Water management (SDG 6)

This NBS deals with the recovery of an avenue (about five thousand five hundred meters in length, it is the longest Portuguese avenue) that connects Porto's City Park with another avenue and the seaside. The NBS is implemented by the municipality of Porto and it indents to create a green corridor between 2 locations: Ribeira de Aldoar and Avenida da Boavista. Previously, work has been done to this NBS, in 2005, but it was not finalized. (1) As of 2019, the Municipality of Porto announced that work will be halted for this NBS (5)

The aim of the project is to restore the near-natural state of the Alster, the neighboring floodplains and side waters and thus support biodiversity, the recreational function of the riversides and promote environmental education (Reference 1). The implementation of the project began in 2012 and is planned to continue until 2021. It’s second phase started in 2018, which focuses on redeveloping the inner-city areas of the Alster. (Reference 8) The developers of the project focus on improving biodiversity and habitats. Recent nature conservation efforts included the installation of bee hotels, installation of gravel depots where fish lay eggs and the building of three fish ladders at the Poppenbüttler, Mellingburger and Wohldorfer locks, so that salmon, sea trout and sticklebacks can migrate there again. (Reference 6) In the future, other biotope structures in the urban river environment are to be improved. The project also provides opportunities for voluntary work and educational field trips for schoolchildren. (Reference 9)

An old hippodrome will be transformed into a natural urban park. "The Metropole of Rouen has launched this reconversion project of in consultation with residents and associations. It is the Mutabilis group that has been chosen to carry out this transformation, the first work of which will begin in 2017. The project, called "Champ Libre", integrates all the components essential to urban life: a place of discovery, nature and innovative agriculture" (Ref. 6).

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.

The project was implemented in the eastern coast of Poland in the Pomeranian Voivodship. A 5.98 km of the current sea coast within the administration of the Maritime Office in Gdynia was secured and fortified until 2015. The purpose of the initiative is to increase the number of marine shore sites restored to a former state by recultivating degraded areas, securing landslides, and securing marine shores from erosion [1].

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].

Paljassaare peninsula hosts the Paljassaare special conservation area and is partly a nature reserve and partly used to accommodate a wastewater treatment facility (ref 3). The leftovers from the treatment facility, processes of urbanisation and cyanobacteria blooms from the Baltic sea are largely influencing the fragile ecosystem of the peninsula through eutrophication. By this, the different cycles and ecosystems (both natural and urban) got more and more intertwined. ‘Perpetuum Mobile’ project aims to rebalance the urban metabolism of Tallinn city with the ecological processes on the Paljassaare peninsula through natural de-eutrophication of the area (ref 4).

In 2017, under a bigger project, the municipality of Sintra started the work for the rehabilitation of an area that included beaches and rivers, such as the Mata river. The NBS solves a problem of accumulation of water and sludge that was unsolved, through the recovery and cleaning of Ribeira da Mata (small river/brook), planting trees and promotion of an improvement in water quality and sand on the beach.
(1)

The Strasbourg Grandeur Nature Plan is engineered by Strasbourg Metropole and is focused on optimising the actions and resources and resources of local authorities in the maintenance of local biodiversity and improving the living environment (Ref. 7). It combines with local associations and citizens through organising interfaces (e.g. workshops, online tools) that allow relevant local authorities to engage with local projects and make interventions on the basis of proposals made by the community. The project aims at improving the maintenance and development of green spaces and biodiversity due to the environmental issues surrounding urban sprawls (Ref. 4).

The main problem of Lake Ülemiste is high phytoplankton biomass, which increases the cost of water treatment (ref 1). Improving the water quality of Lake Ülemiste by biomanipulation has been considered as a management alternative. Lake Ülemiste was bio-remediated after reduction of external loading and the shifts in water quality were studied during the active-phase of the measure. (ref 1). Tallinn obtains 88% of the water it needs from Lake Ülemiste. Pine forest in the sanitary protection zone surrounding Lake Ülemiste offers several ecosystem services that help to improve the quality of the city’s drinking water (ref 4).