ZUFRE Wastewater Treatment Plant, Zufre, Andalucía, Spain

ZUFRE is a wastewater treatment plant located in Zufre, a municipality in the Sierra de Huelva region of Andalucía, Spain. The plant serves a small population of approximately 1,200 residents and was designed with a capacity of 2,100 cubic meters per day. It is currently listed as closed. As a secondary treatment facility, ZUFRE would have provided biological treatment to reduce organic matter and suspended solids. Under the EU Urban Waste Water Treatment Directive (91/271/EEC), agglomerations with a population equivalent (PE) between 2,000 and 10,000 typically require secondary treatment. Although ZUFRE serves fewer than 2,000 people, Spanish regulations may still mandate appropriate treatment to protect local water bodies. The plant is situated inland, more than 50 km from the coast, in the Guadiana River basin. Treated effluent would have discharged into local streams that eventually flow into the Guadiana River and then into the Gulf of Cádiz (Atlantic Ocean). The surrounding area is ecologically sensitive, supporting Mediterranean woodland and aquatic habitats.

ZUFRE is located in the Sierra de Huelva, part of the Guadiana River basin. The nearest river is the Rivera de Huelva, a tributary of the Guadiana. The Guadiana flows southward, forming part of the Spain-Portugal border before emptying into the Gulf of Cádiz. The region supports diverse aquatic life, including species such as the Iberian barbel and freshwater crayfish. The plant's closure may reduce local pollution loads, but historical discharges could have impacted downstream water quality.