The federal government said Wednesday that 20 to 30 more levees may overflow along the Mississippi River from Burlington, Iowa, down to St. Louis.
Twenty levees have already overflowed this week, the Army Corps of Engineers said. The other levees could overflow if sandbagging efforts fail to raise the levees' levels.
The levees in danger protect rural, industrial and agricultural areas, not heavily populated towns. The levees protecting large towns are not as at risk of overflowing, officials said.
Record-breaking storms and flooding across six states this month are still forcing thousands of people to evacuate.
Since June 6, there have been 24 deaths and 148 injuries because of the storms and flooding, according to federal briefing documents obtained by The Associated Press.
Levees in west-central Illinois were breached early Wednesday as the swollen Mississippi River spilled floodwaters into Hancock and Adams counties, according to a CNN report.
"It's kind of a sad day," said Sheriff John Jefferson of Hancock County. "People put in a lot of manpower (to build up the levees) and all was lost."
The floodwaters will cover thousands of acres of farmland along about a 25-mile stretch from Warsaw to Quincy. Jefferson said all residents have left the area.
One breach forced the evacuation of the western Illinois town of Meyer.
Adams County Emergency Management Agency spokeswoman Julie Shepard said water breached the levee Wednesday morning and was starting to rise. It's mainly threatening farmland.
Shepard said the town has already been evacuated and authorities were patrolling Wednesday to make sure nobody is left behind. Only about 40 to 50 people live in Meyer.
A second breach happened farther south.
Floodwater Rescues
On Tuesday, the rising Mississippi River broke through another levee, forcing authorities to rescue about a half-dozen people by helicopter, boat and four-wheeler as floodwaters moved south into Illinois and Missouri.
But even as the water jeopardized scores of additional homes and businesses, officials said the damage could have been worse if the federal government had not taken steps to clear flood-prone land after historic floods in 1993.
The flooding Tuesday stopped car travel over two bridges linking Illinois and Iowa and threatened to cover areas near tiny Gulfport with 10 feet of water.
"I'm not going back after this one," 83-year-old Lois Russell said as she watched water surround her house near Gulfport. It was the third time she had fled her home because of flooding since 1965.
"It was a good place to raise my seven kids," she said, crying. "I know I haven't lost anything that feels important because I have a big family."
The situation in Gulfport is one of many across the upper Midwest that prompted President George W. Bush on Tuesday to pledge housing help and other federal aid to victims, as well as federal aid to farmers and ranchers.
The president plans to visit flood-stricken Iowa on Thursday, where heavy rains have washed out millions of acres of prime farm and grazing lands, raising the likelihood of higher food prices.
Illinois and Missouri towns are facing Mississippi River flooding that began in eastern Iowa and worked its way downstream.
The Iowa floods caused more than $1.5 billion in damage as they crept south toward the Mississippi.
Communities downstream are waiting on their crests later this week, including towns in southeast Iowa. Crests near St. Louis are expected to be near those of 1993.
Later this week, the Mississippi is expected to threaten a host of other communities, leading officials to consider evacuation plans and begin sandbagging.
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