The exodus in the Mississippi River Valley crept southward as floodwaters continued to wreak havoc Thursday, forcing thousands from their homes amid some of the region's worst flooding in living memory.
Residents near the Mississippi and its tributaries packed their belongings and emergency workers filled sandbags to hold back the water that threatened to top levees and break records, some dating back to the 1920s.
"I've never seen it this bad," said 78-year-old Joe Harrison, who has lived in the same house in Hickman, Ky., since he was 11 months old. That house is now an island surrounded by flood water. He has been using a boat to get to his car, parked on dry ground along a nearby highway.
Hickman's Fulton County Jail put 120 inmate volunteers into action against the rising water. Dressed in orange or white prisoner uniforms, they furiously filled sandbags to bolster the earthen levee that adjoins the town's floodwall.
A sergeant at the jail, James Buckingham, said the inmates have made 120,000 sandbags since April 26.
"We're just going to keep going until they say stop," Buckingham said.
Nearly 4,000 people in western Kentucky have left their homes, while hundreds more have evacuated from southern Illinois and southeast Missouri.
Most have found refuge with family and friends, but some, like Ashley Latham of Paducah, Ky., were living at Red Cross shelters.
"I don't think there's going to be an opportunity for us to go back to our house, because our house that we lived in was 50 years old and it was a cinder-block house," said Latham, who brought her five children to the shelter about a week ago. "I don't think there's going to be much left of it after this flood has hit it."
President Obama on Wednesday declared parts of Tennessee, Mississippi and Kentucky disasters, making the states eligible for federal help with relief efforts. It does not cover individual assistance.
Meanwhile, up and down the river nicknamed the Big Muddy, farmers braced for the destruction of more levees — a repeat of the desperate strategy employed earlier this week in which the Army Corps of Engineers blew up a Missouri levee and sacrificed vast stretches of farmland to protect the city of Cairo, Ill., and nearby populated areas.
It helped, but it wasn't enough.
Experts said the relief from blowing up the levee near Cairo was probably only temporary, because the water that burst through and flooded tens of thousands of acres, would eventually find its way back into the Mississippi River, threatening areas downstream.
Forecasters and emergency officials said some of the high-water records set during the great floods of 1927 and 1937 could fall. On Wednesday, for example, the Mississippi eclipsed the 46-foot mark set in 1937 in Caruthersville, Mo., and the water was still rising, with a crest of 49.5 feet forecast for Sunday.
But because of the system of levees and locks built since those disasters more than 70 years ago, flooding this time is unlikely to be anywhere near as devastating.
"We have a high confidence in our levees, but in the sense of transparency, we have to say that the levees have not been tested," Shelby County Emergency Management Director Bob Nations said in Memphis, Tenn.
Tom Salem, a meteorologist with the National Weather Service in Memphis, said flooding is extreme this year in part because of drenching rain over the past two weeks. In some areas, Wednesday was the first day without rain since April 25.
"It's been a massive amount of rain for a long period of time. And we're still getting snowmelt from Montana," Salem said.
In Arkansas, a 23-mile stretch of westbound Interstate 40 was closed where it crosses the White River, adding a detour of about 52 miles to the route between Little Rock and Memphis. Eastbound traffic will eventually face an even longer detour.
Arkansas recorded its eighth death since the rains started April 25. Authorities found the body of a man in the floodwaters in eastern Arkansas' Prairie County.
In Kentucky, about 3,800 residents have left their homes.
Memphis, where the Mississippi was at 43.8 feet Tuesday, could see a crest of 48 feet on May 11, just inches below the record of 48.7 feet set in 1937. Water from the Wolf and Loosahatchie rivers already has seeped into the suburbs, and some mobile home parks were swamped.
Emergency management officials said more than 1,100 houses and apartments could be hit with flooding. Several hundred people have already been evacuated, and thousands more are expected to do the same.
In Louisiana, shippers, ports and the chemical industry are hoping the government can dredge fast enough to keep a major channel into the Gulf of Mexico unclogged. The Mississippi sends huge amounts of sediment downriver during high-water times.
Because the maximum-security Louisiana State Penitentiary at Angola is particularly flood-prone, the state plans to evacuate the most medically vulnerable inmates by Monday, then other inmates later.
Mississippi officials told about 1,000 people packed into a National Guard armory Wednesday that they are confident the main levees along the Mississippi River will withstand high water in the coming weeks, but they warned that some backwater levees could be overtopped by as much as a foot.
Mississippi Gov. Haley Barbour warned people to expect monumental flooding and said he was moving his furniture from his family's lakeside home to prepare for flooding from the Yazoo River.
The great flood of the lower Mississippi River Valley in 1927 was one of the biggest natural disasters in U.S. history. More than 23,000 square miles were inundated, hundreds of thousands of people were displaced and hundreds died.
The flood found its place in folklore, literature and films, and popular songs including "When the Levee Breaks" were written about the disaster.
More devastation came in 1937 when 31,000 square miles were submerged from West Virginia to Louisiana.
With reporting from Angela Hatton of member station WKMS in Murray, Ky. Material from The Associated Press was used in this report.