After a harsh winter, the Lake Carriers' Association said that Great Lakes shipping lost 82 ship days due to icebreaking issues.
Related:Video shows scale model of Soo Locks testing ice flowThe ice season dragged on into April as Coast Guard icebreaking crews continued to work to free ships.
The president of the Lake Carriers' Association, Jim Weakley, said the problem requires America's attention.
According to data from the NOAA, the ice coverage on the Great Lakes spent much of mid-January through March above the historical average.