Big Sioux River
Catchment area of the Big Sioux River
Falls in Sioux Falls
The Big Sioux River rises in Roberts County, South Dakota. Then it flows through the County's Grant, Codington, Hamlin, Brookings, Moody and Minnehaha. In Sioux Falls, the river forms a waterfall, which gave its name to the city. According to Brandon, the river flows along the border of the two states.