Wednesday, March 17, 2010

Tunnel Boring Machine to Reach North Shaft Very Soon!

The Tunnel Boring Machine (TBM) boring the New Crystal Springs Bypass Tunnel is expected to reach the North Shaft site very soon!
The project team expects the TBM to finish boring next week - most likely on or around the 25th of March.
The TBM is boring a 4,200 foot long tunnel for a critical water pipeline that will help ensure water delivery after a major earthquake.
We will keep you updated on the tunnel completion and next steps in this important project.


  1. Well good to see you are about done. The noise,dust,disturbances have not been quite as bad as expected. Now I was under the impression during the beginning meetings that all dirt would be removed from the site and land restored with trees and flowers when finished. Then the other day speaking with someone when finished all dirt will remain, That means the "floor" has been raised, which also brings up the question, how high has the floor risen?
    Just curious and will post other comments in regards to this project soon.

  2. Thank you for your comment. Good news - tunnel excavation is now complete as of March 24th.
    The materials removed from project excavations (also referred to as muck) have added approximately 8 feet so far to the upper terrace of the South Shaft site. The bulk of the excavated muck is now there. With the addition of some muck from a few more activities, we expect the muck to raise the surface of the terrace by a total of about 10.5 feet.
    The muck disposal area will be graded and seeded with native grasses this summer or prior to the next rainy season. No bushes or trees will be planted.

  3. What's with all the new dirt piles? Are they to remain or will they be removed? I thought with the digging of the tunnel complete the dirt piles were complete. if this dirt is not removed, and just spread out this will bring the "floor" up higher as was suggested before this project was started. Hmmmmm.

  4. Thanks for your comment. The tunnel excavation has been completed and the contractor is currently excavating for the South Shaft vaults and pipeline. The temporary dirt piles on the upper terrace will be used to backfill the vaults and pipeline excavation. If there is surplus dirt, the dirt will be added to the muck pile and included in the final grading and revegetation plan. The upper terrace work is expected to be completed by Fall 2011.

  5. Now what is with the dirt berm that has been built in front of the cement water storage(swimming pool)? Is it still the plan to remove everything from the field when the pipeline is done, or is the berm to hide the cement water storage?

  6. Sorry for the delay in responding, we did not get your message until today. We will respond asap.

  7. The dirt berm above the temporary construction water treatment plant is also temporary. That dirt will be used to fill in the areas currently occupied by the trailers and treatment plant. All trailers and equipment will be removed from the field at the end of the project (planned for Fall 2011). There will be a few permanent cement vaults near Polhemus Road. Thank you and Happy Thanksgiving!