OLIANA Wastewater Treatment Plant, Oliana, Catalunya, Spain

OLIANA is a wastewater treatment plant located in Oliana, in the Alt Urgell region of Catalunya, Spain. The facility serves a population of approximately 2,335 and operates with secondary treatment, which is standard for small agglomerations under Spanish and EU regulations. The plant has a designed capacity of 3,000 m³/day and currently treats a daily volume of 600.57 m³. As a secondary treatment plant, OLIANA meets the requirements of the EU Urban Waste Water Treatment Directive (91/271/EEC), which mandates secondary treatment for discharges into freshwater and estuaries from agglomerations of this size. The plant's capacity utilization is low, indicating ample headroom for future growth or seasonal variations. The treated effluent is discharged into the local watershed, which ultimately drains into the Segre River, a major tributary of the Ebro River. The Ebro River flows into the Mediterranean Sea, supporting diverse aquatic ecosystems and agricultural water use downstream. The plant plays a key role in protecting water quality in this inland region.

The OLIANA plant discharges into the Segre River basin, which flows into the Ebro River and then the Mediterranean Sea. The Segre River supports a variety of aquatic life and is used for irrigation in the surrounding agricultural areas. Protecting water quality in this watershed is important for maintaining ecological balance and supporting local communities.