Arcachon Basin Wastewater: “We need a real plan, a timetable”

Following the court's suspension of prefectural decrees permitting the discharge of wastewater in exceptional circumstances, the reactions mainly highlight the need for the work.

On Tuesday, May 20, the Bordeaux administrative court suspended the prefectural decrees that modify the Arcachon Basin sanitation system by allowing wastewater to be discharged into the environment and the ocean in exceptional circumstances. This is a victory for the environmental protection association Sepanso, which had requested this suspension in summary proceedings, with the support of other associations. The main argument upheld by the court was the lack of an environmental impact study despite "the gross pollution load in the wastewater."

The president of one of the associations, Jacques Storelli for Ceba (Environmental Coordination of the Arcachon Basin), reacted to this decision. "It was easier to act as if these new decrees only marginally modified the previous ones, in order to avoid the obligation to conduct impact studies or impact analyses, via a real environmental authorization. […] We will now have to demand from Siba (Intercommunal Syndicate of the Arcachon Basin in charge of sanitation) real health and environmental safety before next autumn."

Sepanso's lawyer, François Ruffié, also called for "concrete measures, a timetable, a real plan for Siba following this ruling. Governing means planning, and since 2021 nothing has been done, only announcements and communication. Siba has allowed its network to wither away. The prefecture wanted to give it carte blanche because of the ongoing criminal proceedings. And given the consequences of possible spills, serious studies should have been conducted and the population consulted through a public inquiry."

The same tone is echoed by MP Sophie Panonacle, who declares: "There is an urgent need to undertake work." But also by Green Party representatives Vital Baude and Philippe Gaubert, who are once again calling for "a moratorium on urban development around the Basin," which they believe is the main cause of the flooding in December 2023.

Contacted by Sud Ouest, the prefecture simply said it "takes note." As for the Siba, there was no comment on a court decision, especially since it does not directly concern it. The Syndicate, led by the mayors of the Basin, announced in October 2024 a €120 million five-year work plan for sanitation and stormwater, including €30 million to build a new wastewater treatment plant in the north of the Basin.