At the borders of South Dakota, Iowa and Minnesota, floodwaters rose over several days.
In the Sioux City, Iowa, area, a huge train bridge collapsed into the Big Sioux River late Sunday, an emergency manager said.
The bridge connects North Sioux City, South Dakota, with nearby Sioux City, Iowa, Jason Westcott, an emergency manager in Union County, South Dakota, told KCAU-TV. Some of the trusses collapsed, Westcott said.
Images from local media show a large span of the steel bridge partially underwater as floodwaters rush over it.

In northwest Iowa, 13 rivers flooded, said Eric Tigges of Clay County emergency management. Entire neighborhoods, and at least one whole town, were evacuated, and the Iowa town of Spencer imposed a curfew Sunday for a second night after flooding that surpassed a record set in 1953.
“When the flood gauge is underwater, it’s really high,” Tigges said at a news conference organized by Spencer officials.
Gov. Kim Reynolds declared a disaster for 21 counties in northern Iowa, including Sioux County. In drone video posted by the local sheriff, no streets were visible, just roofs and treetops poking above the water.