RedactedNarrative: The operator and 5 passengers (2 adults 3 children) started a boat ride moments before 10 06/06/14. Vessel 1(la-5597-fn) was being operated at idle speed while exiting the breakwater of the bonnabel boat launch. The operator and passenger 1 (owner) were at the helm with the operator driving. As vessel 1 exited the break water the operator executed a turn (approximately 180 degrees) now heading west by northwest generally intending to go to the man-made reef structure on the west side of the causeway bridge. The operator noted that the steering felt a little "spongy" but was still steering effectively vessel 1 neared the causeway bridge and crossed beneath the northbound span while operating on plane. At this time the operator tried to make an adjustment to the boats steering. When he did this the steering wheel spun freely and the vessel was heading toward a piling. The operator tried to reduce throttle however the vessel was unable to avoid collision. The vessel struck one of the support structures of the bridge on the port side bow. Passenger 2 was thrown forward and sustained head injuries from either the bridge piling or a portion of the vessel (unknown). passenger 3(male-minor) was wearing a pfd and was recovered by the operator seconds after ejection. Vessel 1 came to a stop. Emergency units present on the bridge lowered a cage to hoist passenger 2 from the vessel. All minors were wearing pfd's required by law. both the operator and passenger 1 consented to give blood samples as they both admitted to driving the vessel at times this day. The blood samples will be delivered to lsp crime lab for analysis. There was no indication of intoxication of any kind on the scene. Intoxication is not suspected to be a contributing factor(results of analysis pending).