Rapid emergency wastewater treatment solution for the city of Pornic

Project's context & challenges

The coastal town of Pornic in France experienced extreme wastewater overflow following periods of heavy rainfall. The Salettes wastewater treatment plant (WWTP), designed for a capacity of 8,000 m³/day, received peak inflows of up to 22,000 m³/day. This overload resulted in untreated wastewater being discharged into the sea, causing shellfish contamination and posing a serious economic threat to the region’s oyster farming industry.

Local authorities required an urgent and reliable temporary treatment solution capable of rapidly increasing treatment capacity while ensuring environmental protection and regulatory compliance during peak hydraulic loads and ongoing infrastructure upgrades.

Customer benefits

Rapid emergency deployment

A fully operational mobile treatment station was deployed within days, minimizing environmental risks.

Environmental protection and regulatory compliance

The solution prevents wastewater overflow and supports compliance with strict “zero overflow” obligations during heavy rainfall events.

Flexible and modular installation

Plug-and-play configuration enabled assembly within 15 days and adaptable operation during varying flow conditions.

Operational continuity during renovation

The temporary installation ensures uninterrupted wastewater treatment while major WWTP upgrades are carried out.

Water reuse opportunities

Part of the treated effluent is reused for irrigation of public green areas, including parks, gardens, and a golf course.

Solution

Mobile Water Solutions deployed a complete temporary wastewater treatment installation to provide an additional 3,000 m³/day treatment capacity.

The mobile plug-and-play system was rapidly installed and commissioned, enabling immediate mitigation of overflow risks. Wastewater undergoes flotation, filtration, and UV disinfection to ensure safe discharge or reuse applications such as irrigation.

The flexible and modular setup allows continuous operation during heavy rainfall events while supporting the continuity of wastewater treatment services throughout major WWTP renovation works.