Sewage pollution of Toronto’s water among worst in Ontario: study

WATCH: Toronto scores poor marks for dumping sewage in Lake Ontario. Jackson Proskow reports. 

TORONTO – A new report suggests the pollution in and treatment of Lake Ontario near Toronto is among the worst in Ontario.

The report, released by the non-profit Eco-Justice, analyzed 12 Ontario municipalities’ sewage treatment and discharge. London and Sarnia are tied for last and Peel Region ranked first. Toronto however, came in third last.

“The primary reason that Toronto ranks so low is that they’ve got antiquated, outdated sewage infrastructure: mainly combined sewers,” Liat Podolsky, a scientist at Eco-Justice, said.

Combined sewers use the same pipes to manage storm water and sewage. The problem arises when large storm events such as July’s record storm overwhelm the sewers and cause raw, untreated sewage to seep into Lake Ontario.

In 2011, “billions of litres of either raw or partially treated sewage” was dumped into Lake Ontario, Podolsky said.

And when there is a spike of raw or partially-treated sewage in the water it can cause serious effects to the local eco-system, reduce bio-diversity and increase levels of E.Coli which can cause illnesses in people, Podolsky said. Traces of E.Coli are present in the water but normally, at safe levels.

Jackson Proskow travelled across Canada to discover just how much of what we flush down our drains ends up in rivers, lakes and oceans – and ends up coming back through our kitchen taps.

Much of the flood water that wreaked havoc on people’s homes following the July flood may have been contaminated with some of the overflow sewage.

Combined sewers have traditionally been used in Toronto and are still a problem, according to city officials.

“Unfortunately when you have a combined sewer system, you have combined sewer overflows,” Acting-Director of Water Infrastructure Management for the city of Toronto, Ted Bowering, said.

But investments are happening. Toronto has already replaced most of its combined sewers.  In the eastern and western beaches, the city built large underground tanks to capture the flow of sewage and send it for treatment.

“Most of the sewer system, even in the combined area, is separated now. So the combined overflows that we do have are largely still storm water with a certain amount of sewage in them,” Bowering said. “Moving forward we have a plan to deal with all the rest of the combined sewer overflows in the city.”

That plan aims to deal with combined sewers along the Don River, Massey Creek and the inner Toronto harbour. Bowering said the city is spending close to $1.5 billion over several years to upgrade infrastructure in those areas.

But is Toronto’s drinking water safe? Yes, but sewage seeping into Lake Ontario could have an effect. Three out of four people in Ontario rely on Lake Ontario for their drinking water and all drinking water is treated before it reaches our taps. The worry however, Podulsky said, is that untreated sewage flow into Lake Ontario could lead to the cost of treating that water steadily increasing.