Collelongo Capoluogo Wastewater Treatment Plant, Collelongo, Italy

Collelongo Capoluogo is a municipal wastewater treatment plant located in Collelongo, a town in the province of L'Aquila, Abruzzo, Italy. The plant serves a population of approximately 2,300 residents, making it a small-scale facility within the Italian wastewater infrastructure. It is situated inland, away from coastal areas, and operates under Italian and European Union regulations. The plant provides secondary treatment, which is the standard biological treatment required under the EU Urban Waste Water Treatment Directive (91/271/EEC) for agglomerations of this size. The designed capacity is 2,500 m³/day, with an actual discharge volume of 455.32 m³/day, indicating that the plant operates well below its capacity. This suggests room for future growth or seasonal variations in flow. The treated effluent is discharged into local water bodies that eventually drain into the Tyrrhenian Sea via the Liri-Garigliano river system. The plant plays a key role in protecting the local watershed and downstream ecosystems from untreated sewage, supporting water quality in the region's rivers and coastal areas.

The plant discharges into the Liri-Garigliano river basin, which flows through central Italy and empties into the Tyrrhenian Sea. The watershed supports diverse aquatic life and is used for agriculture and recreation. Secondary treatment reduces organic pollutants and suspended solids, helping to maintain ecological balance in the river and downstream coastal zone.