DOMODOSSOLA Wastewater Treatment Plant, Domodossola, Piemonte, Italy

The DOMODOSSOLA wastewater treatment plant is located in Domodossola, a town in the Piemonte region of northern Italy, near the Swiss border. The plant serves a population equivalent of 17,700, classifying it as a medium-sized agglomeration under EU regulations. Its location in the Toce River valley places it within the Po River basin, which ultimately drains into the Adriatic Sea. Under the EU Urban Waste Water Treatment Directive (91/271/EEC), agglomerations with a population equivalent between 10,000 and 150,000 are required to provide secondary treatment (biological treatment) as a minimum standard. For plants discharging into sensitive areas, such as those in the Po basin, tertiary treatment may be required to reduce nutrient loads. The regulatory framework ensures compliance with national and EU standards. The plant discharges treated wastewater into the local water system, which flows into the Toce River, a tributary of Lake Maggiore. Lake Maggiore is a large subalpine lake that drains into the Ticino River, a major tributary of the Po River. The Po River then flows eastward into the Adriatic Sea. The region supports diverse aquatic life, including fish species such as trout and perch, and the lake is an important resource for tourism and recreation.

The plant's treated effluent enters the Toce River, which flows into Lake Maggiore, one of Italy's largest subalpine lakes. Lake Maggiore drains into the Ticino River, a tributary of the Po River, which ultimately reaches the Adriatic Sea. The watershed supports diverse aquatic ecosystems, including fish populations and migratory birds. Nutrient loading from wastewater can contribute to eutrophication in the lake, making effective treatment crucial for water quality.