'We don't make these decisions lightly': Nearly 60 million litres of sewage dumped into Winnipeg's rivers during the storm

The city released nearly 60 million litres of sewage in Winnipeg's rivers over the weekend – a difficult decision it says was made to protect Winnipegger's basements from flooding.

The rain and snow that walloped the city over the weekend brought as much as 70.5 millimetres of precipitation according to Environment and Climate Change Canada – leading to flooded streets and basements in low-lying areas of the city.

"When it rains, the [sewer] system can get very full and even overwhelmed," said Chris Carroll, manager of wastewater services for the city's water and waste department.

When the sewer system hits capacity, Carroll said the city will divert the excess sewage flow into the city's river system. He said if the sewage is not released, it will potentially backup and flood people's homes.

Carroll said from late Saturday night through to Monday morning, the city made a planned release of 59.6 million litres of sewage into Winnipeg's rivers.

"We don't make these decisions lightly. We don't like when we have to do this," he said. "They're difficult decisions that we have to make between having the environment absorb some of the flow, compared to the public health and property damage that may occur if you get wastewater or dilute wastewater backing up into your home."

He said the size of this sewage release is unusual and was made to specifically protect the sewer capacity in the city's south end sewage treatment plant. Though it was a significant release, Carroll said it only represents about five per cent of the total 1,256 million litres of sewage that were pumped through Winnipeg's three sewage treatment facilities this weekend.

"We haven't received these sewer flows to the plants like this for the past 20 years that we've been monitoring the data. So it was quite a remarkable situation," he said.

Carroll said the city is currently working on a Combined Sewer Overflow Master Plan, which he said will prevent these kinds of situations from happening. However, he said this is a generational plan that will take decades to complete.

"It's not something that can be done quickly, and it's not something that can be done inexpensively," he said. "Once those projects come on line, and we're incrementally improving them every year, the possibility of things like this happening goes down dramatically."