Reduce the impacts of climate risks events on urban places and communities

Droughts are one of the most serious threats to water availability, food security, and local livelihoods in the semi-arid areas of Tanzania. Drought condition is coupled with a rainfall deficit and poor rainfall distribution. In Tanzania, drought conditions are observed more frequently in the country's northern and central portions (Arusha, Manyara, Shinyanga, Simiyu, and Dodoma). This consideration was paramount when in 2019, the Municipality of Dodoma, alongside ICLEI - Local Governments for Sustainability, erected a new garden positioned in a square in the centre of the city. Nyerere Square in Dodoma used to be an open, concrete space with the statue of Julius Kambarage Nyerere the only attraction apart from the informal traders scattered along the main walkway. Nyerere is the former prime minister and president of Tanganyika, as Tanzania was known before, and subsequently president of Tanzania. It would prove challenging to sustain such an initiative in this drought-prone city. To ensure the park outlived the project, the team installed a greywater system to irrigate the new garden and ensure there was always sufficient water to help the plants flourish. (1,2,3)

South Africa is struggling to provide services to the millions of poor people migrating to the major centres and living in informal settlements (shanty towns), built on land that was formerly used for agriculture or pasturage. Vegetation is sparse and the open spaces between the houses are generally of beaten earth. These areas face persistent challenges that undermine health and everyday well-being and increased disaster risk due to their poor design and lack of green infrastructure. Moreover, informal settlements are very vulnerable to flooding events, which affect the quality of life of the people living in them. Such a case is Diepsloot, a settlement in Johannesburg, where a team of researchers implemented a sustainable urban drainage system with the purpose of alleviating poor water infrastructure and addressing issues related to land erosion and environmental degradation. This research has been benefiting from the support of the local population through adaptive co-management and joint implementation of the intervention. (1,2)

The project focuses on encouraging residents of Rio de Janerio's Arará favela to install green roofs on their homes, primarily to reduce the urban heat island effect but also to harness the broader social, environmental, and economic benefits which green roofs can provide, "...from providing thermal protection and improving air quality to mitigating stormwater runoff pollution and saving costs for both residents and cities" (Refs. 2 & 3). The individual behind the project, Luis Cassiano Silva, further hopes that introduction of green roofs into the favela which help to improve residents’ quality of life and "describes the emotional benefits of incorporating green space into the favela landscape" (Ref. 2).

In order to promote Urban and Periurban Agriculture and Forestry (UPAF) as a municipal strategy to deal with negative climate change effects, Bobo-Dioulasso local authorities have identified, using a participatory approach, city greenways as experimentation sites for local climate solutions. The intervention consists in transforming vacant land belonging to the city into green corridors (greenways) through market gardens and forestry, retaining the benefits of urban agriculture. Urban agriculture, when planned and managed properly, can contribute to climate change mitigation efforts by lowering the ecological footprint associated with food production. At the same time, urban agriculture can enhance climate change adaptation efforts by increasing vegetation cover and reducing surface water run-off, while at the same time conserving biodiversity. (1,2,3,4)

The Chulalongkorn University (CU) Centenary Park was created to provide a green space for the city and celebrate Chulalongkorn University’s 100th anniversary. Located in the centre of shopping and commerce, the park is designed as a multi-functional “urban forest”, which serves as an oasis for the residents and visitors of Bangkok, who can spend quality leisure time in a lush and pleasant environment. The park includes constructed wetlands with rain gardens, retention ponds, an underground water drainage system and green roof areas. Opened in 2017, Chulalongkorn Centenary Park is the first critical piece of green infrastructure in Bangkok to mitigate detrimental ecological issues and disaster risk reduction. Unlike other public parks around the city, this one is the first in Thailand to demonstrate how a park can help reduce urban flood risks and help the city confront climate change, all while offering city dwellers a place to reconnect with nature. Designed with various ecological design components, the park reminds the city of ways to live with water rather than fear it. [1, 2, 4]

The Rioni River basin is the second largest in Georgia, originating in the Greater Caucasus range and flowing into the Black Sea, traversing the town of Samtredia. Samtredia has been affected directly on many occasions by floods that have become a current occurrence in the Rioni River basin as of late. The underlying causes of vulnerability to climate change in the Rioni basin can be categorised into 1) physical factors –direct manifestations of climate change, 2) factors caused by anthropogenic intervention – those related to the harmful ways in which humans have and continue to interact with the environment which has exacerbated vulnerability and 3) Institutional factors – related to the legislative/regulatory barriers placed by government and other institutions, as well as limited capacity (human and resources) to manage climate change vulnerability. Flooding has been harmful not only to the local population but also to the biodiversity of the area, which suffered losses and an ecological imbalance and a disruption in the habitat patterns of local fauna. Many of these issues became the focal point of an activity developed by the Adaptation Fund alongside the Georgian government as early as 2012. The intervention stretched for 4 years and involved several localities in the Rioni River Basin, including Samtredia municipality, consisting of creating bank terracing, vegetative buffers, and tree revetments in order to address floods related to the Rioni River basin and the localities it traverses. (1,2)

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 construction of "the biggest vertical garden in Uruguay" was completed in 2014 (Ref. 1). The vertical garden has an area of 300m2 and contains over 6,000 plants, of which most are endemic, comprising 35 species and 10 different families (Ref. 2). In addition to being aesthetically pleasing, the garden is intended to reduce temperature, produce oxygen and offset greenhouse gas emissions. It is thought to "contribute...to the filtration of approximately 165 tons of gases per year and [be] capable of producing the necessary oxygen for 255 people, in addition to trapping 130 kilos of dust" (Refs. 2 & 3).

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).