Data presented here is updated every three months. The data contains records from September 01, 2023 to August 31, 2024.
Volume is measured in megalitres. (1 megalitre = 1 million litres)
While the volume of an overflow may seem large, the amount of untreated sewage present in the overflow is small when compared to the amount of stormwater or snow melt.
Niagara typically treats about 80,000 megalitres of sewage each year. The vast majority of wastewater discharged into the sewer system receives full treatment and only a small percentage of this sewage overflows. These overflows usually only occur during periods of heavy rain or during seasonal snow melts.
If you require more detailed information about a specific combined sewage overflow, you can contact the water & wastewater division.