Lake Michigan and Lake Huron could hit record low water levels in the next six months. That’s according to a projection by the U.S. Army Corps of Engineers.
Lake Michigan and Lake Huron are functionally one body of water – they’re connected at the Straits of Mackinac. They’ve been below their long-term average for more than a decade.
John Allis is the Chief of the Great Lakes Hydraulics and Hydrology Office with the Army Corp’s Detroit District, and he talked with me about this for today's Environment Report.
"Really, it’s just a product of Mother Nature. More often than not we’re seeing drier months and lower supplies of water than we are seeing those wetter months. Anytime we seem to make a gain against the long term average, we see another stretch of dry weather that brings the water levels back down."
He says unfortunately, we don't have a clear picture of how climate change might affect water levels.
"And that’s not for a lack of effort from a lot of scientists. There was recently an International Upper Great Lakes Study – that was a study commissioned by the International Joint Commission, and they spent a lot of effort looking at different climate change scenarios and seeing how that would impact water levels in the Great Lakes. A lot of what they concluded was that it was still difficult to tell which way it could go. I think previous studies suggested a higher chance of lower water levels in the Great Lakes, but their information seemed to suggest that it’s really up in the air."
There’s also been some controversy around dredging by the Army Corps in the St. Clair River in the 1960s. Allis acknowledged that those dredging projects and previous projects on the St. Clair River affected the water levels in the Michigan-Huron system.
"They caused a permanent 10-16 inch drop on Michigan-Huron, and that’s always going to be there since the 1960s. But it’s important to point out that since the 1960s, Michigan-Huron have both set record highs as well. So, it’s not something that’s going to guarantee levels are always going to be low on Michigan-Huron."
He says these extremely low water levels have been tough on recreational boaters and commercial shippers.
"Especially for commercial shipping, that they have to light load their boats, they can’t carry as much in a load. Rec boaters we hear a lot from them as they’re having trouble getting in and out of some of the different harbors and marinas on the Great Lakes. Certainly it has impacted a lot of stakeholder groups, having water levels this low."