LAKE CITY, Minn. (AP) — The ice on a southeast Minnesota lake is thinning, but not by much.

KAGE-AM in Winona reports the ice on Lake Pepin is still 21 inches thick in four spots, a mere 2 inches thinner than when it was measured two weeks ago.

In other parts of the lake, ice depths ranged from 19 inches to just 2 inches at the north end.

The U.S. Army Corps of Engineers is taking the measurements to predict when the first towboats of the year can make it to St. Paul, marking the kickoff of the shipping season. In the past 10 years, the average opening has been March 20. But this year, no towboats will be able to get through before March 28 due to a lock and dam construction project in Red Wing.

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