Niagara-on-the-Lake Combined Sewer Overflows at Niagara Region Facilities

Data presented here is updated every three months. The data contains records from
September 01, 2017 to August 31, 2018.

CSO Location Date of OverflowVolumeReason for Overflow
N-O-T-L Plant
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Apr 23, 201823.187 Exceed Design
N-O-T-L Plant
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Apr 16, 201814.852 Snow Melt
Heavy Precipitation
William St SPS CSO
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Apr 16, 2018N/A Heavy Precipitation
Snow Melt
Lakeshore SPS
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Apr 16, 2018N/A Heavy Precipitation
Snow Melt
N-O-T-L Plant
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Oct 10, 20170.003 Heavy Precipitation
Exceed Design

Volume is measured in megalitres. (1 megalitre = 1 million litres)

Historical Overflow Data for Niagara-on-the-Lake

201720162015
Total Overflows: 8
Total Volume: 0.003
Total Overflows: 1
Total Volume: N/A
Total Overflows: 0
Total Volume: N/A

Overflows contain mostly Storm Water

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.

Historical Data

If you require more detailed information about a specific combined sewage overflow, you can contact the water & wastewater division.


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