Minor flooding conditions on the Upper Mississippi, Arkansas, and Tennessee Rivers have reached levels that could impact barge shipping, the United States Department of Agriculture announced Thursday.

On December 16, the Mississippi River at St. Louis rose above 25’, a threshold where the Coast Guard restricts tows of barges greater than 600’ to daylight-only transit in the St. Louis Harbor and requires tow boats to have minimum horsepower requirements.

In spite of the recent restrictions, the USDA noted that year-to-date barge shipments have amounted to 33.2 million tons, about the same as last year, but 15% higher than the 5-year average.

Barge rates continue to decline as barge demand has been weak. St. Louis export barge rates have dropped from 535% of tariff ($21.35 per ton) in late September to 190% of tariff ($7.58 per ton) on December 15.