Chesapeake and Ohio Canal National Historical Park has closed the pedestrian bridge at Dam 4 Winch House (mile marker 84.6) to all traffic. During a recent inspection, engineers found that the walkway’s supports have wood deterioration due to rot, and the metal hangers for the walkway support beams have been severely corroded. The bridge provides pedestrian access from the parking area off of Dam No. 4 Road, over the historic stone stop-gate and canal to the left abutment of Dam 4. The . . .