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The war to stem the tide of sewage flowing into the Ottawa River is a fight against the past.
The city is racing to replace archaic combined sewer pipes, which are the sole reason raw sewage is able to seep into Ottawa’s side of the river.
Combined sewers mix raw untreated sewage with stormwater in the same pipes, and heavy rain forces the city to open the valves, letting the combination loose on the river.
Only by separating the two systems can they reduce overflows. But therein lies the problem.
Combined sewers were the modus operandi for fledging cities such as Toronto, Kingston and Ottawa from the 1880s into the early 1960s.
All of the city’s urban core, including Sandy Hill and the Byward Market, are built on them, with separated sewers built in rings around downtown.
“They just didn’t have any idea about the risks or the issues back then,” said Theresa Mclenaghan, executive director of the Canadian Environmental Law Association.
No green thinkers
The sewers weren’t built for the number of people the city has today, and frankly, builders weren’t as concerned about pollution then, she adds.
It doesn’t help that these pipes were built to withstand 100-year storms, but increasing precipitation has changed that standard significantly.
To switch over all of those combined sewers would be a Herculean task, having to rip up nearly every downtown street along the way.