Water management (SDG 6)

'Groene Mient' (Green Commons) is a citizen initiative that realized an exceptional social-ecological residential project consisting of three housing buildings of energy neutral homes and a 3,500 m2 communal garden (1,6). Storm water is captured from the roofs of the buildings into bioswales, permeable paving is applied, the shared garden is 'eatable' and houses run on sustainable energy (1). The houses do not have a gas connection and have three different sustainable energy systems: heat pump with heat-cold storage, solar boiler or electric heating (6).

The ‘Mountain Forest Initiative’ was launched in 2009 by the Bavarian Ministry of Food, Agriculture and Forestry to restore the protective function of the vulnerable alpine forest in light of climate change, and was ongoing until 2014. To create a general sense of ownership in the process, the Mountain Forest Initiative sought the involvement of different stakeholders at the local level (e.g., private forest owners, land-use related authorities, hunters, nature conservationists, and tourism associations) (Ref. 1).

The Sea Heroes Garden is a community garden that was initiated by citizens on an empty lot with the goal to create a garden in which children can play, fruit and vegetables are grown organically and social activities are organized.(1) In the garden, multiple measures allow for storm water retention and the vegetation provides habitat for a broad variety of species. (5).

The aim of ReWaM was to show ways how different forms of use of water bodies can be reconciled with their protection in order to sustainably maintain the diversity and efficiency of the different water ecosystems. This applies to both rural, suburban and urban regions (ref. 8). Increased sealing of urban surfaces and combined sewer systems for rain- and wastewater pose major challenges for urban water management. Therefore, the university of applied sciences and the city of Münster participated in a research project as one of three pilot cities running from 2015 to 2018 concerning improved rainwater management and the development of respective planning instruments. Several green roofs at the university campus were used as test spaces to explore and monitor rainwater infiltration efficiency and feasible green roof compositions. Also, different permeable surface coatings were tested at the urban depot (Ref. 1 and 4).

The Naturfreibad Haunstetten is an artificially designed bathing lake in the south of Augsburg with a water surface of 9,200 m² and a maximum depth of four meters. After the regeneration of 1,5 hectares of green space surrounding the lake, the baths were reopened in 2010 (Ref. 1).

The new sports campus that has recently been opened in The Hague contains multiple NBS solutions including one of the largest green roofs in the area, permeable paving of parking spots, a creek and trees that can stormwater storage. The building of the sports campus on which the green roof is created is completely CO2 neutral as it runs on solar and geothermal energy. (1,2,5,6,7,8).

The entire neighbourhood area was calling for interventions, considering the conditions of decay of this part of the city. The initiative was requested by the residents of the area, in particular considering the state of plants and trees. What needs to be provided is a new surface of grass to replace the terrain on the ground to avoid problems of flooding and new plantations. The park has an important function in terms of mitigation of anthropogenic pressures, but also in terms of social value for the residents. (Ref.1.)

'Proeftuin Erasmusveld' is a new and sustainable urban residential area in The Hague. It will be a new nature-inclusive, energy-efficient, car-free neighbourhood that is created for plants, animals and people promoting healthy living (1). As of November 2020, The building of the neighbourhood with its unique houses and buildings is still in progress (1).

Currently, the area is an 'experimental area' for all kinds of sustainability initiatives that may be used for the realization of the neighbourhood, including self-sufficient 'tiny houses' and urban farmland (1,2). The ambition for Erasmusveld is to become a leading sustainable neighbourhood with a sustainable water system, the use of sustainable energy and a vegetable garden with high connectedness between citizens (4).

The Natural Park of Augsburg - Western Forests covers a 1,200 square kilometer of the natural area. Founded in 2007, the park aims at preservation and development the natural biotopes in the area. As a supplier of timber, as a guarantor for clean air and pure water, and last but not least for recreation seekers, it is of outstanding importance in Bavarian Swabia (Ref. 1).

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)