The worst Midwest flooding in 15 years eased on Saturday after the swollen Mississippi River crested in St. Louis, but the toll was still rising as billions of dollars in damage to crops, communities and infrastructure were assessed.

Emergency workers at river levees and floodwalls feared more rain could swell river levels again and complicate recovery efforts. But the skies remained mostly clear and thousands of relief workers could finally exhale.

"It really is looking positive. The weather has cooperated and that's made a difference," said Maggie Carson, a spokeswoman for Illinois Emergency Management in Alton, Illinois, a few miles north of St. Louis.

Thunderstorms seen for the northern Midwest in the next few days were expected to be scattered and pose no new threat.

The flooding and storms blamed for 24 deaths since late May have caused billions of dollars in damage to the heart of the U.S. grain belt, pushing corn and other food commodity prices to record highs and feeding fears of higher world food prices.

Bridges and highways have been swamped, factories shut down, water and power utilities damaged, and the earnings of railroads, farmers and myriad other businesses disrupted.

Iowa and Illinois have been the hardest hit, but parts of Wisconsin, Minnesota, Indiana and Missouri have also been swamped. The runoff from torrential rains in the northern Midwest in late May and early June fed the Mississippi's southward torrent.

As the Mississippi crested, towns along the river's vast flood plain were left to tally their losses and wait for the waters to subside, which could take weeks or even months.

"Right now things are looking good. The crisis part is passed and that's heartening. We're breathing a sigh of relief," said Farm Bureau official Blake Roderick, executive director for Pike and Scott counties in Illinois.

River levels peaked in St. Louis at 37.27 feet (11.3 meters) late on Friday, lower than earlier forecast and well below the record of 49.58 feet set in 1993.

More than two dozen levee breaks up-river earlier in the week took pressure off downstream areas.

"St. Louis has crested. Everything is holding north of here," said John Daves, a spokesman for the U.S. Army Corps of Engineers in St. Louis.

No additional levee breaks were reported on Saturday. Sandbagging operations were halted in many communities, although the Illinois National Guard spent the day fortifying the low-lying town of Hamburg, Illinois, from high water.

Some 130 miles downstream from St. Louis, the nation's most important river is expected to crest at Cape Girardeau, Missouri, on Monday at 41.5 feet, also well below the 1993 peak of 48.5 feet.

Getting back to business as usual will take time.

Small towns and vast stretches of prime corn and soybean acreage have been submerged. Barge traffic remains halted on a 200-mile stretch of the middle-Mississippi River, costing barge carriers millions of dollars a day.

Up to 5 million acres of crops may have been lost to the world's top grain and food exporter. In Iowa alone, crop losses have been estimated at $3 billion.

Thousands returning to their homes face a toxic mess.

"We know from past experience that we will find E.coli, petroleum, gasoline, pesticides, household waste," said Thomas Dunne, an official with the Environmental Protection Agency's office of homeland security.

The economically depressed city of East St. Louis, located across the river from the Missouri city, appeared to have been spared a potential disaster as its outdated levees held.

President George W. Bush toured some of the devastation in Iowa on Thursday, and the White House said relief would be made available from $4 billion in the government's disaster fund.

Flood relief was rapidly becoming a political issue in a U.S. election year. Republican presidential candidate John McCain toured Iowa on Thursday, separately from Bush, while Democratic candidate Barack Obama helped stack sandbags earlier in the week in Quincy in his home state of Illinois.

Illinois Gov. Rod Blagojevich wrote to Bush on Friday, asking for faster aid for 20 flooded Illinois counties. In Iowa, 83 of 99 counties have been declared disaster areas.