MONTERROSO Wastewater Treatment Plant, Monterroso, Galicia, Spain

MONTERROSO is a wastewater treatment plant located in Monterroso, a municipality in the province of Lugo, Galicia, Spain. The plant serves a population of approximately 4,335 people, classifying it as a small agglomeration under EU standards. Its location in the rural interior of Galicia places it within the region's network of municipal wastewater infrastructure. As a plant serving fewer than 10,000 population equivalents, it falls under the EU Urban Waste Water Treatment Directive 91/271/EEC, which requires appropriate treatment based on the sensitivity of the receiving waters. Plants of this scale in Spain typically employ secondary biological treatment or equivalent technologies to meet regulatory standards. The treated effluent from MONTERROSO is discharged into local watercourses that eventually drain into the Ulla River basin, which flows into the Ria de Arousa, a coastal inlet of the Atlantic Ocean. This estuary is ecologically significant, supporting diverse marine life and shellfish fisheries. The plant's operation helps protect downstream water quality in this sensitive coastal environment.

MONTERROSO discharges into tributaries of the Ulla River, which flows into the Ria de Arousa, a large estuary on the Atlantic coast of Galicia. The ria is a productive ecosystem supporting shellfish beds, migratory fish, and diverse bird populations. The plant's treatment performance is critical to maintaining water quality in this ecologically sensitive area, which is also important for local fisheries and tourism.