By GRANT SCHULTE and JOSH FUNK
OMAHA, Neb. (AP) -- Nebraska and Iowa residents are already dealing with some flooding along the Missouri River, and officials say conditions will worsen in the weeks ahead when the deluge of water flowing downstream surpasses record levels.
The U.S. Army Corps of Engineers predicts the Missouri River will reach levels 5 to 7 feet above flood stage at most locations in Iowa and Nebraska by mid-June, and some areas could remain inundated with water for several months once they are flooded.
The river levels will increase because the Corps is planning to increase the amount of water released from Lewis and Clark Lake significantly in the weeks ahead to deal with snowmelt and heavy spring rains.
Some Nebraska and Iowa homeowners who live in low-lying areas near the Missouri River have already evacuated to avoid floodwaters, but the flooding so far has mostly affected several thousand acres of farmland in the two states.
The northeast Nebraska towns of Niobrara and Santee are dealing with flood water from Lewis and Clark Lake, and cities all along the Missouri are bracing for record floods over the next month.
Nebraska officials are concerned that water from the lake could cut off highway access to Niobrara if the Corps isn't able to reduce the level of the lake, and Gov. Dave Heineman visited the town of about 370 Tuesday as part of a flooding tour.
Rozann Graves, who owns the Niobrara Trading Post, said residents are worried about the flooding, expecting the worst but not knowing how bad it will actually get.
"It's not going to be a good year for anyone around here," Graves said.
Many Niobrara businesses depend on tourism. Local officials predicted that 75 to 80 cabins along the Missouri River were flooded or about to be. Flooding also was expected at the local golf course.
"We're scared to death we're going to lose our economic well-being," said John Moore, chairman of the town's board of trustees. "That's our economic development driver here -- tourism."
Niobrara residents have already built sandbag walls around sewage processing plants to help prevent backups, and one of the main highways into town from the west was reduced to one lane.
The water also could threaten local schools, Niobrara Superintendent Margaret Sandoz said.
About 100 miles east of Niobrara, Sioux City, Iowa, officials are making plans to protect riverfront businesses from the predicted floodwaters that will arrive next month. The Terra Industries fertilizer plant is a particular concern because of the substances used in making fertilizer that could contaminate the river.
Sioux City fire spokesman Joe Rodriguez said volunteers were being recruited to help fill 15,000 sandbags Tuesday evening. "We have some businesses along the river we're worried about," Rodriguez said.
The Sioux City area will be one of the first places affected when the amount of water being released from the Gavins Point Dam increases. The Corps plans to double its current rate of releasing about 75,000 cubic feet of water per second from the dam by mid-June.
Rodriguez said it's hard to predict exactly where the flood water will go ahead of time because the river has never been this high before. So officials are working to prepare as best they can based on projections.
Across the river in South Sioux City, Neb., officials are planning to build a 7,000-foot-long concrete wall on top of an existing levy to protect the core of the town, and they hope to complete it by June 15 before the river hits peak levels.
City Administrator Lance Hedquist said he hopes the new concrete wall will be able to protect the core of South Sioux City, including Wayne State College's new northeast satellite campus.
Iowa officials are making plans to respond to flooding, but no counties had declared an emergency as of Tuesday and no mandatory evacuations had been ordered, said Iowa Homeland Security spokeswoman Stephanie Bond.
Most of Iowa's flooding so far has affected farm fields and a few low-lying areas near cities such as Sloan, Council Bluffs and Hamburg. An RV park in southwest Iowa along the border of Fremont and Mills County closed as a precautionary measure.
People who live close to the river in Fort Calhoun, Neb., Council Bluffs, Iowa, and Hamburg, Iowa, have evacuated because the water was already nearing their homes.
Fort Calhoun resident Bill Soll and his wife spent Memorial Day weekend moving because of floodwaters that were about 10 feet away from their home Tuesday morning. Soll said it looks like this year's flooding will surpass the 1993 flooding and maybe even the record 1952 floods.
"In 1993, (the water) was like this, but they weren't saying it would get worse," Soll said. "This time I think it's going to keep coming."
During the 1952 flood, the Missouri River crested at 30.24 feet at Omaha, and that was 5 feet higher than ever before. Flooding in the Missouri River Basin caused $179 million in damage.
This summer, the Corps of Engineers predicts the river will crest somewhere between 34 feet and 36 feet at Omaha.
Nebraska officials are in the process of building a list of National Guard resources that can be used to battle flooding if needed.
Copyright 2011 The Associated Press.