Roller-Compacted Concrete: Spring Hollow Dam, Roanoke County, Virginia

Abstract Only - The Spring Hollow Reservoir in Roanoke County, Virginia is currently being filled. The dam is the largest Roller Compacted Concrete (RCC) structure east of the Mississippi River and the nation's second highest completed to date. The 243-foot-high dam is the key element in a side-stream, pumped storage project undertaken by Roanoke County to meet its water supply needs well into the next century. Within a 4-month period in early 1993, over 300,000 cubic yards of RCC were mixed at the job site, placed by conveyor system, and compacted in 12-inch lifts behind a vertical upstream face of membrane-lined precast concrete panels.
This paper reviews how economy, function and dam safety led to the selection of an RCC dam and eliminated the need for an emergency spillway. This paper also reveals how the strategy used in the dam's design, the development of contract documents, and the contractor's selection assured a safe and functional dam yet achieved cost savings for the Owner by giving the contractor maximum flexibility regarding construction techniques and utilization of materials.