Drought has driven the Mississippi River to historic low levels, choking US agricultural exports.
The Mississippi River basin produces about 92% of US agricultural exports, including 60% of US grain exports, which travel down the river to the Gulf to ship across the world.
Coal is in high demand right now, Calhoun said, and the low water levels present a challenge to ship it out of the country.
He said higher food prices at the grocery store are just the first way consumers will start feeling the impact of low water levels.
A barge tow passes under the Mississippi River bridges in Vicksburg, Mississippi, on October 11, 2022.