But the water also carries an extra curse Tuesday as a slick of 42,000 gallons of thick crude oil floated downstream with the mud and debris, coating everything it touched with a slimy, smelly layer of goo.
"My question is how are they going to get all that oil out of the environment," said Mary Burge, a heart surgery patient who had to breathe from a portable oxygen tank because the petroleum odor Monday was so strong it could be detected by the crews of helicopters passing overhead.
A malfunction allowed the oil to spill from the Coffeyville Resources refinery on Sunday, while the plant was shutting down in advance of the flood heading toward it on the Verdigris River.
Though the water was beginning to recede early Tuesday, it was still too high to allow anyone into the refinery, said Jim Miller, Montgomery County emergency manager.
"The water is still going into the refinery," Miller said. "As far as access to that, just nobody is going in there."
The Verdigris River had crested but the water level remained high because water was still being released from the Elk City and Fall River Toronto Lake reservoirs farther upstream, Miller said.
"It's going to come down the Verdigris until they shut that water supply off," he said. "So it's just a matter of time."
Anything that got wet is likely ruined, including the contents of Dick Trotter's mother's house.
"It's hard to describe because I can sit back remembering when I did this and that, and now it's gone," Trotter told CBS affiliate KWCH-TV.
Cleanup of the toxic sludge will complicate long-term flood recovery efforts for Coffeyville.
The oil also is a concern for others downstream. The U.S. Environmental Protection Agency had teams on the scene and was monitoring the oil slick as it floated toward drinking water sources and recreation areas in Oklahoma, said Jim Miller, the Montgomery County emergency manager.
By midday Tuesday, the oil was nearing a large Oklahoma reservoir that supplies water to several cities, including Tulsa.
Sharon Watson, spokeswoman for the Kansas adjutant general, said the EPA and state officials would work with officials at the refinery to measure the amount of contamination and help the refinery clean up. In the meantime, however, Watson said, "We're asking everyone to avoid the floodwaters."
That wasn't an option for Fire Department Capt. Mike Mansfield, who rescued eight dogs from water-logged homes Monday. He said all the dogs found outside were covered in oil.
The oil was floating down river toward Oklahoma and that state's Oologah Lake, about 30 miles northeast of Tulsa, said Maj. Gen. Tod Bunting, the Kansas state adjutant.
However, Oklahoma officials were optimistic the spill would dissipate before it reached the lake, which provides flood control, drinking water and recreation.
"There are nine public water supplies along the Verdigris and the Oologah Lake, and none of them are currently affected," said Skylar McElhaney, a spokeswoman for Oklahoma's Department of Environmental Quality. Tulsa is among the cities that get water from Oologah.
The oil joins other causes of misery for thousands of flood evacuees in Kansas, Oklahoma and Texas.
"We do have health concerns," said Bret Glendening, city manager in Osawatomie, Kan. "You've got stagnant water. The water's been into the wood. You have mold issues. There's a whole host of concerns."
"I've lived here 37 years, and I've never seen this. It's one of the worst I've ever seen," resident Ben Bewendt said.
"Our building, our particular building, has water about a foot from the top of the window is where it leaves off. So we've pretty much lost everything except for beds and dressers that are upstairs. Everything else was downstairs," said Beth Sears. "We got a few clothes out, and a few photo albums, but everything else is lost."
"All our utilities are under water," Fredonia Mayor Max Payne said.
On Monday night, President Bush declared a major disaster in Kansas and ordered federal aid for recovery efforts.
Eleven deaths have been blamed on weeks of heavy rain and flooding in Texas, where two men are missing.
More thunderstorms hit parts of Texas on Monday, flooding some roads. The National Weather Service said about 10 inches of rain fell by noon at Corpus Christi.
Tuesday "will be just like yesterday, as thunderstorms will build over the region, with a few places probably picking up two to five inches," says CBS News meteorologist George Cullen.
"Been out of our house for six days since they shut the power off and we've just been shuffling around from hotel to hotel," Parker County, Texas, evacuee Nathan Bryant said. "We're just about homesick."
Two youngsters were rescued from an Arlington, Texas, drainage channel, one after floating half a mile downstream through at least three viaducts, said Fire Department Battalion Chief David Stapp. A handful of people had to be rescued from flooded homes in Laredo.
In North Little Rock, Ark., about 30 homes were evacuated Monday when heavy rain and a faulty drainage system caused flooding up to six feet deep in some spots.
The weather and floods have squelched summer recreational activities across the Plains, slowing business at parks and tourist destinations and waterlogging campsites and hiking trails.
A year ago, many Texas officials warning boaters about lakes that were too low and banned fireworks because the ground was too dry. Now some popular lakes might be closed for the Fourth of July because they're too full, and fireworks shows are threatened by a continuing forecast of rain.
Texas has had to close three state parks temporarily.
"Obviously it's going to impact numbers. People don't want to go camping when it's pouring down rain," said Rob McCorkle, a spokesman for the Texas Parks and Wildlife Department.