Milestone Breakthrough for the New Irvington Tunnel

Roadheader breaks through for final hole-through on October 8th

On October 8, 2013 at precisely 9:00 a.m. two crews of miners from the New Irvington Tunnel project met underground with their roadheader digging away at the last final feet of rock.  Miners celebrated the final hole-through excavation of the 18,660 foot tunnel.  The 3.5 mile New Irvington Tunnel will transmit water between the Sunol Valley and Fremont to our 2.6 million Bay Area customers. Work is still not quite done yet, our miners will prepare the new tunnel for installation of 8.5 ft diameter steel pipe, installed in 50-foot sections and welded together inside of the tunnel.  This will be followed by the placement of cellular concrete between the steel pipe and tunnel wall to complete the project in mid-2015. 

 

Hole-Through Challenge Winner: Priya Iyer
With that, we also would like to congratulate our Hole-Through Challenge contestant.... Priya Iyer! Priya selected the winning time and date of the hole-through and will be receiving our prize package.  Congratulations to Priya!

Our hardworking New Irvington Tunnel crew

                                      Tunnel Superintendents Jim Mulkey and Jack Bowling from 

                                      Southland Contracting share a handshake after the hole-through.

New Irvington Tunnel Project Staff celebrates Hole-Through

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!

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!

KGO Bay Area News - Fremont Tunnel Work Reaches Major Milestone

A Road Header Rendezvous

9:46 AM June 12, 2012

Inside of a 13-foot diameter hole carved into the Alameda foothills, crews waited yesterday morning staring at an imposing rock wall.  A moment later, as if it came from within the mountain, a spinning titanium studded knuckle broke through. It moved back and forth and up and down until the wall disappeared.  What happened next was a long time coming: two crews, dressed in identical hard hats, headlamps and goggles stepped through the new hole, shook hands and then shared a laugh.

Video Captured with Permissible Camera

After 13 months of digging the New Irvington Tunnel from four separate tunnel headings, miners from two of the headings met up with each other underground today. Called a ‘hole-through’ in tunneling terminology, the road header teams from the Irvington Portal in Fremont and the Vargas Shaft 4,500 feet away shook hands somewhere under the mountainside and formally completed this section of tunnel excavation.

The road header holes-through the rock face

Miners at the Irvington Portal watch the road header hole-through from the Vargas Heading 

Miners celebrate their achievement

Photographs by R. Scheswohl ©2012 SFPUC, All Rights Reserved

The tunnel is excavated using conventional mining methods including a road header (a tracked tunneling machine) and, in sections of hard rock, controlled detonations.  In May 2011, a 55-ton road header was lowered down the 115-foot Vargas Shaft and began to grind its way west.  A month later, miners at the Irvington Portal in Fremont began tunneling east and set the two crews on a collision course.  

Following today’s hole-through, miners will prepare the tunnel for the installation of 102-inch diameter steel pipe.  The pipe, manufactured in California, is installed in 50-foot sections and welded together inside of the tunnel.   The much longer 14,400-foot Alameda West-Vargas tunnel segment is currently being excavated and is expected to hole through in fall 2013.  Construction of the entire project is scheduled for completion in fall 2014.

New Irvington Tunnel Challenge Continues!

Tunneling excavation continues east from Mission Boulevard with the use of controlled detonation at a rate of approximately 12 feet per day. A road header travels west from I-680 at a rate of approximately 15 feet per day. When will the two meet?

Your challenge is to figure out the day and time you think the tunneling workers will meet. Guess correctly and you could win a prize pack featuring gift certificates to local business and other goodies! The chart has squares corresponding to a date and timeframe in June or July, when the rendezvous could happen. Selections submitted by contestants are indicated by a star.

Information to Help You Choose

In June or July, miners excavating the new tunnel from the Irvington Portal in Fremont will meet miners tunneling west from the Vargas Shaft. When it happens this hole-through will mark the completion of the Irvington-Vargas tunnel segment.

The tunnel segment between Irvington Portal and Vargas Shaft is 4,500 feet long. As of May 7th, miners have tunneled 1,747 feet east from Irvington and 1,955 feet west from Vargas. Ground conditions dictate excavation. In ideal ground conditions, crews have tunneled up to 98 feet in a day. When ground conditions are poor they excavate less than 20 feet. Miners do not tunnel on Sundays.

How to Enter

1) Choose your top three squares and e-mail your choices to: fzamora@sfwater.org

2) Include the date and time you think the hole-through will take place. Squares will be assigned first come, first serve. Only one square is allowed per person

3) If the first choice is available then the square is assigned to that person. If the square is unavailable then the next available choice is assigned.

4) Submissions will be accepted until May 31. Please include your name, address, phone number and e-mail so we can contact you if you're successful!

Good luck!

Road Header Rendezvous Challenge

A road header travels east from Mission Boulevard at rate of 45 feet per day. A second road header travels west from I-680 at a rate of 35 feet per day. When will the two road headers meet?

At some point, we’ve all scratched our heads and tried to figure out a math problem like that. Here at the SFPUC we won’t ask you to solve word problems. Instead, we invite you to be part of our Road Header Rendezvous Challenge.

In June, miners excavating the new tunnel from the Irvington Portal in Fremont will meet miners tunneling west from the Vargas Shaft. When it happens this hole-through will mark the completion of the Irvington-Vargas tunnel segment.

The chart above has 101 squares each corresponding to a date and timeframe in June when the rendezvous could happen. Your challenge is to figure out the day and time combination. Guess correctly and you could win a prize pack featuring gift certificates to local business and other goodies.

How to Enter
Choose your top three squares and e-mail your choices to fzamora@sfwater.org. Include the date and time you think the hole-through will take place. Squares will be assigned first come, first serve. Only one square is allowed per person.

For example, someone could submit the following:

1. June 19 between 6:01 AM and 12:00 PM
2. June 5 between 6:01 PM and 12:00 AM 
3. June 28 between 12:01 AM and 6:00 AM 

If the first choice is available then the square is assigned to that person. If the square is unavailable then the next available choice is assigned.

Submissions will be accepted until May 31. Please include your name, address, phone number and e-mail so we can contact you if you're successful!

Information to Help You Choose
The tunnel segment between Irvington Portal and Vargas Shaft is 4,500 feet long. As of April 24, miners have tunneled 1,657 feet east from Irvington and 1,810 feet west from Vargas. Ground conditions dictate excavation. In ideal ground conditions, crews have tunneled up to 98 feet in a day. When ground conditions are poor they excavate less than 20 feet. In the last month miners averaged 38 feet per day. Miners do not tunnel on Sundays.

We’ll update the tunnel’s progress every week at www.sfwater.org/nit. Good luck!