How Toronto’s plan for the Don River shifts Ontario’s approach to waterways

By John Michael McGrath - Published on July 23, 2015
Don River renaturalization
Projection of Waterfront Toronto's plans for the Lower Don River

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Toronto’s complicated relationship with the Great Lake on its southern edge took another baby step forward last week, as representatives of all three levels of government announced the start of a $5-million consultation that will, if all goes well, open the door to a renaturalized mouth of the Don River where it meets Lake Ontario.

For years, Waterfront Toronto, an agency funded by three levels of government, has been planning the eventual renaturalization of the Don River to better control flooding and open the city’s moribund industrial lands for development.

It’s hoped that Toronto will lead the way on a problem faced by other cities around the Great Lakes, and around the world: what to do with shores built around industry after the industry disappears.

“Not many people want to live next to an urban river in their current state, when they're filled with garbage and shopping carts,” says Alex Brunton, a practice leader with Baird & Associates, a firm that specializes in coastal engineering. Rivers that were paved or drained to make them more amenable to industry in the early 20th century – such as, Toronto’s Don River – would need to be revived one way or another.

(While all three governments were present at the announcement, only the City of Toronto is actually putting up the initial $5 million.)

So, why redesign the urban rivers of the world with such a heavy emphasis on the natural features that were obliterated a century ago? Because, according to Brunton, our understanding of their role in the city has changed.

“We really know that encasing rivers in concrete doesn't work, and it can exacerbate all of the flood problems down-steam,” Brunton says. From their sediments to their shores (and the water in between), rivers are complex systems that are more resilient to changing conditions than engineers once thought.

While removing vegetation from river basins was seen as a way of reducing flood risks last century (because dense vegetation was blamed for obstructing the flow of water out from flood zones), more recently engineers have come to appreciate the roles that vegetation plays in preventing flood damage, for example by controlling the sediments in the river.

“So if you remove the vegetation in the river it may lower flood levels in the short term, but it can actually cause more issues in the long term,” says Brunton.

But the long term catches up to all of us eventually. With a changing climate Toronto can expect increasingly severe summer storms, and has already seen what harsh weather can do to the Don. In 2013, Toronto beat Hurricane Hazel’s one-day 1954 rainfall record and the flooding was enough to strand a GO Train and force its evacuation.

Chris Glaisek, vice-president of planning and design at Waterfront Toronto, says while the costs of the renaturalization are daunting, putting the flood-proofing infrastructure in the Lower Don River will serve multiple purposes.

“The challenge with the flood protection is that the cost is pretty much the same wherever you put it. So if you’re going to do it, are you going to put it in a place where it does just one thing, or where it also stimulates new development?”

Glaisek contrasts the renaturalized Don with the existing concrete-and-landfill of the Keating Channel.

“Things like the Keating Channel are single-purpose pieces of infrastructure, and we just don't do things like that anymore, partly because we can't afford it anymore.”

There’s a tradeoff for the resiliency and multiple uses that engineers say a naturalized Don mouth will bring: the green space is costly and will occupy a lot of land that would otherwise go to new homes and businesses. That’s just one of the factors planners will have to balance in what everyone acknowledges will be a decades-long plan.

“We're looking at 30 to 35 percent of the land being used for open space and river, with 65 per cent being used for development,” says Glaisek. “That's what you see in projects around the world right now, going back to Battery Park City. I think the balance is right, but there are always differences of opinion.”

“Can I say in 200 years that everyone will be happy? Probably no, but it will be a much more cohesive approach,” says Ken Dion, senior manager with the Toronto and Region Conservation Authority. “For example, maybe we design for one species of fish or bird, but even if those species don't thrive some species will.”

One species in particular still occupies the Lower Don pretty tenaciously: the handful of industrial companies whose businesses are still there. That includes companies like Lafarge, whose concrete feeds the GTA’s condo boom; and Redpath Sugar, which feeds the food processors in western Toronto.

Large industrial plants don’t always live harmoniously with the dense residential neighbourhoods the city has planned for the Port Lands. Whether it’s abattoirs and candy factories in Toronto’s west end or a concrete plant in Etobicoke, industry has a hard time mixing with new neighbours.

That’s not just a problem Toronto faces: all across Ontario manufacturing jobs are moving for cheaper land or simply disappearing altogether. While cities obviously hope to attract new residents and businesses to replace the jobs they’ve lost, even success has its problems. How do cities welcome in the kind of new people that will keep the future vibrant without losing their grip on the past?

Glaisek says Waterfront Toronto is trying to plan in such a way that companies like Lafarge and Redpath won’t be pushed out of their current homes. Still, if the agency succeeds as planned eventually real estate values around the waterfront will climb to the point where the last vestiges of the Big Smoke will cash out and sell their property to developers.

“People had a very different attitude towards nature and cities than we do now," he says. "We're just starting to embrace nature in cities in a different scale than we used to. This is going to be a defining project for Toronto."

Image credit: waterfronttoronto.ca

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