Millrace Rapids is a popular kayaking playspot, located on the Lower Saluda River in Columbia, South Carolina.
The rapids are a result of the Saluda River running over the remains of a twice-dynamited coffer dam.
Because the lower Saluda is flow-controlled by a hydroelectric dam (operated by Dominion Energy), the water level can change rapidly. There is a warning system in place that consists of a series of sirens and strategically placed markers.