Grinding Forward

Tunnel crews are grinding their way forward on the New Irvington Tunnel Project. Miners excavate in four directions using road headers (tracked tunneling machines) and controlled detonations when necessary to dig out the 18,600-foot (3.5 mile) tunnel.

Over 2000 feet of tunnel has been excavated with approximately 16,600 feet remaining. Last Friday tunnel crews dug out a new daily record of 50 feet for the project. As the crews become more familiar with and how to deal with the variable ground conditions, the mining production has steadily improved each week. Tunnel excavation is estimated for completion in mid-2013 with project completion in mid-2014. Check out www.sfwater.org/nit for weekly updates of tunnel progress.

The New Irvington Tunnel will provide a seismically-designed connection between water supplies from the Sierra Nevada Mountains and the Alameda Watershed to Bay Area water distribution systems. The new tunnel will lay parallel to the existing tunnel between the Sunol Valley south of Highway I-680 and Fremont, California.

Calaveras Dam Replacement Project Update

Road Closure Update
We have received permission from Alameda County to temporarily close Calaveras Road south of Geary to the Alameda/ Santa Clara County Line for two separate periods
- The first two-month road closure, initially planned for fall 2011 is now planned for early 2012.
- The second road closure is expected in late 2012/early 2013 for a period of 18 months.
- Calaveras Road will remain open on weekends, but will be closed Monday-Friday during these periods.
- Access to the Sunol Wilderness will remain open
from the north at all times and from both the north and south on weekends.
- Emergency vehicles will have access to the road at all times.
- The roads will be swept clean of debris prior to weekend openings.

Calaveras Dam – Controlled Detonation
The contractor will be using controlled detonation to produce the hard rock required for construction of the dam. To excavate the foundation of the dam, we may encounter rock that is too hard for our machinery, in which case we may also use controlled detonation. You may hear the detonation or feel minor vibrations from the activity. If you would like to receive an email notification beforehand, please contact Maria Le at mle@sfwater.org.

If you have any additional questions or concerns, call our 24-hour answer line at (866) 973-1476.

Share the Road: One Road, Many Users

Construction activity is now underway for the Calaveras Dam Replacement Project. Safety is our #1 priority.

Please be cautious of the large trucks and increased traffic along Calaveras Road, specifically south of I-680. Due to the narrow road conditions, please remember to ride and drive safely through the blind curves. The speed limit is 25 mph in construction zones.

We understand this is a popular route for bicycling enthusiasts and we hope we can all share the road safely. Please note that Calaveras Road will be closed for 2 periods. The first closure has been postponed until early 2012. Please check back here for updated road closure info.

Feel free to contact us at any time at 24 hour answer line at (866) 973-1476, or mle@sfwater.org. Thank you for sharing the road!

Then and Now

The existing Irvington Tunnel was built in the early 20th century and can no longer be taken out of service for repairs or maintenance without impacting the water supply to customers. The New Irvington Tunnel is designed to provide a seismically-strengthened or reinforced connection between water supplies from the Alameda Watershed to Bay Area customers.



The Alameda West Portal in August of 1929. Miners excavated the existing Irvington Tunnel between 1928 and 1931 primarily using drill and blast techniques.


The Alameda West Portal in April of 2011. Miners are using road headers (conventional tunneling machines) and limited controlled detonations to excavate the tunnel. The project is expected to be completed by mid-2014.

NIT: Extended Construction Hours

Update
Beginning on October 3, 2011 through May 9, 2012, the contractor is authorized to conduct construction activities 24-hours per day 7-days per week at the Irvington Portal in Fremont, as may be necessary to complete time critical work for the New Irvington Tunnel connections to the existing Bay Division Pipelines.

What Can I Expect?
On weekdays from 7AM to 7PM and weekends from 8AM to 5PM construction activities will focus on the crane placement of new pipe and be similar to what is currently being experienced. Outside of those hours the contractor will work on connecting and welding of pipe at the new tunnel. The operation of construction equipment (loaders, excavators and cranes) is necessary to complete this work. Worker trips to and from the site at shift changes will also take place. Tunneling is not allowed after 7PM on weekdays and 5PM on weekends. An effort will be made to complete all the work during daylight hours, and minimize work during the evenings and nights.

Will Work Take Place During the Holidays?
The contractor does not currently plan to work on Thanksgiving, Christmas or New Years Day. However, they have the ability to work on those days in order to complete their work within the extended work hour period. Residents will receive advanced notice if it becomes necessary to work on those days.

Why are Extended Hours Necessary?
This work can only be completed during the winter seasons when water demand is at its lowest. It is imperative for the contractor to finish his work and re-establish full capacity water service before water demand increases in the warmer months of Spring. In order to do this, the existing waterlines are cut out for the tunnel connections only one at a time, leaving other waterlines in service. The waterlines are drained and cut out and new connection waterlines are installed. Water service will not be impacted because there is redundant capacity in the pipelines during the winter seasons.

Questions?
Please call our 24-Hour Answer Line at 866.973.1476 or visit sfwater.org/nit if you have questions or comments.

Let the Digging Begin: New Calaveras Dam Breaks Ground

On September 16th, General Manager Ed Harrington joined local and state officials to break ground on the construction of the Calaveras Dam Replacement Project. The 4-year, $416 Million dam is one of only several major dams built in California in 30 years. Alameda County Supervisor Nadia Lockyer and Sharon Tapia from the California Department of Water Resources, Division of Safety of Dams were on hand along with neighbors and project supporters. The contractor cut the first notch into the existing dam since it was originally built in 1925.




The Calaveras Dam Replacement Project will replace the existing dam with a 220-feet high new seismically-designed earth and rock-fill dam that will be constructed right next to the existing one. The Calaveras Dam Replacement Project is part of the SFPUC’s $4.6 billion Water System Improvement Program (WSIP) to repair, replace, and seismically upgrade the aging pipelines, tunnels and reservoirs in the Hetch Hetchy Regional Water System.

Dedicated to Safety: Tunnel Rescue Team

Excavating a tunnel is dangerous business. Skilled miners put their lives at risk every time they go underground, in conditions that may expose them to grounds that cave in, flammable gasses and groundwater that might pour in and flood the tunnel. Protecting the safety of our workers is the top priority of the San Francisco Public Utilities Commission (SFPUC) and Southland Tutor Perini Joint Venture (STP). Should the unthinkable happen and miners need a rescue the Tunnel Rescue Team is ready at a moment’s notice.


Tunnel Rescue Team members are highly trained specialized tunnelers who put themselves directly in harm’s way to come to the aid of their colleagues. They are trained to enter a tunnel under hazardous conditions that would prohibit most people from entering to provide first aid, extract personnel, or put out fires.


At the New Irvington Tunnel (NIT), the Tunnel Rescue Team is a 13-member team on-call 24 hours-a-day 7 days-a-week. A back up tunnel rescue team from the Caldecott Tunnel Project is also available. First responders from CalFire and the Alameda County and Fremont Fire Departments support the Tunnel Rescue Team above ground.


The Tunnel Rescue Team practices and drills regularly to ensure their skills are ready when needed. We sincerely hope that their services will never be needed. But if they are, the NIT team invests time each day to be sure we are ready to protect the lives of the workers who are helping to ensure a reliable water supply for all of us.