Restore wetlands and/or coastal ecosystems to dissipate the effects of flooding and/or storms

The Beddagana Wetland Park is located in Sri Jayawardenapura Kotte, Sri Lanka's administrative capital. The wetland park plays an important role in flood regulation and keeping the city cool during periods of extreme heat. The city is located in the Colombo district and the project contributes to the flood management goals of the Metro Colombo Urban Development Project (MCUDP). It demonstrates how a wetland can be preserved while promoting eco-tourism and improved livability in the city. The target area is located within the Sri Jayewardenapura-Kotte municipality and is a part of Parliament Lake. While focusing on the protection of the wetland habitat as a flood-retention area, the project also supports selecting investments aimed at the protection and landscaping of key areas within the target area to improve livability for local people living in and around the area, while providing access to much-needed recreational space. [2, 7]

The Bluebelt programme in Staten Island was implemented as it "preserves natural drainage corridors including streams, ponds, and wetlands, and enhances them to perform their functions of conveying, storing, and filtering runoff precipitation or stormwater". (Ref. 2). By delivering "stormwater to engineered systems that are designed to mimic natural streams and ponds which...meander or wind back and forth, the water slows down naturally" (Ref. 1). These actions are intended to "help control flooding, pollution and erosion" (Ref. 2), whilst also providing open green areas for both local communities and a "diverse habitat for wildlife" (Ref. 2). Beginning in 1990, the Bluebelt programme has undergone continual expansion, recognising that "as New York City prepares for rising sea levels and heavier rains due to climate change, Bluebelts offer a natural and effective solution for stable and sound stormwater management" (Refs. 2 & 4). The Bluebelt now includes approximately 400 acres of freshwater wetland and riparian stream habitat and 11 miles of stream corridor (Ref. 4).

The project has seen the "installation of rock structures to reduce the energy of the water that is drained by conventional rainwater galleries and the strategic planting of certain plant species that, through phytoremediation, can mitigate the diffuse pollution that affects the body of the river" (Ref. 1). In combination, "these solutions aim to prevent erosion and landslides on the banks, stop the siltation of the river, improve water quality and strengthen the linear park as a leisure space increasingly demanded by the population in its surroundings" (Ref. 1). A demonstration project which occurred under ICLEI's INTERACT-Bio project, the implementation of NBS has also been accompanied by other measures which saw Lake Cabrinha be de-silted, a walking path, benches, and playground be built and LED lighting be installed" (Ref. 1).

Monavale Vlei is an important wetland area within the city of Harare, characterised by miombo woodlands that play an important role in the fragile ecosystem of the Manyame catchment basin, the main supplier of water for the city of Harare and its suburbs. Throughout the years, Monavale has been subjected to a number of threats such as construction developments, dumping of waste, fires, illegal farming, invasive plants, informal agricultural practices and loss of biodiversity. To address some of these challenges the local community organized itself into a group - Conservation Society of Monavale (Cosmo) Trust, to protect the area and, with the help of the municipality of Harare and some international bodies, implemented a series of actions designed to protect the wetland and reduce the loss of biodiversity, among many others. In 2009 the NGO was awarded a United Nations Development Programme Global Environment Facility Small Grant. The intervention had 3 objectives: to restore parts of the wetlands, to advocate with the local and international authorities for the legislative protection of the wetlands, and to engage the scientific community in research regarding the wetlands. This enabled Cosmo to restore Monavale vlei to an almost pristine wetland state, and other UN funding has made possible several training and awareness projects for a wide range of audiences. (1,2,3)

The municipal government of the Yiwu city in China has launched the Green Lungs of the City Project (GLCP) in 2019. The overarching goal was to build a green lung, which will create more green spaces for residents in Yiwu, mitigate environmental pressures and improve the city's resilience to climate change. Under the project, a green corridor was created to reconnect the roads, rivers, ponds and lakes where different tree species were planted. Additionally, wetlands were constructed and restored to improve resilience against climate change disasters. The project is still in the ongoing phase, and a forest-wetland ecological park is under development in the city's central area. The GLCP aims to use different types of NBS elements to promote sustainable urban development and to provide multiple ecosystem services to the citizens in a highly urbanised area. [1]

The marshes in southern Iraq, formed by the Tigris and Euphrates Rivers, are home to one of humanity’s oldest cultures, once the third-largest wetlands in the world. The Eden In Iraq wastewater garden project started as a humanitarian project that has developed as a necessity for the people of Al Chibaish and the localities surrounding the town. This water remediation project holistically looks at wastewater, trying to include this type of water and its nutrients in a sustainable form by using it to create green spaces. The Eden project in Iraq regards human waste as a valuable source of nutrients and freshwater, which can add to local greenery and landscape beauty if properly treated close to its source. From a climate change point of view, the project focuses on the creation of a wetland with wastewater that can support a garden within the marshes of Iraq. Marsh restoration is a powerful tool against warming temperatures and loss of vegetation, especially in arid areas such as Iraq. From a biodiversity point of view, the project bares a great deal of significance as marshes support a myriad of rare wildlife and rich biodiversity. (1,2,3)

Extensive and low-lying, Suriname’s coastal region has been identified as highly vulnerable to climate-induced sea-level rise (Ref. 1). "Momentarily the most endangered community by sea-level rise in the whole of South America and the Caribbean", the Suriname Building With Nature project has seen "wooden, water penetrable dams...being built to trap sediment and replant mangroves" (Ref. 1). Prior to the implementation of the Building With Nature project, no mitigation measures had been undertaken to protect the area, and "human interference ha[d] converted mangrove areas to agricultural land, fishing ponds and settlements", with the loss of stabilisation provided by the mangroves meaning that "the coast has become susceptible to flooding and erosion, losing up to 27 meters of land in one year" (Ref. 1). It has caused "displacement of local habitants and loss of livelihoods, [with]...the local population...and its fisheries, farms, and important religious and cultural sites [being] at risk to frequent flooding and land degradation" (Ref. 1). The Building With Nature approach is touted as being "essential for mangrove and biodiversity conservation and the enhancement of the quantity of the blue carbon sequestered in coastal areas" (Ref. 2).

The City of Fort Collins is "taking steps to restore flows, fish passage, and ecological function" of Colorado's Cache la Poudre River (Ref. 6). The river was "heavily manipulated for irrigation and mining" throughout the early 20th century (Ref. 6), and today continues subject to the impacts of gravel mining, agriculture and urbanisation (Ref. 1). Regional climate change predictions further complicate our ability "to understand how the river’s hydrology and ecology may respond to warming climate scenarios" (Ref. 1).
The City of Fort Collins was, therefore "invested heavily in this urban river through extensive planning efforts, purchase of approximately 700 hectares of lands within the river’s floodplain, projects to address stormwater control and conveyance, water quality management, and acquisition of in-stream flow water rights", and in 2011, the City’s Natural Areas Department published the Cache la Poudre River Natural Areas Management Plan which outlined "opportunities and challenges in supporting the river’s ecological function and reducing risks to life and property during significant flood events", particularly through the implementation of nature-based solutions (Ref. 1). A suite of nature-based solutions has since been proposed and implemented by the City of Fort Collins, two of which are the Sterling Pond Ecological Restoration (also referred to as North Shields Ponds), and the McMurry Natural Area Ecological Restoration (Refs. 1 and 2).

Resilient Islands is a project thought and directed by the Nature Conservancy (TNC) and the International Federation of the Red Cross and Red Crescent Societies (IFRC) in 3 Caribbean island nations. It is a project at the intersection between conservation and disaster risk reduction and it comprises actions implemented in the Dominican Republic, Granada, and Jamaica. The negative impacts of climate change are already affecting people, homes, businesses and infrastructure in Caribbean nations. In response to increasingly dangerous hurricanes and rising vulnerability, Resilient Islands will address the need for urgent action by developing adaptation toolkits, best-practice models and access to funding. Caribbean nation islands are the world's most vulnerable to the impacts of climate change. Coastal flooding and erosion caused by hurricanes and severe storms threaten lives, homes, jobs, and infrastructure. Grenville is a coastal town, the second largest town in Grenada, with a population of around 2,400. It is highly susceptible to flooding and has seen increased coastal erosion in recent years due to the degradation of the fringing reefs, its first line of sea defence. Since 2017, TNC and the IFRC have collaborated with governments, communities, and partners in Grenada and Greenville to develop national plans for a more sustainable future through nature-based disaster risk management and there this is how this intervention was born. (1,4)

Around 90% of Guyana’s population lives in an area that is below sea level, with many inhabiting flood-prone areas along the coast. The coastal plains are also home to about 75% of the country’s economic activities, including almost all of Guyana’s agricultural production. Over the years, degradation and loss of mangrove forests have resulted in increased coastal flooding and saltwater inundation of agricultural land. Mangroves contribute substantially to sea defence in Guyana by damping wave action and reducing wave energy, trapping sediments and stabilizing shoreline substrates while playing an important role in carbon sequestration.
The Guyana Mangrove Restoration Project was executed during 2010-2013 under the National Agricultural Research & Extension Institute. Following completion of the Project phase and given the importance of mangroves to Guyana’s coastal defences, mangrove restoration and management were integrated into NAREI (the National Agricultural Research and Extension Institute), a national institution that promotes climate-smart agriculture and resilient citizens. (1,2)