The uninspected towing vessel Stephen L. Colby struck hard bottom in the Upper Mississippi River (UMR) and partially sank off the right descending riverbank in LeClaire, Iowa, on November 25, 2013, at 1555 central standard time. Six of the nine crew-members on board made it to the riverbank on their own. The nearby towing vessel Aaron F. Barrett recovered the remaining three crewmembers from the partially sunken vessel. No one was injured.
The National Transportation Safety Board determines that the probable cause of the grounding and sinking of the Stephen L. Colby was the failure of the master and mate to ensure sufficient underkeel clearance for the intended transit through the accident area.