Amarante S Goncalo Wastewater Treatment Plant, Amarante, Portugal

Amarante S Goncalo is a former wastewater treatment plant located in Amarante, Porto District, Portugal. The facility served the urban agglomeration of Amarante, including the parishes of São Gonçalo, Madalena, Cepelos, and Gatão. As a closed plant, it is no longer operational, but its infrastructure reflects the scale of treatment needed for a medium-sized Portuguese town. The plant was designed with advanced treatment capabilities, which typically includes nutrient removal and disinfection beyond secondary treatment. This level of treatment aligns with the requirements of the EU Urban Waste Water Treatment Directive (91/271/EEC) for sensitive areas. The designed capacity of 18,700 m³/day suggests it served a population equivalent of roughly 50,000 to 80,000 people, based on standard loading rates. The treated effluent from this plant would have discharged into the Tâmega River, a tributary of the Douro River, which flows into the Atlantic Ocean at Porto. The Douro basin supports diverse aquatic life and is an important ecological corridor in northern Portugal. The advanced treatment helped protect water quality in this sensitive river system.

The plant discharged into the Tâmega River, a major tributary of the Douro River. The Douro River basin is ecologically significant, supporting diverse fish species and providing habitat for migratory birds. The river flows through the Porto region before reaching the Atlantic Ocean, where it influences coastal water quality. Advanced treatment at this plant helped reduce nutrient loads and protect downstream ecosystems.