Untreated Wastewater
Measures the percentage of wastewater that goes untreated across Canada.
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Untreated sewage ends up in our waterways by either getting pumped directly into waters with little to no treatment, or from combined sewer overflows (CSOs) where wastewater and stormwater flow together during heavy rainstorms.

Though treatment facilities are required to report direct discharge and combined sewer overflow events, this information is not readily accessible to the public. At the time of publication, this information had been requested from Environment and Climate Change Canada but had not been analyzed. As a result, this impact measure currently uses data published by CBC in December of 2016. Many Our Living Water Network members have increased calls for real-time, public notification of sewer overflow and discharge events.

In 2015, more than 205 billion litres of raw sewage and untreated wastewater flowed into Canada's rivers and oceans. That’s the equivalent of every Canadian dumping 70 bathtubs full of untreated sewage into our waters. Compared to 2014, that’s an increase of 1.9%. BC dumps the most untreated wastewater into rivers and oceans: 82.3 billion litres in 2015. Whereas Alberta dropped from 8 billion litres in 2013 to under 4 billion in 2015.

Federal wastewater regulations came into effect in 2015 which could drive reductions in direct discharge from treatment facilities. Combined Sewers, however, are out of the scope of these regulations and continue to cause challenges as regions experience more severe and frequent storm events.

5-Year target: To advance real-time public reporting on sewage overflow and discharge events in communities across Canada the a long term target of attaining commitments by governments to end sewage overflow events for all communities across Canada.

Last updated December 2016

Our Living Waters Network Members leading this conversation:

If you would like to be part of this conversation, email us at [email protected].

Note: The data presented here represents our best research given the time and resources at hand. We acknowledge there may be errors. This shared measurement system belongs to all members of the Our Living Water Network, so if you have any corrections for us, or ideas to share on this measure, please send us an email at [email protected].

Untreated Wastewater|Measures the percentage of wastewater that goes untreated across Canada.
Untreated Wastewater|Measures the percentage of wastewater that goes untreated across Canada.
Imagine a Canada where all waters are in good health: