NAVALENO Wastewater Treatment Plant, Navaleno, Castilla y Leon, Spain

NAVALENO is a wastewater treatment plant located in the town of Navaleno, in the province of Soria, Castilla y Leon, Spain. It serves a population of approximately 4,100 residents, making it a small-scale municipal facility. The plant is situated along the Carretera de Sagunto a Burgos road, in a rural inland area. The plant operates with secondary treatment, which is the standard level required under the EU Urban Waste Water Treatment Directive (91/271/EEC) for agglomerations of this size. Secondary treatment typically involves biological processes to reduce organic matter and suspended solids. The plant's designed capacity is 4,100 m³/day, and it treats an average daily volume of about 622 m³, indicating it operates well below its capacity. The treated effluent is discharged into a local watercourse, which eventually drains into the Duero River basin. The Duero River flows westward through Spain and Portugal, emptying into the Atlantic Ocean. The plant plays a key role in protecting the local aquatic environment and downstream water quality in the Duero basin.

The plant discharges into a tributary of the Duero River, which flows through the Castilla y Leon region and into Portugal before reaching the Atlantic Ocean. The Duero basin supports diverse aquatic life and is an important agricultural and ecological corridor. The plant's secondary treatment helps reduce nutrient and organic pollution, safeguarding the river's ecological health and downstream water uses.