Wetlands as a Nature-based Solution for Urban Water Management

Cities occupy less than 2% of the Earth’s surface, but more than half of the world’s population resides in them. As per the United Nations Department of Economic and Social Affairs (UNDESA), the urban population is expected to increase to around 7% thereby increasing pressure on these areas and the resources therein. Urban areas are among the significant contributors to climate change and where the impact on natural resources is the most experienced, particularly water resources. Major cities of the world are experiencing water scarcity. Climate change has altered the water cycle, causing increased flooding and prolonged droughts. The impacts of climate change, compounded with increasing urbanisation, inadequate management and governance, have resulted in urban water-related issues such as water resources degradation due to contamination, lack of wastewater treatment, groundwater depletion, and water-related disasters. Given the uncertainty of the climate and existing capacities to meet the demands of rapid urbanisation, the traditional grey infrastructure is no longer sustainable. Combining grey infrastructure with nature-based solutions, such as wetlands, therefore, offers a sustainable and resilient approach to managing urban water resources. These hybrid approaches not only contribute towards efficient and effective water resources management but also provide a buffer from the impacts of extreme events and ecosystem services, contributing to improved health of urban dwellers. Recently, hybrid approaches of integrating nature-based solutions with grey infrastructure have been gaining prominence worldwide. A number of global cities have drifted towards these integrated approaches, including Copenhagen, San Francisco, Seattle, and Singapore. Given the varied ecosystem services and values they offer to society, wetlands form the core of its ecological and economic security. Their contribution towards environmental and resource sustainability has now gained recognition. For example, the city of Columbia in Sri Lanka has integrated wetlands into the city’s flood defence system while providing co-benefits such as enhanced urban and peri-urban agriculture. The lack of studies on the role of wetlands as a nature-based solution and inadequate governance framework has not only ignored the role of wetlands in urban water management but also led to the rapid decline of this fragile ecosystem. Amidst the rapidly increasing climate crisis, it is pertinent to integrate wetlands through a multi-stakeholder and inter-sectoral collaboration and mainstream wetlands into urban planning and administration. This chapter explores the role of wetlands as a nature-based solution in urban water management through a case study approach and suggests a framework for mainstreaming wetlands conservation and management in developmental plans and programmes for vertical upscaling.