Blue Ridge Low Level Outlet


Tennessee Valley Authority

Completion Date



McMillen Jacobs Associates


Fannin County, Georgia

Delivery Method

General Contractor


Blue Ridge Low Level Outlet

Blue Ridge Low Level Outlet project updates the hydroelectric dam in north Georgia originally constructed in 1925. Standing 167 feet tall and spanning 1,000 feet, the dam's primary purpose is to generate electricity and manage flood damage along the Toccoa River.

As part of the effort to improve water level regulation for the Blue Ridge Reservoir, Atkinson built a low-level inlet/outlet structure within the dam's infrastructure. This included the careful design and construction of a 975-foot-long tunnel with a 12-foot diameter, a 105-foot sheet pile cofferdam, the installation of flow control devices, and the integration of hydraulic energy dissipation systems. During excavation, the team used traditional drill and blast techniques. The dam's intake structure also included a 16-foot-diameter by 50-foot steel intake liner, trashracks in the reservoir, and a 9-foot-diameter by 1,000-foot steel pipe designed to accommodate flows of 1,800 cubic feet per second at a head opening of 130 feet, all encased in cellular concrete. Atkinson built the intake structure using marine equipment, with tunneling teams subsequently connecting the tunnel to the intake structure to finalize the project.