How did norovirus, the gastroenteritis virus, end up in oysters from the Arcachon basin just days before the end-of-year holidays, prompting the authorities to take them? an order temporarily banning their marketing ? The measure has been in effect since December 27th and could be repealed January 19th “assuming the analyzes are favorable”has already resulted in a loss of sales of more than 7 million euros for oyster farmers in the industry.

Two On December 29, the Water Protection Association of the Arcachon Basin (Adeba) and its president Thierry Lafon filed a lawsuit against the Intermunicipal Union of the Arcachon Basin (SIBA), which has managed the Arcachon Basin for sixty years. Water treatment in this area of ​​the Gironde. Two other environmental associations, the Society for the Study, Protection and Development of Nature in the Southwest of the Gironde (Sepanso) and the Environmental Coordination of the Arcachon Basin (CEBA), as well as individual oyster farmers are also studying the possibility of filing a complaint.

The reason for this contamination of the oysters: a dire situation between a gastroenteritis epidemic and a heavy and persistent rain episode lasting several days. It fell between October 26th and December 13th 70 centimeters of water in the Gironde, which corresponds to the annual rainfall. The retention basins that were supposed to hold back this rainwater were not sufficient to prevent the runoff.

“An open sewer”

The wastewater collectors around the basin also proved inadequate to absorb all the water. “It was an open sewer that flowed for days and days, even weeks. This would be one of the causes, there are undoubtedly others around the basin and we need to investigate there. Hence the purpose of the complaint and the investigation, which will allow us to know exactly what happened. explains Joël Mellet from Sepanso Gironde.

The plaintiffs blame the rampant urbanization of the Arcachon Basin. They believe that SIBA is torn between two tasks: on the one hand, collecting and treating wastewater and, on the other, promoting tourism in the region. SIBA was founded in 1964 with the aim of protecting the waterway and its oyster farmers. It is administered by elected officials of the municipalities of the Arcachon Basin.

“SIBA is faced with a certain schizophrenia, regrets Thierry Lafon. There is its original DNA and the fact that it is in the hands of people who only see through the evolution. We find ourselves in a logic of concreting, ignoring the fundamental things to protect this territory and in particular the issue of rainwater, ignoring the fact that we have a soil saturated with water. » The president of the SIBA, the mayor of Arcachon, Yves Foulon (Les Républicains), and its general director, Sabine Jeandenand, did not respond to requests from World.