COLLI Wastewater Treatment Plant, Monte San Giovanni Campano, Lazio

COLLI is an advanced wastewater treatment plant located in Monte San Giovanni Campano, in the province of Frosinone, Lazio, Italy. The plant serves a small population of 400 residents, reflecting its role in a rural or small-town setting within the Italian wastewater infrastructure. As an advanced treatment facility, COLLI provides a higher level of pollutant removal beyond secondary treatment, which is typical for plants in sensitive areas under the EU Urban Waste Water Treatment Directive (91/271/EEC). The plant has a designed capacity of 400 cubic meters per day and discharges a volume of 79.19 cubic meters per day, indicating it operates well below its capacity. The treated effluent is discharged into the local watershed, which ultimately drains into the Tyrrhenian Sea via the Liri-Garigliano river system. The plant's advanced treatment helps protect the water quality of this river basin and the downstream coastal environment, supporting aquatic life and reducing nutrient loading.

The plant discharges into the Liri-Garigliano river basin, which flows through Lazio and into the Tyrrhenian Sea. This watershed supports diverse aquatic ecosystems and is important for regional water resources. The advanced treatment level helps minimize nutrient and pollutant loads, protecting downstream habitats and the coastal marine environment from eutrophication.