Navigation on the Upper Mississippi and Illinois rivers continues to improve as warmer temperatures have reduced ice accumulations, according to the U.S. Department of Agriculture.

The ice has restricted or halted barge traffic this winter, which has been the coldest since 1978-1979 for six Midwest states. During the last four weeks (March 9 to April 5), an average of 374 empty barges per week have transited upbound at Mississippi River Locks 27 (near St. Louis), according the USDA’s Grain Transportation Report (GTR) released today. This is a big jump compared to January through early March, when upbound empties averaged 137 barges per week.

For the week ending April 5, a total of 641 barges transited upbound at Locks 27 — 404 were empty and 76 contained fertilizers, according to the GTR.

On April 9, the USDA said the maximum ice thickness on Lake Pepin on the Mississippi River was 22 inches, well above the normal 12 to 15 inches of ice that a barge can break through for passage through the lake. Once the ice on Lake Pepin is thin enough for barges to navigate, this will permit the eventual opening of the entire navigable portion of the Mississippi River, the USDA said.