SAHAGUN Wastewater Treatment Plant, Sahagún, Castilla y León, Spain

SAHAGUN is a wastewater treatment plant located in Sahagún, within the province of León, Castilla y León, Spain. It serves a population of approximately 5,694 people, making it a small agglomeration under EU classification. The plant is situated along the Carretera de Palencia a Sahagún and operates as a key municipal facility for the area. 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. Secondary treatment typically involves biological processes to reduce organic matter and suspended solids. The plant's designed capacity is 5,694 population equivalents, and it handles a daily discharge volume of 954 cubic meters. The treated wastewater is discharged into a local watercourse, which eventually drains into the Cea River, a tributary of the Esla River, and ultimately into the Duero River basin. This river system supports diverse aquatic life and is important for irrigation and ecological balance in the region. The plant's operation helps protect downstream water quality in the Duero watershed.

The plant discharges into a local stream that flows into the Cea River, a tributary of the Esla River, which is part of the larger Duero River basin. The Duero River eventually reaches the Atlantic Ocean near Porto, Portugal. The watershed supports agricultural activities and provides habitat for fish species such as barbel and trout. The plant's secondary treatment helps reduce nutrient loading and organic pollution, contributing to the ecological health of the downstream river system.