June 20 (Bloomberg) -- The Mississippi River breached more than a dozen levees in Missouri, flooding farmland and causing hundreds of residents to flee homes.

The overflowing waterway may ensure that the flood, triggered by as much as 15 inches (38 centimeters) of rain in some parts of Iowa this month, will crest at lower levels downstream than previously forecast and fall short of record levels set in 1993.

``If you have a bathtub full of water and someone comes along with a sledgehammer and knocks out a six-inch chunk of the bathtub, the crest in the bathtub will go down,'' said Alan Dooley, spokesman for the Army Corps of Engineers in St. Louis.

Floods and severe weather along the Mississippi River have killed 24 people, forced more than 38,000 from their homes and inundated at least 3.4 million acres in three states, an area larger than Connecticut. It has closed a 388-mile (624- kilometer) stretch of the river from Iowa past St. Louis to recreational boat traffic and limited commercial shipping.

The levees breached north of St. Louis were agricultural levees built to withstand 30-year floods at most, Dooley said. The failure of those structures may flood 20,000 acres of farmland and ruin homes, he said. As the water streams over levees, it will cause river levels to drop and accelerate the crest downriver, he said.

The Mississippi has breached or overtopped 14 levees in Missouri, according to Susie Stonner, a spokeswoman for Missouri State Emergency Management Agency in Jefferson City.

Residents Flee

The water flowed over three levees around the city of Winfield, about 40 miles northwest of St. Louis. The river is at 35.6 feet (11.2 meters) at Winfield, almost 10 feet above flood stage, and forecast to rise. All but 25 of Winfield's 700 residents followed the state's advice to leave their homes, Stonner said.

The breached levees meant some relief for Clarksville, Missouri, just upstream, said City Clerk Jennifer Calvin.

``I hate it for them but I love it for us,'' Calvin said in a telephone interview.

The city of 500, which changed itself in the last few years into a haven for artists and antique dealers, lined up portable toilets on each block this week as the community's sewage treatment failed and an influx of volunteers doubled the local population. Calvin said she took her first plane ride yesterday, flying over the community to survey the damage.

Below-Record Crest

The river at Winfield and other points north of St. Louis may climb again in the next few days as water that poured over levees drains back into the Mississippi, according to AccuWeather.com.

The latest forecasts mean peak flood levels will be at least a foot below records set for the Mississippi in 1993 at cities along the river, including Quincy, Hannibal, Louisiana and Clarksville.

At St. Louis, the river was at 37.03 feet today, and may crest at about that level today, falling short of the 40-foot peak level the National Weather Service had predicted earlier this week for Missouri's second-biggest city. The record level for the city was 49.6 feet in 1993.

FEMA's Response

Storms this month in the Midwest have caused the worst flooding in 15 years, killing at least 24 people and injuring 148, the U.S. Federal Emergency Management Agency said this week.

Corn prices reached a record this week as the water swamped crops. The most active corn contract has gained 87 percent in the past year, reaching a record $7.915 a bushel on June 16. Soybean prices approached a record high this week.

U.S. President George W. Bush yesterday visited areas of Iowa soaked by record flooding last week, including Cedar Rapids, where about 20,000 evacuees have begun returning to their homes. FEMA has provided 3.2 million liters (844,000 gallons) of water to the flood zone, enough for almost a half- million people daily, and material including 12.8 million sacks for sandbagging.

FEMA has paid out $33 million to 32,000 people registering for housing or other forms of assistance, said Harvey Johnson, FEMA deputy administrator, at a Washington press conference.

Iowa's Loss

Iowa may have lost $3 billion worth of corn and soybeans, according to Dave Miller, the Iowa Farm Bureau's director of research and commodity services. About 1.3 million acres of corn are flooded or remain unplanted and 2 million acres of soybeans are affected, representing about 16 percent of the state's farmland, he said.

There are at least 100,000 acres of farmland underwater in Illinois and Missouri combined, according to officials in those states.

Recreational river traffic has been stopped from Clinton, Iowa, to just south of St. Louis and commercial shipping is under restrictions, U.S. Coast Guard Chief Warrant Officer Brandon Brewer said from St. Louis.

Ships must sail at their slowest possible speed to minimize wakes that could put pressure on levees, he said.

In Iowa, the flood crest has passed and the cleanup has begun, though the Mississippi is still above flood stage in the state and will be for days to come, said Bret Voorhees, a spokesman for Iowa Homeland Security and Emergency Management.

To contact the reporter on this story: Brian K. Sullivan in Boston at bsullivan10@bloomberg.net; Robin Stringer in New York at rstringer@bloomberg.net

Last Updated: June 20, 2008 15:49 EDT