The end of 2015 saw the north arm of the Great Salt Lake dip down to its lowest recorded level. UPR’s Jennifer Pemberton tells us that depending on what happens this winter, the rest of the lake might get down there too.
The Great Salt Lake is a terminal lake meaning it has no outlet. And as such it’s a reflection of everything that happens in its watershed, which includes the major rivers of Northern Utah as well as all the communities of the Wasatch Front. So, it was a big deal when the team at the US Geological Survey noticed in late 2015 that there was the lowest amount of water in the north arm of the lake they had ever seen.
“We’ve been watching it. We knew that the north arm was on its way down,” says USGS hydrologist Cory Angeroth. His team is in charge of monitoring lake and river levels across the state. The USGS has been operating lake gauges on the Great Salt Lake since 1875.
The Great Salt Lake is essentially two bodies of water right now separated by the Union Pacific railroad tracks that span the lake on a raised causeway. The big rivers that feed the lake -- the Bear, the Weber and the Jordan -- all flow into the lake to the south of that causeway.
“It always had a pathway to flow from the south arm into the north arm,” says Angeroth. “Now that the culverts in the causeway are closed, the causeway is acting like a dam.”
The water in the larger south arm of the lake is about two feet higher right now, which sounds nice, but it’s hovering within a foot of its historic low. There are plans to punch a new hole through the causeway this year to allow water to flow back and forth again, but depending on when that happens, it could mean that the whole lake drops down below the record set in 1963.
“If we get above average snow pack, that would be great for the lake,” says Angeroth. “If we get below average snow pack there is the potential that we could be seeing a record low.”