LUCENA DEL CID Wastewater Treatment Plant, Llucena / Lucena del Cid, Spain

LUCENA DEL CID is an advanced wastewater treatment plant located in Llucena / Lucena del Cid, within the province of Castellón in the Comunitat Valenciana, Spain. The facility serves a population of approximately 4,044 and has a designed capacity of 4,185 cubic meters per day, with a current discharge volume of 359.60 cubic meters per day. As an advanced treatment plant, it provides a higher level of pollutant removal beyond secondary treatment, ensuring high-quality effluent. The plant operates under Spain's implementation of the EU Urban Waste Water Treatment Directive (91/271/EEC), which requires appropriate treatment for agglomerations based on population size and receiving water sensitivity. For a plant of this scale, advanced treatment aligns with standards for sensitive areas or reuse purposes. The facility is situated inland, more than 10 km from the coast, reducing direct marine discharge risks. The treated effluent is discharged into local watercourses that drain toward the Mediterranean Sea. The plant plays a key role in protecting the region's water resources, supporting both ecological health and potential water reuse in an area with Mediterranean climate and seasonal water scarcity.

The plant discharges into local streams that flow through the Mijares River basin, ultimately reaching the Mediterranean Sea near Castellón de la Plana. This coastal region supports diverse aquatic life and is important for tourism and agriculture. Advanced treatment helps minimize nutrient loading and protects downstream ecosystems, including seagrass meadows and fish habitats in the coastal zone.