DECATUR, Neb. — Odd thing about the Missouri River bridge here.
When it was built in the early 1950s, there wasn't a river under it, just a dry riverbed.
The Missouri looped farther east. It didn't flow under the bridge until the U.S. Army Corps of Engineers relocated the river there after the Korean War.
But now the Missouri River is challenging that engineering, and this toll bridge connecting Decatur to Onawa, Iowa, is one of the most threatened crossings in the Midlands.
As the flooding Missouri River overflows its banks it is pushing eastward into Iowa, searching for its old channel. That channel now is an oxbow lake called Blue Lake.
In the river's path is Iowa Highway 175. The roadbed is acting as a dam, forcing floodwaters back toward the river's current channel. All that flowing water is eating away at the riverbank under the bridge's Iowa end.
If the river wins this battle, the road to the bridge could collapse.
So far the Missouri has eaten away more than 15 feet of land beneath the bridge on the Iowa side.
So powerful was the flow initially, the river even shoved downstream some of the 400 tons of rock that crews dumped under the bridge in hopes of protecting the embankment.
"It's amazing to see the water flow under there. It was so powerful," said Bob Younie, director of maintenance for the Iowa Department of Transportation.
Fearing the riverbank might collapse, the state of Iowa shifted its flood-fighting efforts about 250 feet east. It is spending $1.3 million on 25,000 tons of rock that are being piled along Highway 175 as it approaches the bridge.
The idea — which appears to be working — is to push the water back toward the main river channel.
Pat Gubbels, whose Norfolk, Neb., firm, Theisen Construction, maintains the bridge for the Burt County Bridge Commission, said Iowa's work appears to be slowing damage to the abutment, the point where the road meets the bridge.
Officials on both sides of the border say they believe the bridge crossing will survive.
Mark Traynowicz, state bridge inspector for Nebraska, said he believes the bridge — which has concrete piers and pilings extending down about 100 feet to bedrock — will withstand the force of the river.
"We plan for that. These bridges are designed for that," he said.
About 600 people live in the historic community of Decatur, and many depend on the Iowa town of Onawa for jobs, doctor care and shopping. Likewise, Iowa residents travel to Nebraska for jobs, dining and other pursuits.
About 2,000 vehicles travel the bridge daily.
"It's very important to our community," said Therese Magill, village clerk at Decatur, the second-oldest settlement in Nebraska. "The night they closed it, it was eerie. It was the weirdest thing I've ever felt in my whole life, it was so quiet."
Too quiet for this town to survive economically.
"This bridge needs to be open — our town is really suffering," said Tom Farrens, co-owner of the local Green Lantern steakhouse. Business is down significantly in town since the bridge closed on June 27, Farrens said.
"There's a big fear the bridge won't reopen," he said. "Enormous."
Clark Beck, a member of the Burt County Bridge Commission, said he understands how some people might object to solutions that require re-engineering the river's course.
"We have to protect the environment. I don't have any argument with that at all. But you have to use some common sense. We still have a lot of people who have to be considered in that same equation," he said.
John Remus, chief of the hydrologic engineering branch of the Omaha District of the Army Corps of Engineers, said he doubts the river will be able to abandon its current channel and successfully move to the old channel farther east.
The Missouri has been moving at a powerful clip under the bridge, he said. It was clocked Tuesday at 14 feet per second, about three times its normal speed. That translates to about 9.5 miles per hour.
"There will be damage, but it should go back to its alignment," he said.
Magee said people in the Decatur-Onawa area are well aware of the river's nature.
"Before the river was channeled, it was a wild river, it went where it wanted to," she said. "And that's what it's trying to do now."
Contact the writer: 402-444-1102, nancy.gaarder@owh.com
Click here to view a PHOTO SHOWCASE of the floods as seen by plane
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