DAKOTA DUNES -- Authorities on Friday morning warned hundreds of residents in southeast South Dakota to prepare to evacuate their homes in advance or rising floodwaters on the Missouri River.
Residents in Dakota Dunes, Riverland Estates, Wynstone, and adjacent rural residences were asked to secure their possessions and consider a volunteer evacuation by Union County Emergency Management and the county sheriff’s Department. A shelter is being set up by the American Red Cross at the Sioux City West Middle School at 3301 W. 19th St.
Due to heavily rainfall, snow melt, and unanticipated intake into Lewis and Clark Reservoir at Yankton, the U.S. Army Corps of Engineers has more than tripled water releases from Gavin Point dam in the last three days. Releases were raised to 80,000 cubic feet per second at noon Thursday and later to 90,000 cfs, and 100,000 cfs at 11 p.m. last night. At 5 a.m. Friday, levels were dropped back to 90,000 cfs.
Based on the new releases, authorities believe the Missouri River may reach elevations of 1,092 to 1,093 feet in Dakota Dunes area and 1096 to 1097 feet in The Wynstone development.
In Sioux City, the Missouri is forecast to crest 30.8 feet early Sunday morning, and the the Big Sioux River is expected to crest at 32.9 feet. At these levels, floodwaters may inundate low lying residential properties along the river.
Conditions will change rapidly. Additional measures may be taken as parameters change. Please monitor local media, Union County Sheriff’s Office Facebook page, and Union County website site.