Calamandrana Wastewater Treatment Plant, Asti, Piemonte, Italy

The Calamandrana wastewater treatment plant is located in the town of Calamandrana, in the province of Asti, Piemonte region, Italy. It serves a population of approximately 5,400 residents, classifying it as a small to medium agglomeration under Italian and EU regulations. The plant provides secondary treatment, which is the minimum standard required by the EU Urban Waste Water Treatment Directive (91/271/EEC) for freshwater discharges from agglomerations of this size. Its designed capacity is 6,400 m³ per day, with an actual discharge volume of 358.90 m³ per day, indicating ample reserve capacity. The treated effluent is discharged into a local watercourse that flows into the Tanaro River, a major tributary of the Po River. The Po River basin is the largest in Italy and drains into the Adriatic Sea. The plant plays a key role in protecting the water quality of the Tanaro and Po rivers, which support diverse aquatic ecosystems and are used for irrigation and recreation.

The plant discharges into a local stream that feeds into the Tanaro River, a major tributary of the Po River. The Po River flows eastward across northern Italy and empties into the Adriatic Sea. This watershed supports important agricultural activities and provides habitat for fish species such as the European eel and various cyprinids. The plant's secondary treatment helps reduce nutrient loads and organic pollution, contributing to the ecological health of the Po River basin.