Cardeña Wastewater Treatment Plant, Cardeña, Andalucía, Spain

The Cardeña wastewater treatment plant is located in the municipality of Cardeña, in the province of Córdoba, Andalucía, Spain. It serves a small population of approximately 1,307 residents and is currently closed. The plant was designed with a capacity of 1,600 cubic meters per day and treated an average discharge volume of 236.89 cubic meters per day. The plant provided advanced treatment, which goes beyond secondary treatment to remove nutrients and other pollutants. Under the EU Urban Waste Water Treatment Directive (91/271/EEC), small agglomerations like Cardeña (under 2,000 population equivalent) are typically required to provide appropriate treatment, and advanced treatment is often implemented in sensitive areas to protect water quality. The treated effluent from the plant would have been discharged into local watercourses that drain into the Guadalquivir River basin, eventually reaching the Atlantic Ocean. The plant's operation helped protect the ecological health of the surrounding watershed, which supports diverse aquatic life and contributes to the region's water resources.

The Cardeña plant is located inland in the Guadalquivir River basin, which drains into the Atlantic Ocean via the Guadalquivir River. The watershed supports a variety of aquatic ecosystems and is important for regional biodiversity. The advanced treatment provided by the plant helped reduce nutrient loading and protect downstream water quality in this ecologically sensitive area.