Torrential downpour floods streets across London Monday morning

Adelaide Street underpass, Oxford Street West among areas closed because of flooding

The much-celebrated Adelaide Street underpass looked more like a drainage pond Monday morning, one of many roads and streets that flooded during a sudden heavy downpour that hit the region.

CBC: Drivers navigate through the flooded intersection of Waterloo Street and Pall Mall Street in London, Ont., on Monday, July 15, 2024. (Andrew Lupton/CBC)

Drivers navigate through the flooded intersection of Waterloo Street and Pall Mall Street in London, Ont., on Monday, July 15, 2024. (Andrew Lupton/CBC)

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"Heavy downpours can cause flash floods and water pooling on roads," Environment Canada said in a severe thunderstorm warning posted to its website. The agency said to expect about 40 to 60 mm of rain.

The skies grew dark and heavy rains began at around 9 a.m., falling for about two hours.

Some parts of the city got 7.5 mm of rain, said Ashley Rammeloo, the city's director of water, wastewater and stormwater. "What we're seeing is localized flooding, and the local storm system needs time to drain away."

Flooding triggered several calls to emergency services across the city, and a reminder for Londoners to report flooding through the city's website, not to 911.

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The London Fire Department responded to several alarms to ensure there was no smoke, fire or other weather/water related hazards, a spokesperson said.

The City of London closed several portions of roads that were under water, including Oxford Street West near Mud Creek, between Wonderland Road and Beaverbrook Avenue, as well as the Adelaide Street underpass.

Commuters welcomed the $87-million Adelaide Street underpass when it opened last spring after two years of construction to help drivers avoid the train crossing in the location.

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This article was originally published for CBC News.