Should Edmonton upgrade its drainage system to protect against the storm it’s seen already, the storm it expects to come, or the storm that’s technically possible?

That’s the question city councillors wrestled with at council’s utility committee Friday as they struggled through a flood mitigation plan that could cost between $2.6 billion and $4.7 billion depending on the level of protection.

“Is that better shared with the insurance industry as a long-shot risk?” said Mayor Don Iveson, suggesting some scale of flood simply isn’t worth the infrastructure cost to protect against.

“What is the sweet spot?” said Iveson, suggesting Edmonton residents either pay through utility rates for major infrastructure projects or through their own insurance plans.

“We have to pay one way or the other, I think. But there’s a point at which it might be cheaper to do the repair afterward,” said Coun. Ben Henderson, saying he’s interested in getting to a good level of protection quickly, but not ready to commit to going all the way. “Someone needs to crunch those numbers before we make these decisions.”

Disaster plans

Councillors voted to try to work with federal and provincial partners to study the issue together. If homes, businesses and city infrastructure floods, often those orders of government are the ones who end up paying through disaster assistance.

It makes more sense for them to struggle with this questions, said Henderson, because “we’re not actually liable to foot the bill when this fails.”

City officials have finished a study of 160 residential and 33 industrial neighbourhoods built before the 1980s. These neighbourhoods were built to a lower flood protection standard and will flood when an intense, local storm hits part of the city.

The $2.6 billion infrastructure plan would bring these neighbourhoods up to the same standard of protection new neighbourhoods enjoy. That means they would be protected against the type of storm-related flooding Edmonton’s already experienced, but not the type of storm experts expect climate change could make possible.

Yesterday’s flood

The $2.6 billion plan would protect against the type of storm that hit Mill Woods and parts of southwest Edmonton in 2012, flooding 1,200 basements. That time, the province paid out roughly $32 million in disaster assistance. That was in addition to $105 million in insurable damage.

Edmonton’s drainage work is transferring to Epcor in September. The city-owned company will be coming back to council with a prioritized list of projects under that $2.6 billion plan in 2018. At that point, it should also have a better sense of available federal grants and the impact this building campaign will have on utility work.

Officials previously suggested spending $60 million a year would get the work done in 44 years; the timeline could be cut in half if the pace of investment is doubled. Each project would be designed so capacity could be easily expanded if the city later decides it needs to protect against a much more severe storm.

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