The Gordon Dam is a double curvature concrete arch structure 140 m high, forming part of a hydro-electric scheme. The dam is sited on folded and faulted Precambrian quartzite. Driving adits was favoured over diamond drilling in siting the dam and for detailed investigations to prove the stability of the foundations.
Considerable excavation on the left abutment was necessary to remove unfavourable rock and a continuous pre-split face of 122 m was produced.
The geological conditions found during excavation were better than anticipated thus raising the computed factor of safety.