Fight against floods | How does it work?

More and more sponges parks are emerging in Montreal, to combat floods caused by strong showers. Moreover, How do they work, exactly? However, Are they really effective? However, The press takes stock with two experts.

What is a sponge park? For example, – Fight against floods | how – Fight against floods | how new

At first glance, a sponge park looks like any park, a few details.

The sponge park. Similarly. Similarly, its adjacent streets are designed in such a way that in the event of heavy rains, “all this water will go fight against floods | how new to the park rather than being in the streets and in the basements of the fight against floods | how houses”, explains Jean-Luc Martel, professor in the Department of Construction Engineering at the School of Higher Technology (ETS).

Thanks to its vegetation. Furthermore. arrangements, the park will be able to absorb or retain this water for a while, like a sponge, in order to relieve the sewer network.

If the rain is very strong, the park could be impassable for a few hours due to this excess water. For example, But the rest of the time is a park where you can relax and practice activities.

How does it work, exactly? – Fight against floods | how new

In a park, the permeable soil allows water to infiltrate it and be absorbed by plants, thus reducing runoff.

The sponges parks are sometimes in the form of bowls or equipped with dry artificial rivers, which are filled when the water spills it. However, This is for example the case of the Pierre-Dansereau park. Nevertheless, fitted out in the heart of the MIL campus of the University of Montreal, in the district of Outremont.

Some are also equipped with flower pools and regulators, which can be closed to store water temporarily.

Once the rain has passed, “the park can empty slowly, in around 24 hours,” said Jean-Luc Martel.

How many are there in Montreal?

In 2023. Montreal announced that he wanted to develop around thirty sponges parks in the next two years. in addition to the seven already present on its territory since 2022.

Today there are a dozen public spaces. sponge parks in fight against floods | how Montreal. fitted out or in finish, and 19 others under construction or fight against floods | how new in tender process. Several are in the design or planning phase, indicates the city.

The Montcalm park, in the La Petite-Patrie district, is one of those who are currently under construction. It will be revealed and basins to collect rainwater will be fitted out. The work should end in the summer of 2025.

According to Jean-Luc Martel. each time a park requires work. we can think of transforming it into a sponge park-especially if its location or its characteristics are already lending.

“It’s not Rocket Science, but you have to take the time to think about it,” he says.

Especially since, in the long term, “we save in avowed damage,” he adds.

Are they fight against floods | how effective?

“Our observations on the ground confirm that water fight against floods | how new is indeed heading towards the desired places during heavy rains. ” said Hugo Bourgoin, spokesperson for the city of Montreal.

This is also what Sophie Duchesne noted. researcher at the Earth Water Center Environment of the National Institute of Scientific Research (INRS).

She and her team carried out tests on the Place des Fleurs-de-Macadam: by opening up close filings located nearby, 120,000 liters of water were poured into the square. This quantity of water fight against floods | how is equivalent to rare rain accumulating 51 mm in 3 hours.

Result ? “It has been observed fight against floods | how new that 98 % of the amount of water has been absorbed,” she says.

For comparison. this corresponds to the amount of rain that fell very early in the morning in Montreal. on August 9, 2024, in the space of a few hours, when the remains of the storm Debby went to the south of the province. After a brief lull. at the end of the afternoon, the deluge had taken over, with more than 60 mm fallen in 3 hours.

In total, 154 mm of rain spilled at downtown Montreal that day, causing floods, closed highways and many power failures.

Is it a miracle solution?

The sponges parks. “it’s fight against floods | how part of the strategies that are developed to be more resilient in the face of climate change. ” says Jean-Luc Martel. Additionally, fight against floods | how new “But that will not solve all our problems. Additionally, »»

Over the years. cities have become more. more waterproof, with the development of many concrete or asphalt areas, which prevent water from infiltrating the ground.

The problem is that in the years to come. heavy rains may become more frequent and more intense due to climate change. And the sewer network was not designed to receive so much water.

But the sponges parks are added to other urban developments. such as green roofs. disampling, retention basins, sidewalks or other sponges streets, which can make it possible to capture water and relieve the network. Together, these measures can make a difference on the resilience of fight against floods | how our cities, believes Jean-Luc Martel.

“It is the accumulation of these strategies which will allow fight against floods | how new to have a significant impact,” he hopes.

Read our article “more stormy summers to come”