Edmonton city councillors want to 'crunch the numbers' to find the cheapest option when it comes to dealing with flooding: Do the work up front, or pay for the cleanup later? 

The question was discussed as councillors were given an outline of the city's flood mitigation strategy at the utility committee meeting Friday.

The strategy includes scenarios where the city could spend between $2.2 billion and $4.68 billion to improve the city's drainage system, depending on the level of risk it wants to guard against.

The scenario city staff recommended involves paying $2.6 billion to bring the city's drainage system to a standard where it could handle a one-in-100 year storm.

Mayor Don Iveson introduced a motion that calls for the city to partner with the provincial and federal governments, and insurance companies, to study the data and numbers.

ben henderson

'I think we have to pay one way or the other,' says Coun. Ben Henderson on flood prevention. (Lydia Neufeld/CBC)

When there is flooding, it is often those levels of government that end up paying for disaster assistance, said Coun. Ben Henderson.

The committee voted in favour of the motion.

"I think we have to pay one way or the other," said Henderson. "There's a point at which it may be cheaper to do the repair afterwards than to guard against something from a risk point of view that's very unlikely to happen."

'The new normal'

There is probably a compromise somewhere in the numbers, said Iveson.

"Do we want to pay through our drainage utility or do we want to pay through our utility rates? Because there's probably an overlap point there that's the sweet spot," said Iveson.

"What extreme do you actually plan towards?" asked Henderson. "Somebody needs to crunch those numbers before we start making these decisions."

The plan recommended by staff would protect Edmonton homes and businesses against what has been described as the new normal for the city.

The new normal as defined by city staff includes storms that cover only a small area — five square kilometres or less — and can quickly overwhelm sewer lines in older areas, flooding basements and road underpasses," said Todd Wyman, director of sustainable services.

That type of small storm flooded 4,000 basements in Mill Woods in 2004. A similar storm flooded 1,200 basements in 2012, said Wyman.

EPCOR is taking over the city's drainage department in September 2017.

The city-owned company will continue with this flood mitigation strategy and bring forward a list of priorities to the committee in 2018.