Shimmick Crane Operator Patrick Harrison lifted the last concrete form from monolith L13 to mark the official completion of the first of 36 monoliths. The U.S. Army Corps of Engineers Nashville District and its contractor, Shimmick, held a topping-off ceremony May 22, 2023, at the Chickamauga Lock Replacement Project on the Tennessee River in Chattanooga, Tennessee. (USACE Photo by Lee Roberts)