Sustainable urban runoff treatment using geosynthetic infiltration
- Giovanna Winetzki
- Jan 16
- 3 min read
Overview
The redevelopment of Rue Ampère in the Chapotin Nord Business Park presented a critical opportunity to implement a sustainable stormwater infiltration and depollution solution in an urban environment characterized by high impermeability and significant heavy vehicle traffic. Situated in a zone experiencing daily passage of approximately 200 heavy trucks and subject to stringent topographical constraints, the site posed numerous technical challenges for traditional stormwater management strategies. The primary goal was to address the lack of gravitational connection to the existing stormwater network while ensuring environmental compliance and long-term performance. To meet these objectives, the project stakeholders selected the OSMORIA Geoclean depolluting aquatextile as a core geosynthetic solution, enabling decentralized hydrocarbon remediation directly at the infiltration source. This case study outlines the technical and environmental rationale for this choice, as well as the implementation process and performance outcomes.
Challenge
The principal challenge faced during the rehabilitation of Rue Ampère stemmed from the inability to connect the roadway to the existing stormwater drainage system due to adverse altimetric conditions, compelling the engineering team to evaluate a range of alternative solutions. Complicating matters further was the environmental requirement to treat runoff water potentially contaminated with hydrocarbons and polycyclic aromatic hydrocarbons (PAHs), common pollutants associated with vehicular traffic.
Although the local subsoil, composed of highly permeable quarry pebbles (10⁻⁴ m/s), offered a favorable context for infiltration-based solutions, the natural advantage of the site was offset by the operational requirements associated with treating polluted runoff from this high-traffic area (200 heavy trucks per day). Several engineering solutions were explored and subsequently discarded for technical, financial, and operational reasons. These included:
Installation of a pumping station for runoff water conveyance,
Deployment of an extensive buried drainage network with 11 collection grates, 400 m of piping, a large-volume infiltration well, and a high-capacity hydrocarbon separator
Distributed infiltration pits connected to each collection grate or pair of grates, each coupled with an oil-water separator.
Given the limitations of these conventional approaches, a more streamlined, low-maintenance, and environmentally effective solution was preferred: OSMORIA Geoclean pollution-reducing aquatextile, which purifies runoff water as it infiltrates.
Solution
The solution chosen was to integrate OSMORIA Geoclean within a network of linear infiltration trenches built along Ampère Street. This innovative solution offers both excellent permeability and optimizes the processes of hydrocarbon fixation and biodegradation, enabling the project manager to meet hydraulic, geotechnical, and environmental performance criteria while adhering to an economical design.
Each infiltration trench measured 17 meters in length with cross-sectional dimensions of 1.5 meters by 2 meters and was filled with appropriately sized quarry pebbles. Depending on the design configuration, trenches were connected to one or two surface collection grates, delivering a useful volume of either 13 m³ or 26 m³ per unit. Polluted runoff water is directed to the trenches through perforated pipes, where it infiltrates through the aquatextile, which traps hydrocarbons and PAHs as the water passes through.
The OSMORIA Geoclean aquatextile functions by physically retaining hydrocarbons and PAHs as water infiltrates through its structure. Its performance is enhanced by the integration of a natural growth activator deposited on the textile’s continuous blue filaments. This biological stimulant accelerates the colonization of the textile by native microorganisms already present in the soil and water, fostering the development of a resilient biofilm. These microbial populations actively biodegrade the hydrocarbons fixed within the textile matrix, thereby maintaining its retention capacity and enabling continuous, long-term depollution without the need for mechanical intervention or replacement.
Tests conducted by independent laboratories measured residual hydrocarbon concentrations in water after passing through the infiltration structure equipped with aquatextile at less than 0.7 mg/L. This value is below the regulatory thresholds of 5 mg/L (based on the performance of hydrocarbon separators) and confirms the effectiveness of the solution.
Ultimately, the use of OSMORIA Geoclean represents a paradigm shift in urban stormwater management, combining various environmental benefits: stormwater pollution control at source, reduced land use, and better protection of soil, groundwater, and biodiversity.
From a cost-benefit perspective, the depolluting aquatextile offers a significant economic alternative, not only in financial terms but also in terms of logistics. By eliminating the need for heavy civil engineering work (dimensioning and connection of networks and frequent maintenance, extensive pipes, use of hydrocarbon separators), operating expenses and investment, the project management team was able to provide an autonomous, sustainable, and reproducible infrastructure solution for treating urban stormwater pollution in environments with challenging topography.
