IDL_COLLESALVETTI Wastewater Treatment Plant, Collesalvetti, Tuscany

IDL_COLLESALVETTI is a municipal wastewater treatment plant located in Collesalvetti, a town in the Tuscany region of Italy. The facility serves a population of approximately 3,500, classifying it as a small agglomeration under Italian and EU regulations. It is situated inland, about 10-50 km from the Tyrrhenian coast, and its operations are part of the regional water management infrastructure managed by local authorities. The plant provides secondary treatment, which is the standard required by the EU Urban Waste Water Treatment Directive (91/271/EEC) for agglomerations of this size discharging into freshwater or estuaries. With a designed capacity of 4,000 m³/day and an average discharge volume of 693 m³/day, the plant operates well below its capacity, indicating room for future growth or seasonal variations. The treated effluent is discharged into local watercourses that eventually flow into the Arno River basin, which drains into the Tyrrhenian Sea. This area supports diverse aquatic life and is important for regional agriculture and tourism. The plant's secondary treatment helps reduce organic pollutants and suspended solids, protecting downstream water quality and the sensitive coastal ecosystem of the Tyrrhenian Sea.

The plant discharges into small streams that feed into the Arno River, which flows through Tuscany and empties into the Tyrrhenian Sea near Pisa. The Arno basin supports a variety of freshwater species and is a key water resource for agriculture and urban areas. The Tyrrhenian Sea is a semi-enclosed basin with important marine habitats, including seagrass meadows and coral formations, which benefit from controlled nutrient and pollutant loads from inland sources.