MERGOZZO Wastewater Treatment Plant, Candoglia, Piemonte, Italy

MERGOZZO is a wastewater treatment plant located in Candoglia, a frazione of Mergozzo in the Verbano-Cusio-Ossola province of Piemonte, Italy. The plant serves a population of approximately 6,868 people, classifying it as a small-to-medium agglomeration under the EU Urban Waste Water Treatment Directive (UWWTD). The facility is situated near the Toce River, which flows into Lake Maggiore, a major subalpine lake. As an Italian plant serving fewer than 10,000 people, MERGOZZO is subject to the EU UWWTD (91/271/EEC), which requires appropriate treatment based on the sensitivity of the receiving waters. Italian regulations mandate secondary treatment for inland discharges from agglomerations of this size, with possible tertiary treatment if the receiving water body is designated as sensitive. The plant's design capacity and operational status are consistent with typical municipal infrastructure for this population tier. The treated effluent from MERGOZZO ultimately discharges into the Toce River, a tributary of Lake Maggiore. Lake Maggiore is a large, deep lake that drains via the Ticino River into the Po River and then the Adriatic Sea. The lake supports diverse aquatic life and is an important resource for tourism and drinking water. Proper wastewater treatment is critical to prevent eutrophication and protect the lake's ecological health.

The MERGOZZO plant discharges into the Toce River, which flows into Lake Maggiore, one of Italy's largest subalpine lakes. Lake Maggiore drains via the Ticino River into the Po River, ultimately reaching the Adriatic Sea. The lake supports diverse aquatic ecosystems, including fish species like whitefish and perch, and is a vital water resource for the region. Effective treatment helps prevent nutrient loading and maintains water quality in this ecologically sensitive lake system.