YORKTOWN, Va. – Contractors barge in rock to be used in stabilizing the York River shoreline along 800 feet of the Colonial National Parkway here June 6, 2013. The area is part of more than four miles of shoreline that is in need of stabilization due to severe erosion, which is threatening portions of the parkway and the National Park Service’s Colonial National Historic Park. (U.S. Army photo/Patrick Bloodgood)