Air Monitoring Program Continues at Calaveras Dam

If you are traveling on Calaveras Road, you may notice what appears like chain link cages along the side of the road. These are our air quality monitoring stations.  These stations have been placed throughout the valley and within the construction boundaries of the Calaveras Dam Replacement Project.  Our teams collect air sampling data throughout the week at the various stations to ensure we are protecting the public and our workers at all times. 

Why are we doing this?

Portions of the approximately 7 million cubic yards of material which is being moved to construct the replacement Calaveras Dam contain rock formations that contain varying levels of Naturally Occurring Asbestos.

Geotechnical explorations in the area of the Calaveras Dam Replacement Project construction revealed that the Sunol Valley contains rock types that are known to contain naturally occurring asbestos and metals.  Serpentinite rock (“California Jade”) is the state rock of California and occurs naturally in at least 44 of California's 58 counties.

The SFPUC has implemented an extensive air monitoring program that is designed to keep dust generation to a minimum while assuring that asbestos-containing dust does not leave the site at levels sufficient to pose unacceptable risks to individuals who may work, recreate, or reside in the vicinity of the site.

For more information about our air quality monitoring and to see the latest air monitoring results, visit our NOA Website by clicking here.  Our results are updated weekly.

Our Staff collecting samples from an air monitoring station

Meet David from our Calaveras Dam Air Monitoring Team
working at one of our air monitoring stations

Update: New Irvington Tunnel Construction Activity at Irvington Portal

Excavation of the New Irvington Tunnel is more than two-thirds complete! The contractor has finished making the last of the necessary connections between the large water pipelines at the Irvington Portal. The contractor will begin ramping down construction activities at a portion of the site. The first step will be the partial demobilization and site restoration on the southern portion of the property.

Starting as early as February 20, 2013, the contractor will begin the process of removing some of the sound barriers at the project site. (See Map Below)

What to Expect
The sound barriers will be removed at the locations depicted in the map. The work involves removal of the panels and digging around the concrete foundation. Workers then remove the foundation and cut or pull the steel beams out. The excavated area would then be backfilled. Noise associated with sound barrier removal will include the operation of heavy equipment, back up alarms and concrete breakup.

Removal Hours
Sound barrier removal can take place Monday through Friday from 7:00 AM to 7:00 PM. We will continue to monitor noise and vibration in this area to ensure full compliance with strict noise and vibration standards set forth in the project’s Environmental Impact Report.

What’s Next?
We are not done at Irvington Portal, yet! Installation and burial of permanent portal facilities and security improvements will continue through 2013 into 2014. Site restoration for the remainder of the project site will commence in 2014.

Questions? 24-Hour Answer Line at 866-973-1476 or email mle@sfwater.org or blauppe@sfwater.org

Areas in yellow highlight sound barriers to be removed,
areas in blue will still remain

 Photo of Sound Barriers



Planting Underway at Restoration Sites in Sunol

The majority of construction work at the Goldfish Pond and San Antonio Creek restoration sites has been completed. Crews at both of these Bioregional Habit Restoration (BHR) project sites in the Alameda Creek Watershed are now focused on the planting efforts.

At the Goldfish Pond Restoration project site, crews are currently planting more than 25 different types of plants, represented by the colored flags seen in these photos.These plants will help create various wetlands at the site. This planting work is expected to be complete in Feburary. We will continue to monitor the success of restoration efforts at this site through the year 2023! 

 

At the San Antonio Creek Restoration site, crews are planting a variety of grasses, shrubs and trees that total 300,000 plants to create both oak savannah and sycamore riparian habitats. All of the plants are expected to be in the ground in December 2013. We will monitor the success of these restoration efforts until 2023 at this site as well.

These projects are part of the SFPUC’s unique approach to mitigation and our environmental commitment that combines the impacts of several different WSIP projects into one suite of projects to maximize our ability to make significant habitat improvements for rare and endangered species.

Calaveras Road Construction Advisory: 1/24/13 - 1/25/13 Truck Traffic

The Calaveras Dam Replacement Project will be expecting additional haul truck traffic on:

January 24 & January 25, 2013  just south of Interstate 680 to the project site approximately 4 miles past Geary Road.

·         Road remains open to the public

·         Haul trucks are expected from 7:00 a.m. to 4:00 p.m.

·         Please drive and bike safely on the narrow portions of Calaveras Road Speed limit is 25 mph in construction zones

                                                                                                                                                                                     

For More Information:

24 hour-Answer Line 866-973-1476

Email us:

mle@sfwater.org or blauppe@sfwater.org

Follow us online at: Sfwater.org/sunolvalley

Another Shut Down for the Books

The New Irvington Tunnel Project has just completed its winter pipeline shutdown work this season.

“What’s the big deal?” you ask. Here’s why.

Our construction team must construct upgrades to this water system while it still provides water to our 2.6 million customers.  We shut down the pipelines in order to cut into them and weld pipeline connections to improve your water system.  We can only do this for short periods of time during winter months when demand for water is low. The timelines within which the contractor can complete their work are very short. The work is very complex and challenging in a very tight area. No pressure!

At the Irvington Portal area in Fremont, the contractor Southland Tutor Perini had two shutdown seasons – last year and this – to complete a complex set of pipeline connections between the existing Irvington Tunnel, the New Irvington Tunnel currently under construction, and the five Bay Division Pipelines. These pipelines can only be shut down one at a time during winter months.

The SFPUC is creating pipeline connections to allow water to be distributed from both tunnels to all five pipelines in a variety of ways.  Work on the final Bay Division Pipeline #4 connection started on November 5, 2012, and the project team recently completed the work.

For our customers this means a water transmission system that will be more flexible from an operational standpoint and better able to withstand a major earthquake.  For our construction team it means a pat on the back for a job well done.

Work being done on the final Bay Division Pipeline #4 Connection

Workers perform welding work on pipeline

For more project info, please email mle@sfwater.org or call our 24 hour answer line at 866-973-1476.

Seashells and Secant Piles

A recent trip to the Sunol Valley by SFPUC photographer Katherine DuTiel produced a photo that, by striking coincidence, looks remarkably like one taken on the Bay Division Pipeline Project on the Peninsula.

Look closely to see which is which!





Shown here is the receiving shaft of the Bay Division Pipeline micro tunnel section on the Peninsula. The project was forced to tunnel under a culturally and environmentally sensitive area at the end of this 9 mile pipeline. The secant wall in the shaft consists of a series of drilled piers filled with concrete. They are arranged concentrically to provide a continuous concrete wall that supports the shaft.



The Sunol Valley area was covered by the Pacific Ocean about 20 million years ago. Life along the old coast was similar to today, with abundant clams, mussels, sea worms and other invertebrate organisms living in the sand. The sandstone formation that represents the old ocean deposits is called the Temblor sandstone, and contains fossils from this old coastline. The photograph shown above is a fossil scallop collected by geologists at the Calaveras Dam Replacement Project.

What do Dams and Space Shuttles have in common?

The Calaveras Dam Replacement Project work site is a busy place on an average day. Machines both large and small are in constant motion, moving soils and materials from one side of the site to dispose of them on the other.

However, this Wednesday around lunchtime was different.  Work paused, for a short time, to celebrate the team’s achievement of another milestone. The team has moved a total of 2 million cubic yards of rock and soils since the project began in August 2011.  As the team enjoyed its well-earned pizza lunch to celebrate, we wondered how much dirt they’d just managed to move.

2 million cubic yards of dirt weighs as much as 1,656 space shuttles. It weighs as much as 1,175 Saturn V Rockets and weighs as much as 18,225 Boeing 747’s.

Here’s another question: Why? Building a dam is similar to painting a house, in that the majority of the work goes into the preparation. The team needs to remove all the loose materials on both sides of the valley and the valley floor so the new dam will be built upon a solid base.  The Calaveras Dam Replacement Project will have to move more than 9 million cubic yards of soils and rock during construction. About 3.5 million cubic yards of the materials will be used in the construction of the new dam, while the remainder will be disposed of onsite.

Two down, only seven million more cubic yards to go! And the crew is geared up, full of pizza, and ready to get going. 

Our Calaveras Dam work crews take a few moments to celebrate the important milestone of excavating
over 2 Million Cubic Yards of materials

As seen almost daily, a scraper moves soil and rock materials excavated at the project site

For more project info, please email mle@sfwater.org or call our 24 hour answer line at 866-973-1476