CEDAR FALLS, Iowa (AP) -- Residents were ordered to evacuate low-lying sections of towns along the overflowing Cedar River on Wednesday, and communities along the Mississippi River were warned that new rainfall would boost their expected flood crests.
Officials in Wisconsin, where this month's rainfall is approaching a record, planned to drain water from one reservoir to ease pressure on a dam, and were monitoring dams elsewhere in the state. High water in Indiana burst a levee Wednesday and flooded a vast stretch of farmland.
More rain spread across parts of Iowa on Wednesday, including some flood-threatened areas. The showers came as a band of storms rippled across the northern Plains.
A sandbagged levee prevented the Cedar River from flooding this northeastern Iowa city, but officials asked for extra volunteers to help shore it up. Just downstream along the Cedar River, the neighboring city of Waterloo ordered a mandatory evacuation of some neighborhoods because the ground was saturated and pumping stations couldn't keep up, officials said.
"This is not a recommendation, this is not an encouragement, this is a mandatory evacuation," Waterloo mayor Tim Hurley said at a news conference. "We need you out of there."
Hurley said the order affected about 60 homes and half as many businesses. He said volunteers also were being pulled out of the area. National Guard soldiers had blocked off bridges in and out of the downtown.
To the southeast in Cedar Rapids, more than 200 residents of a neighborhood near the river were told to seek higher ground.
In Vinton, electricity was cut Wednesday morning when rising water affected the city's municipal power plant, said Steve Meyer, the assistant emergency operations center manager. He said a 15-block area near the river had already been evacuated.
"The water is at least three feet deep. It's still coming up," he said of the town, home of about 5,000 people between Cedar Falls and Cedar Rapids.
The Cedar River had been expected to top the Cedar Falls levee during the night and deluge the downtown area of the city of 35,000 people some 88 miles northeast of Des Moines. But city spokeswoman Susan Staudt said early Wednesday that the sandbags had held.
The river peaked in Cedar Falls at about 14 feet over flood stage early Wednesday and had fallen nearly 2 feet by noon, authorities reported.
Thousands of volunteers who showed up Tuesday to help with the sandbagging effort "saved this city, but we are still at a critical point," Staudt said.
She said more volunteers were needed to help reinforce the sandbag wall, which rises several feet above the levee. Volunteers patrolling the sandbag wall during the night reinforced spots where water was seeping through, she said.
Along the Mississippi River, the National Weather Service has predicted crests of 10 feet above flood stage and higher over the next two weeks in the Missouri and Illinois stretch of the river. Most of the towns are protected by levees, but outlying areas could be flooded.
The river was 1.5 feet above flood stage Wednesday at St. Louis, on its way to 5.6 feet above, and the floating President Casino closed for the second time this year because of flooding on its riverfront access road.
With more rain falling upriver Wednesday in parts of Iowa, crests at Missouri's Mississippi River towns could be higher than currently forecast, said weather service hydrologist Jim Cramper.
"It's when the rain falls upstream that it's a bigger impact on you," Cramper said. "As this new batch of water comes down, the river could start creeping up again."
That reflects conditions that have existed all spring, said Susie Stoner, spokesman for Missouri's State Emergency Management Agency.
"We have rivers that have been at flood stage since March," Stoner said.
In Wisconsin, state and local officials monitored dams threatened by the high water from days of storms.
Wisconsin officials planned to let water out of the reservoir behind Primmer Dam, in the southwestern part of the state, to ease pressure on the weakening structure, said Russell Rasmussen of the Department of Natural Resources. He said a number of homes and a highway are located downstream from the dam.
"There's some seepage coming out," Rasmussen said. "We're concerned the dam is weakened to the point of becoming a problem."
As of Wednesday morning, Milwaukee had measured 9.21 inches of rain already this month - including a record 7.18 inches in a 48-hour period - and the June record is only 10.03 inches, set in 1917.
Officials in flood-damaged southern and western Wisconsin were worried about crop losses. One southwestern county reported losing $5.5 million in soybeans, hay and corn.
A levee failed early Wednesday in southwest Indiana near the town of Capehart, flooding several square miles of farmland near the White River, and Daviess County authorities urged residents to evacuate.
"We've got about a 40-yard swath of levee that's gone," said Indiana state Rep. Dave Crooks, speaking for the county's Emergency Management Agency. "We've got rapidly rising water in that whole bottom area."
Authorities also ordered as many as 300 residents north of nearby Maysville to evacuate late Tuesday after water topped a levee.