Improved stormwater management

The medieval style Shared Garden Of Sainte-Madeleine Place development - situated in between two nearby schools - in 2009 was quickly claimed by the Association des Habitants Bourse Austerlitz Krutenau (Association of Inhabitants Bourse-Austerlitz-Krutenau) (AHBAK) neighborhood association because of its historic environment. The project turned the space into a shared garden, involving a collective composting area for organic waste, installing a rainwater recuperator, and planting local plant and vegetable species and new trees (Ref. 1, 2, 3).

This NBS is Porto’s largest green roof, sometimes referred as the "Fifth Façade Urban Rooftop Garden", the "Olive Trees Garden" is an oasis of 50 olive trees and lush grass on top of a semi-open gallery of shops, restaurants, and cafés with an underground parking garage.
It’s an urban park escape for city workers, tourists, and university students. Located on top of "Praça de Lisboa" (Lisbon square), this is a fantastic concept of urban planning done right: green space co-existing with commerce and vehicles below street level. This project was completed in 2013 as an effort to improve an area in decline in the middle of the cultural centre of Porto by creating a green space for the community (Ref. 1, 2).

The water treatment station in Marquette-lez-Lille had a makeover in September 2014. The facility was renovated and rebuilt with cutting-edge technologies and included a new energy production unit. The plant serves 37 municipalities with treated water. The renovation project enabled the station to be integrated into an urban environment. Almost 17 acres have been transformed into a wetland with the planting of more than 20,000 trees and shrubbery. Encircled by a high-speed road, the Deûle canal, a forest and homes, this classified site is marked by exceptional biodiversity. The Marquette station is recognized as a leader in its industry and was nominated by Global Water Intelligence (GWI) as one of the four projects of the year worldwide for 2014 (Ref 1).

While Hamburg has already had an impressive green infrastructure, it is now (since 2013) implementing an interconnected green network that will cover the 40 % of its area and support commuting by bicycle, recreation and climate change resilience. The project is planned to be completed by 2034. (Reference 9) The project aims to connect the two green belts, parks, recreational areas, cemeteries and animal habitats to each other with green paths and with the already existing “green axes” leading from the agglomeration to the urban core. The green network could not only absorb more CO2 but also prevent flooding by soaking up an increased amount of rain- and seawater caused by storms. (Reference 1, 2). An extensive network of cycle paths is also being built as part of the project. (Reference 2)

In 2014, the Marseille Provence Métropole Urban Community commissioned five new stormwater retention basins in order to preserve the quality of coastal waters and reduce the risk of flooding (Ref. 4). In the past, in the event of severe thunderstorms the sewage networks became saturated and a portion of the water was then directly discharged into the sea without going through the sewage treatment plants (Ref. 1). This is seen as "one of the most important documents of recent years in terms of environmental protection. It foresees in the next 5 years, 185 million euros of major works" (Ref. 1).

The scheme was designed to manage surface water runoff from a 1 in 30 year event and to always intercept and treat the, often more polluted, first flush of highway runoff (ref. 1). A total of 21 linear rain gardens (total of 148m2) were constructed within the grass verge, allowing for the constraints of access, below-ground services, street furniture and trees. The rain gardens utilise a combination of clean stone aggregate and proprietary units to create void space beneath a planted topsoil layer. They were designed to capture runoff from 5500 m2 of highway from a total surface area of 7100 m2 (ref. 1).

Kronsberg was built as a model district of sustainable urban development for the EXPO 2000, which motto was 'Humankind-Nature-Technology'. In the previously intensively farmed area, 3200 new dwelling unit was built. Among other sustainable technologies, the planners of the district developed a quasi-natural drainage system that aimed to provide the municipalities a sustainable alternative for traditional drainage (Reference 1, 2).

20 years after planning started in 1992, EXPO district of Kronsberg has proven its viability in terms of sustainable urban development and provided important foundations for advanced urban planning of new buildings in Hannover and elsewhere. The project was showcased in the ‘Crystal’ exhibition pavilion in London as a global standard for integrated construction. The ‘World Cities Summit 2012’ in Singapore also paid tribute to the residential area as one of the world’s hundred most innovative infrastructure projects (Reference 1, 2013).

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).