Thursday, December 31, 2009

Possible Night Work in early January

The New Crystal Springs Bypass Tunnel contractor has been making necessary adjustments to the tunnel boring machine (TBM) inside the shaft. In early January 2010, limited crews may work into the evening. If night work needs to occur, we will provide dates and times as soon as possible. If the contractor continues to need more time to meet the project schedule, crews could work longer evenings going forward into the early Spring.

During this night work, the majority of activities take place inside the shaft and tunnel. The crane and site lights may be used. The project team will follow all required nighttime noise limits as specified in the project Environmental Impact Report (EIR). Some soil may be lifted from the shaft but will not be relocated to the upper terrace until the following daytime shift.

We will continue to have on-call staff monitoring the situation. You may call our 24 hour dispatch 650-872-5900.

Monday, December 28, 2009

New Video Highlights WSIP Progress

Here is a new video highlighting the progress we are making in rebuilding and seismically retrofitting the Hetch Hetchy water system.


Tuesday, December 22, 2009

North Shaft Update

At the North Shaft Site of the New Crystal Springs Bypass Tunnel project, vault work is nearing completion.

The valves and pipes within the vault have now been installed and the cast-in-place concrete foundation and walls have been poured.

Tunnel boring continues from the South Shaft, heading in the direction of the North Shaft.

The project team wishes everyone Happy Holidays and a Happy New Year.

Friday, December 18, 2009

Did You Know? Way Cool Stats about the TBM



Okay, I admit that these stats are way cool, even for non-engineers.

The tunnel boring machine (TBM) in use to create the New Crystal Springs Bypass Tunnel has 23 disc cutters in the cutterhead and they are each 17 inches in diameter.

It has a torque of 593,920 foot-lbs and an operating thrust of 1,150,000 lbs operating.

It has 5 gantry cars in its trailing gear, 2 muck conveyors and the total length of the shield and trailing gear is 155 feet.

Here is a photo showing part of its 155 foot long length during assembly in September.

TBM Making Progress in Tunnel!

The tunnel boring machine (TBM) at the South Shaft location is making progress creating the New Crystal Springs Bypass Tunnel!

As of this week, the TBM has mined 401 feet so far, and with the starter tunnel distance included, that brings us to 532 feet or 12.4% complete.

Here is a photo from the bottom of the South Shaft.

Friday, December 4, 2009

Happy Holidays from the New Crystal Springs Bypass Tunnel project staff

Happy Holidays from the New Crystal Springs Bypass Tunnel project staff. We appreciate your interest, support and patience during this important project.

We wish you and your families a wonderful holiday season.