fall Meeting Abstracts, 2022, H22A-06. Byanju, A., Pradhanang, S.M., & Pradhananga, D. (2024). Guidebook: Floating Treatment Wetland System (FTWS). The Small Earth Nepal. Chowdhury, G. W., Aldridge, D. C., & Ollard, I. (2025a). High macroplastic pollution in a subtropical urban lake affects macroinvertebrate community structure. Hydrobiologia, 853(17– 18), 4813–4824. https://doi.org/10.1007/s10750- 025-06035-5 Daffodil International University. (n.d.). A summary of recent studies published by DIU researchers: SDG 15 (Life on Land). Sustainability4D. https://sustainability4d.daffodilvarsity.edu.bd/public/storage/sdg_reports/kViJPCPOXRZ4 dsFkr5pplNHsqBp01Jn9A849dNHNC.pdf Dhaka built over floodplains, lost 15,000 hectares of wetlands. (2026, July 25). Dhaka Tribune.https://www.dhakatribune.com/bangladesh/dhaka/415953/dhaka-built-over-floodplains-lost-15- 000-hectares Dhanmondi Lake - Banglapedia. (n.d.-c). https://en.banglapedia.org/index.php?title=Dhanmondi_Lake

71Faria, F. F., Ariyan, T. N., & Mia, M. Y. (2024). Trophic status analysis and nutrient source allocation in urban lakes of Dhaka, Bangladesh: a comprehensive approach to eutrophication monitoring. Environmental Monitoring and Assessment, 196(12), 1252. https://doi.org/10.1007/s10661-024-13419-y Floating Treatment Wetland System (FTWS) – Sustainable green technology to remediate polluted surface water bodies in the COVID-19 era. (n.d.). Asia-Pacific Network for Global Change Research. https://www.apn-gcr.org/project/floating- treatment-wetland-system-ftws-sustainable-green technology-to-remediate-polluted-surface-water-bodies-in-the- covid-19-era/ Hasan, M. (2026c, August 24). Tk75cr makeover planned to bring Dhanmondi Lake back to life. TheBusiness Standard. https://www.tbsnews.net/bangladesh/infrastructure/tk75cr-makeover-planned bring-dhanmondi-lake-back-life- 1523076 IUCN Bangladesh, & Global Center on Adaptation. (2025). Compendium on nature based solutions for urban resilience in Bangladesh. gca.org Journal of Event, Tourism and Hospitality Studies. (n.d.). https://ejournal.uum.edu.my/index.php/jeth/index Kayastha, S.P., Pradhananga D., Atyal, D., Kumar, R., Pradhanang, S. M., Toyama, T., Rashid T., Bista, N., Khana,l A. (2024). Floating Treatment Wetland System (FTWS) – Sustainable green technology to remediate polluted surface water bodies. Project Final Report. Asia-Pacific Network for Global Change Research (APN). Mercy, F. T., Alam, A. K. M. R., & Akbor, M. A. (2023). Abundance and characteristics of microplastics in major urban lakes of Dhaka, Bangladesh. Heliyon, 9(4), e14587. https://www.sciencedirect.com/science/article/pii/S2405844023017942 Nabila, F. N. ., Mia, M. B., Gazi, M. Y. ., Uddin, M. M. ., Al Montakim , M. N. ., & Alam, M. M. (2023). Assessment of Water Quality and Quantity in the Lakes of Dhaka Metropolitan City - Remote Sensing, Field and Laboratory Analyses. The Dhaka University Journal of Earth and Environmental Sciences, 11(1), 27-42. https://doi.org/10.3329/dujees.v11i1.63709 Ollard, I., Chowdhury, G. W., & Aldridge, D. C. (2023). Functional non‐equivalence in ecosystem engineers? Different freshwater mussels (Bivalvia: Unionidae) are associated with different macroinvertebrate communities in a subtropical lake. Freshwater Biology, 68(10), 1765–1775. https://doi.org/10.1111/fwb.14164] Prothom Alo English Desk, & Prothom Alo English Desk. (2026, July 13). Dhanmondi Lake overflows, Rabindra Sarobar submerged. Prothomalo. https://en.prothomalo.com/bangladesh/p1b8yp4g0p Report, T. (2024b, August 23). Around 1.5 tonnes dead fish found floating in Dhanmondi Lake.

10 A Nature-Based Solution for a Changing Landscape: A Case Study of Bhawal National Park, Gazipur Aleef Al Masud & Dhrubo Agil MreeAbstract Bhawal National Park (BNP) is a crucial Sal Forest ecosystem in Gazipur, Bangladesh, but it faces increasing pressure from urbanization, industrial development, forest loss, and tourism. This case study examines BNP as a Nature-Based Solution (NbS) for addressing ecosystem degradation and biodiversity loss while supporting climate resilience and human well-being. Using published research and the IUCN Global Standard, the study evaluates the park's environmental, social, economic, and disaster risk related benefits. The findings show that BNP supports significant biodiversity, recreation, and ecosystem functions, but challenges such as habitat fragmentation, limited community participation, and weak monitoring remain. The study recommends stronger restoration, community involvement, sustainable tourism, and adaptive management. Keywords: Biodiversity Conservation, Climate Resilience, Ecosystem Restoration.Department of Disaster Management and Environmental Studies, Brac University, BangladeshIntroduction Nature-based solution (NbS) are the actions that protect and manage natural resources sustainably, restore ecosystems, and address social challenges while benefiting people and biodiversity (IUCN, 2022). Bhawal National Park (BNP) in Gazipur is a useful example. Its Sal Forest is a protected ecosystem, a recreational area and a natural resource in a rapid urbanising region. The Park covers about 5022 hectares and is part of the Modhupur Sal. It became a national park in 1982, although protection efforts started in the 1970s (Alam et al., 2026; Alauddin et al., 2020). Bhawal National Park supports wildlife, soil and water regulation, recreation, environmental education, and cultural wellbeing. However, the park is facing threats from land-use charge, infrastructure, industrialization, toursim, and other human activies. The main problem discussed in this case study is the ecosystem degradation and biodiversity loss, while climate resilience and human well-being are considered related benefits. degradation and biodiversity loss as challenges that NbS can address (IUCN, 2020). Recent studies show that forest loss and fragmentation are major concerns in Gazipur and Bhawal National Park. A 2026 Geospatial study found significant Forest cover loss in Bhawal Between 2005 and 2020, mainly linked to human activities, urbanisation, and industrial development (Chakraborty & Talukder, 2026). Another 2026 study found considerable forest loss near the park’s edges with roads increasing the pressure on the forest. (Saimun et al., 2026). These findings indicates that legal protection does not gurantee ecological resilience.72

73Background and Context Bhawal National Park is located in Gazipur District,about 40 km of Dhaka. the park is part of the Rajendrapur Gajari or Sal Forest and lies approximately between 24°01′–24°13′ N and 90°14′–90°30′ E, at an elevatation of about 10-15 m above sea level (Alam et al., 2026). Its landscape consists of gently undulating uplands called Chalas and lower vallyes knowns as Baids. These micro topographic difference affects drainage, vegetation distribution, and the availability of wet and dry habitats. Historically, the wider Gazipur region contained extensive Sal Forest, but urban expansion has transformed much of the surrounding Landscape. The ecological side of Bhawal is very strongly associated with Shorea robusta, which is commonly known as Sal. The Older inventories has documented a diverse flora, which includes trees, shrubs, palms, grasses, climbers and herbs, while fauna include birds, mammals, reptiles and amphibians (Food and Agriculture Organization [FAO], 2000). In More recent field research, which demonstrates that the remaining forest still supports substantial biodiversity. Jaman et al. (2024), for example, recorded 138 bird species and 1,808 individual birds during a year-long survey in BNP, demonstrating that the park remains an important habitat for avifauna. The study also found that deeper forest areas supported more bird species and warned that disturbance associated with recreational use can threaten local bird populations. Forest fragmentation is a growing concern in Bhawal. A 2026 study found that rainfall and population density were major factors influencing the deforenstation risk in Gazipur and which highlights the need for evedance based land zoning and adapting forest management (Chakraborty & Talukder, 2026). Another study reprted the highest forest cover loss near roads and identifies degradation across different part of the park (Saimun et al., 2026). These findings highlight that effective NbS mangement must address not only the forest ecosystem but also the impact of nearby roads, settlements, industries and surrounding land uses. The main environmental challenge is therefore not a single sudden disaster but cumulative ecosystem degradation. Encroachment, illegal or unsustainable resource extraction, unmanaged visitor activity, habitat fragmentation and pressure from nearby development can reduce tree cover, disturb wildlife and weaken ecological connectivity. Earlier research on community management found that indiscriminate use, encroachment, tourism-incompatible activities, illegal felling and grazing were among the major management concerns, while community participation in decision-making was limited (Abdullah et al., 2009). Research on BNP management similarly identified urban proximity, encroachment, private land, industrialisation, fuelwood collection, agriculture and forest fire as important pressures (Alauddin et al., 2020). The social background is very important because protection cannot be isolated from livelihoods and access. The Park is close to a major metropolitan area and attracts visitors for recreation and nature appreciation. Historical management records reported heavy seasonal visitor flows and dependence on park-related resources and livelihoods (Integrated Protected Area Co-management [IPAC], 2010). This creates both opportunities and pressures. Tourism can generate income and public support for conservation, but unmanaged visitor numbers can create litter, noise, trampling, off-trail movement and disturbance to wildlife. As an Institution, the Bangladesh Forest Department has created a Bhawal National Park Management Plan 2015–2025 and an independent Ecotourism Management Plan 2015– 2025, demonstrating that the park is formally managed through planning instruments rather than being an unmanaged forest (Bangladesh Forest Department [BFD], 2025). These plans are important evidence of an institutional framework, although the availability of a plan should not be confused with evidence that every planned measure has been fully implemented or effective.

74Description of the Nature-Based Solution The NbS considered in this case is the protection, sustainable management, restoration and regulated use of Bhawal National Park’s Forest ecosystem. In contrast to a single engineered structure, the intervention is a landscape-scale management system. Its core mechanism is to maintain or improve ecological functions by retaining forest cover, protecting habitat, controlling damaging land uses, restoring degraded areas, managing visitor access and supporting conservation-oriented livelihoods and education. The very first layer of solution is the legal right to protect Bhawal National Parks. So, creating a protected area can create an administrative structure that supervises land use and resource extraction. The Park covers approximately 5,022 ha and includes core and surrounding the management zones (IPAC, 2010; Alam et al., 2026). Protection is intended to conserve biodiversity and ecosystem processes while allowing compatible activities such as controlled recreation and environmental education. A second layer is forest management and rebuilding of forest and its restoration. Because much of the original Sal vegetation has been altered or replaced, management needs to distinguish between conserving remaining semi-natural forest and restoring ecological structure in degraded areas. Recent research on rhizosphere processes in BNP shows why species composition matters. Alam et al. (2026) found significant differences in soil respiration and soil properties among Shorea robusta, Albizia procera and Acacia auriculiformis. The study emphasises that tree identity influences below-ground carbon cycling and therefore supports restoration decisions based on ecological function rather than simply planting any fast-growing species. A third layer is the protection of biodiversity. Forest habitat supports birds and other wildlife, and the presence of 138 bird species in a recent survey demonstrates the conservation value of the park (Jaman et al., 2024). Habitat protection, reduction of disturbance, maintenance of vegetation structure and improved connectivity can therefore provide benefits beyond individual species. The forest also supports ecosystem processes such as litter decomposition, nutrient cycling, soil carbon turnover and microclimate regulation. A fourth layer is the ecotourism in an organized manner. Entertainment is not inherently incompatible with an NbS, but it must be handled so that visitor additional benefit do not ruin the ecological objectives. Designated paths, controlled access to sensitive areas, waste management, visitor education, carrying-capacity assessment and nature interpretation can help align tourism with conservation. The Bangladesh Forest Department's dedicated ecotourism management plan indicates that tourism is recognised as a management issue (BFD, 2025). A lastly the fifth layer is community participation and co-management. Earlier studies of BNP repeatedly identified limited community participation as a weakness. Abdullah et al. (2009) found that local communities were not sufficiently involved in decision-making and argued for collaborative management. From an NbS perspective, this matters because ecosystem management is more durable when affected people can influence decisions, understand restrictions, access legitimate benefits and use grievance mechanisms. So the beneficiaries are therefore very dissimilar: local communities can easily gain livelihood and recreation opportunities; urban and regional visitors gain access to green space; the wider public benefits from biodiversity and ecosystem services; government agencies gain a mechanism for conservation; and wildlife benefits from protected habitat. However, benefits are not automatically equitable. Restrictions on resource access can impose costs on households that historically relied on the forest, which makes participation and trade-off management essential.

75Evidence and Impacts The strongest evidence for BNP's environmental value concerns habitat and biodiversity. The Park remains capable of supporting a diverse bird community. Jaman et al. (2024) recorded 138 bird species from 17 orders and 49 families during their 2020–2021 survey. They found the highest richness and abundance during winter and recorded greater species richness in deeper forest areas. This suggests that forest structure and habitat quality matter, and that maintaining less-disturbed interior habitat is an important conservation action. The Park also served a setting for the below ground ecological processes. Alam et al. (2026) demonstrated species-specific differences in soil respiration, soil organic carbon and nitrogen associated with dominant tree species. This is relevant to NbS because the benefits of a forest are not limited to visible tree cover. Soil processes influence nutrient cycling and carbon dynamics, so restoration and management should consider soil condition as part of ecosystem integrity. Historical ecological inventories also indicate substantial plant diversity. FAO (2000) reported 225 plant species in an earlier inventory, including 42 tree species, 20 shrub species, 5 palms, 27 grasses, 27 climbers and 104 herbs. Such older data should be interpreted as a baseline rather than a current inventory. The absence of a recent comprehensive inventory is itself a management limitation because the IUCN Standard emphasizes evidence-based assessment of ecosystem condition. SThe Park provides recreation, environmental education and opportunities for nature-based livelihoods. Historical research documented local people working as nature guides and in food, transport and other visitor-related services, while also recording dependence on forest resources (Abdullah et al., 2009). This illustrates the potential for conservation and local economic activity to reinforce each other when tourism is managed sustainably. However, the social benefits are accompanied by conflict. Where conservation rules restrict access to land or forest products, households may experience costs. Earlier studies found conflicts related to land rights, resource use and participation. This means that the social success of the NbS should not be measured only by visitor numbers or conservation outputs. It should also be measured by whether affected communities have meaningful roles in decisions, whether benefits reach them, and whether complaints can be resolved fairly. The economic value of BNP includes tourism revenue, employment and avoided costs associated with ecosystem degradation. The Park has historically generated government revenue from entry fees, picnic facilities, accommodation and other visitor services (Abdullah et al., 2009). Local businesses and guides can also benefit from visitor spending. These benefits provide an economic rationale for conservation, although older revenue estimates should not be treated as current values. At the same time, economic feasibility remains difficult to demonstrate because publicly accessible evidence on the full cost- effectiveness of BNP's conservation model is limited. The IUCN Standard requires consideration of direct and indirect benefits and costs, cost-effectiveness, alternative approaches and resourcing options. A robust future assessment should therefore compare the costs of park management and restoration with alternative land uses and with the economic losses associated with continued forest degradation. Disaster risk reduction and climate resilience should not be presented as a substitute for engineered disaster infrastructure. Its disaster-risk contribution is indirect and ecosystem-based. Forest vegetation can reduce soil erosion, support infiltration, retain organic matter and provide habitat and microclimate functions. These functions can strengthen resilience to climate variability, heat and heavy rainfall, although the available case-specific evidence does not provide a quantified reduction in flood losses or heat mortality.

76The Park provides recreation, environmental education and opportunities for nature-based livelihoods.This forest stores carbon and also supports the carbon cycling. The 2026 soil study in BNP demonstrates that tree species influence soil respiration and carbon-related processes (Alam et al., 2026). This supports the broader climate-regulation argument, but it would be inappropriate to convert the study into a park-wide carbon sequestration estimate without a dedicated carbon inventory. Evidence of success and limitations of monitoring The evidence base demonstrates ecological value but also reveals a monitoring gap. There are recent bird surveys, soil-process research and remote-sensing studies, but there is no single, continuously updated public monitoring framework that combines biodiversity, forest cover, social well-being, tourism pressure, ecosystem services and climate resilience. This gap becomes especially important under IUCN Criterion 7, which requires regular monitoring, evaluation and adaptive management. IUCN NbS Self-Assessment The IUCN Global Standard consists of eight different criteria and associated indicators for assessing whether an intervention is a credible and sustainable NbS (IUCN, 2020). The assessment below is a desk-based case-study application using publicly available evidence. It should be treated as an academic assessment prepared for this report, not as an official IUCN certification or an electronically submitted score. Where evidence is unavailable, the score is intentionally conservative. The Scoring approach as follows: Strong = 3; Adequate = 2; Partial = 1; Insufficient evidence = 0. Scores are qualitative judgements based on the evidence reviewed. The purpose is to identify strengths and evidence gaps rather than create a false impression of precision. Criterion 1 – NbS has effectively addresses societal challenges: Strong (3/3). The central challenge of ecosystem degradation and biodiversity loss is clearly relevant, and BNP directly addresses it through protection and management. Human well-being benefits are also identifiable through recreation, education and livelihoods. The main weakness is that measurable well-being outcomes are not consistently benchmarked. Criterion 2 – The design of Nature-based Solutions (NbS) is appropriately informed by scale: Adequate (2/3). BNP is a landscape-scale protected area, and recent studies show that its condition is influenced by roads, population density, industrialization and surrounding land use. The existence of core and buffer management concepts also supports scale awareness. However, cross-boundary management with the wider Gazipur landscape remains difficult. Criterion 3 – Nature-based Solutions (NbS) lead to a net gain in biodiversity and the integrity of ecosystems. Partial (1/3). The Park clearly conserves biodiversity and continues to support substantial bird and plant diversity. Nevertheless, evidence of forest loss, fragmentation and historical replacement of native Sal Forest indicates that net ecological gain has not been demonstrated across the whole park. Recent restoration may provide local gains, but a current park-wide biodiversity baseline is lacking. Criterion 4 – NbS is economically viable: Partial (1/3). Tourism revenue and local economic activity demonstrate economic benefits, while conservation provides less easily monetized ecosystem services. However, publicly accessible evidence of full life-cycle costs, cost-effectiveness and comparison with alternative interventions is limited. This criterion therefore needs stronger financial analysis.

77Criterion 5 – Nature-based Solutions (NbS) which should be established on governance that is inclusive, transparent, and empowering. Partial (1/3). The Forest Department provides a formal institutional structure and management plans exist. However, earlier community studies reported limited participation and weak relationships between local communities and park administration. Governance can improve through co-management committees, transparent benefit-sharing and formal grievance mechanisms. Criterion 6 – NbS equitably balances trade-offs: Partial (1/3). BNP has clear trade-offs between conservation, visitor access, land rights, resource use, local livelihoods and development pressure. Earlier studies document these conflicts, but evidence of systematic, transparent and regularly reviewed trade-off safeguards is limited. This is one of the most important areas for improvement. Criterion 7 – NbS is managed adaptively, based on evidence: Adequate (2/3). The presence of recent bird, soil and remote-sensing studies shows that new evidence is being generated. Management plans also provide a basis for action. However, evidence is fragmented and not obviously integrated into a publicly documented monitoring-and-learning cycle with measurable triggers for changing management. Criterion 8 – Nature-based Solutions (NbS) are sustainable and integrated within the relevant jurisdictional context: Adequate (2/3). BNP is legally recognised, institutionally managed and supported by national protected-area planning. It contributes to biodiversity conservation, climate-related resilience and sustainable development objectives. Nevertheless, long-term sustainability is threatened by surrounding urbanization, road pressure and development, showing the need for stronger integration with district-level land-use planning. Overall, the assessment suggests a moderate but incomplete NbS performance. The strongest areas are the direct relevance of protected forest management to ecosystem degradation, the existence of formal governance structures and the continuing ecological benefits demonstrated by biodiversity research. The weakest areas are biodiversity net-gain evidence, economic cost-effectiveness, inclusive governance, and explicit management of trade-offs. The assessment therefore supports continued use of the NbS approach but calls for stronger monitoring, community participation and landscape-scale planning. Strengths, Limitations and Challenges The first major strength is that the intervention works with an existing ecosystem rather than replacing it with a wholly artificial structure. Protecting and restoring forest can generate multiple benefits simultaneously, including biodiversity conservation, recreation, soil protection and carbon-related functions. This multi-functionality is central to the NbS concept. Second, the Bhawal National park is strategically located near Dhaka and therefore has high public visibility. A protected forest in a rapidly urbanizing region can serve as a demonstration site for environmental education and urban-region resilience. Third, the park has also an established institutional framework and management plans, which provides a platform for improvement rather than requiring governance to start from zero. Lastly Fourth major strength, recent research provides an expanding evidence base. Bird surveys demonstrate biodiversity value, soil research shows below-ground ecological complexity, and geospatial studies identify spatial patterns of degradation. These sources can support more targeted management if they are integrated.

78The largest limitation is fragmentation and continued land-use pressure. A protected boundary cannot by itself prevent ecological impacts from roads, settlements, industries or surrounding development. The second limitation is incomplete restoration quality. Tree planting is not equivalent to restoration if it produces simplified stands or replaces native ecological structure with poorly selected species. Recent soil research supports a more ecological approach to species selection. A third limitation is the weakness of publicly accessible, integrated monitoring. Without a current biodiversity inventory, forest- condition baseline, visitor-pressure indicators, social indicators and ecosystem-service measures, it is difficult to quantify whether the park is improving or deteriorating over time. The application must balance out the conservation with the needs of people who are living around the park. Restricting access without alternatives can increase conflict or illegal use. Conversely, excessive access can undermine conservation. The solution requires participatory zoning, livelihood support, transparent rules and enforcement that is perceived as fair. Tourism is yet another challenge. Because Bhawal National Park is unrestricted and very near to Dhaka, visitor pressure can intensify in a particular seasons and locations. Management should therefore use visitor-capacity assessments, designated routes, waste controls, noise restrictions and monitoring of sensitive habitats. Climate change adds uncertainty. Changes in rainfall, temperature and extreme events may alter tree growth, fire risk, pest dynamics and water availability. Adaptive management is therefore necessary rather than a fixed plan that is never revised. A major risk is that tourism revenue becomes a stronger management priority than the ecological integrity. Another is the replacement of native forest with some exotic plantations because planted trees are easier to establish or grow quickly. This may increase tree cover while failing to restore biodiversity or ecological function. A further risk is exclusion: if local residents are treated only as threats rather than stakeholders, conservation restrictions can deepen conflict and reduce compliance. The Equity concerns are especially more important under IUCN Criteria 5 and 6. People with fewer substitution for livelihood options may bear a larger share of strict conservation regulations, while visitors and urban residents may receive a larger share of recreational benefits. A fair NbS should therefore make the distribution of benefits and costs explicit and provide mechanisms for participation and grievance resolution. Reccomendations The recommendations focus on establishing a park-wide biodiversity and ecosystem-condition baseline covering vegetation, birds, mammals, soil, water bodies, invasive species, and habitat connectivity, and on creating a public annual monitoring dashboard using satellite forest-cover data, biodiversity surveys, visitor counts, and community indicators. To strengthen governance, community co-management should be reinforced by giving local representatives defined roles in planning, monitoring, and conflict resolution, alongside transparent benefit-sharing mechanisms so that conservation-compatible tourism and livelihood opportunities reach affected communities. Ecological priorities should center on native Sal-forest restoration and ecological integrity rather than relying on tree-planting totals as the main success indicator, while high-use sites require visitor zoning and carrying-capacity assessment, especially during winter. Finally, BNP conservation should be integrated with Gazipur district land-use planning, road development decisions, and industrial environmental assessment; the IUCN self- assessment should be repeated periodically, for example every three years, to identify management priorities; explicit safeguards and an accessible grievance mechanism should be developed for land and resource-use conflicts; and a cost-effectiveness study should be commissioned comparing restoration, protection, co-management, and alternative land-use scenarios.

79Conclusion Bhawal National Park is a well-studied and strong example of how protected forest ecosystems can function as a local Nature-based Solution when conservation, restoration and sustainable use are connected to human well-being. Its most important contribution is the protection of a remaining Sal- forest landscape within a rapidly urbanizing region. The Park continues to support substantial biodiversity, including at least 138 recorded bird species in a recent survey, and it supports ecological processes such as soil carbon cycling (Jaman et al., 2024; Alam et al., 2026). It also provides recreation and economic opportunities. However, the case also demonstrates that simply declaring an area protected is not enough to guarantee a successful NbS. Forest loss, fragmentation, tourism pressure, development, community conflicts and incomplete monitoring reduce the effectiveness and sustainability of the intervention. The IUCN assessment therefore gives a mixed result: strong relevance to the societal challenge, but only partial performance in biodiversity net gain, economic feasibility, inclusive governance and trade-off management. The most important future direction is to shift from protection of a boundary to integrated landscape stewardship. BNP should be managed as part of the wider Gazipur social-ecological system, with stronger community participation, ecological restoration, evidence-based monitoring and coordination with land-use planning. With these improvements, the park's NbS approach could be strengthened and potentially adapted to other fragmented Sal-forest landscapes in Bangladesh. Its value lies not in being a perfect solution, but in demonstrating how nature can remain part of disaster-risk reduction, climate resilience, biodiversity conservation and human well-being when management is continuous, inclusive and evidence based. References Abdullah, M., Jusoff, K., Sheikh, A. H., & Yaman, A. R. (2009). The management of Bhawal National Park, Bangladesh by the local community for resource protection and ecotourism. Asian Social Science, 4(7). https://doi.org/10.5539/ass.v4n7p101 Alam, M. A., Rasif, T. C., Kamal, L., Rahaman, M. A., Pramanik, M. M. M., Ahmed, I., Hossain, M. F., & Ahmed, A. (2026). Species specific controls on rhizosphere soil respiration in a tropical deciduous forest of Bangladesh. Plant Environment Interactions. https://doi.org/10.1002/pei3.70200 Alauddin, M., Hossain, M. N., Islam, M. B., Islam, S., & Islam, M. K. (2020). Sustainable forest biodiversity conservation management strategies in protected areas of Bangladesh: A study of Gazipur's Bhawal National Park. Grassroots Journal of Natural Resources, 3(3), 56–72. https://doi.org/10.33002/nr2581.6853.03035 Bangladesh Forest Department. (2025). Protected area management plans: Bhawal National Park management plan 2015–2025 and Bhawal National Park ecotourism management plan 2015–2025. Ministry of Environment, Forest and Climate Change. https://bforest.gov.bd/pages/static-pages/6922dcec933eb65569e12c49 Chakraborty, P., & Talukder, P. C. (2026). Mapping deforestation probability and understanding the forest dynamics in Gazipur, Bangladesh. Environmental Challenges, 24, 101568. https://doi.org/10.1016/j.envc.2026.101568 Food and Agriculture Organization. (2000). Forest resources of Bangladesh: Country report. FAO. https://www.fao.org/4/ad104e/ad104e04.htm Integrated Protected Area Co-management. (2010). State of Bangladesh's forest protected areas, 2010. USAID/Bangladesh and Bangladesh Forest Department. International Union for Conservation of Nature. (2020). The user-friendly framework for the verification, design, and scaling up of Nature-based Solutions: IUCN Global Standard (1st ed.). IUCN.https://doi.org/10.2305/IUCN.CH.2020.08.en International Union for Conservation of Nature. (2020). First edition of the Guidance for using the IUCN Global Standard for Nature-based Solutions. IUCN. https://doi.org/10.2305/IUCN.CH.2020.09.en Rabbe, M. F., Tareq, M. H., Ilma, U. H., Mia, T., Alam, M. M., Shome, A. R., & Jaman, M. F. (2024). Unveiling the avian species in the sal forest of central Bangladesh exhibits habitat preferences, community structures, and conservation concerns, as discussed in the article published in the Dhaka University Journal of Biological Sciences, 33(1), 1–21. https://doi.org/10.3329/dujbs.v33i1.72460

11 Nature-Based Solutions (NbS): A Local Case Study of The Norai River as an Unplanned Nature-Based Solution Naoshin Jahan BusraAbstract Urban flooding and the progressive loss of natural drainage capacity have become defining disaster risks for rapidly urbanizing cities in the Global South, and Dhaka is a leading example of this trend. As the city has expanded outward from its historic core, its network of canals and rivers once responsible for carrying excess rainwater away during the monsoon has been steadily narrowed, encroached upon, and in many cases filled in to make way for residential and commercial development. This loss of drainage infrastructure has direct consequences for millions of urban residents, who face recurring waterlogging, property damage, and public health risks whenever heavy rainfall exceeds the reduced carrying capacity of what remains of the city's waterways. Keywords: Norai River; Disaster ManagementDepartment of Disaster Management and Environmental Studies, Brac University, BangladeshIntroduction This problem is examined here through the case of the Norai River, a narrow waterway running approximately six kilometres through the Rampura-Aftabnagar area of eastern Dhaka before joining the Balu River. Once navigable and central to the livelihoods of surrounding communities, the Norai has been reduced to a fraction of its original width by decades of land-filling and construction encroachment (Chowdhooree et al., 2025; UNB, 2025). It survives today primarily because it continues to carry stormwater and pump station discharge for a catchment of roughly five million residents (Chowdhooree et al., 2025) not because it was ever deliberately designed or managed as a nature-based solution. This makes the Norai a particularly instructive, if imperfect, case: an accidental Nature-Based Solution that delivers one real disaster-risk benefit flood and waterlogging mitigation while the same urban pressures that created the need for that benefit continue to erode the river's capacity to provide it. This paper investigates the environmental, social, and economic conditions that have shaped the Norai's current role, examines the available evidence on its effectiveness and impacts, and applies the IUCN Global Standard for Nature-based Solutions Self-Assessment Tool to critically assess its performance across the eight IUCN criteria. In doing so, it aims to determine how well the Norai currently functions as an unplanned flood mitigation measure, where its evidence gaps and shortcomings lie, and what this reveals about the broader challenge of managing accidental NbS within dense, rapidly growing urban environments along with what deliberate improvements could strengthen it going forward.80

81The Norai River serves as an important case study of how rapid urbanization, drainage encroachment, and urban flood risk interact. Today the Norai River functions mainly as a drainage channel. The waterfront development project has had only a moderate environmental impact, with its main measurable benefit being a reduced risk of waterlogging in the surrounding area (Chowdhooree et al., 2025). Decades of narrowing have sharply cut the river's drainage capacity. Once wide enough for boats carrying goods from Aftabnagar to local markets, the Norai has shrunk drastically due to land-filling on both banks (UNB, 2025). Continuing encroachment compounds the problem: a recent site visit found construction waste dumped into the channel, along with parked vehicles and other structures occupying the riverbed (UNB, 2025). Each of these reductions in channel width limits the space available to carry stormwater during peak monsoon flow, directly undermining the flood-control function the nature- based solution is meant to provide. Residents of Banasree and Aftabnagar have lost the river as both a resource and a livelihood. One long- term resident recalled commuting by boat from Aftabnagar to school in 1991 and buying fishing gear at a riverside market, both now gone under land-filling (UNB, 2025). Earlier reporting estimated that thousands of people across Khilgaon and Trimohini faced daily exposure to toxic gas emissions from the polluted water, putting boatmen, farmers, and nearby residents at direct risk of respiratory and skin illness (Chowdhury, 2012). Water quality testing later confirmed severe, multi-parameter contamination well beyond safe thresholds (Roy et al., 2014), consistent with the near-total fish loss that residents and boatmen describe. The Environment Conservation Act 1995 requires polluters to prevent or mitigate discharge, with penalties of up to ten years' imprisonment or a Tk. 1 million fine (Arifuzzaman et al., 2019), yet enforcement remains weak: the Department of Environment operates in only 23 districts and is chronically understaffed (Arifuzzaman et al., 2019), while BAPA has repeatedly demanded an end to sewage dumping into the Norai (Chowdhury, 2012; UNB, 2025). Institutional responsibility is fragmented across RAJUK, DNCC, DSCC, and Dhaka WASA, with no single body held accountable (UNB, 2025); the National River Protection Commission Act 2013 created an advisory body following a 2010 High Court order to protect Dhaka's four major rivers, but it holds no statutory enforcement power (Arifuzzaman et al., 2019), and the Dasherkandi Sewage Treatment Plant, built to treat Hatirjhil-Norai wastewater, does not cover all connected canals (UNB, 2025). The primary academic anchor for this case is Chowdhooree et al. (2025), which assessed the Norai waterfront as an NbS, finding moderate environmental performance but limited social and economic livability gains, discussed further in later sections. Description of the Nature-Based Solution The Nature-based Solution (NbS) examined here is the Norai River waterfront intervention. It uses the river as a water-management feature to support urban drainage and reduce waterlogging. Rather than treating the river simply as a body of water, the intervention relies on its natural capacity to carry and manage excess stormwater within the city. The Norai now functions mainly as a drainage channel, moving stormwater from Rampura and Aftabnagar, along with discharge from the Rampura pump station, toward the Balu River (Chowdhooree et al., 2025). By preserving the channel and its drainage role, the intervention allows rainwater to flow through a natural waterway rather than relying solely on conventional drainage infrastructure. However, the river's capacity has shrunk as its banks have narrowed and been built over, limiting the space available for stormwater flow (Chowdhooree et al., 2025).

82The Norai River waterfront is located in Dhaka, with the study area covering roughly 2 kilometres along both sides of the narrow channel, running parallel to Bir Uttam Rafiqul Islam Avenue and connecting to Hatirjhil Lake; after flowing more than 6 kilometres eastward, the river meets the Balu River, which marks Dhaka's eastern boundary (Chowdhooree et al., 2025). Administratively, the area falls under Wards 21 and 22 of Dhaka North City Corporation and Ward 3 of Dhaka South City Corporation, and spans the Badda and Rampura police station jurisdictions (Chowdhooree et al., 2025) — a split that matters because no single city corporation controls the river's full physical extent. The surrounding land is mainly residential, comprising the Banashree and Aftabnagar (Jahurul Islam City) developments, though commercial activity is expanding along the roads and into the ground floors of residential buildings, and more than 5 million people live in the wider catchment area that drains toward this stretch of the river (Chowdhooree et al., 2025). The river's shrinkage is well documented on maps: much of this corridor was low-lying floodplain as recently as the 1980s, and large-scale land-filling began in the late 1990s and has continued spreading toward Dhaka's eastern fringe (Chowdhooree et al., 2025), a pattern that matches broader studies of canal encroachment across Dhaka, where urban growth has steadily reduced the width and connectivity of waterways (Ishtiaque et al., 2014). Origin of the NbS Norai River (also spelled Narai) originally ran from western Karwan Bazar, connecting the Turag River in the west to the Balu River in the east (Wikipedia, n.d.). Its current form is the product of decades of encroachment rather than a single planned NbS project. In 1991, people still used boats to travel the Norai between Aftabnagar and Banashree. Private housing began filling in the land through the 1990s, building on earlier encroachment that started during the Ershad regime in the 1980s (Chowdhooree et al., 2025; UNB, 2025). The channel that survives today was preserved mainly because drainage was needed; even the official classification of the Norai as a "river" rather than a canal required deliberate institutional effort (UNB, 2025). This reactive pattern matches the other waterfront projects in Dhaka. Zaman et al. (2024) found that such projects usually aim to restore drainage and clear encroachment rather than to restore ecosystems. The Norai follows this same logic: it was preserved out of necessity, not built as a Nature- based Solutions project from the start. The main beneficiaries are the roughly five million residents living in the catchment area, whose homes depend on the river's ability to drain water and limit flooding during the monsoon season (Chowdhooree et al., 2025); this benefit is diffuse and citywide rather than the result of a targeted plan, since residents gain flood protection without engaging directly with the river, unlike NbS models elsewhere that involve communities actively managing green-blue spaces (IUCN, 2025). A smaller group still uses the river actively: boat operators continue moving construction supplies, sand, and vegetables along the channel, sustaining a version of its old role in local trade, while some residents also use the riverbanks informally, mainly for waste disposal, recreation, or income generation (Chowdhooree et al., 2025; UNB, 2025). Ecologically, however, the river's aquatic life is severely degraded rather than healthy—water testing shows dissolved oxygen levels too low to sustain fish (Roy et al., 2014)—and the only ecosystem function still operating is drainage, not habitat provision, with the remaining green strips along the banks providing only minimal plant cover and no evidence of any plan to enhance biodiversity or restore habitat (Chowdhooree et al., 2025).

83Evidence and Impacts Water quality testing along the Narai canal found conditions unsuitable for life on every measured parameter except pH: dissolved oxygen ranged from just 0.33 to 2.12 ppm, far below the 5.0 ppm threshold considered safe for fisheries, confirming the fish population collapse those local boatmen had long reported anecdotally, while total dissolved solids reached 1,308 mg/L—more than double the 500 mg/L domestic-use limit—and ammonium peaked at nearly 90 mg/L against a 30 mg/L irrigation threshold, largely due to untreated industrial effluent from over 300 units in nearby Tejgaon (Roy et al., 2014). Despite this pollution, the intervention's core environmental function, maintaining channel capacity for drainage, has produced some measurable benefit: a formal assessment rated the waterfront project's environmental performance as moderate, attributing this specifically to reduced waterlogging risk rather than to any improvement in water quality or biodiversity (Chowdhooree et al., 2025). In short, the NbS delivers a narrow, drainage-focused environmental benefit, while the broader aquatic ecosystem it occupies remains severely degraded. Beyond the loss of livelihoods discussed above, a formal assessment shows that the waterfront intervention creates little real social value: despite running through a dense residential area, the project has failed to build shared spaces or bring people together (Chowdhooree et al., 2025), and there are no public areas along the water's edge—no walkways, benches, or gathering spaces—leaving the river corridor feeling invisible to the neighborhoods it passes through. Where public space should exist, informal and often negative uses have taken over, with site observations finding parts of the riverbank occupied by makeshift shelters and piles of trash rather than community use (Figure X), and nearby open areas functioning as dumping grounds, complete with city corporation signs directing residents to dispose of waste in "designated places"—evidence of an ongoing, unresolved conflict between residents and authorities over waste management. The result is a social impact gap rather than a benefit: the project did not displace anyone to build infrastructure, but it also failed to convert the river's central location into a shared community asset, missing an opportunity that similar nature-based solutions elsewhere have achieved through thoughtful design (IUCN, 2025). The river's economic role today is minimal: small boats still carry construction materials, sand, and vegetables a remnant of the trade the river once supported (Chowdhooree et al., 2025)—but formal assessment identifies economic activity as one of the intervention's weakest areas, with no new markets, businesses, or livelihoods having emerged from the waterfront itself (Chowdhooree et al., 2025), and nearby growth in shops, hospitals, and property values driven by broader urbanization rather than by the river (UNB, 2025). Pollution adds further cost, as contaminated water limits irrigation use and collapsed fish populations have eliminated a livelihood source (Roy et al., 2014), leaving the net economic impact close to zero or mildly negative.

This drainage function, described in Section 3.1, is central to the intervention's disaster risk reduction role, and formal assessment credits the project's environmental performance score mainly to its reduction of waterlogging risk—its main measurable achievement (Chowdhooree et al., 2025). However, this capacity is being steadily eroded: the channel has narrowed to just 25 metres due to ongoing land- filling and encroachment, and a recent site investigation found construction waste and structures still being dumped directly into the riverbed (UNB, 2025), so every further loss of width reduces the river's stormwater capacity during peak monsoon flow and undermines the very function the NbS is preserved to provide. The central paradox is that the river survives because of its drainage role, yet the same urban pressures that create the need for drainage are also destroying the river's capacity to deliver it. IUCN NbS Self-Assessment This assessment applies the IUCN Global Standard for Nature-based Solutions Self-Assessment Tool to the Norai River waterfront, evaluating how well it addresses flooding and drainage problems in Rampura-Aftabnagar, drawing on two sources: existing research and our own site observations. We reviewed water quality data from Roy et al. (2014), the NbS assessment by Chowdhooree et al. (2025), and reporting from UNB (2025), supplemented by a site visit in August 2026, during which we photographed the river channel's width, the extent of water hyacinth growth, and signs of illegal construction or use. The scoring focuses primarily on flood and drainage risk reduction while also revealing where the project falls short including wildlife support, inclusive community engagement, and economic benefit shortcomings consistent with the findings in Section 4. The completed self-assessment produced an overall score of 19 out of 147 points (13%), rated "Insufficient" across all eight criteria (see Table 3 / Appendix A for the full breakdown). Performance was highly uneven: Criterion 1 (societal challenges) scored highest at 33% (6/18), while Criterion 4 (financial feasibility) and Criterion 6 (balancing goals and impacts) both scored 0% (0/15), the lowest possible result. Criteria 2, 3, 7, and 8 fell between 11% and 20%, and Criterion 5 (inclusive governance and equity) scored just 4% (1/27), the second-lowest result and, given its high maximum weighting of 27 points, one of the most consequential gaps overall. This distribution confirms the pattern running through the paper: the Norai delivers one measurable benefit, flood and waterlogging mitigation, while lacking almost every structural element the IUCN Standard associates with a well-designed, sustainable NbS.84

85The Norai's one clear strength is Criterion 1, addressing a real and significant societal challenge. Unlike most other criteria, this is backed by concrete evidence rather than assumption: the channel actively carries stormwater and pump-station discharge away from a densely populated catchment, and Chowdhooree et al. (2025) attribute a measurable reduction in waterlogging risk specifically to this preserved drainage function. This is a meaningful achievement given the scale of the population protected, and it explains why the channel has survived, even informally, despite decades of encroachment pressure. It remains, however, the only criterion where the evidence points to strong performance For the Norai River, evidence is limited or absent across most remaining criteria: economic viability, inclusive governance, adaptive management, and long-term sustainability. No project-specific data exists on cost-benefit performance, community participation, regular monitoring, or an adaptive- management system, and there is no documented evidence of biodiversity gains or formal integration into long-term urban planning (Chowdhooree et al., 2025; UNB, 2025). This is not simply an information gap; it reflects the fact that the Norai was never established through a process that would generate this kind of evidence in the first place (Section 3.3). Because the IUCN Standard requires demonstrated evidence across all eight criteria rather than a single strong result, these gaps meaningfully limit how the intervention can be scored overall (IUCN, 2020). Strengths, Limitations and Challenges The Norai's main strength is narrow but real: it continues to provide catchment-wide flood and waterlogging protection for an estimated five million residents, despite receiving no deliberate design, investment, or management attention (Chowdhooree et al., 2025). This benefit has persisted for decades simply because the channel's drainage role gave authorities and residents a practical reason not to fill it in entirely, even as everything around it was built over; in IUCN terms, this is a genuine, evidence-supported response to a real societal challenge flood risk the foundation any NbS assessment must start from. The case also holds analytical value: because the intervention is unplanned, it offers an unusually clear illustration of what an NbS looks like when only one function is preserved while every other potential benefit—biodiversity, public space, economic activity, community governance is allowed to erode, a contrast that is instructive for understanding what deliberate NbS design would need to address. The Norai's core limitation is that it was never designed as a holistic NbS, it survives as a drainage channel by necessity, not intention. This shows up across every dimension except flood risk: near-total loss of aquatic life from pollution (Roy et al., 2014), no usable public space despite running through a dense residential area, and negligible economic contribution beyond small-scale boat trade. Implementation is further undermined by fragmented governance: no single authority is accountable for the river across RAJUK, DNCC, DSCC, and WASA, which helps explain why encroachment continues even as officials acknowledge the problem (UNB, 2025). Site observation confirms this is ongoing rather than historical: active construction and waste dumping were directly visible during the August 2026 visit. Costs and benefits are unevenly distributed: flood protection benefits residents fairly equally (Chowdhooree et al., 2025), yet degradation burdens the river and informal users, while formal development expands without bearing that cost. Figure 4 shows construction invading the riverbank beside high-rises, further narrowing the channel and reducing the drainage capacity residents depend on.

86This paper has examined the Norai River waterfront as a case of an accidental Nature-based Solution, a natural feature that continues to deliver a real disaster-risk benefit despite never being deliberately designed or managed as one. The evidence points to a consistent pattern: the Norai performs well on a single function, flood and waterlogging mitigation, while falling short across nearly every other dimension an NbS is expected to deliver, its aquatic ecosystem has effectively collapsed, it generates no meaningful public or economic value, and no single institution is accountable for its protection. This is the case's central paradox: the same urban growth that makes the river's drainage function indispensable is also the force steadily narrowing its capacity to provide it. Left unaddressed, this erosion is likely to continue.The Norai's overall effectiveness is therefore best described as narrow rather than genuinely successful, a partial benefit sustained by necessity, not policy. Even so, targeted, low-cost measures such as riparian buffer restoration and bioswales could strengthen its ecological and resilience performance without disrupting its drainage role, provided they are paired with clearer governance and stronger enforcement against encroachment. More broadly, the Norai reflects a pattern likely to recur across other encroached waterways in Dhaka, making it a useful and replicable starting point for rethinking how the city manages its remaining canals and rivers. References Chowdhooree, I., Bhuyan, M. R., & Aziz, T. (2025). Sustainable urban development and nature-based solutions: An assessment of the developments along Norai River banks in Dhaka [Preprint]. Research Square. https://doi.org/10.21203/rs.3.rs-7361633/v1 Roy, S., Banna, L. N., Hossain, M., & Rahman, H. (2014). Water quality of Narai canal and Balu river of Dhaka City: An impact of industrialization. Journal of the Bangladesh Agricultural University, 12(2), 285–290. Arifuzzaman, M., Hannan, M. A., Rahman, M. R., & Rahman, M. A. (2019). Laws regulating water pollution in Bangladesh. Journal of Sociology and Anthropology, 3(1). IUCN (International Union for Conservation of Nature). (2020). Global standard for nature-based solutions: A user-friendly framework for the verification, design and scaling up of NbS. IUCN. https://www.iucn.org/resources/publication/global-standard-nature-based-solutions IUCN (International Union for Conservation of Nature). (n.d.). Self-assessment tool for the IUCN Global Standard for Nature-based Solutions. Retrieved , from https://inbs.iucn.org/apply/nature-based-solutions-self-assessment/tool

12 Ecosystem Restoration and Nature-Based Solution (NbS) Master Plan for the National Botanical Garden of Bangladesh Md Tamjid Alam Chowdhury, Humayra Khan, & Songbith Joutho KabirAbstract The National Botanical Garden (NBG) of Bangladesh is located in the urban area of Mirpur, Dhaka and covers about 208 acres (84 hectares) of urban ecology landscape. Founded in 1961 as a central sanctuary for ex-situ plant conservation, systematic botanical research, and public education, the NBG has been severely degraded. Rapid, unplanned urbanization in Greater Dhaka, compound climate hazards, thermal anomalies, severe stormwater runoff, atmospheric pollution, and historic eco- engineering missteps have degraded the ecological integrity of the 57 management blocks of NBG.This report presents a structured plan for fixing, restoring and future-proofing the National Botanical Garden using a Nature-based Solution framework in line with the International Union of Conservation of Nature (IUCN) Global Standard for NbS. The proposed intervention replaces grey infrastructure interventions with bio-adapted hydraulic engineering, native canopy reforestation, habitat connectivity corridors and inclusive co-governance models. Through a multi-phase restoration program that has been evaluated against the 8 IUCN NbS criteria, this report details how the NBG can be transformed from a deteriorating green space into a resilient urban ecological anchor that can mitigate disaster risks, sequester urban carbon, cool Mirpur's microclimate and safeguard Bangladesh's plant genetic resources. Keywords: National Botanical Garden Bangladesh; Disaster ManagementDepartment of Disaster Management and Environmental Studies, Brac University, BangladeshIntroduction Metropolitan Dhaka is one of the densest urban agglomerations in the world as it accommodates over 22 million residents in an environment of concrete, structural grey infrastructure and fragmented wetlands. Within this concrete expanse, the National Botanical Garden (NBG) in Mirpur serves as a crucial green lung and central genetic repository of the country's flora. However, decades of surrounding urbanization have isolated the garden, turning an active ecological buffer into a vulnerable eco-island. To address the ecological crisis associated with NBG it is no longer sufficient to just adopt standard horticultural management. Instead, the need is for a comprehensive Nature-based Solution framework that can restore natural ecosystem functions, optimize water cycles, mitigate climate associated risks and establish sustainable and inclusive governance. This report outlines the environmental challenges affecting NBG, details a technical ecosystem restoration intervention, evaluates the solution using the 8 IUCN NbS Criteria, and presents a long-term strategic implementation roadmap.87

88The National Botanical Garden of Bangladesh is located in the Mirpur division of Dhaka, adjacent to the Bangladesh National Zoo, and bounded to the west by the Turag River floodplain 23.811 North, 90.347 East. Geologically, the site lies within the Pleistocene terrace structure of the Madhupur Tract. The terrain is characterized by gentle undulations, and not steep relief, with soils primarily consisting of deeply weathered, reddish-brown clays rich in iron and aluminum sesquioxide. Surrounding these upland terraces are low-lying alluvial plains historically connected to the Turag River hydrological network. The region is characterized with tropical monsoon climate with three distinct seasons; hot and humid summer (March to May), monsoon season with heavy rainfall (June to October) and a mild, dry winter (November to February). The average annual precipitation exceeds 2,000 mm, with more than 80% falling during the monsoons. The mean ambient temperatures range between 12°C in winter and extreme summer peaks of 38°C-40°C. The Capital Dhaka has encountered disruption on the geological & ecological systems due to rapid urbanization. Botanical Garden being a part of the capital faces ecological barriers and undergoes damages of its infrastructure. The rapid conversion of natural landscapes to dense urban infrastructure within Mirpur has amplified the Urban Heat Island (UHI) effect. Paved surfaces absorb and radiate thermal energy creating ambient temperatures of 3°C to 6°C higher in surrounding residential blocks comparing to non-urbanized areas. While NBG acts as a local thermal sink the surrounding heat belt exerts severe physiological stress on sensitive plant species, altering flowering schedules, disrupt plant-pollinator interactions and cause thermal damage to delicate native plant species. Mirpur has high levels of ambient air pollution due to construction dust, brick kilns and dense vehicular traffic along primary arterial roads. Fine particulate matter PM2.5 and PM10 along with heavy metal compounds have accumulated on the leaf canopy across the garden's border blocks. This particulate crust causes limited gas exchange, reduced photosynthetic capacity and weakens vegetative growth. Concomitantly, native plant biodiversity has declined due to the historic introduction of fast-growing, non-native species (such as Eucalyptus and Acacia spp.). These invasive species compete with native understory flora for groundwater and soil nutrients, lowering structural diversity and displacing local fauna, including native insect, bird and amphibian populations.

Urban expansion around Mirpur have disrupted natural drainage channels causing high volumes of polluted, uncontrolled urban runoff to discharge towards the garden's low-lying zones during heavy monsoon downpours. The site's reddish-brown clay soils have low infiltration rates when saturated. Combined with hardened, non-porous internal walkways and altered natural lake margins, monsoon downpours cause prolonged waterlogging in low-lying blocks. This drowns root systems not adapted to being submerged for long periods of time, erodes soil and washes urban pollutants into the garden's internal aquatic ecosystems. The environmental degradation of NBG affects multiple ecological and socio-economic sectors: Local Urban Residents: Over 1.3 million inhabitants of Mirpur and the broader Dhaka region relies on NBG as a primary public green space for recreation, physical health and relief from urban heat and pollution. Scientific and Academic Community: Botanists, researchers and university students rely on the National Herbarium and living collections for plant taxonomy, conservation genetics and ecological research. Degradation of rare plant collections impacts the national research capacity. Urban Agriculture and Horticulture: Surrounding nurseries and local urban agricultural efforts rely on the regional microclimate and pollinator populations maintained by the garden's habitat blocks. Institutional Governance: The Bangladesh Forest Department and the Ministry of Environment, Forest and Climate Change (MoEFCC) are facing mounting management challenges as traditional horticultural strategies no longer address complex climate impacts. The strategic restoration plan aligns with several national policy and environmental frameworks: National Adaptation Plan (NAP) of Bangladesh (2023-2050): Emphasizes the need of incorporating NbS to build urban climate resilience, flood protection and heat stress reduction. National Biodiversity Strategy and Action Plan: Mandates the expansion of ex-situ conservation, habitat restoration and protection of threatened native flora.Bangladesh Climate Change Strategy and Action Plan (BCCSAP): Priority is given to ecosystem-based adaptation, urban forestry and water resource management. Master Plan Update & Ecosystem Conservation of NBG (2021/2022 Initiative): Structural framework from the Forest Department to improve facilities, conservation blocks and environmental performance across the garden. Description Of the Nature-Based Solution (Nbs) The proposed intervention transforms the entire 208 acres site into an integrated Nature-based Solution (NbS). Rather than using hard engineering interventions like concrete retaining walls and artificial paved surfaces, the plan applies ecological design across all 57 management blocks89

The site utilizes an integrated Nature-based Solutions (NbS) approach to manage urban runoff and stormwater. The system begins with bioswales and vegetated sinks that direct water into sedimentation ponds and subsurface infiltration areas. From there, the water moves through a bio-engineered wetland before finally entering the internal lake network. The internal path network will be upgraded with permeable eco-pavements, porous gravel pathways, and elevated timber boardwalks over sensitive wetland zones. This transition eliminates surface sealing and increases rainwater infiltration directly into the underlying Pleistocene clay aquifer. Furthermore, these materials reduce surface runoff velocity and eliminate root compression beneath major tree canopies. The site's six internal lakes and aquatic channels will undergo bio-engineering restoration. Hardened edges will be removed and replaced with bio-engineered slopes stabilized by native deep-rooting vegetation such as Vetiveria zizanioides, native reed beds, and coconut coir rolls. A series of tiered bioswales, retention basins, and constructed wetlands will treat incoming urban stormwater. Native macrophyte species like Typha domingensis, Phragmites australis, and Hydrilla verticillata will filter nutrients, heavy metals, and suspended solids before the water enters the primary lakes. Additionally, low-voltage solar pumping systems will circulate water between connected lakes to prevent stagnation, maintain dissolved oxygen levels above 6.0 mg/L, and eliminate toxic algal blooms. The main rationale for adopting an NbS approach is to restore the self-regulating ecological capacities of the landscape rather than relying on ongoing grey infrastructure maintenance. The main objectives of this approach include achieving a local microclimate cooling drop of 1.5C to 2.5C, ensuring 100% on-site stormwater retention, recovering native biodiversity with 300+ native species, and establishing sustainable visitor management and governance. Direct beneficiaries include nearby Mirpur residents who will benefit from a healthy green belt, improved air quality, and reduced localized heat stress. Indirect beneficiaries include the greater Dhaka urban area, which will see increased flood detention capacity in the Turag basin and mitigation of the urban heat island effect. Institutional beneficiaries include the Bangladesh Forest Department, universities, and researchers who will gain an improved research station for ecological studies. The site supports four primary ecosystems: terrestrial red-brown clay terrace forests, freshwater connected lakes and ponds, palustrine seasonally inundated marshes and swales, and an urban fringe buffer of multi-layered greenbelts for dust and noise abatement.90

91The botanical garden mitigates environmental problems in four main ways. First, it prevents extinction by storing seeds and cultivating endangered plants for ex situ conservation to protect plant genetic diversity. Second, it restores ecosystems by growing native species to reintroduce them into degraded habitats and help control invasive plant species. Third, it combats climate change by researching heat and drought-tolerant plants while acting as an urban green space that cools cities and absorbs carbon. Finally, it educates the public by hosting educational programs and community science projects to raise awareness about biodiversity loss. The implementation of bio-engineered wetlands and restoration of native canopies across urban botanical gardens have demonstrated ecological returns, with improved stability in the soil moisture profile during dry spells and reduced peak outflow velocities for storm events. Replacing monoculture stands with native species increases avian, insect, and soil microbial diversity, establishing balanced food webs that help naturally regulate herbivore pests. Urban natural spaces reduce stress and promote community well-being. Improved internal access using low-impact trails and informative ecological signage transforms the site into an accessible outdoor classroom. Local urban communities benefit from a cooler recreational area and increased civic engagement through participation in the garden's ecosystem restoration activities. While hard engineering solutions require significant capital repairs and energy-costly maintenance, Nature-based Solutions reduce operational expenditures after initial installation. Natural water filtration through phytoremediation reduces the need for motorized treatment facilities, and stabilized banks reduce repair costs related to erosion. Upgraded eco-tourism infrastructure provides sustainable revenues from admission fees, research grants, and educational events to support continued management of the site. The expansion of internal wetlands for increased storage capacity provides over 150,000 m3 of flood retention during extreme monsoon events, reducing the risk of localized urban flooding for residential areas in Mirpur. Increased canopy coverage in combination with surface-water evapotranspiration acts as a microclimate cooler, reducing heat stress on the region during extreme summer heatwaves. Additionally, replacing short-lived exotic trees with long-lived native hardwoods improves long-term carbon sequestration in both vegetation and soil. Pilot initiatives across South Asia have demonstrated that the inclusion of constructed bioswales and native vegetation buffers delivers rapid environmental improvements. Pilot monitoring data shows that native wetland flora can remove up to 80% of suspended solids and 60% of nitrates from urban runoff within 48 hours of retention. Furthermore, the replacement of non-native Eucalyptus stands with native species has been shown to increase local groundwater levels within three to five years, demonstrating the potential for large-scale ecological restoration. IUCN NbS Self-Assessment Criterion 1: Societal Challenges Target Challenges: Urban heat stress, severe flash flooding, air pollution, loss of native plant genetic resources (Halder, 2020; MoEFCC, 2023). Test Score: 11 / 18 (61%) Assessment Result: Adequate (IUCN, 2020) Justification: The project directly addresses key urban vulnerabilities faced by Dhaka's population by providing flood attenuation, microclimate cooling, air filtration within the Mirpur's dense urban footprint (Global Center on Adaptation & IUCN Bangladesh, 2025; MoEFCC, 2023).

92Criterion 2: Integrated Systems Perspective Systemic Integration: Connects the internal 208-acre landscape with the wider Turag River basin and Mirpur urban corridor (Bangladesh Forest Department, 2019; Vitti Government Projects Division, 2021). Test Score: 7 / 18 (39%) Assessment Result: Insufficient (IUCN, 2020) Justification: Internal site measures are well-conceived but external watershed dynamics, regional air sheds, external municipal runoff vectors outside the garden's boundaries are inadequately integrated within current landscape planning (Chowdhury, 2025; The Business Standard, 2025). Criterion 3: Enhanced Biodiversity and Ecosystem Integrity Biodiversity Net Gain: Phased removal of invasive exotics, enrichment planting of over 300 threatened native species, comprehensive wetland restoration (Bangladesh Forest Department, 2019; Halder, 2020). Test Score: 12 / 21 (57%) Assessment Result: Partial (IUCN, 2020) Justification: Restoration efforts contribute towards protecting native floral genepools and aquatic habitats, however, long term monitoring mechanisms to verify sustained post-intervention ecosystem net gains require further strengthening (Halder, 2020; IUCN, 2020). Criterion 4: Financial Feasibility & Economic Justification Financial Model: Phased capital development funded by national adaptation allocations, offset by reduced ongoing maintenance costs and eco-tourism revenue (Bangladesh Forest Department, 2019; MoEFCC, 2023). Test Score: 7 / 15 (47%) Assessment Result: Partial (IUCN, 2020) Justification: Life-cycle cost projections suggest operational savings over grey infrastructure; nevertheless, multi-year funding guarantees and detailed cost-benefit sensitivity analyses are partially defined (Global Center on Adaptation & IUCN Bangladesh, 2025; The Business Standard, 2025). Criterion 5: Inclusive Governance & Equity Stakeholder Engagement: Institutional management led by the Forest Department, integrated with scientific oversight committees, student research networks, public user forums (Bangladesh Forest Department, 2019; Vitti Government Projects Division, 2021). Test Score: 16 / 27 (59%) Assessment Result: Partial (IUCN, 2020) Justification: High participation exists across state entities and research partners, however binding protocols to ensure equitable decision-making and access rights for low-income local community members are partially established (MoEFCC, 2023; The Business Standard, 2025). Criterion 6: Balancing Goals & Impacts Trade-Off Management: Balances public access with the protection of sensitive core conservation zones (Bangladesh Forest Department, 2019; Vitti Government Projects Division, 2021). Test Score: 10 / 15 (67%) Assessment Result: Adequate (IUCN, 2020) Justification: Spatial zoning successfully delineates high density public educational areas from core native conservation zones, minimizing potential trade-offs between public visitation and ecological preservation (Bangladesh Forest Department, 2019; Halder, 2020).

93Criterion 7: Adaptive Management Monitoring Protocols: Real-time water quality monitoring, canopy health tracking via remote sensing, annual biodiversity audits (Global Center on Adaptation & IUCN Bangladesh, 2025; Vitti Government Projects Division, 2021). Test Score: 12 / 18 (67%) Assessment Result: Adequate (IUCN, 2020) Justification: Strategy includes 5-year iterative review cycles, allowing for the site's management to adapt continuously to ecological responses and emerging climate patterns (IUCN, 2020; MoEFCC, 2023). Criterion 8: Enhancing Sustainability and Mainstreaming Policy Scaling: Positioned as a model urban NbS project to guide urban green space restoration across Bangladesh under the National Adaptation Plan (Global Center on Adaptation & IUCN Bangladesh, 2025; MoEFCC, 2023). Test Score: 8 / 15 (53%) Assessment Result: Partial (IUCN, 2020) Justification: Lessons learned from the garden's restoration provides valuable practical models, however, formal legislative pathways to scale this practice across municipal urban planning frameworks are partially developed (IUCN, 2020; MoEFCC, 2023). Strengths, Limitation and Challenges The botanical garden possesses significant advantages, including a large spatial footprint of over 200 acres that provides ample room for functional ecosystems within Dhaka's urban sprawl. It is supported by a reliable institutional foundation through partnerships with the Forest Department and the Bangladesh National Herbarium, which facilitates scientific study. As an iconic natural landmark with high public visibility, the site has the potential to serve as a role model for Nature-based Solutions (NbS) across South Asia's densely populated megapolises. However, the site faces key limitations, including high external boundary pressures from surrounding industrialization and urbanization that generate pollution beyond the project's control. Furthermore, decades of concrete construction have left the soil highly compacted and altered, requiring significant vegetation recovery efforts to restore its natural structure. Executing the NbS initiative presents specific implementation challenges, notably the removal of invasive species. Eliminating matured trees such as Eucalyptus is necessary but can cause temporary canopy loss and disrupt the local ecosystem. Success also depends heavily on inter-agency coordination among the Forest Department, Dhaka North City Corporation (DNCC), the Water Development Board, and local police. These actions carry possible risks and unintended consequences, such as short-term habitat loss where eradicating invasive vegetation may temporarily reduce avian and mammalian diversity before new understory plants emerge. Additionally, upgrading hospitality infrastructure could lead to tourist saturation and congestion if visitation numbers are not strictly regulated on a seasonal basis. The management plan addresses equity and inclusion by proposing subsidized general admission passes for low-income households, ensuring that increasing entry fees do not prevent vulnerable populations from accessing the forest. To balance this, upscale eco-luxury packages will be reserved for paying tourists to support revenue. Furthermore, the construction of pedestrian paths and facilities must adhere to universal design standards to properly accommodate the elderly and persons living with disabilities.

94Trade-Offs Among Environmental, Social, And Economic Objectives Reinstating the forest’s natural cover requires restricting the general public’s access to the conservation zone (Bangladesh Forest Department, 2019; Halder, 2020). To balance nature conservation and public interest, 30% of the NBG will be opened to educational and recreational activities while 70% will be managed as biodiversity conservation, water filtration, and scientific research reserves (IUCN, 2020; Vitti Government Projects Division, 2021). The plan to restore the National Botanical Garden will involve a phased five-year approach to avoid causing significant disruptions to the forest ecosystem while ensuring tourism activities continue (Bangladesh Forest Department, 2019; MoEFCC, 2023). The timeline is structured as follows: Year 1: Terrestrial and Aquatic Eco-systemic Clean-up, Dredging, and Physical Borders Reinforcement. Year 2: Wetland engineering, bioswale installation, and solar-powered water re-circulation. Year 3: Targeted invasive vegetation clearance and native canopy planting. Year 4: Eco-pedestrian path construction and interpretive center development. Year 5: Institutional governance transition and long-term monitoring. Year 1: Site Clean-up, Lake Dredging, and Perimeter Protection To begin the restoration, a perimeter eco shield will be established by planting a mixed-species hedge along the forest’s boundary to act as a noise and particulate barrier (MoEFCC, 2023; Vitti Government Projects Division, 2021). Hydrological restoration will involve clearing silt from the lake bottoms using specialized suction equipment while replacing concrete edges with excavated riverine alluvial soil to recreate natural lake ecosystems (Global Center on Adaptation & IUCN Bangladesh, 2025; The Business Standard, 2025). Additionally, a wetland and forest clean-up will remove accumulated plastics from the aquatic and lowland forest ecosystem, and appropriate floating trash barriers will be installed along the main stormwater entry points (Bangladesh Forest Department, 2019; Chowdhury, 2025). Year 2: Wetland Engineering and Permeable Surface Installation The second phase focuses on constructing a series of interconnected wetlands using excavated soil to improve water filtration and create new habitats for amphibians and waterfowl (Bangladesh Forest Department, 2019; Halder, 2020). Alongside this, specially designed porous pavement will be installed along select trails to prevent surface runoff and soil erosion (IUCN, 2020; Vitti Government Projects Division, 2021). Year 3: Invasive Vegetation Clearance and Native Forest Planting A rotational clearing program will be instituted to remove invasive tree species from 10 forest blocks while maintaining forest cover continuity (Bangladesh Forest Department, 2019; Halder, 2020). These blocks will then be replanted with high-value indigenous timber and fruit tree species such as Madhuca longifolia, Santalum album, Terminalia arjuna, and Dipterocarpus turbinatus (Halder, 2020; MoEFCC, 2023). To complete the ecosystem restoration, the understory will be re-developed by establishing a diverse range of native orchid, fern, shrub, and shade-loving medicinal plant species to reinvigorate the forest’s vegetation (Bangladesh Forest Department, 2019; Chowdhury, 2025). Year 4: Eco-Luxury Resort Construction and Public Interpretation Upgrades During the fourth year, construction of the proposed eco-resort will begin (The Business Standard, 2025; Vitti Government Projects Division, 2021). Eco-educational infrastructure will be developed, including an eco-learning center with solar panel roofing and interpretive signage about the city’s ecology and conservation efforts (MoEFCC, 2023; Vitti Government Projects Division, 2021).

95To engage the public, digitalized QR code plant tags will be produced and affixed to rare and endemic species, allowing visitors to scan and learn about each plant digitally (Bangladesh Forest Department, 2019; Halder, 2020). Finally, elevated bird watching towers and canopy walkways will be built within the public park domain to enable visitors to observe the forest’s biodiversity up close without disturbing sensitive vegetation (Chowdhury, 2025; Vitti Government Projects Division, 2021). Year 5: Governance Transition and Long-Term Forest Monitoring The final phase involves forming an advisory board comprised of the Forest Department, research institutes, municipal authorities, and local community representatives to oversee the governance of the NBG (MoEFCC, 2023; The Business Standard, 2025). A network of environmental sensors will be installed to monitor the forest’s soil moisture, particulate matter, water temperature, and dissolved oxygen levels (Global Center on Adaptation & IUCN Bangladesh, 2025; Vitti Government Projects Division, 2021). To ensure long-term sustainability, a portion of the forest’s tourism and research revenues will be allocated to its ongoing maintenance and conservation needs (Bangladesh Forest Department, 2019; IUCN, 2020). Conclusion The National Botanical Garden currently faces a dire conservation crisis (Bangladesh Forest Department, 2019; The Business Standard, 2025). Encroaching urbanization and environmental stresses have compromised the forest’s natural ecological functions, but a NbS intervention can help repair some of the damage (Global Center on Adaptation & IUCN Bangladesh, 2025; IUCN, 2020). Using a combination of permeable surface structures, man-made wetlands, and replanted forests, the NBG can re-establish its natural ecological integrity (MoEFCC, 2023; Vitti Government Projects Division, 2021). NbS approach fits within the IUCN global standard by providing urban climate adaptation, biodiversity conservation, and public access benefits that justify the investment to restore the NBG (Halder, 2020; IUCN, 2020). Restoring the NBG will produce a flagship conservation project for Bangladesh that will serve as an urban climate adaptation and biodiversity conservation model for the region (Global Center on Adaptation & IUCN Bangladesh, 2025; MoEFCC, 2023)References Anjum, B., Sultana, R., & Saddaf, N. (2024). The effectiveness of nature-based solutions to address climate change in Dhaka, Bangladesh. Social Sciences & Humanities Open, 10(100985), 1–16. https://doi.org/10.1016/j.ssaho.2024.100985 Bangladesh Forest Department. (2019). Management plan and biodiversity assessment for the National Botanical Garden, Mirpur. Ministry of Environment, Forest and Climate Change, Government of the People’s Republic of Bangladesh. Bashar, K., Rain, F. F., Jesmin, M., & Asaduzzaman. (2014). Surveillance of mosquitoes in some selected parks and gardens of Dhaka city, Bangladesh. International Journal of Mosquito Research, 1(2), 5–9. Chowdhury, A. P. (2025, May 12). Bangladesh’s urban wildlife is losing the climate battle. Dhaka Tribune. https://www.dhakatribune.com/opinion/specials/389435/bangladesh%E2%80%99s-urban-wildlife-is-losing- the-climate Global Center on Adaptation, & IUCN Bangladesh. (2025). National compendium on nature-based solutions for urban resilience in Bangladesh. IUCN Urban Alliance. Halder, S. (2020, August 28). National Botanical Garden conserving 226 rare plant species. The Business Standard. https://www.tbsnews.net/environment/national-botanical-garden-conserving-226-rare-plant-species-154786 International Union for Conservation of Nature. (2020). IUCN global standard for nature-based solutions: A user- friendly framework for the verification, design and scaling up of NbS (1st ed.). IUCN. https://doi.org/10.2305/IUCN.CH.2020.08.en

96Ministry of Environment, Forest and Climate Change. (2023). National adaptation plan of Bangladesh (2023–2050). Government of the People’s Republic of Bangladesh. Pasha, A. B. M. K., Chowdhury, A. H., Hussain, A., Rahman, M., Mozumder, S., & Dela Fuente, J. A. (2021). Identification of the ecosystem services and plant diversity in Ramna Park Dhaka. SPR, 1(4), 286–297. The Business Standard. (2025, January 15). The hidden cost of 'development' in the Botanical Garden. The Business Standard. https://www.tbsnews.net/features/panorama/hidden-cost-development-botanical-garden-1154836 Vitti Government Projects Division. (2021). Master plan update and ecosystem conservation with essential infrastructure development of National Botanical Garden, Mirpur, Dhaka. Vitti Architecture & Planning. Bangladesh Forest Department. (2019). Management plan and biodiversity assessment for the National Botanical Garden, Mirpur. Ministry of Environment, Forest and Climate Change, Government of the People’s Republic of Bangladesh. Ministry of Environment, Forest and Climate Change. (2022). Bangladesh national report on biodiversity conservation and ex-situ plant protection. Government of the People’s Republic of Bangladesh. Bangladesh Forest Department. (2019). Management plan and biodiversity assessment for the National Botanical Garden, Mirpur. Ministry of Environment, Forest and Climate Change, Government of the People’s Republic of Bangladesh. Chowdhury, A. P. (2025). Bangladesh’s urban wildlife is losing the climate battle. Dhaka Tribune.https://www.dhakatribune.com/opinion/specials/389435/bangladesh%E2%80%99s-urban-wildlife-is- losing-the-climate

13 Vetiver Grass Bioshields for Riverbank and Slope Stabilization: A Nature-Based Solution Case Study from Chilmari Upazila, Kurigram District, Bangladesh Sadman Tajwar Orko, Md Saminuzzaman Kham, & Tayasshuk Hassan Khan EramAbstract The National Botanical Garden (NBG) of Bangladesh is located in the urban area of Mirpur, Dhaka and covers about 208 acres (84 hectares) of urban ecology landscape. Founded in 1961 as a central sanctuary for ex-situ plant conservation, systematic botanical research, and public education, the NBG has been severely degraded. Rapid, unplanned urbanization in Greater Dhaka, compound climate hazards, thermal anomalies, severe stormwater runoff, atmospheric pollution, and historic eco- engineering missteps have degraded the ecological integrity of the 57 management blocks of NBG.This report presents a structured plan for fixing, restoring and future-proofing the National Botanical Garden using a Nature-based Solution framework in line with the International Union of Conservation of Nature (IUCN) Global Standard for NbS. The proposed intervention replaces grey infrastructure interventions with bio-adapted hydraulic engineering, native canopy reforestation, habitat connectivity corridors and inclusive co-governance models. Through a multi-phase restoration program that has been evaluated against the 8 IUCN NbS criteria, this report details how the NBG can be transformed from a deteriorating green space into a resilient urban ecological anchor that can mitigate disaster risks, sequester urban carbon, cool Mirpur's microclimate and safeguard Bangladesh's plant genetic resources. Keywords: National Botanical Garden Bangladesh; Disaster ManagementDepartment of Disaster Management and Environmental Studies, Brac University, BangladeshIntroduction Bangladesh is the country of rivers where more than two hundred river flows throughout the country. One of the most powerful of them is Brahmaputra-Jamuna. At the far north of the country the Brahmaputra enters from India and Kurigram District sits exactly there resulting to be one of the most erosion hit districts. Here Chilmari Upazila is one of the worst affected areas as it is in the rivers west bank for which its riverbanks, char lands, flood embankments have been getting eaten for decades. The old Chilmari river port is currently under water about 10 kilometers from where it was (Dhaka Tribune, 2013). Here in Chilmari yearly monsoon floods, constant shifting channels and carried sediments from the Himalayas makes erosions worse (Ittefaq, 2026). Riverbank erosion is a major crisis in Bangladesh which annually destroys approximately 10,000 hectares of land directly affecting over 100,000 individuals (The Daily Star,2026a). In Kurigran a 70- kilometer corridor covering Nageshwari, Kurigram Sadar, Ulipur, Chilmari, Roumari and Char Rajibpur has suffered erosion continuously since 1950.97

98Annually receding approximately 50 meters (Ittefaq, 2026). In Chilmari's Raniganj union families lost homes, farmland and orchards within four to five years. Recent monsoon floods destroyed concrete embankments, necessitating critical sandbag stabilization efforts (The Daily Star, 2026b). Standard interventions typically rely on hard engineering such as concrete blocks, sandbags and stone walls. Although these solutions are expensive, machinery dependent and prone to sudden failure on the erratic Brahmaputra (Islam et al., 2013). Alternatively, this paper evaluates a cost effective and nature-based solution trialed in Kurigram: planting vetiver grass (Chrysopogon zizanioides) also known as binna ghash as a protective living "bio shield" to defend riverbanks, charland and embankments. This paper examines Chilmari’s acute erosion, how vetiver grass functions as a Nature-based Solution (NbS) supporting evidence of its effectiveness and its alignment with the IUCN Global Standard Self-Assessment Tool. Ultimately evaluating whether vetiver bioshields offer a practical, scalable response for Chilmari where continuous erosion collides with scarce financial resources for heavy concrete infrastructure.Background and Context Chilmari Upazila located in Kurigram District within Rangpur Division covers roughly 225 square kilometres housing approximately 132,000 inhabitants (Wikipedia, n.d.). Its landscape mostly features river channels, seasonal chars and low-lying agricultural land. Brahmaputra is a braided river continuously shifting its channels which destabilizes the riverbanks. According to water expert Ainun Nishat, the erosion reflects the natural traits of a young & active river system but it is getting severely influenced by human activity and interactions (Dhaka Tribune, 2013). The Major Disaster, Climate and Environmental Challenge Life in Chilmari is dependent on two twin hazards annual monsoon flooding and restless riverbank erosion. Intense upstream flows and heavy rainfall continuously pushes Brahmaputra, Dharla, and Teesta past its danger thresholds ultimately swallowing the low-lying chars for weeks and making it hard to communicate to school, clinics and roads (Dhaka Tribune, 2020, 2022). During monsoon months erosion is a daily occurrence inflicting deeper long-term damage (Dhaka Tribune, 2013). Climate change elaborates these vulnerabilities by fortifying mountain runoff and shifting seasonal rainfall distribution (Ittefaq, 2026). Rural families by riverbanks and char lands primarily rely on farming, fishing and daily labor faces the greatest risks. When erosion happens it succumbs homes, farmland, orchards and community infrastructure greatly impacting the poorest the hardest due to restriction to mobility (Dhaka Tribune, 2020). In Chilmari's Raniganj union, families split and social ties get erased as the natives’ scatter for living or surviving (The Daily Star, 2026a). Compounding this loose, sandy, flood prone soils prevent the survival of plants. Which makes riverbanks barren, exposed in a word vulnerable against the going erosion. Char land is deeply linked with Chikmari’s continuous erosion. These sand bags rapidly reclaimed when the altered currents push them away. Despite losing them the natives continuously resettle these temporary chars because of the lack of alternative land. Rather than the static riverbank regions Chilmari shows constant spatial relocation of land and water. For coastal protections to be effective here it has to adapt to all these diverse channel mitigation, sudden formation changes and everything. Traditional bank protection stays excessively costly demonstrated by BWDB's 850 crore taka proposal for Kurigram (Ittefaq, 2026). Following concrete's high expense and high failure rates the multi donor LoGIC project engaged BUET to determine vetiver-based bioengineering (UNDP, n.d.). As a result, BUET selected Kurigram's eroding banks as one of three national test sites next to Khulna and Sunamganj (Islam et al., 2021). This research supplies the primary technical evidence analyzed here placing Chilmari within a broader national campaign testing vetiver as a viable Nature based Solution (NbS).

99Description of the Nature-Based Solution Vetiver grass is South Asian perennial which is noninvasive, fast growing with vertically extending roots two to four meters downwards (Islam et al., 2008; The Business Standard, 2024). These are planted in dense rows by the riverbanks thus the connected roots reinforce the soil as like steel rebar strengthens concrete making it more resistant (Islam et al., 2013). And above ground the thick hedges reduce surface runoff velocity, trap sediments and attenuate wave impact. While deep roots fortify the ground from water invasion which reduces surface scouring (Islam et al., 2021). To evaluate vetiver bioengineering across distinct environment Under the LoGIC project, BUET researchers conducted a pilot in Kurigram (Islam et al., 2021). Traditional hard engineering methods which are actually expensive frequently fail in Bangladesh's flood conditions resulting sites like Chilmari unprotected (Islam et al., 2013). Here comes vetiver as a practical alternative which is easy and affordable to cultivate, no need for heavy equipment and also encourages the locals to do the cultivation themselves. The residents who reside near the river or char are the most benefited as their homes and living are vulnerable to the risk along with under construction sites, roads and embankments. Beside this vetiver creates an income source for the rural women through nursery propagation and harvesting stems for thatch, fodder or crafts (Islam et al., 2008). Planted along with loose Brahmaputra riverbanks, floodplains and embankment slopes, vetiver anchors the bare ground. It enables other native species to take root as well which enhances long term ecological degraded riparian zones. Beyond its erosion resilience, vetiver possesses vital traits for Chilmari’s dynamic climate. It can withstand both droughts and partial flood intrusion navigating the region's seasonal extremes (The Business Standard, 2024). It's capable of thriving in poor, sandy soils unsuitable for agriculture and also avoids competing with crops. Because it propagates vegetatively it forms dense, non-invasive clumps (Islam et al., 2008). These ecological attributes of it makes it different from other species and makes it as the preferred species for bioengineering. Vetiver fights against erosion is three distinct mechanisms; Firstly, to prevent structural slumping, deep root networks anchor fragile soil. Secondly, dense foliage buffers direct to dissipate wave energy, rainfall, and current forces. Thirdly, root channels ground infiltration decreases erosive surface runoff (Islam et al., 2021). Moreover, as a living organism it possesses self-regenerative capacity recovering from partial burial or minor damage. As a result, it offers a persistent dynamic protection not like the rigid engineered structures which are frail upon cracking down. Evidence and Impacts Empirical studies in Bangladesh offer a strong technical proof of vetiver's protective capacity. It is seen in the Geotechnical tests that out binding significantly increases shear strength in both cohesive and sandy soils, directly enhancing slope stability (Islam et al., 2013). It is revealed in the simulated rainfall experiment that agitated slopes reduced runoff by 18 to 71 percent compared to bare earth (Islam et al., 2021). Additionally, geotextile-reinforced vetiver trials under wave action showed extreme durability and minimal soil loss related to untreated embankments (Islam et al., 2013). These principles apply directly to the Brahmaputra’s sandy riverbanks. This particular use of vetivar is not only conducted in Bangladesh but we can see similar programs in Vietnam, the Philippines, China and India coming with a positive esults for controlling erosion on riverbanks and slopes (Mondal & Patel, 2020). In West Bengal it came to be seen that vetiver significantly lowered annual repair costs and protected agricultural land far cheaper than concrete interventions (Mondal & Patel, 2020). As we both share similar river systems, soil and climate with the northern Bangladesh these outcomes highly suggest vetiver can succeed in Chilmari despite limited site-specific data.

100Because vetiver is locally cultivated and manually planted it enables direct community participation through local nursery cultivation and non-specialized planting. Proofs from a similar project in West Bengal underscores community buy in and government support as key drivers of success (Mondal & Patel, 2020). On top of that it produces revenue and raw materials for roofing, livestock feed and handicrafts (Islam et al., 2008). Vetiver’s single greatest advantage is its affordability. Unlike concrete blocks, stone walls or sandbags which require manufactured inputs, heavy equipment, and external contractors, vetiver is cultivated locally and planted manually (Islam et al., 2013). Vetiver is grown locally and planted by hand retaining project expenditures within the community as wages. Kurigram’s proposed 850-crore-taka structural initiative demonstrates the steep price of hard engineering (Ittefaq, 2026), low-cost nature-based options become vital for securing unprotected riverbank stretches. As it slows down erosion vetiver helps to extend the life of nearby embankments, roads, and homes, severe losses already seen in Chilmari's Raniganj union (The Daily Star, 2026a). As it also reduces runoff it may help lower the risk of local flash flooding on slopes and embankments during heavy rain (Islam et al., 2021). As it is a living organism, vetiver should become more effective over time as its roots grow deeper, as long as the plants survive their first year and are not overwhelmed by extreme floods. For vetiver planted specifically on Kurigram's riverbanks there is not much long-term, real-world data available. Most of the strong evidence are of root strength and runoff reduction figures, comes from BUET's lab and model tests rather than years of field monitoring at the actual pilot site. This is an important gap and it shows a clear need for ongoing field checks; such as tracking plant survival, measuring bank movement and comparing costs over several flood seasons. So that before vetiver use in Chilmari can be fully confirmed and expanded with confidence. IUCN NbS Self-Assessment The IUCN Global Standard for Nature-based Solutions Self-Assessment Tool checks a project against eight criteria: societal challenges, design at scale, biodiversity gain, economic viability, governance, trade-offs, adaptive management, and mainstreaming (IUCN, 2020).

101Based on the evidence gathered above, the vetiver bioshield idea for Chilmari is assessed below. Since this paper is based on published research rather than a live project visit, these are estimated scores. Vetiver scores strongly on Criterion 1 (societal challenge) and Criterion 4 (economic viability). The erosion problem it addresses is severe and well proven, and its low cost compared with concrete is supported across the research. This combination makes vetiver attractive for a place like Chilmari, where the 850-crore-taka structural project cannot realistically reach every vulnerable stretch of riverbank. The weakest areas are Criterion 3 (biodiversity gain) and Criterion 7 (adaptive management). Most current research looks at vetiver only as an engineering tool, checking soil strength and water runoff, but rarely follows ecological results like new plants or animals, or how well the grass survives over time at the Kurigram site. Governance and trade-offs (Criteria 5 and 6) have some support because project-level information is available through LoGIC, but detailed, site-level data from Chilmari was not found. Vetiver bioshields in Chilmari represent a promising well-tested pilot rather than a fully verified, long-term solution. Although technical and financial evidence is compelling, documentation surrounding local governance, ecological outcomes and long-term upkeep is lacking. This imbalance often affects engineering led Nature based Solutions. Establishing systemic monitoring, recording community governance models and measuring biodiversity impact would surely boost Chilmari’s score under the IUCN Global Standard.

102Strengths, Limitations and Challenges Vetiver bioshields have a clear advantage for Chilmari as they cost far less to build and maintain than the sandbags and it also needs no machinery. It can be planted using local labour(Islam et al., 2013). As it is alive, it keeps growing and also able to repair itself. Side benefits like income from selling fresh plants is also one of its traits. It can be added gradually along risky areas without needing a huge budget upfront (Islam et al., 2008; Ittefaq, 2026). Vetiver only works well once its roots are established, so young plants can be washed away if strong floods arrive too soon after planting. The Brahmaputra at Chilmari is a very powerful, fast-changing river, and at the worst erosion spots, the force of the water may be too strong for grass roots alone to handle, meaning vetiver works best alongside concrete protection rather than replacing it completely at the most critical points (Dhaka Tribune, 2013). Much of the supporting data also comes from lab tests rather than years of real-world testing on Kurigram's riverbanks, so its long-term performance there is less certain than the lab results suggest. Practical problems include growing enough young plants to cover a seventy kilometre stretch of riverbank, timing planting around the river's rise and fall each year and protecting new plants from being grazed, trampled or cut for fuel before their roots mature. Long-term success also needs ongoing support from local government or the community. Which can be harder to keep going once a funded project like LoGIC ends. Rather than making a one large planning method for bringing vetiver to scale in Chilmari it would need a phased plan to be executed better. First phase focusing on lower risk, calmer stretches of char land and embankment to build local nursery capacity and train community members in planting and caring it. Once its nicely established and the survival is confirmed planting could expand to cover more of the seventy- kilometre erosion zone. This approach will also make it easier to monitor results such as what adjustments should be taken based on planting methods and restrain from wasting resources on areas where the river's force is too strong for grass roots to hold. It would also give local government time to secure a steady source of planting material instead of relying on donor funding that may end when a project like LoGIC concludes. Unintended Consequences If not managed well, vetiver plantings could give people false confidence in areas where the river is simply too strong for grass to hold back, possibly delaying more urgent concrete work at the most dangerous spots. There is also a risk that poor households might cut down young vetiver too early for fuel or roofing material, before its roots are strong enough to protect the soil. Since vetiver has created income for women elsewhere in Bangladesh, care should be taken to make sure these benefits reach poorer and female-headed households fairly, rather than being taken mostly by better- connected families (Islam et al., 2008). The families most affected by erosion, especially those living on char land, are often the poorest and most likely to move away, so they may have the least chance to stay involved in caring for vetiver plants long enough for the roots to mature. Trade-offs between Environmental, Social, and Economic Objectives Decision makers witness a clear trade off involving how affordable and easy to install vetiver is against concrete's superior reliability at severe erosion points. But only relying on vetiver exposes high risk zones where the current is severe. And funding only on concrete leaves most vulnerable areas unprotected due to budget limitation. A joint step of vetiver along longer, calmer stretches. And reserving concrete for critical locations offers the most balanced economic, social and environmental solution.

103Conclusion This paper looked at vetiver grass bio shields as a nature-based solution for riverbank erosion in Chilmari Upazila, Kurigram District, an area badly affected by Brahmaputra riverbank erosion and yearly flooding. The evidence shows that vetiver's deep root system clearly improves soil strength and reduces runoff and erosion in Bangladeshi soil conditions, and that it has already been tested specifically on a riverbank site in Kurigram through the government-led, UNDP- and UNCDF-supported LoGIC project with BUET. Compared with concrete, stone, or sandbag protection, vetiver is much cheaper, easier for local government to use, and offers useful income side benefits, making it a realistic response to a problem whose scale, about fifty meters of bank lost every year along a seventy-kilometer stretch, is too large for one costly structural project to solve everywhere. Meanwhile checking vetiver against the IUCN Global Standard shows that its evidence base is not stable in a word not even. It has a high score on addressing a real problem and on cost efficiency. But the score is poor on biodiversity, community governance and, most importantly, long-term monitoring specific to Chilmari. Finally, this is a technically promising but only partly proven solution. Good enough to justify wider use but still needs better field monitoring and clearer community involvement to fully meet the Global Standard. Vetiver bio shields function best not as absolute replacements for concrete at high-risk hotspots but as a scalable, cost-effective option for extended char lands, embankments and moderate riverbank zones. Broadening plantation coverage, settling strict monitoring or plant survival and migration of channel. Tracking community benefits will refine technical outcomes also elevates the projects Global Standard rating. Which will ultimately pave the way for larger implementation throughout Kurigram and similar flood prone districts.Reference Dhaka Tribune. (2013, October 19). Historic Chilmari port disappears. https://www.dhakatribune.com/bangladesh/bangladesh-others/41068/historic-chilmari-port-disappears Dhaka Tribune. (2020, September 20). Displaced by river erosion, Kurigram locals await rehabilitation. https://www.dhakatribune.com/bangladesh/nation/223722/displaced-by-river-erosion-kurigram-locals-await Dhaka Tribune. (2022, June 18). Flood situation worsens in Kurigram and other dists. https://www.dhakatribune.com/bangladesh/nation/289612/flood-situation-worsens-in-kurigram-and-other International Union for Conservation of Nature. (2020). IUCN Global Standard for Nature-based Solutions: A user-friendly framework for the verification, design and scaling up of NbS (1st ed.). https://portals.iucn.org/library/sites/library/files/documents/2020-020-En.pdf International Union for Conservation of Nature. (n.d.). IUCN Global Standard for Nature-based Solutions Self- Assessment Tool. Retrieved August 30, 2026, from https://inbs.iucn.org/apply/nature-based-solutions- self-assessment/tool/ Islam, M. P., Bhuiyan, M. K. H., & Hossain, M. Z. (2008). Vetiver grass as a potential resource for rural development in Bangladesh. Agricultural Engineering International: The CIGR Ejournal, 10. Islam, M. S., Arifuzzaman, M. D., Shahin, H., & Nasrin, S. (2013). Effectiveness of vetiver root in embankment slope protection: Bangladesh perspective. International Journal of Geotechnical Engineering, 7(2), 136-148. Islam, M. A., Islam, M. S., Chowdhury, M. E., & Badhon, F. F. (2021). Influence of vetiver grass (Chrysopogon zizanioides) on infiltration and erosion control of hill slopes under simulated extreme rainfall condition in Bangladesh. Arabian Journal of Geosciences, 14(2), Article 119. https://doi.org/10.1007/s12517-020-06338-y Ittefaq. (2026, March 27). Kurigram battles climate-driven river erosion; Tk 850cr project awaits nod. https://en.ittefaq.com.bd/15886/kurigram-battles-climate-driven-river-erosion-tk Mondal, S., & Patel, P. P. (2020). Implementing vetiver grass-based riverbank protection programmes in rural West Bengal, India. Natural Hazards, 103(1), 1051-1076. https://doi.org/10.1007/s11069-020-04025-5 The Business Standard. (2024, November 9). Vetiver and bioengineering: A potential solution to develo climate- resilient Bangladesh. https://www.tbsnews.net/thoughts/vetiver-and-bioengineering-potential-solution- develop-climate-resilient-bangladesh-988706

104The Daily Star. (2026a). The river took her land. It also took her name. https://www.thedailystar.net/news/environment/news/the-river-took-her-land-it-also-took-her-name-4239031 The Daily Star. (2026b). Brahmaputra embankment collapse puts Chilmari at risk. https://www.thedailystar.net/news/environment/news/brahmaputra-embankment-collapse-puts-chilmari-risk- 4226071 United Nations Development Programme. (n.d.). Local Government Initiatives on Climate Change (LoGIC). Retrieved August 30, 2026, from https://www.undp.org/bangladesh/projects/local-government-initiatives-climate-change-logic

14 Case study of Nikli Haor as a viable Nature Based Solution (NbS) Yusha Al Washfi & Arif MustakimAbstract The National Botanical Garden (NBG) of Bangladesh is located in the urban area of Mirpur, Dhaka and covers about 208 acres (84 hectares) of urban ecology landscape. Founded in 1961 as a central sanctuary for ex-situ plant conservation, systematic botanical research, and public education, the NBG has been severely degraded. Rapid, unplanned urbanization in Greater Dhaka, compound climate hazards, thermal anomalies, severe stormwater runoff, atmospheric pollution, and historic eco- engineering missteps have degraded the ecological integrity of the 57 management blocks of NBG.This report presents a structured plan for fixing, restoring and future-proofing the National Botanical Garden using a Nature-based Solution framework in line with the International Union of Conservation of Nature (IUCN) Global Standard for NbS. The proposed intervention replaces grey infrastructure interventions with bio-adapted hydraulic engineering, native canopy reforestation, habitat connectivity corridors and inclusive co-governance models. Through a multi-phase restoration program that has been evaluated against the 8 IUCN NbS criteria, this report details how the NBG can be transformed from a deteriorating green space into a resilient urban ecological anchor that can mitigate disaster risks, sequester urban carbon, cool Mirpur's microclimate and safeguard Bangladesh's plant genetic resources. Keywords: National Botanical Garden Bangladesh; Disaster ManagementDepartment of Disaster Management and Environmental Studies, Brac University, BangladeshIntroduction Nikli Haor is one of the largest Wetland ecosystems in Bangladesh. Which is situated in Sunamganj, Nikli upazilla, Kishoreganj district. It is known for its natural beauty which is mainly covered with water bodies and the roads that leads the path through the entire haor and they’re all more or less interconnected with each other. The area of nikli haor is more or less 215 sq km. This project was initially taken by our Honorable former president Abdul Hamid. Although he only helps to construct the roads but that brings a great impact and result to convert the isolated haor into a tourism spot. There are some challenges such as, natural flooding, climate change, habitat loss etc. The selected Nature Base Solution is Wetland restoration and conservation. It also includes maintaining water bodies and restoring it habitats and using its land mass to reduce flood vulnerability. This steps/ approach can minimize the impact of flood while maintaining its natural habitat and biodiversity. This assignment is to observe how wetland-based Nature Based Solution (NBS) can marks the environmental and climate related challenges of Nikli Haor and how can we contribute in it. As in today’s climate changing days we have to take a close look or observation in our natural ecosystem and environment like how they react, response with the ongoing climate change. As we are the ones who are disrupting with our natural phenomena. Now it’s the high time to perform our duty accordingly.105

106Background And Context Nikli Haor is located in Nikli Upazila, Kishoreganj, within the Sunamganj region, and covers approximately 214 to 215 square kilometres. It is a seasonally flooded wetland: during the monsoon, large volumes of water become trapped in the enclosed area, creating an inland water body, while in the dry season the water recedes and exposes vast agricultural land. Agricultural land, settlements, and roads are interconnected, and roughly 150,000 local people depend heavily on this water body, with water transportation serving as a primary mode of communication. Famous spots include Itna, Mithamain, Zero Point, and Nikli Beribad. The haor supports a huge aquatic habitat and a substantial economic cycle, helping meet Bangladesh's fish supply demand, moderating local temperatures, and, because of its punctured structure, keeping surrounding lands safe from flooding. However, it faces serious environmental challenges. Nikli Upazila often experiences flash floods and monsoonal flooding, which destroy large numbers of crops, while bank erosion from continuous water currents damages roads and causes settlement collapse. Water pollution is also a growing concern, as unfit vessels used for transport and tourism often leak petroleum, endangering the aquatic habitat. The community consists mainly of farmers, fishermen, and local households, with tourism recently adding a new group; farmers are vulnerable to monsoon crop losses, fishermen face a half-year dry period when the water body dries up, and local households contend with poverty, flooding, settlement erosion, and extreme mental stress documented in Research Gate studies. A mixed ecosystem, in which a farmer could also work as a fisherman, would allow people to benefit from the haor year-round. A Dhaka University study found that the aquatic habitat, water quality, and microbes of haors in Kishoreganj are passing through a meso-eutrophic status, a transitional phase between moderate and high nutrient levels, indicating higher fish productivity potential that could generate revenue and improve livelihoods, though sediment intrusion poses a future risk. According to Banglajol, the water of Nikli Haor is suitable for fish cultivation and supports an income cycle for approximately 1.5 lakh people, and the haor manages water drainage through interconnected canals, functioning as a sewage system for the local community and serving as a good nature-based solution. Description of Nature Based Solution (NBS) According to the International Union for Conservation of Nature (IUCN), Nature-based Solutions (NbS) are actions to protect, sustainably manage, and restore natural or modified ecosystems that address societal challenges effectively and adaptively, simultaneously providing human well-being and biodiversity benefits. NbS are a powerful way to address challenges such as climate change, biodiversity loss, and food security, securing food safety, managing biodiversity balance, and protecting nature while engaging with our day-to-day life. The Global Standard for Nature-based Solutions was developed through public consultation with over 800 practitioners and experts from more than 100 countries, resulting in a robust framework of 8 criteria with 27 associated indicators and guiding questions that help users assess and improve their solutions. Until now, there has been no agreed framework or standard as to what constitutes an effective NbS, and misunderstanding and misuse have led to applications that cause harm to biodiversity and communities and threaten to erode stakeholders' trust in the approach. The IUCN Global Standard is therefore a tool to help governments, communities, businesses, and NGOs implement strong, effective NbS projects that are ambitious in scale and sustainable, preventing misuse and safeguarding people and planet. According to IUCN, NbS are not tied to a single geographical location but are instead applied within nature or mixed ecosystems such as wetlands, forests, coastal zones, man-made lakes, and grasslands, involving multiple ranges of ecosystem rather than a single one, which may also include coastal zones, forests, lakes, and canals either natural or man-made.

107NbS have solved many problems, such as restoring forests to reduce global carbon dioxide emissions and helping reduce global warming by maintaining moisture in the air, showing that NbS is now not only a single target-based solution but a multi-conventional based solution that helps prevent conventional vulnerabilities, and the future of Nature-based Solutions is wider and farther. Nikli Haor is a freshwater wetland ecosystem with significant ecological value. It acts as a habitat for aquatic life and provides an interlinked food web with plankton, fishes, and aquatic vegetation, so the ecological status of Nikli Haor has a direct impact on biodiversity and livelihoods in the area. Recent research provides scientific evidence about the biological significance of Nikli Haor. According to a 2026 study by researchers from the Bangladesh Fisheries Research Institute, which sampled the haor during June 2022 to July 2023, there were 53 species of fish belonging to 20 families and eight orders, but 35.84% of fish species were under threat at various levels, with 11.32% vulnerable, 18.87% endangered, and 5.66% critically endangered, and a declining fish population was also reported. This data proves both the significance and fragility of Nikli Haor: the high number of fish species shows biological value, but the proportion of threatened species reveals the necessity for protection and sustainable management, and preserving fish habitat and natural processes in the wetland could serve to conserve biodiversity while supporting the communities who depend on fishing. Water quality is another indicator of ecosystem health. In 2025, a study in the Dhaka University Journal of Biological Sciences analyzed the water quality and plankton community of Nikli Haor, detecting 42 species of plankton and focusing on physicochemical conditions and plankton community because they are closely related to the food chain of aquatic life and fisheries productivity. According to the results, biological and nutritional parameters of the water show meso-to-eutrophic conditions. These data are important for NbS assessment because a wetland will not be able to provide sustainable ecosystem services if its ecological state continues to deteriorate. Nikli Haor is not just an ecological system but also a livelihood system, as communities rely on fishing, agriculture, transportation, tourism, and other wetland-related activities, making the connection between ecosystem integrity and socio-economic state especially strong. Fishing is one of the main activities related to the haor, and the fisheries study highlights the wetland's role as a place of rich fishing and earning for people who live from fishing, yet the reduction of fish population directly threatens the economy of communities that depend on it. One of the most compelling reasons for treating Nikli Haor as an NbS is the link between the haor and water. In contrast to conventional infrastructural approaches that seek to control water, the wetland system adjusts naturally to water movements, an aspect even more pertinent in Bangladesh where haor communities face flood threats. Research conducted in the Nikli region highlights the vulnerability of housing and livelihood in flood- prone areas, so preserving the ability of the haor to hold and transport water during the season could enhance climate resilience. This, however, does not imply that the wetland itself would resolve flooding issues; instead, it should be done in conjunction with proper infrastructure and early warning systems. IUCN NbS Self‑Assessment The IUCN Global Standard offers eight criteria to evaluate Nature-based Solutions, examining problems, ecological health, economic soundness, governance, trade-offs, adaptive management, and long-term sustainability. The IUCN self-assessment tool lets users compare their project with these criteria and spot strengths and gaps. Importantly, IUCN does not run or certify the self-assessment; the score is a self-ranking that relies on evidence and justification the user supplies. For this paper, the IUCN framework is used as a self-assessment of Nikli Haor, and the assessment does not give an IUCN score.

108Under Criterion 1, effectively addresses challenges, the wetland is rated strong because it helps with flood control, livelihoods, fisheries, recreation, and climate resilience for the community. Criterion 2, design informed by scale, is rated moderate to strong, since the haor works beyond borders and landscape-level planning is needed to keep it effective. Criterion 3, biodiversity net gain, is moderate: the haor has fish species, but 35.84% of the recorded species are at some level of risk. Criterion 4, viability, is strong, as fisheries, farming, and tourism provide jobs and money for residents. Criterion 5, inclusive, transparent, and empowering governance, is moderate, because local people rely on the ecosystem and stronger community participation in decisions is required. Criterion 6, equitably balances trade-offs, is moderate, since fisheries, agriculture, tourism, and conservation often compete for resources. Criterion 7, managed based on evidence, is moderate: recent research offers data, yet ongoing monitoring and flexible management must be improved. Criterion 8, sustainable and mainstreamed, is moderate, as Nikli has long-term prospects but better integration into wetland, climate, and development plans is needed. Based on this assessment, Nikli Haor can be described as having "Partial Adherence with High NbS Potential." This conclusion shows the difference between the system itself and a well-managed Nature-based Solution: the mere presence of a wetland does not automatically make it a Nature-based Solution, and according to the IUCN approach, protection, restoration, or sustainable use must link to needs while benefiting biodiversity and people. Benefits of Nikli Haor as a Nature-based Solution The first benefit of Nikli Haor lies in its multifunctional role. One ecosystem is able to help in biodiversity preservation, fishery, water retention and providing people with their livelihood and recreation. It is the key benefit of Nature-based Solutions as one ecosystem is able to resolve several related issues of society. The second benefit is high value of biodiversity of the ecosystem. The presence of 53 different species of fish is the proof of ecological value of the wetland. Moreover, the vulnerability of many species shows the reason why conservation of the Haor may have such great benefits for biodiversity. Third, the wetland is the basis of livelihoods of the people. Both fishery and agriculture are directly related to socioeconomic situation and tourism adds more options. Fourth, Nikli Haor has good potential for climate resilience. Preserving natural processes in wetland may contribute to accommodation of water in seasons and decrease vulnerability due to total dependence on hard infrastructure. The fifth point is that Nikli Haor already has scientific evidence base. There are some recent studies on fish biodiversity and water quality that can be used for future management and conservation of the ecosystem. Challenges and Limitations Several challenges make it impossible to recognize Nikli Haor as a complete NbS success story. Biodiversity loss is one of the biggest, represented by the decline in fish populations: the 2026 study's finding that 35.84% of fish species are threatened with varying degrees of vulnerability suggests the ecosystem is under biodiversity pressure. Water quality is another challenge, as the determination of meso-to-eutrophic status shows the waterbody requires constant monitoring; poor water conditions may negatively affect biodiversity and fisheries, and while the wetland serves natural water management purposes, surrounding communities still face risks of floods and livelihood losses, with climate change potentially adding further uncertainty and severity to these risks. Tourism pressure is also significant: tourism can bring economic gains to local people, but uncontrolled tourism could lead to pollution, noise, and habitat disturbance, so tourism must be limited to the carrying capacity of the wetland ecosystem. Governance and conflicts among stakeholders remain a concern, and the lack of long-term monitoring is a further gap: while recent research brings important findings, implementing NbS requires monitoring, evaluation, and adaptation to changing circumstances, and according to the IUCN framework, learning is the key rather than just conducting a single assessment.

109Recommendations To improve the capacity of Nikli Haor as an NbS, several steps need to be taken. First, community-based wetland governance must be improved, with fishers, farmers, tour agencies, local communities, and even the government involved in decision-making. Second, breeding sites for fish should be conserved, and the establishment of seasonal protected areas and fishing restrictions during breeding periods may help restore threatened fish populations. Third, routine water quality monitoring should be done, consisting of measurements of dissolved oxygen, nutrients, pH, and other parameters. Fourth, tourism should be based on the principle of ecotourism, with the establishment of waste-management systems, boat trails, and other measures to reduce negative ecological impacts. Fifth, long-term monitoring of biodiversity should consider fish, plankton, aquatic vegetation, and other components of the ecosystem. Finally, Nikli Haor should become part of climate change adaptation, fisheries management, biodiversity management, and wetland management policies, which will allow better utilization of the ecosystem. Conclusion The case study shows the great potential of wetlands to act as NbS in Bangladesh. Ecological roles include fish diversity, water regulation, and aquatic food webs, while socioeconomic functions include fisheries, agriculture, tourism, and local livelihoods, and recent research gives strong evidence for its ecological significance in terms of 53 fish species and 42 plankton taxa. At the same time, the evidence shows the ecosystem's vulnerability: the threatened status of 35.84% of fish species recorded in Nikli Haor, reduction of fish abundance and diversity, problems with water quality, floods, and the increase of human activities show that the ecosystem cannot be regarded as ecologically healthy. The self- evaluation of the site according to the IUCN criteria shows that it can be evaluated as Partial Adherence with High NbS Potential: Nikli Haor has many advantages in terms of addressing societal challenges and providing benefits, but requires better governance, biodiversity protection, adaptive management, monitoring, and long-term planning. It is especially crucial to note that Nikli Haor cannot be regarded as a Nature-based Solution simply because it is a natural site; however, if its natural functions are preserved and managed in a sustainable manner to solve flooding, climate, and other problems, then Nikli Haor can be regarded as an NbS. The future of Nikli Haor depends on the proper balance between conservation and development, people's livelihood and biodiversity, and tourism and ecology. If these interests are balanced through community involvement, scientific monitoring, and adaptive management, then Nikli Haor can be not only a valuable wetland ecosystem but a practical case of climate resilience and biodiversity protection in Bangladesh. References International Union for Conservation of Nature (IUCN). (2020). IUCN Global Standard for Nature-based Solutions: A user-friendly framework for the verification, design and scaling up of NbS. Gland, Switzerland: IUCN IUCN Global Standard for Nature-based Solutions. International Union for Conservation of Nature (IUCN). IUCN Global Standard for Nature-based Solutions. Nahiduzzaman, M., Karim, E., Nisheeth, N. N., Alam, M. S., Al-Amin, Rashid, M. H., & Bhadra, A. (2026). Fish Biodiversity at Nikli Haor of Northeastern Bangladesh: Fish abundance, Composition and Conservation Status. Bangladesh Journal of Fisheries Research, 1(2), 59–75. Rahman, A., Nahin, M., Saykot, S. H., Uddin, M. L., Khondker, M., & Bhuiyan, M. A. H. (2025). Assessment of water quality and plankton composition of Nikli Haor, Kishoreganj, Bangladesh. Dhaka University Journal of Biological Sciences, 34(2), 89–101. Housing in the Haors: Adapting to Flood Prone Landscapes of NorthEastern Bangladesh. (2025). International Journal of Environmental Sciences, 11(20s), 3371–3395.

Message from Key Personal

Disaster Education at Brac UniversityFuad Hassan Mallick, PhD Professor and Dean, School of Architecture and Design Acting Chairperson, Department of Disaster Management and Environmental Studies BRAC UniversityThat Bangladesh should have academic programs in Disaster Management, is quite obvious. The country has long been a disaster-prone country. In instances of the past, like the Bhola cyclone of 1970 and others, Bangladesh was caught off guard and unprepared. In later years disaster management improved significantly. By the early 2000’s Bangladesh was making a name for itself in disaster management and preparedness. Why not then a formal academic engagement. Professor Jamilur Reza Choudhury, himself a name as a leading academic and expert on disasters, having been the team leader in the Multi-Purpose Cyclone Shelter Project (MPCSP) and an authority on earthquakes was the first Vice Chancellor of Brac University. He initiated the Post Graduate Programs in Disaster Management (PPDM) at the university in early 2003. For reasons best known to himself, he asked me to start the program along with leading the Department of Architecture. The PPDM was launched in 2005, after Dr. Iftekhar Ahmed had prepared the curriculum. It was the first formal course of studies in the discipline in the of whole south east/ south Asia region. In hindsight, Prof. Choudhury, had made the right decision for the program thrived. In its 20 plus years of its existence PPDM has progressed from a small teaching unit into a repository of knowledge and information. It has been able to connect with organizations locally and internationally. Our alumni are now well placed in different organizations. The network of students and teachers is extensive and offers exciting opportunities. When it started PPDM concentrated mainly on natural disasters, with time the scope has extended to other types of disasters and hazards and the repertoire of its activities and research, has a wide spectrum now. With the reach of the subject extending further, PPDM is keeping pace. The scope of Disaster Management as an interdisciplinary topic has increased significantly in the last few years. It is now at the intersection of a wide range of subjects. The sciences, the social sciences, technology, planning, architecture etc. As the reach increases, PPDM embraces all. As it stands at the crossroads, disaster education will have to combine practice and theory, to strengthen itself. While there are countless examples of practice, they need to be further placed in a theoretical framework, increasing the robustness of the discipline. The PPDM is just doing that. Gathering it 20 plus years of experience and the wealth of information it has, it is on its way to be a leading discipline, and like its inception at Brac University, where else?149

The Journey of PPDMIftekhar Ahmed, PhD Associate Professor School of Architecture and Built Environment University of Newcastle, AustraliaThe idea of the Postgraduate Programs in Disaster Management (PPDM) at BRAC University was initiated in 2003 during the Earthquake Vulnerability Reduction in Cities (EVRC) training course organized jointly by Brac University and the Asian Disaster Preparedness Center (ADPC) in Rajendrapur, Bangladesh. PPDM was proposed by Prof J R Choudhury, Vice Chancellor of BRAC University at that time and was met with a pledge of scholarship support from Mr Sanwar Ali of Oxfam-BD. At that time, I was an Associate Professor at the Bangladesh University of Engineering & Technology (BUET), and I was appointed as a consultant for the curriculum development of the program. Extensive feedback was received from various groups and individuals during the curriculum development stage, particularly from the Disaster Risk Reduction Group (DRRG), a network of individuals working in disaster management-related roles in various organizations in Bangladesh including the Bangladesh Disaster Preparedness Center (BDPC), Care-Bangladesh, Oxfam-BD, UNDP and Jahangirnager University. After successive review stages, the curriculum was approved by the University Grants Commission and PPDM was launched in 2005. Within the last twenty-five years since its inception, PPDM went through several reviews. The first review was conducted by myself and a colleague, Graham Marsh, from RMIT University, Australia, where I was working at that time. These reviews helped shape and improve PPDM’s curriculum, enabling the program to gain its present strength. While there are other disaster management academic programs in Bangladesh, PPDM was the first and foremost, and in some ways subsequent programs were inspired by it. From its inception, a key strength of PPDM was its link with disaster management practitioners, who brought in their valuable practical knowledge and expertise for the benefit of students. Bangladesh is one of the countries in the world most at risk to natural and human-induced hazards, so an educational program like PPDM is highly relevant to develop and provide the supply of much-needed disaster management experts. Therefore, the idea of also running an undergraduate disaster management educational program is relevant in the Bangladeshi context to grow a cadre of young disaster management professionals who would have potential for future leadership roles. They in turn can also serve as guest lecturers and maintain the continuity of PPDM’s practice-based approach. I applaud Brac University for its perseverance and vision in successfully sustaining PPDM over a quarter century and also extending it to the undergraduate level. My sincere best wishes to all the current and future PPDM students, alumni and academics for their mission to make Bangladesh resilient and safe from disasters.150

Masters and Bachelor Programs on Disaster ManagementImon Chowdhooree, PhD Associate Professor, Department of Architecture Assistant Director, Postgraduate Programs in Disaster Management (PPDM) BRAC UniversityThe contemporary world is increasingly threatened not only by natural extreme events but also by anthropogenic disasters such as terrorism, war, armed conflict, security threats, environmental pollution, and technological hazards. These challenges significantly affect socio- economic stability. In addition, issues of gender and intersectionality in disaster management must be addressed in a more inclusive and integrated manner. In response to these global and national needs, academic programs in disaster management must cover a wide range of interdisciplinary areas, including humanitarian assistance, peacebuilding, disaster risk reduction, counter-terrorism, security studies, environmental planning, climate change adaptation, risk mitigation and many more. BRAC University has played a pioneering role in this field through its Postgraduate Programs in Disaster Management (PPDM), established in 2005 under the Department of Disaster Management. This program was the first of its kind in Bangladesh and the South Asian region within a university structure, contributing significantly to the development of a practice-oriented academic and research domain. The program offers postgraduate certificates, diplomas, and a Master of Disaster Management (MDM) degree. My involvement with the program began in 2010 after completing a Master of Urban and Regional Planning with a specialization in Disaster Management Planning in Hawaii, USA. Initially engaged in teaching theoretical courses, I later became actively involved in curriculum development. I chaired the committee responsible for revising the MDM curriculum, which was approved by the University Grants Commission in 2022. The revised MDM program introduces five specialized streams: Disaster Risk Reduction; Social Safety and Community-based Adaptation; Human Security and Humanitarian Crisis Management; Climate Change Adaptation and Sustainable Development; and Public Policy and Organizational Strategies. These streams allow students to pursue focused expertise while addressing the growing demand for specialization in the diverse field of disaster management. Building on this advancement, the department envisioned expanding into a full-fledged academic unit by introducing an undergraduate program. At the same time, to reflect this broader scope, the department proposed a new identity: the Department of Disaster Management and Environmental Studies (DMES). The department aims to offer academic programs focused on designing resilient social and built environments, as well as conserving and restoring natural ecosystems through mitigation measures, adaptation strategies, risk-reduction technologies, and humanitarian standards.151

These programs address a wide range of natural and human-induced hazards, environmental degradation, and emerging global threats. Its vision is to provide internationally recognized, high- quality education in the fields of hazard science, disaster management, disaster risk reduction, security, climate change, environmental science, and humanitarian assistance. To achieve this vision, a curriculum committee—chaired by me—was formed to develop the Bachelor’s program. The curriculum has been designed to ensure that all graduates acquire a comprehensive understanding of disaster management, along with in-depth knowledge in a specialized field. The three areas of specialization are: Humanitarian Response, Climate Change Studies, and Environmental Risk Reduction Technology. As long as communities around the world continue to require assistance and support, there will remain a strong demand for professionals in humanitarian and disaster management. Graduates will have career opportunities in administration, research, fundraising, grant management, training, consultancy, advocacy, relief operations, mediation, peacebuilding, risk reduction, economic development, planning, and infrastructure design at both national and international levels. They will also be well-positioned to assume leadership roles such as program directors, coordinators, planners, policymakers, and facilitators of humanitarian and emergency response initiatives.152

Photo Gallery153

Photo Gallery153

Photo Gallery154

E D I T E D B Y I M O N C H O W D H O O R E E , P H D , M U H A M M A D F E R D A U S , S A D I A S A I M A , M A H I A F A R S U M I S L A M A N D F A R A H I S L A M A E S H A