It will likely come as no surprise to residents along Yellowknife Bay watching their shoreline extending further and further out into the bay that Great Slave Lake is once again breaking records for the lowest water levels ever recorded.
Water levels on the lake are now at their lowest point since Yellowknife's founding in 1934, smashing the previous record set in mid-July of last year by 20 cm.
“Low water levels on Great Slave Lake have impacted access to traditional fishing, hunting, and trapping areas, barge access to communities, boat launches, and reliable navigation on the lake and connected rivers,” said Thomas Bentham, a spokesperson for the GNWT Department of Environment and Climate Change.
He added that very low water levels can trigger higher water temperatures and impact lake productivity, causing changes in water quality conditions. For example, less water means less dilution of substances, such as salts and metals, which can influence the health of fish and other aquatic life. Low water levels can also decrease or change available habitat of fish, waterfowl, and fur bearers, such as mink and muskrat. Aquatic weed beds that provide food and cover for other organisms can dry up, and shoreline vegetation will struggle to survive.
The data was collected from the Water Survey of Canada, which operates more than 100 hydrometric stations across the territory, collecting real-time water levels. Monitoring is ongoing and will continue throughout this low-water period.
“These results will be compared with past data to enable scientists to assess the aquatic quality of Great Slave Lake,” he said.
When asked about what could be done as the territory is heading into another wildfire season, Bentham said low water levels will not affect the territory's ability to protect communities and other assets, since there is still more than enough water to draw from area lakes.
“We also do not depend on water as the single source of fire suppression. We use a wide variety of fire suppression tools,” he said.
Bentham added that the main cause of wildfires in the territory are humans and lightning.