This week’s forecast for slightly warmer weather has officials on high alert for potential ice jams and flooding along the Missouri River in Iowa, Nebraska and Missouri. Due to the extreme cold the last several weeks, much of the waterway is frozen up-river, all the way to within a few miles of Gavins Point Dam, near Yankton, South Dakota. Paul Johnston, spokesman for the U.S. Army Corps of Engineers in Omaha, says ice cover is much more prevalent this year.
“Most of the ice in the Bismarck, North Dakota, area and the rest of the river, from about Sioux City and Omaha all the way down to Jefferson City, Missouri, is 50 to 75% covered with floating ice,” Johnston says. “It’s been a pretty tough time.” He says the ice cover has not caused any problems on the Missouri River, not yet, at least.
“When the river freezes, the water will move very efficiently under the ice,” Johnston says. “It’s the transition times when you’re either forming ice or the ice is breaking up that can be an issue. We’re going to have to keep a very sharp eye over conditions over the latter part of this week.”
Temperatures across much of the region are expected to top out in the 30s and 40s, the warmest it’s been in some areas since early December. Johnston says there’s growing concern about possible spring flooding on the river as they’re monitoring the snow pack conditions across the region.
“The mountain snowpack is running about 85% of normal for this time of the year but the snowpack on the plains, obviously, is well above normal for this time of the year,” Johnston says. “We are paying close attention to that and have already opened conversations with some of the state emergency management folks.” The snowpack in parts of northwest Iowa is still as deep as 36 inches. He notes, reservoirs on the Missouri River are at or above their normal levels for this time of year.
By Jerry Oster, WNAX, Yankton