More than three times the annual amount of raw sewage and storm water has been spilled into the Ottawa River so far this year and although the city hopes to start construction on a new wastewater dechlorination project soon, river health advocates say it’s a small step towards mending the problems with Ottawa’s sewer systems.
City council recently heard the numbers from the manager of environmental services, says Somerset Coun. Diane Holmes. Both the council and the province are regularly informed of spills into the river.
According to Natasha Wilson, of Ottawa Riverkeeper, a local environmental group, the spill of 1.3 billion litres of untreated waste water, is yet another indicator of a sewer system that has reached its limit.
“It’s now to the point that as little as two millimetres of rain … is potentially enough to cause the system to overflow and release raw sewage and storm water.”
She says increased rainfall, such as that experienced in July, coupled with an at-capacity sewer system that has seen few upgrades in the past 30 years, forces excess water to be dumped into Ottawa’s main waterway.
“In lieu of having flooding in our urban areas when it rains, the system has to release it directly into the river.”
Wilson says that when this happens, pharmaceuticals, industrial waste, and other toxins that are flushed down Ottawa’s toilets and drains end up in the river. The city’s new plan to remove chlorine, which she says can harm species living in the river, doesn’t go far enough to get the situation under control.
Michel Chevalier, manager of wastewater and drainage operations for the City of Ottawa, says the municipality is on track to meet chlorine reduction guidelines published this February by the Canadian Council of the Ministers of the Environment.
He says construction on a dechlorination addition to Ottawa’s east end wastewater treatment plant in will ideally start in the spring, with a maximum cost of $7 million.
“This is probably the worst case scenario, from a cost perspective,” says Chevalier. “The design is just starting, so it is too soon to comment of what the process will precisely entail.”
Spilling sewer water into the Ottawa River is nothing new, Wilson says, but the city has failed to be proactive enough, despite warnings about increased precipitation nearly a decade old. She says climate models continue to predict a swell in rainfall of 30 per cent or more in the near future.
Although dechlorination is a positive step, she says the problem lies with Ottawa’s aging sewer system, which for the most part uses one pipeline for storm and sewer water. This means that both end up in the river when there is a system overflow caused by rain.
Holmes says there are many ways to cut down on the amount of water going into Ottawa’s storm sewers, including providing incentives for home owners to replace asphalt with materials suited for better drainage, as well as building green roofs and planting more trees to help in soaking up excess rainwater.
However, she says the city is nowhere near mandating these kinds of changes.
“It’s more pressing to actually get control of the sewage that’s going into the waterways, so that’s where we’re putting our money this year,” explains Holmes. “But I certainly hope that we can get on to doing some of the other programs as well.”
Despite a recently tabled plan for $400 million dollars worth of upgrades to the city’s sewer system, Wilson says action has not been preventive enough.
“I think it’s been quite the opposite,” she says. “We’ve known about the changing weather patterns in this area, and yet we haven’t developed our infrastructure … to meet those needs.”
Although Wilson says the city has recently installed computerized regulators to reduce accidental overflows, she is concerned that she has heard little about the planned upgrades since the original motion.
“We haven’t seen too much momentum in putting some of these bigger measures in place.”