DES MOINES — Torrential rains pounded this flood-stricken city on Tuesday, threatening a crucial water treatment plant and raising fears of an outbreak of water-borne diseases, while the Mississippi River continued roaring out of its banks, swallowing farmland from Minnesota through Missouri.
Storms raked across Iowa, southern Minnesota and southwest Wisconsin Tuesday, pumping more energy into the cresting Mississippi River. Another rain belt formed to the south, across Nebraska, Kansas and Missouri, pouring water into the Missouri River. The effect, according to U.S. Army Corps of Engineers officials, will be to keep high waters battering levees for longer periods of time.
In the Omaha suburb of Papillion, an inch of rain fell in just six minutes. In Kansas City, Mo., two unofficial rain gauges showed half an inch of water streaming from the sky in less than 10 minutes.
And thunderstorms were expected to plow through the same areas again overnight, drenching some parts of the region with as much as six inches in a single day. The entire state of Iowa was covered by a flash flood watch Tuesday night.
"It's a very potent situation," said Jim Henderson, deputy director of the National Weather Service Severe Storm Forecast Center in Kansas City, Mo.
President Clinton said he would visit the region today on his way back to Washington.
Clinton told reporters in Hawaii that he had talked to Budget Director Leon E. Panetta about putting together an aid package. "Frankly, whatever we do, we are going to have to leave open the option of going back for more, depending on what the damage is. Those folks need some help."
Damage estimates in the Midwest top $3.5 billion. About 20 deaths have been blamed on the floods. Over 30,000 people have been evacuated, and some 18,500 homes are damaged. Over 8 million acres of land have been flooded. The Federal Emergency Management Agency said 222 Midwest counties and one city, St. Louis, have been declared federal disaster areas, and the Agriculture Department named 304 counties in six states eligible for emergency loans because of crop losses.
The ripple effect on the economy is also expected to be large, although experts predicted it would fall short of some other recent disasters, such as the drought of 1988 and last year's Hurricane Andrew. The Agriculture Department already has lowered its national corn and soybean harvest forecasts because of the flooding--by 7.6% for corn and 3.4% for soybeans.
The main trouble spots Tuesday were Des Moines and the battered levees along the Mississippi in Missouri and Illinois.
Thousands of volunteers armed with shovels joined National Guardsmen in massive sandbagging efforts to shore up roads, homes, businesses and the West Des Moines Water Treatment Plant, which has been donating drinking water to the flooded metropolitan area.
Drinking water for 250,000 Des Moines residents was contaminated when the Raccoon River surged over earthen levees and swamped the city waterworks last weekend. It may be a month before water filters and pipes can be disinfected and tap water is safe to drink, city officials said.
Until drinking water is restored, the Corps of Engineers and National Guard have set a target of trucking in 2.5 million gallons of water a day to the city and nearby communities.
That works out to about 10 gallons per day per person. As of Tuesday, residents were allowed up to five gallons of water at 60 distribution points, two gallons if they did not bring their own containers.
"We've suffered tornadoes, hailstorms and blizzards, but never anything of this magnitude," Des Moines Mayor John Dorrian said. "We have a grave concern about the flooding, but we're equally worried about its aftermath. That water is loaded with raw sewage, fertilizer, petroleum products and everything else."
Tuesday's early morning thunderstorms--the 38th downpour in 42 days--brought new flooding along the swollen Raccoon and Des Moines rivers, which merge downtown. The water overwhelmed city sanitation, firefighting, traffic and emergency medical services.
City and county officials estimated property damage so far at $250 million. That figure included at least 1,500 homes and 1,000 businesses in the Des Moines area that have suffered major flood damage.
Iowa Gov. Terry E. Branstad said on Tuesday that the entire state had been declared a disaster area, making low-interest loans and other aid available. The damage statewide was expected to exceed $1 billion.
City and county officials encouraged all residents, especially those who had come in contact with possibly contaminated river water, to take advantage of free tetanus shots being offered at clinics throughout the region.
"We think sanitation will be a bigger concern than the lack of water over the next few days," said John Durante, spokesman for the Des Moines General Hospital, which had yet to receive a water purification unit promised by U.S. Army National Guard officials.