La Joya Wastewater Treatment Plant, Durango, Mexico

La Joya wastewater treatment plant is located in the town of La Joya, within the municipality of Poanas, Durango, Mexico. The facility serves a population of about 1,917 residents, reflecting its role in managing domestic wastewater for this small community in northern Mexico. The plant operates with secondary treatment, which is the standard biological treatment process for removing organic matter and suspended solids. With a designed capacity of 1,036.80 cubic meters per day and an actual discharge volume of 181.44 cubic meters per day, the plant operates well below its capacity, indicating potential for future growth or seasonal variations. Under Mexican regulations (NOM-001-SEMARNAT-1996 and subsequent updates), secondary treatment is required for municipal wastewater discharges to protect water quality. The treated effluent from La Joya is discharged into local watercourses that ultimately drain into the Nazas River basin, part of the larger hydrological system of the Mexican Plateau. This region is semi-arid, making water quality management critical for downstream agricultural and ecological uses. The plant's operation helps reduce pollution loads in the watershed, supporting local water resources and biodiversity.

The plant discharges into the Nazas River basin, which flows through Durango and Coahuila before ending in the Laguna de Mayran, an endorheic lagoon system. This semi-arid region relies heavily on the Nazas River for irrigation and domestic water supply. The treated effluent contributes to maintaining base flows and reducing nutrient loading, which is important for preventing eutrophication in downstream water bodies and supporting aquatic life in a water-scarce environment.