National Guard troops worked with local residents to stem the damage from the widespread flooding in Iowa that killed at least three people, forced tens of thousands to evacuate and severely damaged the state's corn crop.
The drenching has also severely damaged the corn crop in Iowa, America's No. 1 corn state, and other parts of the Midwest at a time when corn prices are soaring and food shortages have led to violence in some poor countries.
Iowa has lost 2 million acres (810,000 hectares) of soybeans and 1.3 million acres (530,000 hectares) of corn. Sixteen percent of the state's 25 million acres (10.12 million hectares) of tillable farmland is under water.
In addition to the three killed in the flooding and storms that caused it, 12 others died in recent tornadoes.
The swollen Iowa River, which bisects Iowa City, was topping out at about 31.5 feet (9.6 meters) — a foot and a half (46 centimeters) below earlier predictions. But it still posed a lingering threat, and was not expected to begin receding until Monday night.
A week's work of frantic sandbagging by students, professors and the National Guard couldn't spare this bucolic college town from the surging Iowa River, which has swamped more than a dozen campus buildings and forced the evacuation Sunday of hundreds of nearby homes.
The university said 16 buildings had been flooded, including one designed by acclaimed architect Frank O. Gehry, and said others were at risk.
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Iowa City Mayor Regenia Bailey said 500 to 600 homes in this city of about 60,000 were ordered to evacuate and hundreds of others were under a voluntary evacuation order through the morning.
Gov. Chet Culver said it was "a little bit of good news" that the river had crested, but cautioned that the situation was still precarious.
"Just because a river crests does not mean it's not a serious situation," he said. "You're still talking about a very, very dangerous public safety threat."
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Elsewhere, state officials girded for serious flooding threats in Burlington and southeast Iowa including Fort Madison and Keokuk. Officials said 500 National Guard troops had already been sent to Burlington, a Mississippi River town of about 27,000, and some people were being evacuated.
In Cedar Rapids — where flooding had forced the evacuation of about 24,000 people from their homes — residents waited hours to get their first up-close look since flooding hammered most of the city earlier this week.
Some grew angry after long waits to pass through checkpoints. Cedar Rapids officials also were inspecting homes for possible electrical and structural hazards.
"It's stupid," said Vince Fiala, who said he waited for hours before police allowed him to walk five blocks to his house. "People are down on their knees and they're kicking them in the teeth."
The city's municipal water system was back to 50 percent of capacity Sunday, a big victory after three of the city's four drinking water collection wells were contaminated by murky, petroleum-laden floodwater. That contamination had left only about 15 million gallons (56.78 million liters) a day for the city of more than 120,000 and the suburbs that depend on its water system.
Elsewhere in the Midwest, hundreds of members of the Illinois National Guard headed to communities along the swollen Mississippi River on Sunday for sandbagging duty while emergency management officials eyed rain-swollen rivers across the state.
Two levees broke Saturday near the Mississippi River town of Keithsburg, Illinois, flooding the town of 700 residents about 35 miles (56 kilometers) southwest of Moline. The National Weather Service said the Mississippi would crest Tuesday morning near Keithsburg at 25.1 feet (7.65 meters). Flood stage in the area is 14 feet (4.27 meters). Rising water threatening approaches also prompted Illinois officials to close a Mississippi River bridge at Quincy.