IOWA CITY, Iowa (AP) — The University of Iowa and cities along the Iowa River prepared for the worst Thursday amid concern that rising waters could top a key reservoir and inundate the area next week.
A projection released Thursday showed that Coralville Lake, a reservoir built to control flooding on the river, would crest next week less than one foot below the emergency spillway. Authorities said they can manage flooding as long as water doesn’t top the spillway.
But emergency managers cautioned that rainfall in the Iowa River basin in the coming days could change the forecast for the worst and cause waters to top the spillway, which was breached during the devastating floods of 2008 and 1993. They said that no rain was expected until at least Saturday evening, but after that the forecast of possible storms was concerning.
Heavy recent rains in the upper Midwest have caused the Mississippi and many of its tributaries to rise sharply, causing significant flooding in Iowa, Illinois and in Missouri north of the confluence with the Missouri River near St. Louis. The Mississippi remains below flood stage from St. Louis to the south.
A Mississippi River lock and dam was set to be shut, the U.S. Army Corps of Engineers said Thursday, as it tries to protect the town of Clarksville, Missouri, where the river is already 6 feet above flood stage and rising.
The popular National Tom Sawyer Days festival in Hannibal, Missouri, will go on as planned over the Fourth of July weekend, although parts of a highway south of town are expected to be closed because of flooding.
The Corps of Engineers has activated its Emergency Operations Center in St. Louis, a move that enables the agency to provide personnel and resources to support flood-fighting efforts.
The federal agency, which manages Coralville Lake in Iowa, said Thursday that it is opening the gates to increase the outflow of water to 18,000 cubic feet per second, near its maximum.