Lessons learned: Manitoba government likely to improve flood protections

It will be weeks before flood waters fully recede in Manitoba, but once they do, the province is likely to spend millions of dollars to try to flood-proof areas along the Assiniboine River as much as possible.

Manitoba has been here before.

In the years following the 1997 "flood of the century" in the Red River Valley, roughly $1 billion was spent in federal and provincial dollars to expand dikes, improve ditches and build up other defences.

Now, the provincial government says, it’s time to look at improvements along the Assiniboine to the west.

"When we’re (done) dealing with the day-to-day challenges, job No. 1 will be to sit down and look at the lessons of the flood and see where we can make a difference," Emergency Measures Minister Steve Ashton said this week.

"You start the process almost immediately as you finish with the flood."

The government often talks about "97 + 2" in the Red River Valley – a term referring to a federal and provincial effort that saw homes, businesses and community ring dikes built up at least two feet (60 centimetres) higher than the record water level in 1997.

More recently, the vast channel that diverts the Red around Winnipeg has been expanded and homeowners in the most flood-prone areas north of the city have been forced to move.

The result has been that even in very bad years, when the Red becomes a lake 16 kilometres wide in some areas, the vast majority of homes and businesses remain dry. Farmland and roads are flooded, but residents are safe.

Along the Assiniboine, defences are also generally built up two feet higher than the area’s last big flood of 1976. But this year has set a new record. Officials call it a once-in-300 year flood that has swamped farmland, forced the evacuation of low-lying areas in Brandon – the province’s second-largest city – and prompted the government to plan for a deliberate release of water near Portage la Prairie to prevent heavier uncontrolled flooding downstream.

Prime Minister Stephen Harper said this week he was willing to help pay for new flood prevention subject to talks with the provinces. Ashton said he already has some ideas in mind.

"We’ve seen what’s worked thus far. Building up the Assiniboine dikes … may be something we can look at doing, to further work on those dikes."

Other potential upgrades could include expanding the Shellmouth dam and reservoir, which takes water from the upper Assiniboine in Saskatchewan and releases it downstream in controlled amounts.

There is also the Portage Diversion, a man-made channel that takes water from the Assiniboine and funnels it to Lake Manitoba to the north.

Manitoba’s dikes, diversion channels and reservoirs have been built with one idea in mind: floods will happen – due to water that comes from as far away as the Rocky Mountains or North Dakota – and the best method of protecting a reasonably flat landscape is to keep the water moving, divert it around communities and homes and push it through to the province’s big lakes farther north.

In Brandon, where dikes made of dirt and supersized sandbags stacked three metres high are the only thing preventing the city’s valley from being swamped, officials are also thinking of improvements that could include raising roads or enlarging permanent dikes.

In the last two decades, Brandon has allowed shopping centres and new housing to be built in one of its lowest-lying areas. The Assiniboine River has, for many days, run higher than that area. Crews have been inspecting and maintaining the levees that protect the neighbourhood around the clock.

"What we will do is have a complete review of this event and make some solid decisions about what we will do to withstand another event similar to this," said Brian Kayes, the city’s director of emergency services.