Paul Hellstern/The Oklahoman/AP
Riley Webb hands her 7-month-old baby to Oklahoma County Commissioner Willa Johnson after being rescued by fire department personnel from a flooded mobile home park in Midwest City, Okla., June 1, 2013.
Heavy rainfall caused severe flooding in the region.
John Badman/The Telegraph/AP
An aerial photo shows the Riverfront Park amphitheater complex in Alton, Ill. surrounded by Mississippi River floodwaters on three sides, June 4, 2013.
The river crested Tuesday but more rain is expected Wednesday and Thursday.
Paul Hellstern/The Oklahoman/AP
Fire department crews use boats to rescue residents from a flooded mobile home park in Midwest City, Okla, June 1, 2013, after up to eight inches of rain fell during the previous 24 hours.
Derik Holtmann/Belleville News-Democrat/AP
A boat passes the St. Louis riverfront and the steps to the Gateway Arch, June 4, 2013.
The Mississippi River crested at 40.52 feet as of Tuesday afternoon in St. Louis, the sixth-highest level recorded here since 1785.
Derik Holtmann/Belleville News-Democrat/AP
Louis Hall, 64, of St. Louis took advantage of the high water on the Mississippi River to fish for Blue Catfish along the bank on the East St. Louis riverfront, June 4, 2013.
John Badman/The Telegraph/AP
Floodwaters surround the Argosy Casino complex in Alton, Ill, June 4, 2013.
The casino has been closed because of flooding since early Sunday and does not expect to re-open until at least Friday.
Nati Harnik/AP
Following heavy rain, a field in Percival, Iowa, is becoming flooded, May 29, 2013.
The corn crop in this same field was devastated by last year's drought. Rivers in the nation's heartland are rising again, and with heavy rain in the forecast, parts of the Midwest are bracing for yet another round of flooding.
J.B. Forbes/St. Louis Post-Dispatch/AP
Dan Diehl shows his grandson, Tyler Vaughn, 7, how to cast a fishing lure into the flood waters of the Meramec River in Fenton, Mo., June 4, 2013.
John Badman/The Telegraph/AP
Workers from the ConAgra Mill in Alton, Ill., boat down West Broadway to work on, June 4, 2013. West Broadway, also known as the Great River Road, is closed because of floodwaters from the Mississippi River.
J.B. Forbes/St. Louis Post-Dispatch/AP
Volunteers add sandbags to a temporary flood wall in Kimmswick, Mo., to try and stop the flood waters of the Mississippi River from inundating the tourist town, June 4, 2013.
Nati Harnik/AP
Following heavy rain, young stalks of corn stand in a flooded field in Auburn, Neb., May 29, 2013.
J.B. Forbes/St. Louis Post-Dispatch/AP
Volunteers build a flood wall next to homes to stop the waters of the Mississippi River from inundating Kimmswick, Mo., June 4, 2013.
J.B. Forbes/St. Louis Post-Dispatch/AP
Andrea Vaughn, 8, and Tyler Vaughn, 7, try to fish in the flood waters of the Meramec River in Fenton, Mo., June 4, 2013.
Nati Harnik/AP
Young stalks of corn stand in a flooded field in Auburn, Neb., May 29, 2013.
J.B. Forbes/St. Louis Post-Dispatch/AP
Volunteers add sandbags to a temporary flood wall in Kimmswick, Mo., June 4, 2013, to try and stop the flood waters of the Mississippi River from inundating tourist town.
Derik Holtmann/Belleville News-Democrat/AP
The Kaskaskia Rver has overtaken the parking lot to Smitty's at the Marina in New Athens, Ill., June 3, 2013.
The Kaskaskia River was more than seven feet above flood stage on Monday in New Athens.
John Badman/The Telegraph/AP
A man stands on the railroad viaduct entrance to West Alton, Mo., June 4, 2013.
A levee break flooded nearby highways Monday evening and residents were ordered to evacuate the town as a precaution. Officials dumped dirt and rock on the highway at the viaduct to stop floodwaters from getting into the small community.
John Badman/The Telegraph/AP
An aerial photo shows the flooded southbound lanes of U.S. Highway 67 after a levee broke Monday, June 4, 2013. The flooding closed the southbound lanes of the Clark Bridge, top, in Alton, Ill., to all traffic.
John Badman/The Telegraph/AP
A stop sign stands above the water on U.S. Route 67 in West Alton, Mo., June 4, 2013.
A levee broke Monday evening flooding the lower portion of the highway and closing the southbound lanes of the nearby Clark Bridge in Alton, Ill.
John Badman/The Telegraph/AP
An aerial photo shows flooding at the intersection of Illinois Routes 100 and 3 in the center of Grafton, Ill., June 4, 2013. The rivers crested Tuesday but more rain is expected Wednesday and Thursday.