Lake Pepin Ice Survey Helps Predict Spring Shipping
MINNEAPOLIS (WCCO) -- When your mission is to measure ice on an unpredictable river, you need a good rig.
Bill Chelmowski and his 2018 Diamondback Corvette turbo-powered air boat are out to cruise 15 miles on the ice-covered Lake Pepin.
"The thickest ice I can remember is 34 to 36 inches," Chelmowski said.
Every spring the Army Corp of Engineers, St. Paul District survey team collects ice measurements up and down Lake Pepin. The goal is to see what winter has brought and when spring might begin.
"What we do is go out and drill holes to measure ice. This gives a good measurement for the towing companies to understand when the ice is thick enough to either break through, or we lose the ice so they can come through," Chelmowski said.
Those measurements help barge companies determine how soon the shipping season can begin.
"They can go through 10 to 12 inches of ice, what they call breaking through the ice," Chelmowski said.
Clearly, we're not there yet. Out on the frozen lake the auger fires up and the thickness gauge goes down.
Chelmowski's assistant yells out, "two inches of white for a total of 18."
That's about half the ice depth of the Mississippi's most severe winters. In fact, Chelmowski's air boat is finding open water in areas normally sealed in ice.
This year we're averaging about 17 inches at the thickest," Chelmowski said.
On average, shipping season starts around the third week of March. Predictions made in part by our own, Punxsutawney Bill.
"That's up to mother nature," Chelmowski said.
To follow ice thickness data the U.S. Army Corp of Engineers St. Paul district posts the information on its website.