St. Louis Levees Are Expected to Hold Mississippi

Water Volume Falls After Upstream Areas Inundated

Residents along the Mississippi River are experiencing the worst flooding in 15 years.
Washington Post Staff Writer
Saturday, June 21, 2008; Page A02

The crest of the flood-swollen Mississippi River moved steadily downstream toward St. Louis yesterday, but authorities said they expect levees there to hold -- in part because breaches and overflows upstream have reduced the volume of water in the river.

So far, the Mississippi floodwaters have overtopped 35 levees along the river, three of them since Thursday, said Suzanne Fournier, a spokeswoman for the U.S. Army Corps of Engineers.

Those overflows have inundated towns along the upper Mississippi, knocked out roads, bridges and rail lines, and swamped millions of acres of farmland, driving up the prices of corn, soybeans and other foods. But by dispersing the floodwaters produced by heavy rains in recent weeks, the overflows have slowed down the river and reduced the pressure on levees farther south.

"Right now we're watching the crest as it moves downriver," Fournier said in an interview today. She said the river is expected to crest at St. Louis tonight at 37 feet, well below the top of the 52-foot federal levees built there to withstand 100-year floods -- the type of inundation expected to occur, on average, about once a century.

"We have complete confidence that the East St. Louis levees will withstand" the crest, Fournier said.

Weather forecasters said the water level in the Mississippi now is about three feet lower than it could have been without the levee overflows upstream. That is significant for St. Louis, because the river had been projected to approach the major flood stage of 40 feet by early next week, according to the forecasting service.

During the devastating Midwestern floods of 1993, the river crested at St. Louis at more than 49.5 feet.

One potential problem is a wave of thunderstorms predicted to move into the mid-Mississippi Valley this weekend. Forecasters said the storms could complicate matters for people trying to recover from the flooding. But the weather was expected to have little impact on the overall situation.

"A slow-moving storm diving out of central Canada will produce rounds of spotty thunderstorms in the flood-ravaged region through this weekend, as the dry spell of weather in the Midwest comes to an end," said in a news release. "Thunderstorms will generally be spotty in nature; however, some locally heavy downpours could result in small stream or urban flooding."

The service predicted that Mississippi waters will hold steady at about 37 feet through this weekend before starting to drop. At Winfield, Mo., about 50 miles north of St. Louis, the water has hovered around 35.5 feet since a nearby levee broke late Wednesday. By next week, the level should rise about a foot as floodwaters that overtopped the levees drain back into the river, said.

Despite the generally more upbeat outlook, some river towns remain under threat. "There will still be a lot of places with major flooding," said National Weather Service meteorologist Jim Kramper, according to the Associated Press.

According to Fournier of the Army Corps of Engineers, many of the 35 levees that have overflowed "were never designed to handle the amount of water that is in the Mississippi right now." She said only seven of the levees were "federally authorized," while 24 were "non-federally authorized" and four were private levees. Federally authorized levees are usually higher and undergo annual inspections.

"Although the levees have been overtopped," Fournier said, "they really worked as intended, because they bought critical time to safely evacuate residents and, in some cases, provided a lot of protection for properties."

South of St. Louis, the Mississippi is much wider and deeper, minimizing the impact of the flooding upstream, she said.

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