Although the abundant 2021 rainy season has pumped up Lake to Chapala to 75 percent of full holding capacity, recent news on the state of its pollution levels is rather bleak.
According to data collected over the past three years through the National Water Commission (Conagua) Network for the Measurement of Water Quality, the lake is contaminated with alarming amounts of coliform fecal matter detected at ten of the 35 of the monitoring stations the agency monitors. High oxygen demand, an indicator of pollution, was registered at 16 of the test sites.
Only nine of the stations where samples are collected met the quality standards considered suitable for human consumption without undergoing purification processes.
Conagua figures were compiled every three months during 2018 and 2019, but only once last year, as normal procedures were curtailed by the Covid-19 pandemic.
With rising waters expected to dilute contaminants, the picture may be less grim after testing for 2021 is completed. But persistent issues of direct dumping of raw sewage that is not filtered through shoreline treatment plants means that plenty of work lies ahead to make the lake clean and healthy.