MONTOIRE Wastewater Treatment Plant, Montoire-sur-le-Loir, Centre-Val de Loire

The MONTOIRE wastewater treatment plant is located in Montoire-sur-le-Loir, a commune in the Loir-et-Cher department of the Centre-Val de Loire region, France. The plant serves a population of approximately 4,600 residents and is designed to handle a capacity of 9,400 cubic meters per day, with an average discharge volume of 820.63 cubic meters per day. As an advanced treatment facility, MONTOIRE goes beyond the secondary treatment requirements mandated by the EU Urban Waste Water Treatment Directive (91/271/EEC) for agglomerations of this size. The directive requires secondary treatment for populations over 2,000, and advanced (tertiary) treatment is typically implemented in sensitive areas to further reduce nutrients like nitrogen and phosphorus. The plant discharges treated wastewater into the local watershed, which ultimately drains into the Loir River, a tributary of the Sarthe, then the Maine, and finally the Loire River. The Loire is one of France's major rivers, supporting diverse aquatic ecosystems and flowing into the Atlantic Ocean. The advanced treatment helps protect downstream water quality and ecological health.

The plant's treated effluent enters the Loir River, which flows through the Loire Valley before joining the Sarthe and Maine rivers, eventually reaching the Loire estuary and the Bay of Biscay. This watershed supports a variety of fish species, including Atlantic salmon and European eel, and the Loire is known for its migratory fish populations. The advanced treatment reduces nutrient loading, helping to prevent eutrophication in downstream water bodies.