Increased protection against flooding

The main rivers that cross Lilongwe are the Lilongwe, Lingadzi, Nankhaka and Chankhandwe Rivers, of which the Lilongwe River is the biggest and longest river and the primary source of water for Lilongwe city's residents. At 200 km long, besides its primary function, the river also supports several informal settlements and provides ecological, recreational, cultural and economic benefits. Despite these important functions that the river offers, it is still facing threats such as pollution, urban agriculture, sand mining, climate change effects, and a loss in the biodiversity of fauna and flora that this watercourse hosts. As it sustains a population of approx. 1 mil. inhabitants, the local authorities were interested in finding solutions to address the above threats. As early as 2016, ICLEI ( Local Governments for Sustainability), an international NGO that promotes sustainable development, worked alongside Lilongwe City Council and other stakeholders to protect the river as well as the people depending on it and implemented several actions, with the help of the local community. Eventually, this collaboration led to the issuing of a strategic plan for a sustainable and functional ecological corridor system in the heart of Lilongwe City. The Ecological Corridor aims to transform Lilongwe into a green, clean, prosperous, and resilient city, by ensuring the protection of its urban natural assets, and advancing complementary nature-based solutions. 1,2,3)

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).

A rain garden has been implemented at the Fazenda Lagoa do Nado Municipal Park in Belo Horizonte. The rain garden has been created as "a solution that contributes to the runoff of rainwater, allowing the water to be filtered through vegetation and infiltrate into the soil", with this type of solution being recognised as a method which "recharge[s] the water table, increases biodiversity, improves the local microclimate and air quality" (Ref. 1). The rain garden has been created as a demonstration project within the wider INTERACT-Bio project which is led by the global Local Governments for Sustainability network, ICLEI (International Council for Local Environmental Initiatives) (Ref. 1). As summarised by President of the Municipal Parks and Zoobotany Foundation of Belo Horizonte, Sérgio Augusto Domingues, “This is an important experiment that enables solutions based on nature. The idea is that it, like other mechanisms, complements macro-drainage interventions, helping the city to be more resilient to extreme events related to climate change" (Ref. 3).
According to the Municipality of Belo Horizonte, the Multiannual Government Action Plan (PPAG) aims to implement 30 rain gardens in the municipality by 2025, each garden having an area of ​​150 square meters (Ref. 7).

Mauritania is one of the Sahelian countries most severely affected by the periods of drought occurring since 1968. The resulting desertification is exacerbated by human activities, which have compounded climatic factors, with direct consequences for an already precarious situation. Environmental degradation, responsible for the dangerous displacement of sand dunes in Mauritania, has wiped out homes, livestock and livelihoods throughout the desert country. In Nouakchott, Mauritania’s capital and biggest city, the coast are protected by a fragile wall of dunes at risk from natural erosion, sand mining, grazing of livestock on dune vegetation, and careless abuse of the landscape for leisure like dune racing. In this scenario, protecting the dunes is a priority, and the government is using World Bank financing to overcome the challenge. From a climate change perspective, the intervention addresses accelerating erosion that allows seawater to wash into the city, assaulting buildings, roads, fresh water supply and public space. From a biodiversity perspective, the intervention aims at sustaining the balance between the food for the livelihoods of the local population and the preservation of the rich coastal biodiversity. (1,2)

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)

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 Bishkek once had the status of one of the greenest and most pleasant cities in the Soviet Union. The situation has deteriorated from year to year, so much so that in 2009 Bishkek was ranked sixteenth in the list of the thirty dirtiest cities in the world in a study published by The Blacksmith Institute, an American NGO which discloses each year an urban environment assessment report. This is why it seems urgent to us to react and work to protect, renovate and develop the green spaces of Bishkek. The proposed project aims to protect the unique forest of Bishkek called Karagachevaïa Rocha (“grove of elms”) and to redevelop it to make it an environmental education centre. This center, which would be the first of its kind in Kyrgyzstan, would include in the same place an arboretum, a leisure area as well as an animal park in which various rare or endangered species, present in Kyrgyzstan or in the countries of Central Asia, would be kept in semi-freedom. Karagachevaya Rocha has nearly 123 hectares in total, which is the largest green space in Bishkek and one of the oldest. This adds a symbolic character to the project. (3)

As a solution to the increasing population, pollution and high energy consumption, the municipal government of Shiraz has launched the Green City project in 2008. The main aim of this initiative is to reforest the city's periphery and encourage citizens to plant gardens on rooftops and the private sectors to adhere to the city’s development plan with all construction projects. [1]

Recognising the benefits which urban forests bring to its citizens, Salvador has committed to protecting and restoring the Atlantic Forest, and has developed its own local framework which goes beyond national requirements (Ref. 1). The city has launched several programmes under its 'Salvador, Capital da Mata Atlantica' initiative, which together aim to restore the forest which has "suffered from severe deforestation" (Ref. 1). Included under the umbrella initiative are programmes such as the "'Delivery of trees', recovery of parks and collective planting" (Ref. 4).