RedactedNarrative: Vessel 1 Operator was motoring north on pool nine toward Lock and Dam 8 on the Mississippi River near Genoa, Wisconsin. The Operator was unaware of a wing dam that is located approximately a half mile south of the lock. The Operator motored over the wing dam. The vessel’s lower unit impacted the wing dam structure below the surface of the water causing the boat to lose power. None of the four occupants on board were injured in the incident.