Big Sioux

The Big Sioux River in Dell Rapids splits and the bigger half of the flow drops into the canyon known as the Dells of the Sioux.  The majority of the canyon is quite flat.  Rapids are found at the top of the canyon.  Depending on flows it could reach Class III especially considering that a swim will put the boat into a very steep sided canyon. This run is hard to get off early because of the canyon walls so paddlers wanting to float the Dells will probably want to boat all the way to the bottom.