Monday, September 30, 2013

New Irvington Tunnel Neighbors compete in the Final Tunnel Hole-Through Challenge at Open House

Last week, neighbors of the New Irvington Tunnel project stopped in for a cup of coffee and to hear the latest updates on tunnel progress at Mission Coffee House in Fremont.  Attendees were able to discuss construction progress, see new project photos, handle some rock samples collected from tunneling, and participate in the final "hole-through" challenge. 

 Residents participate in the Tunnel Hole-Through Challenge

We are still anticipating the exciting moment when the miners will meet underground between the tunnel segment from Vargas East to Alameda West Portal.  The winner will be notified to receive their gift basket of local goodies as soon as the day comes.  Thank you to all who have participated in the New Irvington Tunnel Hole-Through Challenge!  

Our final guesses are shown here:
For more project info, please email mle@sfwater.org or call our 24 hour answer line 866-973-1476.

Sunday, September 22, 2013

One more week to play! New Irvington Tunnel Challenge


Sometime in the next few weeks, two teams of miners will meet hundreds of feet underground. One is excavating the New Irvington Tunnel eastward from the Vargas Shaft near I-680; the other is working its way west from the Alameda West Portal in Sunol Valley.

When will they meet?
Guess correctly and you could win a wonderful prize pack featuring gift certificates to local businesses!

Need a little help?
As of September 14, 2013, our miners have tunneled 5,044 feet east from Vargas and 8,758 feet west from Alameda West. In ideal ground conditions, crews have tunneled an average of 130 feet per week. When ground conditions are poor they excavate less than 20 feet. We have 405 feet left to go to hole-through as of September 14, 2013.

How to Play

The chart squares shown below correspond to a possible date and timeframe when the tunneling teams will meet. Selections already submitted by contestants are indicated by a “star “.
  1. Choose three squares and e-mail your choices to: mle@sfwater.org
  2. If your first choice is available, then you will be assigned that square. If the square is unavailable, then the next available choice is assigned. You will receive an email confirmation with your selection.
  3. Include the date and time you think the hole-through will take place. Squares will be assigned on a first come, first serve. Only one square is allowed per person
  4. Please include your name, phone number and e-mail address so we can contact you if you make the winning selection.
  5. Submissions will be accepted through September 29, 2013.  GOOD LUCK!



New Irvington Tunnel Project Background
The SFPUC is constructing a new 3.5 mile long tunnel to transmit water between the Sunol Valley and Fremont. The New Irvington Tunnel has been excavated from four different tunnel headings. The first two headings met each other in June 2012. This second and final ‘hole-through’ will mark the completion of excavation of the entire 18,660 ft tunnel. Following the hole-through, miners will prepare the tunnel for the installation of 8.5 ft diameter steel pipe, installed in 50-foot sections and welded together inside of the tunnel. This is a major milestone as the final project completion is near!

Tuesday, September 17, 2013

Your Challenge - When will our Tunnels Meet?

Sometime in the next few weeks, two teams of miners will meet hundreds of feet underground. One is excavating the New Irvington Tunnel eastward from the Vargas Shaft near I-680; the other is working its way west from the Alameda West Portal in Sunol Valley.

When will they meet?
Guess correctly and you could win a wonderful prize pack featuring gift certificates to local businesses!

Need a little help?
As of September 14, 2013, our miners have tunneled 5,044 feet east from Vargas and 8,758 feet west from Alameda West. In ideal ground conditions, crews have tunneled an average of 130 feet per week. When ground conditions are poor they excavate less than 20 feet. We have 405 feet left to go to hole-through as of September 14, 2013.


How to Play

The chart squares shown below correspond to a possible date and timeframe when the tunneling teams will meet. Selections already submitted by contestants are indicated by a “star “.
  1. Choose three squares and e-mail your choices to: mle@sfwater.org
  2. If your first choice is available, then you will be assigned that square. If the square is unavailable, then the next available choice is assigned. You will receive an email confirmation with your selection.
  3. Include the date and time you think the hole-through will take place. Squares will be assigned on a first come, first serve. Only one square is allowed per person
  4. Please include your name, phone number and e-mail address so we can contact you if you make the winning selection.
  5. Submissions will be accepted through September 29, 2013.  GOOD LUCK!

New Irvington Tunnel Project Background
The SFPUC is constructing a new 3.5 mile long tunnel to transmit water between the Sunol Valley and Fremont. The New Irvington Tunnel has been excavated from four different tunnel headings. The first two headings met each other in June 2012. This second and final ‘hole-through’ will mark the completion of excavation of the entire 18,660 ft tunnel. Following the hole-through, miners will prepare the tunnel for the installation of 8.5 ft diameter steel pipe, installed in 50-foot sections and welded together inside of the tunnel. This is a major milestone as the final project completion is near!

Tuesday, September 10, 2013

Feeling Steamy at Calaveras Dam

Among many other fascinating geological features present at the Calaveras Dam project site, a geothermal steam vent has recently been exposed during construction. Although typically associated with volcanic activity, steam/gas vents are also frequently found near large active faults, like the Calaveras fault, which is within 1/4 mile of the project site. There is also evidence of past geothermal activity in the vicinity of this vent. As seen in this photograph, there are areas of hydrothermally-altered bedrock (gray sandstone stained yellow) and holes where former vents, now dormant, were once active.

The construction team continues to monitor the temperature and the gaseous emissions of the present feature, and has created a cautionary exclusion area around it, but, as seen in this video, there has been no adverse effect to construction activity. We will keep you posted on our findings!