AUNA_DI_SOTTO Wastewater Treatment Plant, Schnals - Senales, Italy

AUNA_DI_SOTTO is a wastewater treatment plant located in the municipality of Schnals - Senales, in the Trentino-Alto Adige/Südtirol region of northern Italy. Situated in the alpine Vinschgau valley, this facility serves a small community of approximately 3,663 residents. The plant is part of the region's decentralized wastewater infrastructure, typical for mountainous areas where topography limits centralized systems. The plant provides secondary treatment, which is the standard biological treatment required under the EU Urban Waste Water Treatment Directive (91/271/EEC) for agglomerations with a population equivalent between 2,000 and 10,000. With a designed capacity of 4,000 m³/day and an average daily discharge of 725.14 m³/day, the plant operates well below its capacity, indicating room for future growth or seasonal variations. The treated effluent is discharged into local watercourses that drain into the Adige River basin, one of Italy's major river systems. The Adige flows south through Trentino and Veneto before emptying into the Adriatic Sea. The plant's operation is critical for protecting the sensitive alpine aquatic ecosystems and downstream water quality in the Adige River, which supports diverse aquatic life and is used for irrigation and recreation.

The plant discharges into local streams that feed into the Adige River, which flows through the Trentino-Alto Adige region and ultimately reaches the Adriatic Sea. The alpine watershed is ecologically sensitive, supporting cold-water fish species and diverse macroinvertebrate communities. Proper treatment is essential to prevent nutrient enrichment and maintain water quality in this high-altitude environment.