Colombo, Colombo (FUA), Sri Lanka
City population: 639818
Duration: 2012 – 2021
Implementation status: Completed
Scale: Meso-scale: Regional, metropolitan and urban level
Project area: unknown
Type of area: Freshwater setting (e.g. river, channel, lake, pond)
Last updated: May 2025

Sri Lanka faces multiple natural hazards, including tropical storms, flash floods, and landslides. As the country's urban population has grown, development projects have encroached on wetlands, compromising their natural flood protection, air and water purification, and carbon storage capabilities. Additionally, hilly regions are at risk of landslides, particularly during the monsoon season, posing significant threats to vulnerable communities (4). To address these challenges, the World Bank and the Sri Lankan government collaborated on the Metro Colombo Urban Development Project. This initiative focused on nature-based solutions (NBS) as cost-effective and sustainable approaches to risk management (4). By strengthening natural processes and ecosystem services, the project aimed to mitigate hazards such as floods, erosion, and landslides (4). Technical assessments by the World Bank highlighted the importance of wetlands in flood protection, leading to efforts to protect and restore 20 square kilometres of freshwater lakes, wetlands, and swamps (1, 4). The project supported the Sri Lankan government in reducing flooding in the Colombo Water Basin and enhanced local authorities' capacity to manage infrastructure and services. It prioritised metropolitan investments to mitigate the physical and socioeconomic impacts of flooding and aimed to build long-term capacity for urban management and local service delivery (6).

Wetland in Colombo
Wetland in Colombo
Ministry of Urban Development and Housing

Overview

Nature-based solution

  • Blue infrastructure
  • In-land wetlands, peatlands, swamps, and moors
  • Green areas for water management
  • Sustainable urban drainage systems
  • Parks and urban forests
  • Pocket parks/neighbourhood green spaces

Key challenges

  • Climate action for adaptation, resilience and mitigation (SDG 13)
  • Climate change adaptation
  • Green space, habitats and biodiversity (SDG 15)
  • Green space creation and/or management
  • Habitat and biodiversity restoration
  • Regeneration, land-use and urban development
  • Regulation of built environment
  • Landslides reduction
  • Water management (SDG 6)
  • Flood protection
  • Health and well-being (SDG 3)
  • Creation of opportunities for recreation
  • Enabling opportunities for physical activity
  • Inclusive and effective governance (SDG 16)
  • Disaster-risk reduction

Principal problems in Functional Urban Area (FUA)

  • Climate-Related Hazards
  • Urban flooding (stormwater)
  • Extreme weather events (e.g. storms, hurricanes)
  • Landslides & mudslides
  • Degradation of carbon sinks
  • Environmental Degradation
  • Air pollution
  • Physical water retention and availability
  • Land use and Socio-economic change
  • Rapid urbanization
  • Health, Well-being and Social cohesion
  • Physical health harm (from pollution, wildfire, extreme temperature)

Key priorities

Climate action (adaptation and/or mitigation), Biodiversity (conservation and/or restoration)

Focus

Creation of new green areas, Creation of any other green urban spaces, Maintenance and management of urban nature, Maintenance or upgrade of exisiting green spaces (e.g. parks), Ecological restoration of ecosystems, Ecological restoration of existing green spaces, Restoration of wetlands (other types than peatlands and mangroves, e.g. seagrass), Restoration and protection of ecosystems (including water ecosystems), Protection of natural ecosystems, Protecton and enhancement of wetlands (other types than peatlands and mangroves, e.g. seagrass), Habitat restoration, Strategy, plan or policy development, Creation of city-wide or neighborhood climate adaptation or mitigation strategies/programs, Development of disaster-risk prevention strategies (e.g.fire management, flood alleviation scheme)

Project objectives

To support the Government of Sri Lanka in reducing the flooding in the catchment of the Colombo Water Basin (1) To strengthen the capacity of local authorities in the Colombo Metropolitan Area to rehabilitate, improve and maintain local infrastructure and services through selected demonstration investments (1) To restore the city wetlands as a nature-based solution, allowing them to serve as flood retention and recreational areas (1) To complement ongoing urban regeneration programs of the Government of Sri Lanka by reducing the physical and socioeconomic impacts of flooding in the Metro Colombo Region and improving priority local infrastructure and services (5) To create recreational space, such as parks, walkways, and other public open spaces and improvements to existing places (6)

Implementation activities

- Improvements of main/primary canals and lakes: Protection of canal banks and clearing of reservations, repairs locks and gates in the canal systems, widening of bridges in the canal systems, tunnel constructions, restoration of lakes associated with the canals and wetlands through dredging and environmental enhancement of the immediate surroundings (6) - Rehabilitation of secondary/tertiary canals (6) - Improvement of stormwater drainage: Improvements to localised micro drainage and interception of unauthorised effluent discharges (6) - Urban landscaping for recreation and city beautification: Creation of recreational space such as parks, walkways other public open spaces and improvement to existing places (6) - Conservation of heritage around Beira Lake and other important sites including natural habitats for the promotion of urban tourism (6) - Public Health & Sanitation support: Solid waste management and interception of unauthorized discharges to the canal system, improving the public sanitary facilities (6) - Rehabilitation/development of small/medium scale municipal infrastructure: rehabilitation and renovation of libraries, markets, public toilets, playgrounds and common amenities (6) - Urban/municipal Road resurfacing and roadside drainage improvement (6)

Climate-focused activities

Climate change adaptation:

  • Implement measures that prevent/manage desertification, soil erosion and landslides
  • Restore mangroves, marshes, reefs and wetlands to dissipate the effects of storms and floodwaters
  • Implement sustainable urban drainage schemes to manage stormwater
Communities vulnerable to environmental hazards or climate change impacts
Yes

Specification of climate or environmentally vulnerable communities

Low-income neighborhoods, Communities located in floodplains

Biodiversity conservation or restoration-focused activities

Biodiversity restoration:

  • Rehabilitate and restore damaged or destroyed ecosystems

Main beneficiaries

  • Local government/Municipality
  • Citizens or community groups
  • Marginalized groups: Socio-economically disadvantaged populations (e.g. low-income households, unemployed), Vulnerable populations in disaster-prone areas

Governance

Management set-up

  • Government-led

Type of initiating organisation

  • National government
  • Local government/municipality
  • Public sector institution

Participatory approaches/ community involvement

  • Co-planning (e.g. stakeholder workshops, focus groups, participatory mapping)
  • Dissemination of information and education
  • Consultation (e.g. workshop, surveys, community meetings, town halls)

Details on the roles of the organisations involved in the project

- Sri Lanka's government: initiating and co-financing agent (2) - Ministry of Urban Development and Housing: Implementing and executing agency (2) - World Bank and Sri Lanka's Government: co-financer (1) - Implementing agencies (3, 6, 7): Sri Lanka Land Reclamation and Development Corporation (SLLDC) Urban Development Authority (UDA) Colombo Municipal Council (CMC) - Urban Local Authorities involved (6, 7): Colombo Municipal Council (CMC) Dehiwela-Mount Lavinia Municipal Council (DMLMC) Sri Jayawardenapura-Kotte Municipal Council (SJ-KMC) Kolonnawa Urban Council (KUC)

Project implemented in response to ...

... an EU policy or strategy? Unknown
... a national policy or strategy? Yes (The project’s high-level objective was aligned with two of the main strategic objectives of the World Bank’s Sri Lanka Country Assistance Strategy (CAS) FY 09–12: improving infrastructure provision to strengthen competitiveness and enhancing the quality of services (3) The goals and outcomes of improving local infrastructure in Metro Colombo and protecting the Colombo Metropolitan Region from flooding are aligned with the National Physical Planning Policy as well as Plan Sri Lanka 2011-2030 (3))
... a local policy or strategy? Yes (Urban wetland parks and the improvement of public spaces complement the plans envisaged in the Colombo City Development Plan 2022-2030 prepared by the Urban Development Authority (UDA) (3))

Type of enablers

Capacity-building projects

Financing

Total cost

More than €4,000,000

Source(s) of funding

  • Public national budget
  • Multilateral funds/international funding

Type of funding

  • Earmarked public budget
  • Loan

Non-financial contribution

Unknown

Impacts and Monitoring

Environmental impacts

  • Climate change
  • Lowered local temperature
  • Achieved lowered local temperature
  • Environmental quality
  • Improved air quality
  • Achieved improved air quality
  • Water management and blue areas
  • Increased protection against flooding
  • Achieved increased protection against flooding
  • Enhanced protection and restoration of freshwater ecosystems
  • Achieved enhanced protection and restoration of freshwater ecosystems
  • Green space and habitat
  • Increased green space area
  • Achieved increased green space area
  • Increased presence and recovery of wild species
  • Achieved increased presence and recovery of wild species

Economic impacts

  • Increase of green jobs (e.g. paid employment positions)
  • Achieved increase of green jobs (e.g. paid employment positions)
  • More sustainable tourism
  • Achieved more sustainable tourism
  • Increased property prices
  • Expected increased property prices
  • Other

Socio-cultural impacts

  • Social justice and cohesion
  • Improved liveability
  • Achieved improved liveability
  • Improved access to urban green space
  • Achieved improved access to urban green space
  • Health and wellbeing
  • Gain in activities for recreation and exercise
  • Achieved gain in activities for recreation and exercise
  • Education
  • Increased awareness of NBS and their benefits
  • Achieved increased awareness of NBS and their benefits
  • Safety
  • Increased perception of safety
  • Achieved increased perception of safety

Type of reported impacts

Presence of formal monitoring system

Yes

Presence of indicators used in reporting

Yes

Presence of monitoring/ evaluation reports

Yes

Availability of a web-based monitoring tool

No evidence in public records

Potential risks of implementation and trade-offs

Unknown

References

1.
The Global Program for Nature-Based Solutions for Climate Resilience (2024). Metro Colombo Urban Development Project. Accessed on October 8, 2024, [Source link];
2.
World Bank Group (2023). Metro Colombo Urban Development Project. Accessed on October 8, 2024, [Source link];
3.
The World Bank (2022). IMPLEMENTATION COMPLETION AND RESULTS REPORT . Accessed on October 8, 2024, [Source link];
4.
Global Facility for Disaster Reduction and Recovery (2023). Mitigating Disaster Risk in Sri Lanka through Nature-Based Solutions. Accessed on October 8, 2024, [Source link];
5.
Metro Colombo Urban Development Project (n.d.). Metro Colombo Urban Development Project. Accessed on October 8, 2024, [Source link];
6.
Ministry of Defence and Urban Development (2011). Environmental Management Framework. Accessed on October 8, 2024, [Source link];
7.
Ministry of Defence and Urban Development Project (2024). RESETTLEMENT ACTION PLAN (RAP) Rehabilitation of St. Sebastian South Canal. Accessed on October 8, 2024, [Source link];
8.
World Population Review (2024). Colombo, Sri Lanka Population 2024. Accessed on October 8, 2024, [Source link];
9.
Food and Agriculture Organization of the United Nations (2018). Assessing and Planning City Region Food System. Accessed on October 8, 2024, [Source link];
Site visit in one of the Colombo's Wetlands
Site visit in one of the Colombo's Wetlands
Ministry of Urban Development and Housing
naturescapes bannerInformation about this nature-based solution was collected as part of the Naturescapes project funded by the European Union under Grant Agreement No 101084341.