Quebec officials warn of possible dam failure, forcing evacuation of 250 people –

Quebec officials warn of possible dam failure, forcing evacuation of 250 people -
Ottawa declares state of emergency as water keeps rising
Were going to see more and more of these extreme weather events more regularly, Justin Trudeau said.

Canadian Forces personnel sandbag a house against the floodwaters Thursday in Laval. Ryan Remiorz / THE CANADIAN PRESS

Environment Canada earlier on Thursday issued a special weather statement warning of “significant rainfall” in the Ottawa area totalling 20-35 millimetres between Friday morning and Saturday morning. This heavy precipitation coupled with the spring snowmelt has the Ottawa River Regulating Committee forecasting peak floods reaching 11 centimetres above 2017 levels in the Britannia/Lac Deschenes area on Sunday.

During his Sunday tour of Île Bigras, a picturesque Laval community in the middle of Rivière des Prairies that’s been flooded twice in the last three years, Premier François Legault said Quebec was going to have to rethink its compensation strategies given the increasing frequency of flooding events caused by climate change.

“We’re going to see more and more of these extreme weather events more regularly,” Justin Trudeau said.

As recently as Wednesday morning, city staff felt they had enough resources to cope with the rising water levels along the Ottawa River — but, with the new forecasts, the flooding situation changed “almost in the blink of an eye,” city manager Steve Kanellakos told reporters.

As Quebecers grapple with another disastrous season that has flooded 1,900 homes so far, only two years after water levels rose to historic levels and flooded out more than 5,000 residences, there is a common perception that the frequency and severity of flooding events has increased significantly over the last decades.

We cant access the buildings, we cant run our programs. We cant put our docks in, said McKenzie who has served as Ottawa Rowing Clubs executive director for three years. We love the river, it really is our playground; its our happy place, but were at its mercy and right now its pretty crippling.

Backing that perception up with hard figures is difficult, however, due to a lack of historical data and the extreme swings seen in natural variability.

Melissa McKenzie is concerned about the launch of Canadas oldest rowing club. Founded in 1867, Ottawa Rowing Clubs season is in doubt amid disastrous flooding along the Ottawa River. Flood waters continue to rise with more rainfall in the forecast.

For instance, explains Daniel Henstra, a University of Waterloo professor specializing in flood-management policies, and a fellow at the Centre for International Governance Innovation, a so-called “100-year flood” refers to a flood the magnitude of which has a statistical probability of occurring once every 100 years, or, in other words, has a 1 per cent chance of occurring in any given year. Since the probability is the same from year to year, it is possible for a community to experience such a flood in two consecutive years.

What used to be the parking at the club is now flooded, signs overturned, floating docks beside them. Trailers were moved, much of the equipment including the 90 boats inside the buildings were raised to mitigate flood damage.

“Due to a lack of available (longitudinal) data, it is practically impossible to know whether the frequency of these ‘100-year floods’ has increased in Canada,” Henstra said. “Although it would seem that way, given the number of events we have been experiencing, we don’t have sufficient, convincing evidence that these events are actually becoming statistically more likely.”

"A dam like Bell Falls is designed to withstand a flood that happens once in a thousand years," said Simon Racicot, head of production at Hydro-Québec. "Today at noon we reached that level, and at that point there's a protocol in which we notify civil security and residents of imminent danger."

Ottawa declares state of emergency due to flooding

Add to that the fact it’s difficult to separate climate change effects from natural variability. Quebec has experienced several devastating inundations in the past since all rivers flood at some point as part of the natural life cycle of a river, said Pascale Biron, an expert in river dynamics and professor in Concordia University’s department of geography, planning and environment. The Canadian Disaster Database run by Public Safety Canada records that Quebec has suffered several major flooding events over the last decades. They include one in the Saguenay region in 1996 that forced the evacuation of 15,825 residents, and another in 1998 in eastern Ontario and Quebec that evicted 3,757 from their homes. In 1974, major flooding ravaged the Maniwaki region.

But whether there are more frequent, severe storms now than in decades past is hard to tell, Biron notes, because there are not many gauging stations in Quebec that have long historical records, and the way flood levels are measured has evolved technologically, so it’s not always possible to compare discharge levels from the 1930s with those from the 2000s. At the same time, changing land use from forested zones into urban areas can also have a major effect.

“Unfortunately the science is just not good enough to attribute a particular local extreme weather phenomenon to climate change, particularly in a data-poor country like Canada,” Henstra said.

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What scientists have concluded is that most climate change models predict more frequent extreme precipitation events in the future, Henstra noted, which could lead to more river flooding, as well as urban flooding and coastal flooding as sea levels rise.

“You’re going to see more firefighters, you’re going to see more police officers and more municipal workers to help for floods that could come this weekend,” said Martin Guilbault, operations chief of the Montreal fire department.

“Overall (not just in Quebec), scientists believe that events that were on average occurring once in 20, 50 or 100 years, may occur more frequently in the future because warmer air is able to hold more moisture, so perhaps a 50-year flood will become a 40-year flood in the future,” Biron said.

“They told us that there was no time to pack our bags and that we had to leave because the dam was maybe going to break,” Denise Audet said. She said everything happened so quickly she “didn’t have time to be scared.”

“I think what is safe to assume is that the climate will become more unpredictable in the future, so we need to prepare for flood events that we have not seen yet, realizing that the natural variability will always remain, but the amplitude of the changes will likely increase,” Biron said.

Ottawa declaring state of emergency in response to flooding; calling for military and provincial help

The inability to present hard data can be frustrating for researchers who note it makes it more difficult to convince Canadians to pay now in order to prevent catastrophes in the future.

“Police are using all the means at their disposal to ensure people’s safety,” said the Sûreté du Québec on Twitter. “We ask residents of the areas affected by forced evacuations to co-operate with the authorities.”

In its overview of climate change nationally, Natural Resources Canada wrote that national trends in precipitation are difficult to assess largely due to the fact it comes in different states (rain, snow, freezing rain) and differs largely by region.

“Even if this dam fails completely, it would have no effect on the Outaouais [Ottawa] River,” he said. “So really, it’s an isolated situation and has no impact on our other installations.”

“Nevertheless, Canada has, on average, become wetter during the past half century, with mean precipitation across the country increasing by about 12 per cent,” the overview finds.

Guilbault said there are 23 residences and 38 cottages in the evacuation zone along the river. Quebec provincial police tweeted they were helping about 250 people get clear of the affected area as a preventive measure.

In Quebec, government ministries base their strategies and actions on studies published by scientists and researchers in the domain, said Louise Quintin, a spokesperson for the province’s ministry of public security. After the 2017 floods, Quebec ordered the creation of costly flood maps for the whole province by the end of 2020, after decades of going without.

"We are confident that the structure is solid," Racicot said. "But the protocols force us to warn people of the danger. We are entering into an unknown zone right now — completely unknown."

In Quebec, the combination of science and repeated, heavily publicized flooding events occurring in rapid succession appear to be shifting government attitudes.

Public Security Minister Genevieve Guilbault told reporters Thursday evening the province's hydro utility is confident the dam can hold back its current water reservoir and is structurally sound.

The City of Ottawa has declared a state of emergency as river levels continue to rise, threatening to surpass those reached when flooding devastated some neighbourhoods two years ago.

This morning, a special weather statement from Environment Canada came into effect, calling for significant rainfall on tomorrow. To help City crews, volunteers and residents in affected areas, I am declaring a State of Emergency and requesting help from the Province and army.

We can no longer do it alone.- Ottawa Mayor Jim WatsonEnvironment Canada has issued a special weather statement predicting up to 35 millimetres of rain by Saturday morning, and river authorities are now forecasting that in some areas, the water could rise up to 11 centimetres above peak levels reached in May 2017.

I will be travelling to Ottawa first thing tomorrow morning to meet with the mayor and city officials, tour the areas impacted by the flooding, and meet with residents to ensure theyre getting the support they need from their provincial government, Ford added.

Watson said he's also asked for help from the Canadian Armed Forces, and has been told 400 troops will be deployed to key areas.

On Thursday, Ottawa Mayor Jim Watson formally notified the Ontario government, and the city said it is formally requesting financial assistance and additional resources on the ground to support city staff.

Ontario Stands with the City of Ottawa

"We can no longer do it alone," Watson said. "We are now beyond our city's capacity, and that is why we have called in the Armed Forces."

City manager Steve Kanellakos said the city felt prepared until the latest forecast from Environment Canada.

"I can say with certainty that the flooding situation has changed almost in the blink of an eye," he said.

“They told us that there was no time to pack our bags and that we had to leave because the dam was maybe going to break,” Denise Audet said. She said everything happened so quickly she “didn’t have time to be scared.”

"I cannot tell you how long we will be in this state of emergency. If the flooding is severe there could be weeks of recovery operations."

Premier Doug Ford has also pledged the provincial government's support, and will visit the region on Friday.  

Canada capital declares flooding state of emergency

While levels on the Rideau River have stabilized, the Ottawa River is expected to rise about half a metre from Constance Bay to east of Cumberland by the weekend, according to South Nation Conservation.

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