By Jen Lahey
On sunny summer days, the beaches along the Ottawa River tend to play host to swimmers, picnickers, and those generally looking to enjoy the natural beauty of the waterway.
But in Ottawa, and in many cities across the country, the type of sewage system that we have means that when it storms, the “combined sewer overflow” system gets overloaded, and according to the city’s website, “the combined sewer cannot handle the high volume of storm water runoff entering the system, in addition to the wastewater. Most of the wastewater is transported to treatment plants via the wastewater pipe, but to prevent flooding and sewer backups, some of the rain and wastewater mixture is diverted to overflow into the river.”
In other words, the water treatment centre can only handle so much, and the rest gets dumped in the river. Yep, that same river where Ottawans go to swim and enjoy the brief reprieve of Ottawa summer.
The city has developed the Ottawa River Action Plan, which includes a plan to build more storage space beneath the city to hold contaminated water until it can be fed into the wastewater treatment centre, but this major project is stalled as the city waits for $100 million in provincial and federal funding to come through to make it all happen. (For more on this issue, check out Ottawa Magazine‘s 2011 interview with Ottawa Riverkeeper Meredith Brown.)
So what do we do in the meantime? The Urban Hippie picked the brain of Ecology Ottawa’s policy coordinator, Trevor Haché, to see what he thinks. He says “there are other things that the city can and should be doing.” Here are three of them:
According to Haché, Ottawa needs a green roofs bylaw, like the one Toronto has implemented, stat. It would see the city require these roofs, which generally mean a roof that is partially or completely covered with vegetation and a growing medium, planted over a waterproofing membrane, on all new building development. Green roofs absorb rain water, and have the added bonus of being useful for growing food and providing habitat for ecologically and imperative but embattled bees. They also create a layer of insulation that keeps the building cooler in the summer and warmer in the winter.
Soak it up
The city should create more permeable surfaces such as roads and sidewalks, Haché says, which would absorb rainwater instead of letting it stream off the current surface structures, where it is captured by the failing sewer system. “We need to do a much better job of creating surfaces that are permeable, that allow things to soak into them,” says Haché, “so when the city’s upgrading a sidewalk or road, they don’t have to build sidewalks and roads like we’ve been building them in the last number of years, which is basically a flat surface that’s totally impermeable. There are cities that are starting to experiment with green infrastructure — creating green spaces along roadways or sidewalks that hold water better.”
Haché says the creation of wetlands near where overflow releases into the river (and there are 18 sites where this generally occurs, according to the city) would allow the water to be filtered and cleaned naturally, and could be much, much cheaper than the new system the city is currently planning.