Leon Wastewater Treatment Plant: Serving 166,116 People in León, Guanajuato

The Leon wastewater treatment plant is a municipal facility located in León, Guanajuato, Mexico, serving a population of approximately 166,116 residents. Situated in the central highlands of Mexico, the plant is part of the city's sanitation infrastructure, which manages wastewater from urban and industrial sources in one of the country's most populous inland cities. As a large agglomeration serving over 150,000 people, the plant is expected to meet secondary or advanced treatment standards under Mexican regulation NOM-001-SEMARNAT-1996, which sets maximum permissible limits for pollutants in wastewater discharges into national waters. Facilities of this scale typically incorporate biological treatment stages to reduce organic load and suspended solids before discharge. The treated effluent is discharged into the Lerma River basin, which flows westward through Guanajuato and Michoacán before emptying into Lake Chapala, Mexico's largest freshwater lake. The Lerma-Chapala basin supports diverse aquatic ecosystems and provides water for agriculture, industry, and municipal use downstream. Proper wastewater treatment at Leon is critical to protecting water quality in this ecologically and economically important watershed.

The plant discharges into the Lerma River basin, which drains into Lake Chapala, the largest freshwater lake in Mexico. This watershed supports a variety of aquatic species and provides irrigation water for the surrounding agricultural region. The lake is also a key habitat for migratory birds and endemic fish species, making nutrient and pollutant control essential for maintaining ecological balance in the basin.