The restoration of the Gulshan-Banani Lake, designated as an Ecologically Critical Area (ECA), could generate benefits worth Tk 300,000 crore over a 20-year period, according to a recent study.

Conducted by the ReWET consortium, this report is the first comprehensive economic valuation of an urban wetland in Bangladesh. Titled “Primary Economic Analysis for Climate Impacted Dwellers-led Agro-Ecological Stewardship for Restoring Wetlands (Re-WET),” the study estimates the economic value of the ecosystem services provided by the Gulshan-Banani Lake.

The lake forms part of the Gulshan-Banani-Baridhara wetlands ecosystem. Adjacent to it lies the Korail slum, the largest informal settlement in Bangladesh, which houses over 250,000 residents.

The study models a 20-year restoration scenario, where local residents are trained as wetland stewards. It finds that restoring the Gulshan-Banani Lake through a co-productive process with Korail’s residents could generate benefits worth Tk 10,600 crore annually, culminating in a total value of Tk 300,000 crore over two decades.

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The investigation was conducted over a 2-kilometre stretch of the lake and aggregated various ecosystem service values and avoidable costs. Key highlights include:

· Fisheries and Aquaculture: Annual contributions of Tk 8.635 crore, providing livelihoods for local communities.

· Climate-Smart Agriculture: Valued at Tk 12.5 crore annually.

· Municipal Water Substitution: Valued at Tk 18.75 crore per year.

· Climate Regulation Services: Carbon sequestration alone generates Tk 84 crore annually, playing a critical role in combating climate change.

· Flood Regulation: Annual benefits of Tk 43.24 crore from water retention and restoration.

· Cultural and Recreational Services: Green-blue spaces enhance quality of life and eco-tourism opportunities, contributing Tk 200 crore annually.

· Education and Cultural Services: Civic and ecological education, intellectual exchanges, scientific research, and community programs contribute Tk 3,002 crore annually.

· Biodiversity Value: Unique flora and fauna preservation generates Tk 37 crore annually.

· Land Value: Restoration could lead to an increase in land value estimated at Tk 5,000 crore annually.

Challenges and Environmental Impact

Despite its importance, the Gulshan-Banani Lake faces severe pressure from rapid urbanisation, pollution, and encroachment. Korail’s socio-economic challenges are intrinsically tied to the wetland’s degradation. The unchecked pollution, resulting from untreated sewage, solid waste dumping, and inadequate waste management infrastructure, disproportionately impacts the vulnerable Korail population.

Recommendations for Restoration

The ReWET report outlines several pathways for restoration:

· Establishing protected buffer zones along the lake.

· Constructing wastewater treatment plants.

· Reintroducing native vegetation and species to restore habitats.

· Promoting climate-smart agriculture and aquaculture among locals.

· Providing micro-financing to support green businesses.

· Introducing payment for ecosystem services.

· Encouraging public-private partnerships for restoration efforts.

Project Overview

The ReWET project is part of the Reversing Environmental Degradation in Africa and Asia (REDAA) programme, funded by the UK Foreign, Commonwealth and Development Office (UK FCDO) and managed by the International Institute for Environment and Development (IIED).

Led by the University of Sheffield, UK, the project is implemented by the River & Delta Research Centre (RDRC), Dhaka, with assistance from experts in urban environmental design, finance, and policy from Smith College, USA, and Sheffield Hallam University, UK.

Employing a rigorous Total Economic Value (TEV) framework, the report combines qualitative and quantitative approaches for data collection, valuation, and scenario-based modeling.

Expert Insights

Saifullah Khaled, a climate finance expert and Assistant Professor in Finance at Sheffield Hallam University, said the ReWET report demonstrates the immense value of investing in nature-related interventions. It’s an effort to show broader stakeholders the value for money in restoring wetlands.

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“The potential of value generation from Korail Lake, Tk 10,600 crore per annum, and Tk 300,000 crore over a 20-year period is just the tip of the iceberg. There are many more externalities, multiplier effects, or co-benefits we couldn’t even capture in this ecosystem services valuation,” he said.

Efadul Huq, Assistant Professor in Environmental Science & Policy and Urban Studies at Smith College, stressed the urgent need for restoration of Dhaka’s urban wetlands, because urban wetlands are critical ecological infrastructure and for keeping social inclusion and empowerment front and center in restoration efforts.

“We need to co-produce restored urban wetlands with local residents, and recognize the knowledge, experiences, and needs of the most vulnerable urban dwellers in that process,” he said.

Mohammad Azaz, the RDRC Chairman, said the ReWET project is a collaborative effort to restore Gulshan-Banani Lake and they are working closely with RAJUK, Dhaka North City Corporation, the District Commissioner’s Office, and the Department of Environment.

“By working with multiple stakeholders, from government agencies to residents, we aim to create a model of urban wetland restoration that not only revives ecological functions but also enhances the livelihoods, resilience and well-being of the people who depend on these critical ecosystems,” he said.