N.W.T. communities prepare for spring floods, as high water levels persist

During the summer and fall months of 2020, the Great Slave Lake reached the highest water levels in its recorded history. Communities that are prone to flooding are preparing for an abnormal spring ahead.

Communities along the South Slave are preparing for flood risk after record high water levels.

Great Slave Lake reached the highest water levels in its recorded history during the summer and fall of 2020, according to the government of Northwest Territories. (Hannah Paulson/CBC News)

After a summer of unprecedented water levels, communities on Great Slave Lake and along the Dehcho (Mackenzie River) in the Northwest Territories are preparing for another spring of potential flooding.

Last summer and fall, Great Slave Lake reached the highest water levels in its recorded history. The lake feeds the Dehcho and most of the territory's communities sit on its riverbank. 

On Tuesday, the government issued a warning to property and cabin owners to get ready now, before the spring floods begin. The communities most prone to flooding in the south are Hay River, Fort Simpson, Fort Liard, and Nahanni Butte.

A look at water levels in Fort Simpson during the 2020 spring breakup season. Water levels on the Mackenzie River stopped just short of declaring a local state of emergency. (Submitted by Josanne Kenny)

Researchers with the N.W.T., the federal government, and the University of Saskatchewan say the extra water in Great Slave Lake is coming from the rivers that feed into it. They don't expect to see water levels return to normal any time soon. 

"We have not experienced water levels at this level, certainly at this time of year, to this degree in the past. So, you know, in terms of impacts, it's really hard to predict," said John MacDonald, a top environment official with the territorial government.

"What we do know, though, is that with this much precipitation in the watershed, it's likely that flooding will occur. So what we're hoping to do is to get the word out early and often." 

Community leaders worried about flood risk, but preparing

Fort Simpson Mayor Sean Whelly said he's already worried about flood risk this year after flood waters last year nearly forced community leaders to declare a state of emergency. They almost had to evacuate half a dozen households.

Now, a meeting is happening next week to plan for this spring. 

"We don't want to have to scramble at the last minute," Whelly said. 

A photo from the NWT Archives showing the 1963 flood which submerged most of the island under water. The area shown is the modern-day papal grounds site, also known as the flats. (NWT Archives/Sacred Heart Parish (Fort Simpson) )

As Fort Simpson prepares for a potential emergency, Whelly questions who is ultimately responsible for flood preparation since the territorial government will only cover the cost once an emergency is declared, even though flood concerns recur yearly, Whelly said. 

In 1963, Fort Simpson had a major flood that submerged most of the island in water. Many residents were airlifted out of the community. Only a few spots in town remained untouched. 

Erosion from flooding is an ongoing concern 

Last May, hundreds of residents living on Vale Island and West Channel in Hay River, N.W.T., were evacuated due to flood risk. The south shore of Hay River is listed as one of the most prone to hazardous flooding due to ice jams at the edge of the Great Slave Lake. 

Ice fills the Hay River on Tuesday, May 5. The buildup of ice led the town to issue an evacuation order for the flood-prone areas of Vale Island and West Channel Monday evening. (Anna Desmarais/CBC)

K'atl'odeeche First Nation neighbours the area. Chief April Martel said they're collaborating with other departments and working with guardians who monitor the water levels to ensure that they're prepared for when the ice begins to break. 

In prior years, April Martel said that the damage to property hasn't been of too much concern, but they're making sure that they are prepared this year in case things change. 

Martel is concerned about how the high water levels will intensify coastal erosion, causing "huge damages." 

"The bank is eroding really fast every year with flooding," Martel said. "It's really scary."