Denzer. Her job: Keeping the dammed-up pool behind Lock and Dam 5 at a navigable nine feet for barges.
Shallow points showing up as river flow ebbs
MINNESOTA CITY, Minn. – The Army Corps is throttling down the flow of the Upper Mississippi River through its 18 dams to prevent shallows from developing and halting barge traffic. Lockmaster Judy Denzer at Lock and Dam 5 in Minnesota City calls it “a drought watch.” In a KTTC interview, Denver said the summer’s rain shortfall could drop navigation channels below the essential nine-foot depth. If barges go around, they’re stuck, she said. Last summer the Lower Mississippi, which has no dams, was jammed with grounded barges and tourist cruise boats. River commerce halted. In the Upper Mississippi, which s dammed, each dam has backed upa lake — “pools” in Corps parlance. The lakes, one after the other, prevent the river from drying up in extraordinarily dry seasons. This requires keeping gates on the dams lowered so the lakes maintain depths of at least nine feet. Even so, there are some “really shallow places” right now, said Elizabeth Nelson, the Army Corps water management supervisor. At this point, these shallows pose special danger for personal watercraft outside the main navigation channels, Nelson said.
Lock and Dam 5. Holds back a pool all the seven miles upstream Lock and Dam 4 at Alma.