Toronto's Water Mains: Sewage, Treatment, And You

Toronto has a network of wastewater and sewage lines that carry water to one of four treatment plants. The treated water is then released into Lake Ontario. The Ashbridges Bay Wastewater Treatment Plant, built in 1910, is the largest treatment plant and serves a population of 1,524,000. There are three other plants, the Highland Creek, Humber River, and North Toronto. The wastewater goes through five stages of treatment before being released back into the lake. Toronto has an average of 1,100 water main breaks per year, potentially diverting untreated wastewater back into waterways. Regular maintenance and repair of water mains and sewers are crucial to ensuring wastewater is properly treated. Thanks to the high standards of wastewater treatment, Toronto’s lakes and beaches are safer for swimming and fishing.