Puigcerdà Wastewater Treatment Plant, Puigcerdà, Catalonia, Spain

The Puigcerdà wastewater treatment plant is located in the town of Puigcerdà, in the Cerdanya comarca of Girona, Catalonia, Spain. It serves a population of approximately 15,690 people, classifying it as a medium-sized agglomeration under EU regulations. The plant is situated in the Pyrenees near the French border, at an elevation of over 1,100 meters. As a Spanish facility, the plant operates under the EU Urban Waste Water Treatment Directive (91/271/EEC), which requires secondary treatment for agglomerations of this size. The directive also mandates more stringent treatment if the discharge enters sensitive areas, which is relevant given the plant's mountainous location and potential impact on headwater streams. Regulatory compliance ensures appropriate treatment for the population served. The treated effluent from the plant likely discharges into the Segre River, a major tributary of the Ebro River, which flows into the Mediterranean Sea. The Segre River supports diverse aquatic life and is an important water resource for irrigation and ecosystems in the region. The plant's operation helps protect water quality in this transboundary river system, which is shared with Andorra and France.

The Puigcerdà plant discharges into the Segre River, a key tributary of the Ebro River, which ultimately flows into the Mediterranean Sea. The Segre River basin supports diverse aquatic ecosystems, including fish species such as brown trout and barbel, and provides habitat for migratory birds. The plant's location in the Pyrenees means its discharge affects headwater streams that are ecologically sensitive, requiring careful management to maintain water quality and biodiversity.