Flooding by design

‘Sponge ground’ proves how Toronto can build flood resiliency

- PATTY WINSA

Workers repair a children's garden at Evergreen Brick Works after heavy damage from flooding last month.

When the Evergreen Brick Works flooded during a major storm last month, it wasn’t just the intense rainfall that overwhelmed the site.

Instead, the Don River overflowed onto the floodplain, covering the site with more than a metre of water, including raw sewage which had been diverted into the river from combined stormwater and sewer overflows.

As devastating as that flood has been for the popular park and nature centre across the river from the Don Valley Parkway — it was by design.

When the Brick Works site on Bayview Avenue was redeveloped from an old industrial site, it was remade into a “sponge ground,” with naturalized areas as well as man-made features to help absorb and filter water from the Don, reducing the risk of floods like what the city saw on July 16.

For Evergreen, the non-profit behind the Brick Works, the site is an example of how Toronto and other cities can build flood resiliency into parks and public spaces. As for the record storm, which unleashed nearly 100 millimetres of rain in three hours on the city, “the issue was the pace and scale. It happened so quickly,” said Evergreen CEO Jen Angel.

The water “just went like this,” she said, raising her arms parallel to demonstrate the floodwaters, which reached an unprecedented 4 1⁄2 feet.

The cleanup, which is “nasty and ongoing,” is estimated at $2.5 million.

Despite the damage, the fact the Brick Works made it through the storm as well as it did shows its sustainability efforts are not only working, but could be applied to the rest of the city as it faces the challenges of climate change.

“The flood came in and then the site did what it was supposed to do. And spit it back out,” Angel said in an interview at the site last week.