ARROYO DEL OJANCO Wastewater Treatment Plant, Segura de la Sierra, Andalucía

ARROYO DEL OJANCO is a municipal wastewater treatment plant located in Segura de la Sierra, within the province of Jaén, Andalucía, Spain. The facility serves a population equivalent of 2,748, classifying it as a small agglomeration under Spanish and EU regulations. It is situated inland, away from coastal areas, and its operations are integral to local water management in this rural region. 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. The designed capacity matches the population served at 2,748 m³/day, indicating a balanced infrastructure for the community's needs. As a secondary treatment facility, it employs biological processes to reduce organic matter and suspended solids before discharge. The treated effluent is discharged into a local watercourse, which eventually drains into the Guadalquivir River basin, one of Spain's major river systems. The Guadalquivir flows southwest through Andalucía and empties into the Gulf of Cádiz (Atlantic Ocean). The plant's operation helps protect the ecological health of the receiving waters and supports the region's water quality objectives.

The plant discharges into a tributary of the Guadalquivir River basin, which flows through Andalucía and into the Atlantic Ocean at the Gulf of Cádiz. The downstream environment supports diverse aquatic life and is important for regional biodiversity, including migratory fish species. The Guadalquivir basin is a key agricultural and ecological corridor, making effective wastewater treatment essential for maintaining water quality and ecosystem health.