Sustainable water management approach to urban projects

Clichy-Batignolles neighbourhood in Paris

Water is a precious and finite resource, and its efficient use is becoming increasingly crucial as the challenges of climate change and urban growth intensify. Against this backdrop, sustainable water management occupies a central place in discussions on ecological architecture. A number of innovative approaches have emerged to optimize water use, including grey water recycling, rainwater reuse and good urban water management practices. These efforts aim to minimize environmental impacts and ensure more efficient management of this vital resource.

sustainable water management
Water consumption (source: Vizea)
  1. Grey water recycling: Grey water recycling involves collecting, treating and reusing water from household activities, such as sinks, showers and dishwashers, thereby reducing demand for drinking water and cutting water pollution. By reusing grey water for non-potable uses such as watering the garden or flushing the toilet, we reduce the pressure on freshwater resources. However, a filtration system must be installed before any indoor use, the simplest being a tank in which the water must remain for 24 hours.
sustainable water management
Schéma d’utilisation des eaux grises
  1. Rainwater reuse: The use of rainwater in construction offers significant water-saving opportunities. Collected rainwater can be used for both indoor and outdoor purposes, such as flushing toilets, cleaning floors, watering gardens, etc., thereby reducing the demand for potable water. This approach requires collection and treatment systems such as underground tanks or cisterns to guarantee the quality of the reused water.

At city level, a few examples of good water management practices are worth noting:

Lyon

In particular, the Greater Lyon metropolitan area has adopted an ambitious water management policy via a “permeable city” project that is part of the city’s urban policy.

The project aims to address four issues: protecting natural environments and water resources; combating urban heat islands; facilitating the return of nature to the city; and adapting to and reducing vulnerability to flood risks. While the project includes water-saving measures, such as optimizing public watering through the use of connected sensors, it focuses above all on better management of rainwater to limit the city’s impermeability.

Narbonne

Preventing the risk of drought through the use of wastewater treatment for agricultural irrigation is an initiative of the town of Narbonne.

Languedoc-Roussillon is a major wine-growing region, accounting for 30% of French wine production. However, the territory regularly finds itself in a situation of water deficit, which impacts wine production and threatens the sustainability of the activitý.

In this context, the Greater Narbonne metropolis has invested in the Irrialt’eau project: using treated wastewater, analyzed, of good qualitý, and located closé to winegrowing estates, for vine irrigation.

Water can become a central issue in any construction or urban planning project. Optimizing water use throughout a building or even a city not only reduces water consumption volumes, but also saves a precious natural resource for the planet!

Sources :

https://www.build-green.fr/detail-darchitecture-durable-le-recyclage-des-eaux-grises/

http://www.vizea.fr/actualites/actus/1108-la-reutilisation-des-eaux-pluviales-et-des-eaux-grises-dans-le-batiment.html

https://www.demainlaville.com/les-bonnes-pratiques-des-villes-francaises-en-matiere-de-gestion-de-leau/

https://www.cerema.fr/fr/actualites/gestion-integree-eau-milieu-urbain-serie-fiches-du-cerema

https://www.ecohabitation.com/guides/2540/comment-fonctionne-un-systeme-de-recuperation-des-eaux-grises/