Montreal to build new ‘sponge park’ to absorb rainwater

Montreal city officials are planning a major landscaping  project along a long stretch of grass wedged between a bike lane next to the Atwater filtration plant and a street in Verdun.

Authorities want to build a so called “sponge park,” a natural green space made up of ponds, vegetation and other porous material that allows rainwater to pass through the ground naturally and be absorbed into the water table.

The new landscaping is designed to ease the burden on the city’s underground water infrastructure network that often can’t handle large quantities of water during major rainstorms, leading to flash flooding.

“When there’s a lot of rain falling, even all the pipes cannot hold it, it’s too much,” Montreal Mayor Valérie Plante said at a morning press conference.

This new sponge park is the latest planned of 30 the city wants built during the next two years.

“We give a break to our infrastructure when there is a heavy rain,” Marie-Andrée Mauger, Verdun borough mayor, told Global News.

1:55 Montreal to invest in sponge infrastructure to mitigate impact of flooding

This project is expected to cost more than $16 million, but one expert says it’s a lot less expensive than rebuilding the underground water infrastructure.

“Digging up the road and making a bigger pipe is really expensive. It’s much cheaper to make these sponge parks,” Susan Gaskin, a professor of Environmental Engineering at McGill University, told Global News.

China has several sponge cities in highly urbanized areas that Gaskin says perform very well.

“They have very large problems with peak floods and so they’ve realized putting ponds back into the landscape is very, very useful,” she said.

Work on Montreal’s latest sponge park is slated to begin in the coming weeks and should be finished by the end of 2025.