Often called “nature’s kidneys”, wetlands play a key role in balancing ecological processes, with benefits to people. Whether naturally occurring swamps and marshes, or human-made ponds and rain gardens, wetlands can act as natural wastewater management, by minimizing pollution, controlling flooding risks, and mitigating extreme urban heat island effects.
Urban wetlands can be particularly valuable for these benefits, and understanding how they function is absolutely necessary to reverse their degradation and improve urban liveability in a holistic fashion. Conserved and restored urban wetlands have the potential to reduce urban flooding while buffering storm surges, since they act as sponges, potentially shielding urban dwellers from extreme weather impacts such as flooding. In the process, these wetlands restore water quality and supply through natural filtration, by removing unwanted pollutants. In addition to acting as remarkably effective carbon sinks, wetlands provide habitat and breeding sites for approximately 40% of plants and wildlife; restoring or conserving wetlands in urban settings could help maintain biodiversity in cities and their surroundings.
Urban wetlands can also revive cities and increase human wellbeing. Known as “blue-green infrastructure”, wetlands and other natural features incorporated into cityscapes can improve urban dwellers’ health, through encouraging physical and recreational activities, providing outdoor relaxation spaces, and improving social life from more frequent human interactions and more access to “green spaces”, something that humans are programmed to need.
SEI’s Initiative on City Health and Wellbeing uses contemporary approaches to understand heterogenous urban form impacts on general liveability, while highlighting the health benefits of green infrastructure in developing cities. Economically, urban wetlands restoration can be a part of ecotourism, attracting visitors while generating revenue necessary for their maintenance.
Nearly five decades after its adoption, the Ramsar Convention on Wetlands stays committed to promoting the sustainable use of all wetlands and minimizing their loss through national and global cooperation, as well as policy developments. In 2012, the 11th Conference of Parties to the UNFCCC formulated the Resolution XI.11 principle to raise awareness and recognition of both small- and large-scale wetlands within urban planning.
Protecting and restoring urban wetlands will be a huge challenge: cities around the world are growing, particularly in low-income countries. The accompanying upsurge in demand for land puts wetlands especially at risk, as they are usually converted to built-up areas. Loss of wetlands has implications for climate impacts for growing urban centres.
Policy makers, urban planners, city managers and developers stand at the core of creating climate-resilient cities, and one tool they have is integration and promotion of urban wetland restoration. Some of these practices include:
- Establishing a long-term restoration plan to establish a self-sustaining complementary system for urban wetlands’ ecosystems, including protecting wildlife.
- Incorporating “biophilic design” principles, for example in constructed and natural wetlands, by including different landscape features such as elevated boardwalks and piers. These improve access and link urban residents to different designated zones within and around wetlands, maximizing “nature’s health benefits”.
- Setting up and implementing relevant governance and development frameworks on urban and peri-urban wetlands protection.
- Assessing and resolving the root causes of wetland degradation, such as policies that allow sprawling developments without conservation offsets or wetland protections, in order to provide alternative solutions, for instance blue-green infrastructure, through existing policies and practices.
- Promoting “placemaking” activities within different levels in urban communities, to ensure degraded wetlands are free from unwanted debris through regular clean-ups. Placemaking is an aspect in urban planning and management to make public spaces more people-centred towards improving their overall well-being.
- Involving community in local and scientific wetland restoration through citizen science, ensuring the restored wetlands are maintained by local residents for sustainability.
Researchers at SEI have also explored the promises and pitfalls of nature-based solutions, in which urban wetlands play a key role. More research will follow from SEI’s programmes, which are intended to bring science to policy in protecting urban wetlands and enhancing human wellbeing in cities, in a world in which cities will only continue to grow.