Swollen rivers in the US Midwest and other regions brought flood warnings for over 12 million Americans on Wednesday as scores of buildings were submerged after days of intense rain in which 24 people have died.
Two rivers west of St. Louis crested at historic levels, flooding local towns, disabling sewer plants and forcing the evacuation of hundreds of residents.
Other major rivers including the Mississippi are expected to reach record highs as flood waters rush toward the Gulf of Mexico, the National Weather Service said.
The flooding has closed many roads and parts of Interstate 44, a major artery running from west Texas to St. Louis. It poses a threat to livestock and crops in farm areas stretching from Illinois to Louisiana.
Water rose to the rooftops of homes and businesses in Missouri, where Governor Jay Nixon called the flooding “historic and dangerous.” Nixon spoke with President Barack Obama on Wednesday and received a pledge of federal support.
About 300 people in Valley Park, Missouri, west of St. Louis, were evacuated in case a levee is breached on the Meramec River, said Chief Rick Wilken of the Valley Park Fire District. Residents in West Alton and Arnold, at the confluence of the Mississippi and Missouri rivers, and the town of Pacific have also been evacuated.
At least 24 people have died, mostly from driving into flooded areas, in Missouri, Illinois, Arkansas and Oklahoma after days of downpours with as much as 12 inches (30 cm) of rain.