David Jarvis, an engineer with the U.S. Army Corps of Engineers - Tulsa District, inspects the gates on R.S. Kerr Lock and Dam (#15) as part of a periodic inspection. Droesch is using the rope access technique, which allows him access to areas he would not have easily accessed by using the fall arrest method. Rope access allows the inspectors to ascend and descend via ropes, while fall arrest requires them to scale the structure with only a safety line to keep them from falling. (photo by Thomas Mills USACE)