Landscape swales equipped with OSMORIA aquatextiles as a sustainable solution for stormwater management in coastal areas
- 2 days ago
- 2 min read
Overview
As part of a sustainable redevelopment plan for the seaside resort of Moliets-et-Maâ in southwest France, the municipality initiated a large-scale project to transform the central beach area and surrounding public spaces into a greener, more pedestrian-friendly environment. Covering 35,000 m², the project reflects a broader commitment to environmental resilience, focusing on reducing surface sealing, improving water quality, and promoting active mobility.
To support these goals, 930 m² of OSMORIA® Geoclean® Origin were installed in landscaped swales (noues paysagères) to manage runoff from nearby traffic areas and parking lots, which are particularly busy during the summer season.
Challenge
Runoff from vehicle circulation areas often carries pollutants such as hydrocarbons (HCs) and polycyclic aromatic hydrocarbons (PAHs), substances harmful to aquatic and coastal ecosystems. In Moliets-et-Maâ, managing these contaminants presented a technical challenge due to fluctuating traffic volumes, highly permeable sandy soils, and the need to maintain visual and ecological harmony in a sensitive coastal environment.
The municipality required a stormwater treatment solution that would:
Ensure irreversible fixation of hydrocarbons to prevent re-release into the environment.
Function efficiently regardless of local soil quality or weather conditions.
Integrate naturally within the landscape design of the redeveloped zone.
An effective and sustainable solution to limit maintenance costs
Solution
The design team from SCE Bayonne, in partnership with Eiffage Route, selected OSMORIA for the landscaped swales. This highly permeable technical textile was chosen for its proven ability to retain and biodegrade hydrocarbons within runoff water.
OSMORIA operates through a dual mechanism:
Fixation: Pollutants are captured and immobilized within the textile’s structure, preventing any subsequent release.
Biodegradation: Indigenous microorganisms (local microbiota) present in the soil that have colonized the aquatextile actively biodegrade hydrocarbons and PAHs, ensuring long-term elimination of pollutants without clogging and in a completely autonomous manner.
This natural process continues to perform even under variable hydrological conditions, maintaining efficiency in both dry and saturated environments. The system’s performance has been verified on the textile alone, confirming its ability to treat runoff independently of soil quality or surrounding materials.
Outcome
The use of OSMORIA contributed to the municipality’s wider objective of reducing impermeable surfaces, nearly 7,000 m² were re-vegetated or restored, and enhancing stormwater quality before it re-enters the local environment. The landscaped swales now serve as both functional and aesthetic features, supporting biodiversity while discreetly filtering pollutants from urban runoff.
This project marks an important step toward a resilient, low-impact coastal infrastructure that aligns with France’s broader “ADS sustainable development” framework.
