BC Hydro dam project goes underground

Tunneling and underground cavern excavation is underway and expected to continue until April

Construction crews dig into the earth wall at the south end of what will be a long tunnel to accommodate a new underground John Hart Generating Station.

Blasting on the $1.1 billion John Hart Generating Station replacement project has moved underground.

Tunneling and underground cavern excavation is underway and expected to continue until April.

Stephen Watson, spokesperson for BC Hydro, said the south end of the tunnel has been carved out and is currently 10 metres long.

This tunnel will make way for a new, seismically-sound underground generating station.

Crews have also been busy making way for the construction of a new bridge crossing beside the existing Brewster Lake Road Bridge.

In the past month, several trees have been cleared on BC Hydro property off Brewster Lake Road.

“No logging occurred on BC Parks land,” Watson said. “About 20 hazard trees have been identified on BC Parks land and some will be removed (about 12), others will be topped or left as is. Any trees removed from BC Parks requires compensation planting and those details are being determined.”

The new bridge crossing will allow construction vehicles to make their way over the three penstocks, which will eventually be removed and replaced with a single, underground tunnel.

Construction is expected to begin on the penstock bridge crossing in April to coincide with the full closure of Brewster Lake Road and the old bridge, Watson said.

“Intermittent Brewster Lake Road closures of up to 15 minutes at a time will continue until March 2015,” Watson said. “In April, the planned three-year closure is expected to begin in full to accommodate the construction work relating to the underground generating station.”

Closures along the Millennium Trail are also expected to continue and be up to 15 minutes long. Watson said trail users will be advised by flaggers of any closures, which may come to an end before the end of this month.

Construction crews have also begun work on the west side of Powerhouse Road, which is the main road to the John Hart Generating Station.

“The area will be used as a laydown area for the project, allowing storage, equipment parking and assembly areas,” Watson said. “Tree clearing is complete.”

Construction crews begin tunnelling underground on the John Hart Dam upgrade.

Quick facts:

  • Roughly 185 people are currently working on the John Hart project.
  • About 50 local companies have provided services or supplies.
  • Final tally of frog relocations for 2014 was 69.
  • Environmental planning is underway for building of a cofferdam to facilitate construction of the new water intake at the concrete John Hart spillway dam.
  • Turbine/generator contract has been signed with Alstom.