LA SAGNE Wastewater Treatment Plant, La Sagne, Neuchâtel, Switzerland

LA SAGNE is a wastewater treatment plant located in Les Coeudres, La Sagne, in the canton of Neuchâtel, Switzerland. It serves a small population of 473 residents, reflecting its role in a rural or peri-urban community. The plant is part of Switzerland's well-regulated water infrastructure, which emphasizes high treatment standards to protect the country's lakes and rivers. The plant employs advanced treatment processes, which go beyond secondary treatment to remove nutrients and other pollutants. With a designed capacity of 975 m³/day and an actual discharge volume of 214.71 m³/day, the plant operates well below its capacity, indicating room for future growth or seasonal variations. Swiss regulations under the Federal Water Protection Act require stringent effluent quality, especially for plants discharging into sensitive water bodies. The treated effluent from LA SAGNE likely flows into local streams that drain into the Areuse River, which eventually reaches Lake Neuchâtel, one of Switzerland's largest lakes. Lake Neuchâtel is an ecologically important water body supporting diverse aquatic life and recreational activities. The advanced treatment helps minimize nutrient loading, protecting the lake from eutrophication and maintaining water quality.

The plant discharges into local watercourses that feed the Areuse River, which flows into Lake Neuchâtel, a large perialpine lake in western Switzerland. Lake Neuchâtel is part of the Rhine basin and supports diverse fish populations and migratory birds. Advanced treatment at LA SAGNE reduces phosphorus and nitrogen loads, helping to prevent algal blooms and preserve the lake's ecological balance.