Missouri River

A bicyclist rides along the rising Missouri River in Omaha near the Bob Kerrey Pedestrian Bridge on Thursday.

Record rains in the upper Missouri River watershed have prompted the National Weather Service to extend its flood warning for most of the river between Iowa and Nebraska.

How bad the flooding will be is unclear, given that many levees remain broken, weakened or not yet fully repaired.

But Interstate 29 could flood shut north of Crescent, Iowa, as early as Monday, based on forecasts by the weather service. In the Omaha-Council Bluffs metro area, riverside parks like N.P. Dodge, Tom Hanafan and Fontenelle could again take on water. In the Plattsmouth, Nebraska, area, water could flow into areas where levees are breached.

In Iowa, officials warned residents in southwest Mills County who live west of I-29 and and south of Lambert Avenue to stay alert and be prepared to evacuate if water starts to rise. 

Bryon Miller, a weather service meteorologist, said that estimating the impact of high river levels — even on critical infrastructure like I-29 — is tougher than it used to be.

“Definitely, (the river) is going to cause flooding; there’s a high probability of that,” Miller said Sunday. “The extent of the flooding is not as clear.”

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Some areas that traditionally don’t flood could flood because of broken levees, he said. But if the river spreads into various pockets of the valley, that could lessen its crest downstream.

“I don’t think there will be any big surprises; we’re not expecting anything as bad as occurred in March. That’s important for people to know.”

Two to six times the normal rainfall has fallen over the Missouri River basin in the first two weeks of September. That has pushed some tributaries into major flood stage, feeding the rise in the Missouri River. In response, the U.S. Army Corps of Engineers is reducing discharges from its lowermost dam on the Missouri. Releases from Gavins Point dropped to 60,000 cubic feet per second over the weekend, down from 70,000 cfs.

“We are reducing releases … to reduce the chances of floodwater reaching Interstate 29 north of Omaha,” said John Remus of the corps.

The reprieve won’t last long. By Thursday, the corps plans to step up releases and by the end of the week take them higher than they’ve been all summer — to 80,000 cfs.

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