DP01402702_DUBINO_NUOVA_OLONIO Wastewater Treatment Plant, Nuova Olonio, Italy

The DP01402702_DUBINO_NUOVA_OLONIO wastewater treatment plant is located in Nuova Olonio, a frazione of Dubino in the province of Sondrio, Lombardy, Italy. Situated in the Valtellina valley along the Adda River, the plant serves a population equivalent of approximately 4,000 residents, reflecting a small to medium agglomeration in the Alpine foothills. The plant employs advanced treatment processes, which go beyond secondary treatment to remove nutrients and other pollutants. With a designed capacity of 5,000 m³/day and an average daily flow of 791.86 m³/day, the facility operates well below its hydraulic capacity. As an Italian plant, it falls under the EU Urban Waste Water Treatment Directive (91/271/EEC), which requires advanced treatment for discharges into sensitive areas, such as the Alpine watershed. The treated effluent is discharged into the Adda River, a major tributary of the Po River, which flows into the Adriatic Sea. The plant plays a crucial role in protecting the water quality of the Adda and Po basins, supporting aquatic ecosystems and downstream uses including irrigation and recreation.

The plant discharges into the Adda River, which flows through the Valtellina valley and joins the Po River near Cremona. The Po River then empties into the Adriatic Sea via the Po Delta. The Adda River supports diverse aquatic life, including fish species such as brown trout and grayling, and its waters are used for irrigation in the Po Valley. The advanced treatment level helps minimize nutrient loading, protecting the sensitive Alpine and Po Delta ecosystems from eutrophication.