Question 13573 — water and sanitation

Summary

Ms. Ersilia Soudais alerts the Minister of Ecological Transition, Biodiversity and International Negotiations on Climate and Nature about the vulnerability of drinking water production plants to the risk of a hundred-year flood and particularly the Annet-sur-Marne plant, located in her constituency of Seine-et-Marne. The Annet-sur-Marne factory, owned by Veolia which operates it, has been located since January 2026 under the shared governance of the SEM “Water, Energy and Solutions”. It constitutes the main water lung of Marne-la-Vallée and serves more than 600,000 inhabitants, including the Paris-Charles-de-Gaulle and Marne-la-Vallée airport basins. However, mapping from the Paris Region Institute reveals that this critical infrastructure is located on the edge of the Marne, in an area where flood zones (direct submergence) coexist with areas of network fragility (indirect vulnerability through failure of dependent infrastructures). This double exposure raises questions about the resilience of the drinking water supply in the event of a major flood. For comparison, during the flood of 1910, four factories in the Paris suburbs were flooded (Nogent-sur-Marne, Neuilly-sur-Marne, Choisy-le-Roi, Suresnes), forcing the population to obtain unfiltered water then by makeshift means. Today, with 600,000 people depending on a single factory on the banks of the Marne, that of Annet-sur-Marne, the consequences of its decommissioning would be considerably more serious. The OECD has also warned of this risk: a 100-year flood could affect 5 million subscribers on the outskirts of Paris with outages “for indefinite periods of time”. ". Seine-et-Marne participated, from October 13 to 17, 2025, in the HYDROS 25 exercise. This exercise aimed to simulate a major flood of the Seine, the Marne and their tributaries in Île-de-France. The strategic objective of this exercise is to strengthen the region's resilience in the face of a major risk and to better protect and inform Ile-de-France residents, which raises the importance of anticipating relative vulnerability issues. to this infrastructure and potential needs in terms of physical protection measures (elevation, dikes, electrical protection, generators). This also reveals the need for a business continuity plan to ensure the supply of drinking water to the 600,000 inhabitants, in the event of a plant shutdown. This is why she asks him what measures are planned by the Government concerning the factory of Annet-sur-Marne, in terms of risk assessment, protection measures as well as an emergency continuity plan in the event of a 100-year flood.

Machine translation from French. The official text remains authoritative.

Timeline

No timeline events have been ingested for this record yet.

Votes

No vote records are attached yet.

Versions

No version snapshots stored. Document URLs remain at the source.

Documents

No documents linked.

Sponsors

No sponsors or actors listed by the source.

Related records

No cross-record relationships stored yet.