Missouri's Bootheel region, already hard hit by tornadoes and floods this spring, got the worst of Thursday's rain. Cape Girardeau received 3.3 inches of rain, Poplar Bluff 1.8 inches. Farmington, about 75 miles southwest of St. Louis, received 2.1 inches.
Rain was expected to end by midday Friday in Missouri, but was expected to continue throughout the day in portions of Illinois and Indiana. The National Weather Service said some areas of Indiana could be in for 3-4 more inches.
So far this month flooding has been blamed for nine deaths - eight in Missouri and the death Thursday of an 8-year-old Mason County, Ill., boy.
Christian Turner and two other boys were playing in floodwaters behind his house when their boat began to drift into a tributary of the swollen Illinois River, authorities said. Christian jumped out of the boat and drowned in about 6 feet of water.
In Crystal City, some merchants sandbagged as the Mississippi backed up through a normally shallow creek and flooded parts of the business district. Others, like a rental shop just down the road, moved everything out.
Missouri Gov. Bob Holden declared a statewide emergency, which frees up state resources to help flood-damaged areas. State emergency officials said more than half the state's 114 counties reported flood damage.
In Dutchtown, Mo., a Mississippi River town 120 miles south of St. Louis, workers from the Corps of Engineers and the county highway department, along with scores of volunteers, worked almost around the clock to build a makeshift levee out of crushed limestone.
A Coast Guard spokesman said the agency may close the Mississippi below Cape Girardeau, Friday night or Saturday, depending on weather and river conditions. The river would be closed to traffic to protect a levee from barge wakes on Illinois' southern tip.
The Illinois River was already closed to all boat traffic from Grafton, Ill., where it joins the Mississippi north of St. Louis, to Lacon, Ill., just north of Peoria.
A day after Gov. George Ryan declared the entire state a disaster area, Sen. Dick Durbin, D-Ill., sent a letter to President Bush on Thursday asking him to declare it a federal disaster area.
Over the past month, up to 10 inches of rain has fallen along the Illinois and Sangamon rivers. More rain was expected Friday.
Indiana Gov. Frank O'Bannon told CBS News he's worried about damage to homes, farms and businesses.
"Corn planting, soy bean planting is way behind, so it could be a disaster for the agricultural community," he said.
The governor reported numerous county roads and bridges along his helicopter route Thursday under water, homes isolated and farms swamped.
John Ogren, a meteorologist with the National Weather Service in Indianapolis, said there is no relief in the near future for swollen rivers and washed-out roads, not to mention frustrated farmers unable to plant spring crops.
"We really need about two weeks without any rain," Ogren said Thursday. "Unfortunately, it doesn't really look like we're going to get that."
By afternoon, the weather service issued a flood warning saying the White River might soon reach its highest flood crests in 41 years.
State Emergency Management Agency spokesman Alden Taylor said river communities across the state have been sandbagging in anticipation of rising water. The Department of Natural Resources, the state police and additional National Guard troops were on standby.