Water management (SDG 6)

Due to human interventions into the natural river flow with dykes, drainage of agricultural and grassland or cutting off its water bodies, the wetland Elster-Luppe had lost its groundwater base which decreased its biodiversity. With the support of the regional biodiversity fund and building on previous efforts, the city of Leipzig, together with partners such as the NABU Sachsen and research institutions, has revitalized, renaturalized and connected the water bodies of Leipzig's North-Western wetlands to one continuous watercourse since 2012. Its objective is restoring its ecosystem functions and increasing awareness for the importance of wetlands (4, 5).

In 2010, rehabilitation works on the Huveaune riverbanks, in the city of Marseille, were carried out by volunteers from three associations: Rives & Cultures, Planète Sciences Méditerranée, and Hunamar. Work included clearing, revegetation, and maintenance of riverbanks (Ref. 1). Since this initiative took place, the l'Huveaune Watershed Union has been formed and taken steps to formalize the rehabilitation of the Huveaune riverbanks (Ref. 2, 3, and 4).

From 2009 to 2018, a green wall including 1,700 mediterranean perennials (agapanthus, valerian, fern) fed by a water-saving watering system was in place in a heavily frequented part of Marseille (Ref. 3, slide 4). JC Decaux Advertising offered the 70 m² of space for advertising display around the green wall. The project was abandoned in 2018 when the vegetation was completely removed to allow for advertisements to take up the entire surface of the wall (Ref. 1).

The development of the sustainable district of the Haute Deûle River Banks, associated to Euratechnologies TIC center, leans on recognition of water as an element of its foundation. The current innovation is about the water garden. It is a part of the bigger project, building an eco-district on the banks of the Haute Deule river. The water garden, which plays the role of storage (stormwater) and of phytoremediator, evolves with the rhythm of rain and becomes the emblematic place for this work with water. Its vegetation improves every year and the natural seeds of young willow trees contribute to the establishment of a dynamic ecosystem (Ref 1).

The river Emscher is the symbol of one of the internationally most renowned industrial regions: the Ruhr area with its 5 million inhabitants and an important location of key industries such as steel, chemical, and materials industry. The revitalisation of the Emscher over the last 20 years marks a new phase in the region‘s history and is an impressive example of ecological and socio-economic transformation affecting all aspects of life along the river (Ref. 1).

The aim of the project is to implement a sustainable rainwater management in Hamburg that is adjusted to the heavy rainfalls attributed to global climate change. The project involves the analysis of pilot projects, including GIS-based analysis and the development of the city's rainwater structure plan 2030, Strukturplan Regenwasser 2030, (Reference 1) that will serve as a basis for the Integrated RainWater Management (IRWM) in Hamburg (Reference 5).

EPAEM (Euromediterranean public development establishment) launched the development a new park of 14 hectares. Located in former industrial area at the gates of the northern districts of Marseille, it is considered to be one of the poorest districts in France (Ref. 1). The planned park Aygalades is divided into two parts: the southern part of 4 hectares called Bougainville Park and the northern part of 10 hectares which runs along the Aygalades river (Ref. 1). Development work on Bougainville Park is set to begin in September 2020 with completion in 2023 (Ref. 12). The park is described as "the first step of a large project to restore a highly degraded industrial site" (Ref. 12).

The ‘University Park Essen’ is developed on a former railway site in the inner city of Essen, that had been a wasteland for almost 30 years. By revitalizing this about the 13-hectare large plot, an urban green quarter for residential and commercial use is created. The centricity of the park within the new quarter between the city center, shopping mall Limbecker Square and the university campus is the first visible component of the development and therefore shapes the new identity of the quarter (Ref. 4).

A new lake with green banks was built in the district of Altenhof in Essen in order to improve the quality of life in the neighborhood, create new recreational facilities and prolong the existing transport and green infrastructural developments in Essen. The water is supplied to the lake by means of groundwater from a separate well, as well as rainwater from the surfaces of neighboring roofs (Ref. 1).

Citizen Farm was a start-up founded by Pierre Osswald (Ref. 3). The project began with an experimental urban farm in a vegetable garden of Raymond 6. The ozarium farm (a vegetable aquarium) uses a technique called aquaponia (Ref. 5). This technique grows all kinds of plants and vegetables indoors in an entirely natural way. Fertilizer or watering are not needed. Plants feed on the nutrients in the aquarium: water and fish discharges. In return, they purify and oxygenate fish water. It is an ecological and educational innovation which is surfacing as an "eco-responsible" trend. (Ref. 1, 2). The Citizen farm initative was ended in 2018 due to financial difficulties (Ref. 35).