Water levels in rivers and lakes of the central and southern Northwest Territories are at — or near — record lows this year after an extremely hot and dry stretch lasting months.
"It's been steadily decreasing all summer and, as a result, the Mackenzie River downstream is also extremely low and record low at different locations," said Ryan Connon, a hydrologist with the Government of the Northwest Territories.
"There's a huge moisture deficit that needs to be filled before water levels can return to normal. So what that means is, essentially, if we have average snowpack and average rainfall next year, that won't be enough water to bring water levels back to average."
He says the levels are low this year, but his attention is also on how wildly water levels are swinging from year to year.
Connon said Great Slave Lake serves as a perfect example. Water levels in 2020 and 2021 reached near record highs, but this year they're at a record low.
Wild fluctuations also seen
"This level of fluctuation and variation is something that we haven't really seen over the almost 90-year record for Great Slave Lake," said Connon.
Connon says the wild fluctuation in water levels is a reflection of weather extremes from drought to precipitation. It has the ability to affect communities in multiple ways, including water needed to fight wildfires.
The low water this year also means that hydro plants in the southern N.W.T. were producing less electricity for Yellowknife and its surrounding area, and diesel generators were needed to help to meet the need.
Shipping was also affected, with low water on the Mackenzie River forcing some goods destined north on a 4,000-kilometre detour.
Human-caused climate change from the burning of fossil fuels makes extreme weather more frequent, and intense — including excessive heat, and longer and more frequent droughts.
"There's some unknowns for the future. Looking at the shifting climate, there's a lot of conditions ... we haven't seen before," Connon said, adding they are looking at the complex interactions it has with the land, such as permafrost.
"There is a threshold as to how low a river can go up to the point where groundwater is completely sustaining it. And we're reaching that minimum threshold on some of the rivers. So they probably won't dry up too much more, but we're hoping that we won't see those conditions and we're hoping for some more rain coming in through 2024."