Western Canada: Torrential rain prompts flood fears in Calgary, nine years after disaster

Good morning. It’s James Keller in Calgary.

Almost nine years ago to the day, heavy rain was drenching Calgary and much of southern Alberta, with more than 200 millimetres falling on some places in less than two days.

The Elbow and Bow rivers, which slice through Calgary and meet just east of downtown, swelled from a combination of the rain and melting snowpack. The Elbow eventually overflowed, leading to catastrophic flooding throughout much of downtown that caused $5-billion in damage and killed five people throughout the region.

Calgary has once again been experiencing torrential rain and there have been rainfall warnings across the region. The predicted amounts have been lower – 150 millimetres spread over three days – and no one is expecting anything close to a repeat of 2013, but officials have been emptying reservoirs, building berms and taking other measures to prepare for the potential of flooding.

The City of Calgary declared a local state of emergency on Monday, which Mayor Jyoti Gondek said was a precautionary measure that gives local officials additional powers. She added that those powers wasn’t needed yet. The city and the province have said they have learned much since 2013 and nearly a decade of flood-mitigation work has left the city far better prepared.

A long stretch of Memorial Drive, a heavily travelled east-west corridor that hugs the Bow River just north of downtown, was shut down to allow crews to build a temporary berm to control potential flooding. The city has closed Prince’s Island Park and St. Patrick’s Island along the Bow River and have urged people to stay off the rivers for their own safety.

Ms. Gondek said on Tuesday afternoon that the weather forecast had improved somewhat and less rain was expected than initially feared.

Francois Bouchart, the city’s director of water resources, said the rain was tapering off on Tuesday and appeared to be slowing, with the amount of rain tracking less than predicted. He also said some of the rain that was expected west of Calgary in the mountains instead fell as snow, which means it won’t dump directly into the rivers.

He said he was optimistic that the city won’t see localized flooding, much less the sort of catastrophic flooding that deluged the city in 2013.

The heavy rain has been a reminder that Calgary still remains vulnerable to extreme flooding from its two main rivers, and also that the city still does not have the most significant piece of infrastructure that was planned after 2013.

The provincial government spent years considering how to protect the city from future flooding and eventually settled on a reservoir project in Springbank, 15 kilometres west of the city, that will be able to divert water from the Elbow River.

But the project has faced multiple delays and construction only started last month. Its budget has ballooned to $744-million after it was earlier pegged at $432-million. It won’t be ready until 2025.

This is the weekly Western Canada newsletter written by B.C. Editor Wendy Cox and Alberta Bureau Chief James Keller. If you’re reading this on the web, or it was forwarded to you from someone else, you can sign up for it and all Globe newsletters here.