By JIM SUHR and JIM SALTER
ST. LOUIS (AP) - Heavy rains swelling the Mississippi and Missouri rivers are causing headaches for barge operators.
Locks that are being closed along the Mississippi River could snarl barges headed from St. Louis to Minnesota, as well as southbound shippers trying to get to St. Louis and then to the Gulf of Mexico.
Some companies already have shrunk their barge sizes to make the vessels more maneuverable in the stronger currents.
Four locks have been closed between the Missouri towns of Canton and Clarksville. A fifth will close Saturday.
The flooding follows months of drought that were equally hard on shippers. The Mississippi River reached near-historic lows in January, forcing lighter loads on barges so they wouldn't scrape the bottom. Officials also blasted rock and dredged to keep parts of the river passable.
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