Plant-based filter water treatment
In 2024, Ozanam (a housing private company) and the French Development Agency (AFD) formalized a partnership to modernize an ecological wastewater treatment plant in Saint-Joseph, a neighborhood in Fort de France. The project focuses on replacing an outdated 30-year-old installation that no longer meets current standards with a plant-based water filtration system based on the ‘Rhizosph’air’ patent. This innovative treatment process utilizes "filter gardens," which combine mechanical systems, a gravity network, and a phytoremediation approach. The system employs filters made of gravel and the roots of local plants, specifically Strelitzia reginae and Cyperus alternifolius, to naturally and effectively filter wastewater without odor (Refs 2, 3, 4).
The nature-based system purifies wastewater over an area of 2,000 square meters, with a capacity equivalent to serving 900 residents. This approach offers several advantages, including reduced maintenance costs due to its simplicity, decreased energy consumption compared to traditional treatment methods, and improved water quality released back into the environment (Ref 2). Beyond its technical efficiency, the filter gardens enhance biodiversity (Ref 2) by improving the quality of water discharged into the environment and providing habitats for various species. The solution also integrates seamlessly into the landscape, showcasing vibrant flowers native to the area (Ref 1).
Additionally, the project implementers plan to construct a walking path, provide recreational equipment, and install benches to encourage residents to utilize the area as a public green space (Refs 2, 5).
The nature-based system purifies wastewater over an area of 2,000 square meters, with a capacity equivalent to serving 900 residents. This approach offers several advantages, including reduced maintenance costs due to its simplicity, decreased energy consumption compared to traditional treatment methods, and improved water quality released back into the environment (Ref 2). Beyond its technical efficiency, the filter gardens enhance biodiversity (Ref 2) by improving the quality of water discharged into the environment and providing habitats for various species. The solution also integrates seamlessly into the landscape, showcasing vibrant flowers native to the area (Ref 1).
Additionally, the project implementers plan to construct a walking path, provide recreational equipment, and install benches to encourage residents to utilize the area as a public green space (Refs 2, 5).
NatureRx Rain Garden Pilot
The NatureRx Rain Garden Pilot is a community-driven initiative aimed at addressing urban runoff and its associated challenges, implemented by Bí URBAN, a community hub and social enterprise in Dublin focused on urban regeneration. The pilot project developed in Stoneybatter, Dublin involves diverting rainwater from residential rooftops into specially designed rain gardens (1). The area is used as the first trial area by installing around 100 rain gardens (3, 11). Built to fit neatly into available spaces, these self-sustaining planters will filter rainwater through the garden, with overflow pipes in place to prevent flooding during heavy downpours (1).
It is expected that these gardens will transform sterile urban spaces into green areas, enhancing biodiversity, providing habitats for pollinators, and acting as carbon sinks (1,3).
It is expected that these gardens will transform sterile urban spaces into green areas, enhancing biodiversity, providing habitats for pollinators, and acting as carbon sinks (1,3).
The Green City Development
As a solution to the increasing population, pollution and high energy consumption, the municipal government of Shiraz has launched the Green City project in 2008. The main aim of this initiative is to reforest the city's periphery and encourage citizens to plant gardens on rooftops and the private sectors to adhere to the city’s development plan with all construction projects. [1]
Sihlcity Shopping Centre Living Facade
Sihlcity, one of Switzerland's largest shopping malls, is located in the Wiedikon district of Zurich. It was built on the grounds of a former paper mill, Papierfabrik Sihl, near the Sihl River. The Green Wall of the Sihlcity car park is a striking feature of the development at a height of 23 meters and a width of 25.5 meters. The wall is an elegant aesthetic solution to the car park facade, keeps the car park cool during summer, provides insulation in the winter, sound insulation for the busy car park, and an effective deterrent to graffiti. [1]
Green roofs on buses
Green roofs were created on vehicles in the Spanish cities of Barcelona, Girona, Córdoba, Valencia. This initiative is based on the project of Marc Grañén, who developed PhytoKinetic a project for the development of moving gardens. (ref 1) The city of Palma de Mallorca was also considering its introduction as a measure of sustainability. (ref 1) The intervention, however, remained in the pilot stage (ref 1 and 4).
Kopaszi Dam
Before the intervention, the dam was a derelict former industrial and recreational area. (Reference 6) It was transformed into a green recreational park of the southern part of Budapest. 40,000 square metres of grass was laid, 700 trees, 20,000 shrubs and 20,000 perennials were planted. (Reference 4) The park now is a home to a biodiverse population of wild birds. It is one of the few places of the city that have direct connection to the Danube, giving space for strolling, doing sport, playing and relaxing. In 2018, a large-scale development began next to the dam, with the aim of creating a new city center. This would make the park a place for leisure for much greater number of people, but may be detrimental to the ecosystem of the dam. (Reference 6)
