Figueiro Wastewater Treatment Plant, Amarante, Portugal

Figueiro is a secondary wastewater treatment plant located in Lenteiros, Figueiró (Santiago e Santa Cristina), Amarante, Porto District, Portugal. It serves a population of approximately 3,000 people and has a designed capacity of 3,500 m³/day, with an average discharge volume of 500.19 m³/day. The plant is situated inland, more than 50 km from the coast, and operates under Portuguese and EU regulatory frameworks. As a secondary treatment facility, Figueiro provides biological treatment to reduce organic matter and suspended solids, meeting the standards required by the EU Urban Waste Water Treatment Directive (91/271/EEC) for agglomerations of this size. The plant's capacity utilization is low, indicating ample headroom for future growth or seasonal variations. It is operated as part of the municipal wastewater infrastructure serving Amarante and surrounding areas. The treated effluent from Figueiro is discharged into local streams that eventually flow into the Tâmega River, a tributary of the Douro River. The Douro River basin is ecologically significant, supporting diverse aquatic life and providing water for agriculture and human consumption downstream. The plant's secondary treatment helps protect water quality in this sensitive watershed.

Figueiro discharges treated wastewater into local watercourses that drain into the Tâmega River, a major tributary of the Douro River. The Douro River flows westward through Portugal and empties into the Atlantic Ocean near Porto. The watershed supports diverse aquatic ecosystems, including fish species such as trout and barbel, and is important for regional biodiversity. Secondary treatment reduces organic pollutants and nutrients, helping to maintain water quality in this ecologically sensitive basin.