In 2013, the Waneta Tunnelers Partnership (Redpath/Frontier-Kemper) completed the construction of two (2), parallel Penstock Tunnels using Drill-and-Blast methods. This project expanded the capacity of the existing 450 Megawatt (MW) Waneta Dam by installing a second Powerhouse to generate up to 335 MW from water that was being spilled over the dam. Our scope of work included:
(2) 32.8-ft. diameter, parallel Penstock Tunnels
Tunnels run uphill at 14% and 17% grade
Lengths: 675 LF & 660LF
(1) 20 ft. x 20 ft. Access Adit, 374 LF
Tunnels were lined with 300mm thick, cast-in-place, concrete liner