The Ohio River at Cincinnati was expected to rise about 2 feet above flood stage by Friday. In nearby Whitewater Township, rescue workers with boats helped 16 people to safety.
"You don't have no choice, you've got to go," Whitewater Township resident Judy Booth, who was helped by fire-rescue squads who brought an inflatable boat to her water-surrounded home, told the Associated Press.
Flooding was also reported Wednesday in parts of Arkansas, southern Illinois, southern Indiana, Missouri and Kentucky.
At least 13 deaths have been linked to the weather, and three people remain missing. The rains began in force on Monday.
Five deaths were blamed on the flooding in Missouri, five people were killed in a highway wreck during heavy rain in Kentucky and an Ohio woman appeared to have drowned while checking on a sump pump in her home, the AP reported. In southern Illinois, two bodies were found hours after floodwaters swept a pickup truck off a rural road.
President Bush declared a major disaster in Missouri on Wednesday night and ordered federal authorities to aid local recovery efforts. Seventy counties and the city of St. Louis also are eligible for federal funding for emergency protective measures.
The National Weather Service was forecasting record flooding along the Meramec River near St. Louis. The Black, Big and St. Francis rivers in southeastern Missouri also were expected to see significant flooding.
"Right now we're in flash flood response mode - water rescues, evacuations," a spokeswoman for the Missouri Emergency Management Agency, Suzie Stonner, told The New York Times. "It's been ongoing almost continuously since yesterday. The ground is so soaked that the water just runs off. We're going to go into a massive flooding situation soon."
Local weather watchers fear that the already saturated ground could spell continued problems as the spring season brings more rain.
"The next couple of months," meteorologist Mark O'Malley of the National Weather Service in Pleasant Hill, Mo., told the Kansas City Star, "could really be problematic."
