The purer water project did not make the elected officials of Seine-et-Marne salivate. And for
the water union of Ile-de-France (Sedif) which supplies 4 million Ile-de-France residents with drinking water, it’s a cold shower. The Sedif indeed carries the project “Towards a pure water, without limestone and without chlorine” to avoid clogging your kettles. This thanks to
low pressure reverse osmosis (OIBP) which it wishes to experiment on its pilot site in Arvigny, in Savigny-le-Temple. “This process is an improved version of the nanofiltration in place in our Méry-sur-Oise plant”, indicates Sedif. It “consists of filtering the water through a membrane pierced with extremely fine pores which prevents the passage of most molecules except water”, according to a document from the union. Say goodbye to chlorine, limestone and micropollutants.
After a positive opinion from the investigating commissioner in July 2021, Sedif, which brings together 135 municipalities in Ile-de-France, was “very optimistic”. “The prefect of Seine-et-Marne was to give us the environmental authorization for the project in mid-November then it was extended by two months until January 20”, indicates the union. And boom, on January 20, no response from the prefecture, which amounts to an implicit rejection of the authorization. At Sedif, we fall from the clouds. “There was no letter, no email, we did not have the reasoned reasons”, one complains there. There were, however, warning signs such as the unfavorable opinion of the departmental commission for the assessment of health and technological risks (Coderst) of Seine-et-Marne and the equally unfavorable opinion of the Agency’s aid commission of Seine Normandy water (AESN). Moreover, according to the prefecture, this implicit rejection is linked to the “refusal of this project by all the elected officials and associations concerned”.
“A 30% overconsumption of water”, according to an elected representative against the project
This niet therefore delighted the local elected officials, in the first place the mayor of Savigny-le-Temple. For Marie-Line Pichery, it “is not necessarily good in ecological matters”. “For this to work, more water will have to be drawn from the Champigny aquifer, which is already under tension, she denounces. Then, the water is so demineralized that it has to be remineralized with normal water to make it drinkable, resulting in a 30% overconsumption of water. Finally, the substances recovered during filtration, the concentrates, must be discharged into the Seine, which presents an ecological risk. “And what also annoys the mayor is that this process will serve other municipalities than his own. “We defend our territory, she justifies herself. We cannot always have the disadvantages of the desires of development of the small crown ”. Moreover, the town hall refused the building permit necessary for the establishment of the OIBP.
For Sedif, which promises 100 euros in annual savings per household according to a study by Deloitte, these concerns do not hold. “The Arvigny project will only lead to a 10% increase in the pumping of water from the Champigny aquifer, while remaining within the nails of the drawing rights set in 2018”, argues the union. It also ensures, with supporting studies, that the discharge of concentrates “has no environmental impact on the Seine and its ecosystems”. For Sedif, this opposition is above all “political” and linked to a change of majority within the Greater Paris South conurbation, of which Marie-Line Pichery is also vice-president.
A refusal that does not call into question the overall project
This track of a political conflict is not extravagant since the Sedif is chaired by the UDI André Santini and Grand Paris Sud by the PS Michel Bisson. But above all, the agglo is gradually passing
under public control the distribution and sanitation of water previously managed by Suez while Sedif granted a public service delegation to Veolia. Behind the OIBP dossier, there are also two opposing visions of water management.
Despite this failure, Sedif wants to “continue discussions with the actors of the territory” while “reserving the right of administrative appeal” on the prefectural decision. But the union assures us that this refusal does not call into question its project “Towards pure water, without limestone and without chlorine”. And the press release dated January 27 abounds: “Voted by elected officials in December 2021, the 2022-2031 investment plan will devote 800 million euros to the deployment of the OIBP in the three main plants of Sedif, from 2024”.