State transportation officials Monday afternoon said they are monitoring the rising waters of Coralville Lake but don’t now expect the need to close Interstate 380 as they did for two weeks during flooding in 1993.
Cathy Cutler, transportation planner with the Iowa Department of Transportation in Cedar Rapids, noted Monday afternoon that Coralville Lake in July 1993 reached an elevation of 716.7, or two feet above its current projected crest of 714.7 feet expected on June 17.
Cutler noted water begins to lap on to the beams of northern abutments of the twin bridges on Interstate 380 when the lake water reaches 714 feet.
However, Bruce Brakke, the DOT’s bridge maintenance engineer in Ames, on Monday said the agency learned from the 1993 flood that it did not have to be “that concerned” when some of the bridges’ girders go under the water.
Brakke, who was among those who inspected the Interstate 380 bridges in the 1993 flood, said the lake water at that spot is “slow-moving” and that the Highway 965 bridge and a railroad bridge upstream help to screen out debris.
In 1993, the water was higher and covered more of underside of the Interstate 380 bridges, he added.