IMPIANTO_C_DA_S_LEO Wastewater Treatment Plant, Sant'Anna, Sicily

IMPIANTO_C_DA_S_LEO is a municipal wastewater treatment plant located near Sant'Anna, in the municipality of Caltabellotta, Agrigento province, Sicily, Italy. The plant serves a population of approximately 4,800 residents, classifying it as a small agglomeration under Italian and EU regulations. The plant provides secondary treatment, which is the minimum standard required by the EU Urban Waste Water Treatment Directive (91/271/EEC) for freshwater discharges from agglomerations of this size. Its designed capacity is 5,200 m³/day, with an average daily discharge of 950.23 m³/day, indicating operational capacity well below design limits. The treated effluent is discharged into the local watershed, which ultimately drains into the Mediterranean Sea. Sicily's Mediterranean climate and karstic geology make water resources sensitive to pollution, and the plant's secondary treatment helps protect downstream aquatic ecosystems and coastal water quality.

The plant discharges into the local drainage network that flows toward the southern coast of Sicily, eventually reaching the Mediterranean Sea. The receiving waters support diverse marine life and are part of a region with significant ecological importance, including seagrass meadows and coastal habitats. Secondary treatment reduces organic load and suspended solids, mitigating eutrophication risks in the coastal zone.