Water management (SDG 6)

Since October 2015, the City of Marseille has implemented a vegetation permit called "Visa Vert" (Green Visa), as well as a "Charter for the vegetation of public spaces in Marseille", which allow individuals to install plants in public spaces
while respecting the safety and use of the tracks by other users. Plants, flowers and shrubs can thus contribute to the beautification of the living environment and "bring a bit of nature into the city" (Ref. 1). The charter aims to “ accompany and support initiatives to revegetate the streets and promote collective actions that contribute to embellishing the living environment ”, but also to “ enhance the presence of plants in the city, to respect the public space which belongs to all and thus to improve living together ” (Ref. 5).

This intervention involved the realignment and merging of St. Mary's Way and Livingstone road into "St. Mary's Way Boulevard" of which a sustainable urban drainage (SUD) system is a key component. It consists of 31 large specimen trees that are planted in soil cells. The purpose of this project was to improve pedestrian accessibility, attract net investors, and to enhance the water drainage system (Ref 1).

The biotope Schladitz is the regenerated remains of a former installation for the dehydration of sewage sludge implemented in 1952 by the communal waterworks company which used to pump its sewage sludge into the municipality of Rackwitz North of Leipzig. Upon its termination (1990), the company conducted large regeneration works of the contaminated sites from 1991 until 2011. The area was renaturalized, a biotope was implemented with plants species to retain the toxic substances. Now the area is also used for nature experience, observation and environmental education for children and adults (4, 7).

Allotment gardens have a long tradition in Hannover, with approximately 20.000 gardens stretching around the city as a green belt. In the last decades, some gardens were threatened by disappearance due to investment interests (Reference 1). With the goal to protect these gardens, the city employed a so-called "Kleingartenkonzept" (allotment concept) in 2016 with the help of the association of allotment gardens (Bezirksverband Hannover der Kleingärtner e.V.). The concept aims to keep the number of existing gardens for social and ecological considerations while allowing for new residential investments which is vital for the growing city. (Reference 2).
As part of the concept, extensive inventory examinations were conducted on areas affected by conversion and restructuring, along with the start of implementation of smaller development projects for housing and the creation of replacement gardens in some areas. Because the need for residential spaces has been covered for until the end of 2019, the conversion of allotments for the said land use has been stopped; it will be revisited in 2024. (Reference 2)
To address the problem of future allotment garden losses, gradual elimination of permanent vacancies has started by creating new smaller and more attractive gardens from oversized ones, by improving accessibility and optimizing spaces, and by modernizing allotments (Reference 2).

The Bahlui river was prone to floods especially during spring and autumn and as a result of the fact that for almost 40 years there has been no work for the decolouration and sanitation of the river and the industrial enterprises in the county have discharged polluting substances in water (mainly nitrogen and phosphates), Bahlu River has become a polluted river. In addition, some citizens of Iaşi have discarded waste in its bed (especially in peripheral areas). In 2011, a larger project funded by the EU, implemented the regularization of the river. (1)

Renovations were conducted on Bayard Street, an artery in Toulouse, between 2016 and 2017 Rue Bayard, in anticipation of the arrival in 2024 of a new metro station and the complete overhaul of the Matabiau district (Ref. 10). Renovations included introducing vegetation to the commercial street leading to Matabiau station (Ref. 5) and its newly renovated city centre via planting 81 trees (44 pear trees and 37 hazel trees of Byzantium) (Ref. 2). Furniture was also added and sidewalks were widened for greater pedestrian comfort (Ref. 2).

The former site of the Krupp cast steel factory was transformed into a 230 hectares green belt stretching from the city
center to the district of Altendorf, while the adjacent industrial wasteland was turned into an 11 hectares add-on to the Krupp Park (Ref. 1). The landscape vision "Freiraum creates urban space", in which the Krupp Park is a building block, is a comprehensive strategic approach that aims to gradually build up new urban landscape structures and to create diverse qualities of location for different urban uses" (Ref. 9).

The office building of the Nord/LB Bank that was built in 2002 became a landmark of Hannover. A huge proportion of the building is naturally ventilated. The interior is designed with progressive energy concept with superstructure exposed and windows that provide ventilation. The building is also protected from noise and vehicle emissions through the areas of double façade, which also serves as a duct transferring clean air from the central courtyard to the individual offices. The reflection of daylight is increased through the large areas of water in the courtyard which also contributes towards a beneficial microclimate. The building is also equipped with generous roof gardens which not only provides aesthetic benefits but also improves the general climate for the occupants, and collects rainwater for irrigation and use within the building.
The building is owned by Norddeutshce Landesbank and was designed by BEHNISCH, BEHNISCH & PARTNER (Reference 2).

Numerous developments have been carried out at the National Veterinary School of Toulouse's (ENVT) green campus to make the site more conducive to the maintenance and development of biodiversity as result of the school's "VERT VET" (GREEN VET) club (Ref. 2). The green changes began as a result of the school's 2008 sustainable development policy (Ref. 1). Among its many functions and activities, the policy helped raise awareness, clean ponds, and a well, construct a vegetable garden and make beehives and bird nest boxes in the campus's two classified forests (Ref. 3).

The Urban Environment Observatory Building (OMAU) was built in Malaga as part of the URB-AL 1998 project, it is a construction planned for environmental conservation and includes an ecological cover for the use of rain water in the supply to the structure's watering system. (Ref 2, 3)