Sewage and rivers — a bad combination

Hey there, time traveller!
This article was published 05/07/2023 (840 days ago), so information in it may no longer be current.

The magnitude of raw sewage discharged into Winnipeg rivers last year is difficult to overstate.

The precise number is 27.5 billion litres of diluted, untreated sewage, according to City of Winnipeg data released last week. That’s enough to fill 11,010 Olympic-sized swimming pools, or an average of 30 swimming pools a day. It’s more than twice the 10-year average of 10.9 billion litres a year.

And that’s just from the city’s combined sewer system, which services about 32 per cent of Winnipeg. It doesn’t include other sewage spills that occur regularly from pump malfunctions, clogged pipes or discharges from treatment plants, which divert untreated sewage into the river when capacity is exceeded.

The reason for the high volume of combined sewer overflows last year: more rain, and more periods of intense rain, than usual.

Like many cities in North America, Winnipeg still services a portion of its older neighbourhoods with combined sewers, where sewage and street runoff are collected in a single pipe and treated prior to discharge into the river. During heavy rainfalls or snowmelts, the system can’t handle the combined flow of water and sewage and both are diverted directly into the river.

The city estimates about four per cent of those discharges is sewage, the rest is runoff. That’s still 1.1 billion litres of untreated sewage dumped into Winnipeg rivers last year (enough to fill 440 Olympic-sized swimming pools).

The environmental degradation from those spills is difficult to quantify. However, they do contribute to phosphorous build-up and algae blooms in Manitoba’s rivers and lakes, which contaminate beaches and threaten fish stocks.

Winnipeg is not the only source contaminating Manitoba’s rivers and lakes. Most of the nutrients originate upstream, including from the United States. Agriculture is also a major contributor.

Still, Winnipeg must do its part by eliminating, or substantially reducing, the raw sewage it dumps into rivers. The city has been making slow progress on that front by separating combined sewers in older neighbourhoods a little each year. It’s an expensive and time-consuming proposition that carries an estimated price tag of $2.3 billion. At current spending levels, it would take until 2095 to reach the city’s goal of eliminating 85 per cent of combined sewer overflows.

City hall is doing its part. It recently increased its annual combined sewer budget to $45 million (up from $30 million). However, annual spending has to reach $90 million to meet the 85-per-cent target by 2045.

City hall can’t do it alone. Like any large infrastructure project, the city requires financial support from senior levels of government. Unfortunately (and somewhat surprisingly in this age of environmental awareness), neither the province nor the federal government has committed any funding to Winnipeg’s combined sewer program.

Both levels of government talk a good talk about improving the health of the province’s rivers and lakes. Yet when it comes to fixing one of the major sources of contaminants to Lake Winnipeg, they are missing in action.

Manitoba’s Progressive Conservative government has underspent its infrastructure budget every year by hundreds of millions of dollars since it was elected in 2016. It has the financial capacity to help fix Winnipeg’s combined sewer system and reduce the amount of raw sewage dumped into rivers. But to date, it has shown no interest in doing so. Neither has the Liberal government in Ottawa, which cites the environment as one of its top priorities.

It’s time for both of those levels of government to step up — talk about the environment is cheap. Remediation of major systems is not.