Increased protection against flooding

This NBS was implemented in 2012 in order to conserve the biodiversity in the natural protected area of the Cilieni Pond and in order to ensure the sustainable development of protected species. The Pond was declared a protected area and covers ​​47 hectares. First an evaluation plan of the current situation was created, followed by a management plan. Inventory of the flora and fauna was conducted and protection methods were implemented: cleaning the area and educating the citizens that have a daily contact with the pond. (1)

The Sand Motor is a hook-shaped peninsula that is artificially created at the coast near The Hague in order to protect the coast on the long-term. Not only provides the Sand Motor coastal protection, but it also allows for new forms of recreation and supports biodiversity as it creates habitat and allows for more varieties of species to live in the area. The Sand Motor is a unique pilot project in coastal management and follows the principle of 'building with nature' (1).

The Green Grid aimed to link urban and rural neighborhoods with a network of quality green spaces and corridors of landscape, recreational and ecological value. The aim was to achieve the added benefits by managing open space resources as a set of linkable sites rather than in isolation. It was a planning intervention that was focused on connecting a high quality, functional green space network (Ref 1). The intervention was part of "Greening the Gateway Kent & Medway" (Ref 2).

The Natural Park of Collserola (about 8,000 ha) is a forested area in the hilly Northern fringes of Barcelona. Since 1987, Collserola has been managed under a special protection plan and forms part of the European FEDENATUR network that aims at protected fragile peri-urban ecosystem for both their social and ecological functions. The park is jointly managed by a consortium including the Catalan government (Generalitat de Catalunya), the Barcelona Provincial Council (Diputació de Barcelona), the Metropolitan Area of Barcelona (AMB) as well as all adjacent municipalities (Ref 1).

Joan Reventós Park is a public park of about two hectares in Barcelona. It was opened in May 2009. The park is located within the catchment area of “Riera de les Monges” watercourse. For this reason, a sustainable drainage and sewer system (SUDS) was created in case of heavy rainfall, also harboring a flood area that prevents overflows (Ref. 1). This 20,091 square meter forest area has been converted into a recreational space for the local neighborhood and a playground, as well as a connecting corridor between the school zones and the center of the neighborhood (Ref. 3)

The Barcelona Green Infrastructure and Biodiversity Plan 2020 includes the development of several urban green corridors to increase ecological and social connectivity within the city. The green corridor of Passeig de Sant Joan is one of the first of these corridors implemented. The project consisted of the renovation of the promenade through tree and shrub planting and permeable green pavement installation, creating a green boulevard that benefits pedestrians and extend the urban green spaces, which gave new life to the neighborhood and allowed the expansion of small businesses and tourism (Ref 1).

The Molenvlietpark is a large park in the Viletzoom area of The Hague which will serve as an ecological corridor and stormwater storage. Beside flowery grasslands, the park has several interconnected ponds serving as water storing facilities that can temporarily collect a large amount of water during heavy rainfall. The green and blue areas with diverse vegetation provide habitat for a large variety of species and a fish spawning ground supporting biodiversity (1,5,6,7). It will also include paths for cyclists and pedestrians. (1) The first phase of the park construction has been completed, while the second phase is planned to be executed in 2021-2022.

After 3 years of works, in 2020 the city of Gdynia revitalized one of its largest parks with a panoramic view on the rest of the city. Planned activities had included new greenery (suitable for the local climate conditions), rebuilding vegetation, creation of the educational paths, building water playground facilities and a sensory garden, open-air gyms and improved infrastructure for the disabled [1,2,3]. The final project focused on the renovation of the amphitheatre and the drainage system underground. Residents have been enjoying the park since June 2020 [7].

The project is a part of a larger initiative to revitalize this neglected district of the city and involves redevelopment and expansion of rain drainage system in Gdynia Chylonia. It resulted in the construction of rainwater retention systems and rainwater sewage systems with safe rainwater discharge to the Chylonka River. The aim of the wider initiative is to ensure a more decent standard of living and social cohesion by revitalizing the neglected areas of Gdynia [1,2,4].

The Danube Eco-District project is Strasbourg's first eco-districy and is based on previous experimental designs in sustainable urban living (Ref. 27, 30). It is situated at the heart of the axis Deux Rives, and is thus a strategic point of the large Franco-German Deux Rives project (Ref. 28). The district will have the capacity for 20,000 residents, and will include green spaces, green roofs, insect hotels (Ref. 1), various water management facilities (ditches, swales... etc.), and composting facilities (Ref. 4). The project aims to improve biodiversity, social equality, ecology, reduce urban heating, and promote sustainable consumption (Ref. 30).