Viana do Bolo Wastewater Treatment Plant - Galicia, Spain

The Viana do Bolo wastewater treatment plant is located in the municipality of Viana do Bolo, in the province of Ourense, Galicia, Spain. It serves a population of approximately 1,566 people, classifying it as a small agglomeration under EU regulations. The plant is currently closed, and its operational status reflects the end of its service life. As a secondary treatment facility, the plant was designed to meet EU Urban Waste Water Treatment Directive (91/271/EEC) standards for small agglomerations. The designed capacity of 2,500 m³/day indicates the plant was built to handle peak flows. The actual discharge volume recorded is 283.83 m³, suggesting low flow at the time of reporting. The plant's treated effluent was discharged into local watercourses that drain into the Bibei River, a tributary of the Sil River, which flows into the Minho River and eventually reaches the Atlantic Ocean. The surrounding region is characterized by mountainous terrain and a temperate climate, with the plant's operations supporting the protection of local streams and downstream aquatic ecosystems.

The Viana do Bolo plant discharged into local streams that feed the Bibei River, part of the Sil-Minho river system, which flows into the Atlantic Ocean. The watershed supports diverse aquatic life, including migratory fish species. The plant's secondary treatment helped reduce organic pollution and protect downstream water quality in this ecologically sensitive region.