ARINS SANTIAGO Wastewater Treatment Plant, A Barcia, Galicia, Spain

ARINS SANTIAGO is a wastewater treatment plant located in A Barcia, a locality within the municipality of Teo, in the province of A Coruña, Galicia, Spain. The plant serves a population of approximately 4,050 people, placing it in the small agglomeration category under EU regulations. Its designed capacity is 1.00 cubic hectometer per year, reflecting its role in managing local domestic wastewater. As a Spanish facility, ARINS SANTIAGO operates within the framework of the EU Urban Waste Water Treatment Directive (91/271/EEC), transposed into national law via Royal Decree-Law 11/1995 and subsequent regulations. For agglomerations of this size (under 10,000 population equivalent), the directive requires appropriate treatment, typically secondary treatment, to protect receiving waters. Compliance with Spanish water quality standards is expected. The plant discharges treated effluent into the local hydrological network, which ultimately drains into the Atlantic Ocean via the Tambre River basin. The Tambre River flows through Santiago de Compostela and into the Ría de Muros e Noia, a coastal inlet of ecological importance. The region's Atlantic climate, with abundant rainfall, influences the dilution and assimilation capacity of receiving waters. The plant's operation contributes to protecting downstream aquatic ecosystems and supporting water quality in the Tambre catchment.

ARINS SANTIAGO discharges into the Tambre River basin, which flows into the Ría de Muros e Noia on the Atlantic coast of Galicia. This ria is a productive estuarine environment supporting diverse marine life, including shellfish beds and migratory fish species. The plant's treatment helps maintain water quality in this ecologically sensitive coastal system, which is influenced by Atlantic tides and seasonal rainfall patterns.