Where Are We Now? New Irvington Tunnel Update

At the largest work site, Alameda West Portal, workers are maintaining steady progress. They began last week at a distance of 607 feet, but with the help of the robust roadheader and the highly efficient locomotive removing spoils from inside the tunnel, they were able to increase their distance by 48 feet and end the week strongly at 655 feet.



Tunneling began just over a month ago at Irvington Portal off of Mission Blvd. and work is rapidly progressing. On Monday of last week, workers continued from the previous week at a distance of 82 feet. With lots of hard work and the help of the roadheader grinding away, they ended on Friday at 146 feet. That’s an additional 64 feet in just one week!



Just off the 680 freeway lies the Vargas Shaft, where work began in early 2011. Tunneling has stopped for the moment as workers are busy drilling drain holes to discharge excess water from the tunnel, which will allow for easier tunneling. Tunneling will hopefully resume this week after which workers will be headed westward!

New Irvington Tunnel in the News!

In print and on camera, everyone wants to know more about the New Irvington Tunnel. Check out the amazing photos of the past and present day construction and detailed exhibits in June 2011 issue of Tunnels and Tunneling International. READ ARTICLE

Next take a tour with Tunnel Talk and watch their coverage of the Rapid Excavation and Tunneling Conference’s (RETC) up close look at the New Irvington Tunnel. WATCH VIDEO.

Tunneling at Irvington Portal has Started

Update
On June 20, Southland/Tutor Perini JV began tunnel excavation from the Irvington Portal in Fremont. The contractor will advance the tunnel using a road header (a tracked tunnel excavator) and controlled detonation if necessary depending on the rock conditions. Other construction support equipment will load and haul the excavation spoils from the site to a disposal area on Calaveras Road in the Sunol Valley.

Controlled Detonations
If the road header encounters harder than anticipated rock conditions underground, the use of controlled detonations may be necessary. This involves the use of small amounts of explosives to fracture the rock material so that it can be removed by the tunnel machinery. Safety horns would be sounded a set period of time before each event. We will monitor to ensure that controlled detonations comply with all local, state and federal safety, noise, and vibration requirements. Controlled detonations are only allowed to occur Monday through Friday between 7:00 AM and 7:00PM and on Saturday between 8:00 AM and 5:00 PM. No more than two controlled detonations are anticipated per day on the days that controlled detonations are needed. But most of the excavation is anticipated to be successful by the road header alone.

Notification
Due to the nature of tunneling, it is challenging to predict far in advance when controlled detonations would be necessary. The SFPUC will provide residents with advanced e-mail notification of controlled detonations as early as possible (24 hours minimum). To receive e-mail notifications of controlled detonations, please send a message to fzamora@sfwater.org.

Residential Construction Surveys
Many residents exercised their option to have photographic and video surveys of their property prior to construction. These surveys document existing cosmetic and structural cracks for each property and are used as basis for evaluating claims of new damage caused by construction activities. If you have not had a survey conducted please contact the SFPUC as soon as possible, we may conduct surveys until July 6, 2011. Please call 866.973.1476 and reference the New Irvington Tunnel Project or e-mail fzamora@sfwater.org to schedule a photographic and video survey.

Questions?
Please call our 24-Hour Answer Line at 866.973.1476.

NBC Bay Area. Sunol Water Project Trying to Head off Major Quake.

Calaveras Dam Replacement Project Construction Contract Awarded

The construction contract for Calaveras Dam Replacement project was awarded on May 24, 2011 to Dragados, USA/Sukut Construction, Inc./Flatiron West Inc. joint venture for approximately $259 million.

KTVU Video: New Irvington Tunnel Project Underway

Want to take an exclusive look at the New Irvington Tunnel? Check out KTVU Channel 2's sneak peak at the construction taking place to seismically upgrade the aging Hetch Hetchy Water System.

http://www.ktvu.com/video/27877116/index.html

Construction Moves Forward for Improvements at the Sunol Valley Water Treatment Plant

Construction is moving forward for the Sunol Valley Water Treatment Plant Expansion and Treated Water Reservoir Project. As of April 2011, construction for the overall project is 25 percent complete. Recently the contractor, Shimmick Construction Company, Inc., completed the extensive earthwork and soil nail wall required to build the new treated water reservoir, which included the removal of over 400,000 cubic yards of material. This work is part of various improvements that will enable the treatment plant to treat enough water to meet basic customer demands alone for up to 60 days after a major earthquake as well as improve water quality at the plant. All these improvements are expected to be completed in summer 2013.

Workers finish securing the soil nail wall, which will help stabilize the treated water reservoir. Photo courtesy of Robin Scheswohl.

The excavation work for the treated water reservoir included the removal of over 400,000 cubic yards of material. Photo courtesy of Robin Scheswohl.