Water levels in Lake Michigan and Lake Huron are expected to set a record low this year, dry conditions are accelerating a long-term trend and commercial shipping and recreational boaters are facing issues.
The problem is a long-term cycle of too little water from melting snow and rain to counter the effects of evaporation on the lakes, Keith Kompoltowicz, chief of watershed hydrology for the Army Corps of Engineers in Detroit, told CNN.
Last winter, too little snow fell in the Great Lakes region to fully replenish the lakes. Lake Michigan and Lake Huron typically rise a foot after the spring melt, but the lakes only rose 4 inches last spring, Kompoltowicz said.
Add that tiny rise to a very hot, very dry summer that sucked water out of the lake like a straw and you have a recipe for the decline in lake levels that is under way today, he said.
There's too little data to say the problem is attributable to global warming, he said. It's also a cycle that has been seen before.
"In years past, there was always a buffer," said Chris Berkey, a commercial skipper who delivers staples such as cement to industries in harbors that dot the coastlines. "That buffer's gone."
In Frankfort, Mich., a popular salmon run on the Betsie River attracts tourists drawn by the lure of fishing a rare, naturally replenished population of the prized fish, city manager Josh Mills said.
"We see people from Texas, from Georgia, from Ohio, Illinois, other areas of Michigan," he said.
But low lake levels last year dried up the run, leaving salmon flopping in the mud and forcing the state Department of Natural Resources to close the run to protect the population.