LAKE CITY, Minn. – Bill Chelmowski eased the airboat from Lake Pepin's open waters onto a pockmarked sheet of ice, already certain of what he'd find beneath the surface.
In this crucial stretch of river, the roar of an airboat is the cadence of spring. Each year, the U.S. Army Corps of Engineers measures Pepin's ice thickness to help divine when the first tows can break through and reach St. Paul, opening the navigation season.
Chelmowski's auger jabbed through the slushy sheet like a rotten tooth Thursday, a sign that the sleeping titan of commerce called the Mississippi is ready for business — at least along the tract often slowest to melt.
Now if only the towboats could get there.
High water and flooding downstream have closed locks dotting the river from Iowa into Missouri, halting commercial traffic and setting up what could be the latest start to the shipping season on record.
The first tow normally punches through Pepin's ice in the third of week March. But some in the towing industry worry the later melt and flooding could mean two or three more weeks before barges arrive in the Twin Cities.
Blame it on the wet fall, the deep freeze that followed and this year's record-breaking late snow.
"It's a recipe for a mess," said Lee Nelson, president of Upper River Services in St. Paul, which moves and maintains barges in the Twin Cities.