Construction History
From the Archives: July 22, 1954
This 1954 image depicts the excavation of an 8,000-ft-long channel to carry water downstream from the Roanoke Rapids Dam powerhouse in North Carolina.
The excavation subcontractor, Central Engineering and Construction Corp., of Durham, N.C., employed an interesting method to carve the 80-ft-wide channel, which is 56 ft deep at the powerhouse and 31 ft at its outlet downstream.
A drill carriage with 14 wagon drills abreast mounted on it was shoved along on rails to drill the blast holes for the first lift.
This rig, basically a jumbo, positioned the drills to drill 24-ft to 30-ft-deep blast holes. After the first lift was blasted and mucked clean, the rock surface was too uneven for further use of the jumbo, and individual drills (seen in the cover photo above) took over.
A million cu yd of granite was removed. Although the granite excavated was not suitable for use as aggregate for the dam, it was used to build a dike parallel to the tailrace to keep out the river’s flow.
The dam’s power generating capacity of 95 MW was 20% greater thanks to the higher head provided by the tailrace. The dam was built by Virginia Electric and Power Co., now known as Dominion Energy. It was completed in 1955.
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