'We could take it': Manitoba better braced to face a 1997-level flood, experts say
'I wouldn't say that we wouldn't break a sweat, but I think we could take it'
As Manitobans build sandbag walls and watch riverbanks vanish under ever-swelling water levels, ghosts of the 1997 flood of the century have returned exactly 25 years later.
But this time around, experts say the province is on more solid ground.
"No doubt there would still be a lot of work associated with it. But there's no question we are in a better position than we were in '97," said Russ Andrushuk, assistant deputy minister for Manitoba Transportation and Infrastructure.
The same confidence is expressed by University of Manitoba civil engineering Prof. Jay Doering, an expert in hydrology who worked with the Manitoba Floodway Authority during the 1997 deluge and later on the floodway expansion committee.
"If a 1997 flood were to occur again, I wouldn't say that we wouldn't break a sweat, but I think we could take it and there really wouldn't be any reason for significant concern," he said.
This spring could test that theory. Communities along the Red River Valley are being told a major-level flood is almost a certainty.
On Friday, provincial flood forecasters said the coming flood could approach the volume of the 2009 flood, which was the highest since '97.
Manitoba has been pounded by one snowiest winters on record and by four significant precipitation systems in April alone. The third Colorado low in as many weeks is headed into the province this weekend, bringing 30-80 millimetres of rain to southern Manitoba.
Last weekend, a similar system inundated Winnipeg with 50-70 millimetres of rain and even more to the south, including in the United States, on land that feeds into the Red River and its tributaries.
"We're going through a little bit crazy weather this year," said Fisaha Unduche, executive director of Manitoba's hydrologic forecast centre.
Manitoba has received 200 to 500 per cent of normal precipitation for April, when there's typically 28 mm, Unduche said.
"Most creeks and rivers are already full with the previous system and the snow melt," and the ground is saturated, he said. "This precipitation could just add more water into the system."
The Red's swollen crest is now predicted to arrive in Manitoba in mid-May.
When the '97 crest arrived, more than 22,000 people had been chased out of about 20 communities along the valley, turning them into ghost towns, save for those designated to keep watch.
At its height, the Red was the largest river in North America, covering 1,840 square kilometres of land. At its widest, the murky north-flowing tide measured 42 kilometres from west to east.
That flood was a wake-up call, Doering said.
Many of the flood protections in place had been designed for a one-in-100-year flood, set in place following the devastating 1950 event.
But climate change has made for wetter years and more regular floods and altered the outlook that was used to design the original Red River Floodway, Doering said.
The floodway, a 47-kilometre channel between St. Norbert and Lockport that runs along the eastern edge of Winnipeg, diverts some of the Red's flow to maintain a manageable river level in the city.
At the time the second-largest earth moving project in the world (second only to the Panama Canal), it was built between 1962 and 1968 and has been credited with saving the city from major floods 20 times.
Since it was created, most floods within city limits have involved river levels just below 20 feet above normal winter ice levels — with the exceptions of 1997 (24.5) and 2009 (22.6).
Without the floodway, the 1997 crest would have been 35 feet above normal winter ice level at James Avenue in downtown Winnipeg, the province estimated.
Peak levels this spring are expected to be around 20 feet James.
When the floodway was built, it was heralded as being able to accommodate a water capacity forecast to occur every 160 years.
"When we ran the statistics in 1997, we realized it could carry a one-in-100-year flood. In fact, it was probably closer to about one in 90 years or even a little less than that," Doering said.
Following the '97 flood, the province embarked on a 10-year, $627-million expansion of the floodway. It is now rated at a protection level for a one-in-700-year flood.
In addition to the floodway expansion, changes in the past 25 years include properties in the Red River Valley being raised.
Older developments are protected to a one-in-100-year flood level and newer developments must be at a one-in-200-year flood level — approximately a '97 level plus two feet.
"Since 1997, we've actually learned a lot," Transportation and Infrastructure Minister Doyle Piwniuk said during a recent flood update.
Highway 75, a primary link between Manitoba and the United States, has been raised in several key areas by about 1.2 metres so that it can withstand higher levels of water — though not quite '97 levels.
Highway 75 will most likely be closed for a while this spring, Piwniuk said.
The cost of raising it all above '97 levels would have been prohibitive, so the province decided instead to build a detour. Provincial Road 246, between Morris and Aubigny on the east side of the Red River, has been upgraded from gravel to asphalt "to the highest loading standards" in order to protect the major trade route, Piwnuik said.
There are also eight more community ring dikes along the valley for a total now of 16 — and all meet the one-in-200-year flood level protection.
There have been significant enhancements as well to the City of Winnipeg's pumping structures and the hydroelectric network to provide better monitoring of river levels, Doering said.
A flood management protocol manual has also been written, clearly outlining the roles everyone has to play, like a pro sports playbook.
Since the 1997 flood, more than $1 billion has been spent on flood mitigation efforts in Manitoba, preventing more than an estimated $7 billion in damages, the province's hydrologic operations website says.
"I work with my counterparts across Canada, and we can be proud to say that Manitoba is always well-protected when it comes to floods," said Unduche.
"The chance of having property damage or those kinds of issues in Manitoba will remain very rare."
That said, it's still no walk in the park to defend against a flood, said Andrushuk: it requires a massive co-ordination of efforts to initiate emergency plans.
"It's all hands on deck. We start our preparation for spring flooding every year in January, with a lot of agreements for contracting services, engineering services, materials and equipment," he said.
Much of that is behind-the-scenes work, but there are still impacts the public cannot escape, such as the closing of ring dikes, which encircle entire towns and eliminate the freedom of residents to come and go.
"Even though the communities aren't as affected they used to be, they still are in some ways," Andrushuk said.
WATCH | Protecting Winnipeg from a one-in-700-year flood: Original floodway versus expanded one
While we've become better at withstanding the spring onslaught from Mother Nature, that process must never end, Doering said.
Hydrology statistics and strain on infrastructure is something governments and municipalities must keep an eye on as climate change continues.
And it's equally important to ensure the infrastructure can actually do what everyone expects, he said.
"We can't just build these things and assume that they're going to protect us for the rest of our lives."
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