South Dakota Game, Fish and Parks officials have cautioned boaters about limited water releases from the Fort Randall Dam near Pickstown and Gavin's Point Dam near Yankton.
In an effort to control flood waters, officials have decreased dam flow. The result is a drop in river elevation below the dams. Department officials ask boaters to be wary of hazards in the shallower waters.
The U.S. Army Corps of Engineers Northwestern Division on Tuesday had announced decreased water releases from Gavin's Point Dam.
Record rainfalls have inundated the southeast corner of the state this month, causing floods.
Boating access is still available on Lake Francis Case and Lewis and Clark Lake.