Two kayakers got caught in the wash of the Dock Street Dam on the Susquehanna River in Harrisburg. Rescuers were able to pull both from the water without injury. It appears they went over the dam on purpose, but underestimated the downstream current generated as water rolls over the low-head dam. The Dock Street Dam runs across the Susquehanna River between Harrisburg and Lemoyne.
The Fish and Boat Commission website says people often overlook the power of the water at low-head dams. Anything caught in the backwash generated below the dam is trapped and recirculated round and round, making escape or rescue difficult. A person caught in the backwash of a low-head dam in certain flows will be carried to the face of the dam, where water pouring over it will wash him back under the water and back beneath the boil. When the victim struggles to the surface, the backwash again carries him to the face of the dam, thus continuing the cycle. For more information on low-head dams, click here.