Impianto C/da Margio Natale Wastewater Treatment Plant, Milena, Sicily

Impianto C/da Margio Natale is a municipal wastewater treatment plant located in Villaggio San Martino, Milena, in the province of Caltanissetta, Sicily, Italy. The plant serves a population of approximately 2,570 people, 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. With a designed capacity of 2,850 m³/day and a reported discharge volume of 430.50 m³/day, the plant operates well below its capacity, indicating room for future growth or seasonal variability. The treated effluent is discharged into the local watershed, which ultimately drains into the Mediterranean Sea. The plant plays a key role in protecting the region's water quality, particularly given Sicily's semi-arid climate and the importance of groundwater resources for agriculture and drinking water.

The plant discharges into the inland watershed of central Sicily, which drains via seasonal streams toward the Mediterranean Sea. The region's water resources are under pressure from agricultural runoff and limited rainfall, making effective wastewater treatment critical for protecting downstream aquatic habitats and coastal water quality. The receiving water body supports diverse aquatic life and is part of a broader ecological network that includes important migratory corridors for birds.