ARA Bennwil Wastewater Treatment Plant, Bennwil, Basel-Landschaft, Switzerland

ARA Bennwil is a municipal wastewater treatment plant located in Bennwil, a village in the Basel-Landschaft canton of Switzerland. The plant serves a small population of 192 residents, reflecting the rural character of the area. It operates as part of Switzerland's decentralized wastewater infrastructure, which emphasizes local treatment for smaller communities. The plant provides secondary treatment, which typically involves biological processes to reduce organic matter and suspended solids. With a designed capacity of 450 m³/day and an actual discharge volume of 87.15 m³/day, the facility operates well below its capacity, indicating ample headroom for future growth or seasonal variations. Swiss wastewater treatment plants are regulated under national ordinances that align with the EU Urban Waste Water Treatment Directive, ensuring high effluent quality standards even for small agglomerations. The treated effluent from ARA Bennwil is discharged into local watercourses that eventually drain into the Rhine River basin. The Rhine is one of Europe's major rivers, flowing through Switzerland, Germany, and the Netherlands before reaching the North Sea. The plant's secondary treatment helps protect downstream aquatic ecosystems, including the Rhine's diverse fish populations and migratory species.

ARA Bennwil discharges into small streams in the Basel-Landschaft region, which are part of the Rhine River basin. The Rhine flows northward through Switzerland and into Germany, eventually reaching the North Sea. This watershed supports important aquatic habitats, including spawning grounds for salmon and other migratory fish. The plant's secondary treatment reduces organic pollution, helping maintain water quality in the sensitive Rhine ecosystem.