Carvalhal Wastewater Treatment Plant, Grândola, Portugal

Carvalhal is a wastewater treatment plant serving the town of Carvalhal in the municipality of Grândola, Setúbal district, Portugal. The plant treats wastewater from a population equivalent of 2,900, classifying it as a small agglomeration under Portuguese and EU regulations. The facility employs advanced treatment processes, which go beyond the secondary treatment standard required by the EU Urban Waste Water Treatment Directive (91/271/EEC) for sensitive areas. With a designed capacity of 3,045 m³/day and an average discharge volume of 483.52 m³/day, the plant operates well below its capacity, indicating room for future growth. The treated effluent is discharged into the local environment, likely into a water body that drains into the Atlantic Ocean, given the plant's proximity to the coast. The advanced treatment ensures high-quality effluent, protecting downstream ecosystems and supporting the region's environmental goals.

The plant is located within 10 km of the Atlantic coast, in the Setúbal region of Portugal. The treated wastewater likely discharges into a small stream or directly into coastal waters, eventually reaching the Atlantic Ocean. This coastal area supports diverse marine life and is part of a broader watershed that includes the Sado Estuary, a vital habitat for migratory birds and aquatic species. Advanced treatment helps minimize nutrient loading and protect these sensitive coastal ecosystems.