2018 Reports

Urban Wetlands for Flood Control and Climate Change Adaptation in
Colombo, Sri Lanka

De Mel, Manishka; Hettiarachchi, Missaka

Colombo’s urban wetlands provide critical flood control and climate adaptation services for the metropolitan region, which is highly vulnerable to coastal flooding, storm surges, and extreme rainfall events. The Colombo Flood Detention Area and associated wetlands historically mitigated floods, but urban expansion, land conversion, and ecological degradation have reduced their effectiveness. Climate change, through increased rainfall intensity, sea level rise, and saline intrusion, further threatens these wetlands’ capacity to buffer floods. Strengthening resilience requires integrated, ecosystem-based adaptation measures, informed by localized climate risk data, downscaled projections, and pilot interventions. Protecting and restoring wetlands while coordinating with communities and infrastructure planning is essential to safeguard dense settlements, critical infrastructure, and ecosystem services in the face of future climate impacts.