Water System Improvement Program Sunol Valley

Calaveras Dam Completes Major Work on New Intake Structure

2013-05-15T14:22:00.000-07:00

Our contractor recently completed the final concrete pour for the new intake structure, which is a key component of the Calaveras Dam Replacement Project. This tower is the connection point for the water pipelines that draw water from the reservoir, before it is treated at the Sunol Valley Water Treatment Plant and then sent on to our 2.6 million customers.

The contractor used 1,400 yards of concrete to build the new intake structure. That is the equivalent to the weight of more than 12 cable cars! At 214 feet tall, the structure is almost as tall as the height of the new Calaveras Dam (220-feet-tall). It took our crews more than 29,000 hours to construct the tower.

Crews still need to finish the exterior work on the structure, which will replicate the architectural style of the original tower that was built in 1925. The final external touches are expected to be finished in a few years’ time.

For more project information, contact us at our 24 hour answer line at (866) 973-1476 or email mle@sfwater.org

Original Intake Structure built in 1925

New Intake Structure in progress today

The Calaveras Dam team gathered to celebrate this milestone at the site

What are We Building along Calaveras Road?

2013-05-09T15:06:00.000-07:00

Those who frequently travel on Calaveras Road in the Sunol Valley will likely notice increased activity along the west side of Calaveras Road, south of Interstate 680 (I-680). It is, in fact, the latest Water System Improvement Program Project to begin construction in the Sunol Valley - the San Antonio Backup Pipeline Project. Construction officially began in April, and the contractor, Ranger Pipelines Inc., has begun mobilization activities.

What are we building?

Approximately 1.3 miles of 5 ½ foot diameter pipeline
New chemical storage, feed, and equipment facilities
A new cut-off wall around one of the quarry pits located just south of I-680.
The contractor will also complete upgrades to the water delivery pipeline that serves the Town of Sunol.

What to Expect

Trucks entering and exiting the project driveway site, along Calaveras Road approximately 1/3 of a mile south of I-680 along Calaveras Road.
Intermittent delays are possible during construction on Calaveras Road.
Please proceed with caution when travelling through construction zones.
Additional construction activity on the west side of Calaveras Road.
All construction activities will occur on SFPUC-owned property.

Project Location Map

Alignment for San Antonio Backup Pipeline is in red.

Work Hours

Monday – Friday: 7:00 a.m. to 5:00 p.m.
No planned work on weekends or holidays.

Why are we building this?

Two-way traffic is better, at least in the case of the San Francisco Public Utilities Commission’s (SFPUC) San Antonio Pipeline. The existing San Antonio Pipeline acts as a water transmission pathway in the Sunol Valley. This pipeline allows us to discharge Hetch Hetchy water to San Antonio Reservoir for storage and send reservoir water to the Sunol Valley Water Treatment Plant for treatment before distribution to customers. The problem is that there is currently only one pipeline, so water can only move in one direction at a time.

When complete in 2015, the San Antonio Backup Pipeline will enable the SFPUC to discharge Hetch Hetchy water to a nearby quarry pit during emergency events while at the same transporting San Antonio Reservoir Water to the Treatment Plant at the same time. This adds operational flexibility to the system and minimizes the risk of service disruption to 2.6 million customers.

See you around the Sunol Valley!

Construction Work Starts This Week for Bridge Replacement Project inside Sunol Ohlone Regional Wilderness Park

2013-05-01T09:47:00.000-07:00

What:
The SFPUC is constructing a new bridge to replace the existing unreliable Geary Road Bridge with a new concrete and steel bridge. The new bridge will protect Alameda Creek at this location by eliminating the need for vehicles to drive through Alameda Creek at the low-water crossing. The area will be restored after construction.

Where:
The project area is located inside the Sunol Ohlone Regional Wilderness Park, just south of Leyden Flats before it connects to McCorkle Trail and Camp Ohlone Road, where it crosses Alameda Creek. (See map below).

When: May 1, 2013 through December 31, 2013

What to Expect:
• The area will be closed to the public during construction, Monday through Friday, for safety reasons.
• Park users should use the Canyon View Trail footbridge to cross Alameda Creek. Please pay attention to posted trail closure signs!
• The area will be open to park users on Saturdays, Sundays and holidays. Please proceed with caution.

Work hours:
• Monday – Friday, 7:00 a.m. to 5:00 p.m.
• No work on weekends or holidays

For additional questions or concerns, call our 24 hour toll-free line at (866) 973-1476 or visit www.sfwater.org/sunolvalley.

Fascinating Fossil Finds at Calaveras Dam

2013-04-26T15:25:00.001-07:00

Every day, our scrapers dig soils and earthen materials to make room to build the replacement Calaveras Dam. We have special staff who monitor high sensitivity areas during construction searching for paleontological and cultural resources, which are protected by federal and state laws. Construction crews also attend environmental training about the identification and protection of paleontological and cultural resources. Calaveras Dam project teams have discovered fascinating finds within our construction site.

What are Paleontological Resources?

Paleontological resources include: remains of prehistoric/extinct plants and animals, petrified wood, fossil leaves, fossil remains of vertebrate and invertebrate organisms, fossil tracks and track ways, and plant fossils, typically of Pleistocene Epoch (> 12,000 years ago) or greater age.

What have we found?

Fossilized plants such as wood, leaves, and a pine cone have been salvaged from the site. Invertebrates uncovered include: scallops, clams, snails, barnacles and worms. We have also found shark teeth that are still being analyzed but may be related to a great white shark although much larger (Think “Jaws” and then some).

Our most fascinating finds are linked to prehistoric marine mammal(s). This includes an intact portion of a backbone of a whale. These finds are still being analyzed by experts.

Why?

Most of the fossils have been found in the 20 million year old marine sandstone called the Temblor Formation. The Sunol Valley area was below sea level in the Pacific Ocean about 20 million years ago and has since been uplifted along with the rest of the Coast Ranges. Life along the old coast was similar to today, with abundant clams, mussels, sea worms and other invertebrate organisms living in the sand. But the fossils also document significant differences from today’s relatives and provide important information about the details of evolution and environments of the plants and animals represented by the fossils. We continue to work to preserve and protect these neat findings every day.

Fossils & Shark Teeth discovered at the Calaveras Dam Replacement Project Site

Tweet Us Your Emergency Preparedness Tips!

2013-04-17T12:46:00.001-07:00

April 18 Marks the 107th Anniversary of the Great 1906 Earthquake

The April 18, 1906 earthquake ranks as one of the most significant earthquakes of all time. Beginning at 5:12 a.m., with the epicenter located near San Francisco, the shocks were felt as far north as Oregon and as far south as Los Angeles.

As the earthquake anniversary looms, it presents the opportunity to begin a dialogue with your family and community about emergency preparedness in your home or workplace.

This April, we are providing you an incentive to become better prepared as it relates to water. We want you to share a photo of your water-related emergency preparedness tips. Tweet us @WSIPInTheNews or email us at wsip@sfwater.org now until April 30, and let us know what you're doing to be a local water hero by demonstrating (via photo) or sharing your own tips.

Bay Area residents, social media influencers and city agencies who participate will receive a pen and certificate.

We will retweet your tips and publicly tweet you this certificate. All partnering city departments, Twitter fans and residents will receive this certificate and pen by tweeting us your tip or showing how your city, home or office is a local hero.

New Irvington Tunnel Team Presents at CA-NV AWWA

2013-04-17T11:41:00.001-07:00

Three New Irvington Tunnel project team members recently presented at the American Water Works Association (AWWA) spring CA-NV section conference. They delivered a dynamic presentation on the project’s integrated approach to working with 33 residential well users in the area where excavation would be taking place for the new tunnel. The presentation focused on the development and implementation of the Groundwater Management Plan (GMP) as well as the need for the GMP, extensive public outreach that was conducted prior to construction, how it is being implemented during construction, and some of the lessons learned by the team along the way.

NIT Team Members David Tsztoo (Project Manager), Betsy Lauppe Rhodes (Public Outreach), Bruce Abelli-Amen (Groundwater Consultant), and special guest “Mikey” at the conference.

Alameda Creek Bridge Crossing - Then and Now

2013-04-12T14:31:00.000-07:00

While poking around our archives, we stumbled upon some fun photos. Enjoy!

The Bridge Crossing Alameda Creek in 1953.

The new bridge crossing Alameda Creek constructed by the New Irvington Tunnel Team,

shown here in 2011.

Be A Local Water Hero This April!

2013-04-03T15:55:00.001-07:00

In the event of an earthquake, will you have enough drinking water?

The 107th anniversary of the devastating 1906 earthquake is coming up on Thursday, April 18th.

This April, the San Francisco Public Utilities Commission (SFPUC) encourages all Bay Area residents and business leaders to take the time to discuss plans, supplies and ideas with your family and community to ready your home or office for an emergency or catastrophic event.

Be a Local Hero Contest!

This April, we want to know your tips for emergency preparedness and any precautions you and your family or office have taken to be prepared for an earthquake or natural disaster.

Tweet us @WSIPInTheNews between April 8 and 12, and let us know what you're doing to be a local water hero by demonstrating (via photo) or sharing your own tips. Participants will receive a pen and certificate.

We'll retweet some of your tips during the week of April 15, but are encouraging your participation all month long. All cities and residents are eligible for a certificate by tweeting us your tip or showing how your city, home or office is a local hero.

View Our Short Informational Videos on Emergency Preparedness As It Relates To Water:

Keep a 3-day water supply just in case

View this video to learn more.

If your supply runs out, you can treat your tap water

View this video to learn more.

Locate the water shutoff valve to your building or residence before an emergency

View this video to learn more.

For more information and to view our videos, visit sfwater.org/BePrepared or www.sf72.org.

First Day of Spring at Calaveras Dam

2013-03-21T11:10:00.000-07:00

John Rocca, our Field Operations Manager for the Calaveras Dam Replacement Project, stands on the second bench of the existing Calaveras Dam. Behind John is the where the replacement dam is currently being constructed with targeted completion at the end of 2017.

The left side of the photo shows the stilling basin cut, part of the left abutment of the dam where we are excavating and reinforcing the slope. Shown on the right center of the photo, this hill is referred to as the right abutment where excavations are largely complete. Crews are working on treating the foundation of the future dam.

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

Photo courtesy of Robin Scheswohl, SFPUC Photographer

Local Cavers and the New Irvington Tunnel

2013-03-06T12:09:00.000-08:00

They kindly attended one of our meetings, and we, in turn, attended their’ s. We were delighted to meet members of the National Speleological Society’s San Francisco Bay Chapter (SFBC) at one of our quarterly coffees in Fremont a while back. Much to our surprise, they saw our New Irvington Tunnel (NIT) blog and became interested in the project. They invited us to speak at one of their future meetings about our man-made ‘cave’. Last week Project Manager David Tsztoo and Geologist Rebecca Fusee made a presentation at the SFBC general meeting and ‘rocked out’ as it were by talking about the NIT Project and the complex geology it passes through.

The members of the SFBC Grotto sure know a thing or two about cave exploration, geology, conservation and organizing caving trips with fellow cavers. It was a great experience for our team to have the opportunity to share knowledge about tunneling with this group. Beautiful photos and rock samples were shown of the geologic features from the tunnel excavation, consisting of primarily sandstone, siltstone, shale, and chert ranging from Miocene to Cretaceous age (dated at 5 to 144 million years old). Action photos of our road header equipment used in tunneling were featured during the presentation. We look forward to more talks about rocks with the SFBC!

To learn more about the National Speleological Society San Francisco Bay Chapter, visit their website at www.sfbcgrotto.org

For more information on the New Irvington Tunnel Project, subscribe to our blog, or call our 24 hour answer line at 866-973-1476 or email mle@sfwater.org

New Irvington Tunnel Project Geologist Rebecca Fusee

shares some rock samples from the tunnel with attendees

L to R: John Tinsley, Tom Mathey, NIT Project Geologist Rebecca Fusee, NIT Project Manager David Tsztoo, Alan Chern, Matt Bowers

Preparation Work Starting this Week for the Geary Road Bridge Replacement Project

2013-02-25T12:30:00.000-08:00

The existing Geary Road Bridge that will be replaced.

Working closely with the East Bay Regional Park District, the SFPUC will replace the existing unreliable wooden Geary Road Bridge with a new concrete and steel bridge. This will eliminate the need for vehicles driving through Alameda Creek at the low-water crossing. Construction work will be underway this spring to replace the existing bridge with a new one located in the Sunol Regional Wilderness area in the Alameda Watershed. Once complete in December 2013, the new bridge will be able to accommodate all new truck and pedestrian traffic in order to protect the health of Alameda Creek at this location.

Crews will begin preparing the site this week, which will include installing wildlife exclusion fencing and removing some trees. Some trees that will be removed at this location will be transported and utilized at another SFPUC habitat improvement project site within the Alameda Watershed. Other trees will be used to provide erosion control and stabilization within this project area.

What To Expect:

A small crew of up to 10 workers and several pieces of equipment will be working at this location for up to three weeks.
Regular work hours are Monday through Friday: 7 a.m. to 5 p.m. There will be no work conducted on weekends.
Construction vehicles will off-haul the trees in trucks using the main park road, so park users may experience additional truck traffic.
The bridge will remain open during this time, but park users should exercise caution at the work location and may experience some delays during this time.
Park users should stay outside of fencing and other barriers at this work location.

Air Monitoring Program Continues at Calaveras Dam

2013-02-21T13:35:00.000-08:00

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

2013-02-15T13:27:00.000-08:00

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

2013-02-05T11:10:00.000-08:00

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

2013-01-23T11:41:00.003-08:00

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

Another Shut Down for the Books

2013-01-18T13:57:00.001-08:00

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

2013-01-16T14:18:00.001-08:00

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?

2013-01-09T14:45:00.002-08:00

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

Welcome 2013

2013-01-08T10:30:00.000-08:00

As we turn the page on 2012, we are unfortunately also saying good-bye to a key member of our Sunol Regional Communications Team. Francis Zamora, who has worked with the New Irvington Tunnel Project for over three years, is leaving the New Irvington Tunnel Team to take another position.

Francis (at left below) has been instrumental in the creation and implementation of the Groundwater Management Program process during construction. He also has helped create our Sunol Valley Blog, posting interesting stories, photos, and videos. Only Francis could incorporate references to Star Wars in a blog about tunneling! He also has created memorable public events, presentations, and informational materials in support of the New Irvington Tunnel Project.

Maria Le, who has been working with the Calaveras Dam Replacement Project Team and frequently coordinated with Francis, will be taking over his duties on the New Irvington Tunnel Project in addition to her great work with the Calaveras Team.

Some things will not be changing, however.
As of January 7, 2013, here is the current point of contact list for the Sunol Region:

Maria Le               New Irvington Tunnel
                            Calaveras Dam Replacement Project

(925) 493-4535
(925) 232-4059
mle@sfwater.org

Emily Powell         Sunol Valley Water Treatment Plant

                            Bioregional Habitat Reserve Program

                            San Antonio Backup Pipeline

                            Town of Sunol Projects, including: Fire System
                            Upgrade and the Watershed  Center
(415) 934-3905
epowell@sfwater.org

Betsy L. Rhodes   Oversight on all of the projects above
(415) 554-3240
blauppe@sfwater.org

As always, if you should require assistance at any time, you are welcome to contact our 24-hour answer line, and someone will be able to help you. 866-973-1476.

If you are a Groundwater Management Plan Property owner, you are encouraged to contact Maria with any of your groundwater needs, as you would have contacted Francis. Bill Scott is still available to assist you, as are the remainder of the New Irvington Tunnel Team.

While we are sad to see Francis go, we are excited for him as he embarks on his future endeavors. We wish him the best of luck!

We wish you and yours a very Happy New Year, and we look forward to working with you in 2013.

Calaveras Critters on the Move!

2012-12-26T14:39:00.001-08:00

If the television show Unlikely Animal Friends were to film an episode at the Calaveras Dam Replacement Project, they would have no trouble identifying symbiotic animal relationships all over the Southern Alameda Creek Watershed. Our personal favorites are ground squirrels and the threatened California Tiger Salamander.

Tiger Salamanders live underground in the burrows of other animals, quite often the burrows of ground squirrels. When the rains come to the watershed, the California Tiger Salamanders leave their burrows and make a beeline for a nearby pond where they can meet a mate and lay eggs.

Problem is, there is a large dam construction project in the way. Our biologists placed tubs at strategic locations around the site. As they walk the perimeter of the project on a daily basis, they take the captured salamanders and relocate them to pre-designated places offsite.

They often make sure to stick the Tiger Salamanders into ground squirrel burrows that are stable. The ground squirrels do not seem to mind their amphibious neighbors, and provide the added benefit of digging out the tunnel should it collapse. Otherwise the salamanders would be trapped by cave-ins and might perish. Who knew?

Photo courtesy of Pete Trenum, Elkhorn Slough

For more project info, contact us at our 24 hour answer line at (866) 973-1476 or email mle@sfwater.org

Calaveras Dam hosts Delegation from one of the Largest Dams in the World

2012-12-11T11:08:00.000-08:00

On November 30^th, the Calaveras Dam Replacement Project team was honored to host a high level delegation from the Three Gorges Corporation from China. Along with representatives from the United States Geological Survey (USGS), seven members of the Three Gorges Corporation visited the Calaveras Dam Replacement Project for a site tour.

The Three Gorges Dam and Calaveras Dam – both the existing and the new on under construction – are very different. Three Gorges is a concrete dam that is one of the biggest hydropower-complex projects in the world. Located on the Yangtze River in China, the Three Gorges complex sits on granite bedrock, which provides favorable topographical and geological conditions for dam construction. Three Gorges Dam stands 594 feet tall, 7,661 feet wide, and has the capacity to hold 31,900,000 acre feet of water or over 10 trillion gallons of water.

Calaveras Dam, both existing and the new one, on the other hand, are earth and rock fill. When constructed in 1925, Calaveras Dam was the largest earth and rock fill dam in the world. The foundation of both dams is a unique geologic mixture of Franciscan mélange and Temblor Sandstone. In comparison, the replacement Calaveras Dam will be 220 feet high, 1,210 feet wide, and will hold 96,850 acre feet or 31 billion gallons of water.

Despite the differences in the dams, the two teams found a great deal in common to discuss. The teams shared their respective knowledge about seismic reliability, fishery passage improvements, and overall dam safety. Calaveras Dam was one of many stops in the United States for the delegation. We wish them well on the rest of their journey.

Three Gorges Corporation Executive Vice President Mr. Fan Qixiang
and San Francisco Public Utilities Commission Regional Project Manager Dan Wade

The Three Gorges Corporation Delegation, members of USGS,
and the Calaveras Dam Replacement Team at the crest of the dam

For more project info, contact us at our 24 hour answer line at (866) 973-1476 or email mle@sfwater.org

Calaveras Dam Replacement Project - Winter Update

2012-12-10T14:34:00.000-08:00

Project Update

In mid- June of 2012, during excavation of the large hill known as “Observation Hill” on the left side of the valley (if you are looking downstream, standing with your back to the reservoir), the Contractor encountered unexpected geologic conditions that could contribute to the instability of the left abutment and spillway area as designed. These features were not visible at the ground surface, and were not apparent during the extensive pre-construction geotechnical investigations. Therefore, the excavation cut slope in “Observation Hill” has been re-designed to “lay back” the slope to a flatter slope in order to produce a final slope that will be stable during construction and over the entire life of the new dam.

What this Means

1) Additional Materials to Move - Approximately 3 million cubic yards of additional material that was not originally anticipated now needs to be excavated and moved to disposal sites around the reservoir. We are working with the environmental regulatory agencies to secure disposal sites for these materials within the designated construction areas. No additional materials will be hauled off site on public roads.

2) Extended Construction Schedule - Because of the additional time needed to excavate these additional materials, we anticipate a 25 month delay in the project, which would put the completion of construction activities at the end of 2017.

3) Impact to Project Cost, not to WSIP Overall Cost – Based on preliminary projections, the cost of the project will increase by approximately $133 million. These additional costs are offset by savings recorded on other projects and favorable bond financing so the overall Water System Improvement Program (WSIP) is still forecasted to be completed within the currently approved budget of $4.6 billion.

4) Calaveras Road Shutdown Delayed - The second scheduled closure of Calaveras Road will be postponed until 2014, at the earliest. The duration of the closure remains 18 months, Monday through Friday only, but the specific dates will be determined when the contractor completes re-sequencing of the construction schedule. We will notify you in advance of the closure period. Join our road closure notification mailing list by emailing: mle@sfwater.org or calling our 24 hour answer hotline at (866) 973-1476.

Environmental Review

We are currently working with the regulatory agencies to amend the permits for these changes. The San Francisco Planning Department will distribute an Addendum to the Final Environmental Impact Report in mid-December 2012. To obtain a copy of the Addendum, please visit www.sf-planning.org, or contact: Chris Kern, San Francisco Planning Department at (415) 575‐9037 or email at chris.kern@sfgov.org.

Project Background

The San Francisco Public Utilities Commission, owner and operator of the Hetch Hetchy Regional Water System, is building a new dam to replace the existing Calaveras Dam in the Sunol Valley. Calaveras Reservoir, impounded by the Calaveras Dam, is our system’s largest drinking water reservoir in the local Bay Area. When full it provides more than half of our Bay Area storage capacity for 2.6 million customers. The existing earth fill dam is 87 years old and is located within 1,500 feet of the Calaveras earthquake fault. In 2001 we lowered water levels in the reservoir to less than 40 percent of normal operating capacity in response to seismic concerns. The Calaveras Dam Replacement Project is the largest project of the $4.6 billion Water System Improvement Program (WSIP) to repair, replace, and seismically upgrade key components of the Hetch Hetchy Regional Water System.

Work Completed to date

Construction began in August 2011 to build a new earth and rock fill dam adjacent to the existing dam. Since then, the Contractor has moved nearly two million cubic yards of earth and rock materials to make room for the new dam. Crews have prepared disposal sites, constructed a soldier pile tie-back wall to stabilize a landslide in the right abutment (the right side of the valley as you face downstream from the dam, away from the reservoir), and began injecting cement grout deep into the joints in the rock of the dam’s foundation. The team has excavated to the new dam’s foundation and has started to build the new dam. In addition, we have begun construction of connecting outlets from the reservoir, and successfully completed the first 2-month closure of Calaveras Road in spring 2012. However, there is still a great deal of work that lies ahead, with the project only 26% percent complete as of November 2012.

For more project info, contact us at our 24 hour answer line at (866) 973-1476 or email mle@sfwater.org

Filling the Void

2012-12-07T09:24:00.000-08:00

Last week, crews digging the New Irvington Tunnel excavated an astounding 92 feet in just 3 days. This feat was all the more surprising given that the tunnel was passing through a fault zone where miners excavating the original Irvington Tunnel encountered an enormous amount of groundwater pouring into the tunnel. So much so that it was dangerous for the workers. What was different this time around? Grout.

Crews knew they had entered this zone when they probed 100 feet ahead of their tunnel face and found large amounts of groundwater. Before crews could do any mining forward, they had to inject 66,000 pounds of grout (think liquid cement) into the rock ahead of them to fill cracks and voids in the earth. That’s enough to fill up the water tank pictured below! Grouting fills these voids and keeps groundwater out of the tunnel. It keeps our miners safe and allows tunneling to continue.

Grout is taken by rail to tunnel heading and mixed inside of the tunnel. In November alone, approximately 423,000 lbs. of cement was injected into rock fractures, filling cracks ranging up to 1.5 inches in width.

As of December 4, 2012, over 13,100 feet has been mined. With 5,500 feet to go we expect tunnel expect tunnel excavation to be complete by mid-2014. For those that remember our Road Header Rendezvous Challenge we’ll have another one next year to celebrate NIT’s final hole-through!

Successful Team Work Sees Sunol Plant through Technical Conversion

2012-12-06T08:10:00.000-08:00

Recently, the project team at Sunol Valley Water Treatment Plant successfully completed one of the most technically challenging shutdowns of the Water System Improvement Program (WSIP). In order to upgrade the technical monitoring and control systems for the treatment plant, the entire operating system, that monitors and controls the water flow as it relates to plant operations, was taken off line for two-weeks. This shutdown meant that operators at one of the two treatment plants in our regional system were without the ability to monitor the instruments and processes throughout the plant to treat water as usual. This shutdown also required the team to thoroughly inspect all the critical elements of the plant’s treatment process to ensure they could run manually without the controls system to deliver water to customers, if necessary.

One of the unique aspects of WSIP construction is that all projects must be completed without any water service interruption to our 2.6 million customers. More than 120 system shutdowns must be performed to accommodate WSIP construction.

Since the original treatment plant was constructed in 1964, many of the instrumentation and control systems had reached their maximum data capacity. As new facilities are being constructed and others upgraded, there was no room to incorporate new communication and control signals from the new facilities into the existing controls system. To remedy this overload, the existing data on Programmable Logic Controllers (PLCs) were “split” into separate PLCs to create the needed space and capacity. PLCs are like mini industrial computers that help the operators run the treatment plant. During this “split”, new programming codes for this data were loaded and tested.

Crews worked overtime to ensure the pipe work was completed on time, so it did not delay the treatment plant system coming back on line. In fact, the team successfully completed this shutdown in 12 days, two days ahead of the scheduled 14-day shutdown. This critical shutdown required a detailed System Outage Request (SOR) plan prior to the shutdown identifying contingency options, man-power requirements, material requirements, and detailed work activity schedules to help ensure this critical shutdown was completed without impacts to the water system.

Simultaneous with this technical shutdown, the contractor had to complete several large diameter pipe tie-ins at the plant (shown above).

“Completing this technical work in a tight time frame was not an easy feat, but the team was up for the challenge,” said Paul Gambon, System Operations Manager of the Water Supply and Treatment Division. “The complex nature of this shutdown required close coordination, extensive planning beforehand and excellent communication among numerous project team members and the operations staff,” Gambon explained.

Team members from the following groups were involved with the coordination of this shutdown and contributed to its success: Construction Management team; Shutdown Coordination team; Water Supply and Treatment Division; Water Quality Division; SVWTP Operations team; City SCADA group; City IT/Communications group; Shimmick Construction Company Inc. and Transdyn Incorporated.

As of November 2012, the overall Sunol Valley Water Treatment Plant Expansion and Treated Water Reservoir project is 90 percent complete. The project is expected to be complete by June 2013.

Reminder: NIT Project Open House Tomorrow

2012-12-05T10:26:00.001-08:00

REMINDER

Please Join Us for Coffee at the

New Irvington Tunnel

Project Open House

Thursday December 6, 2012

4:00 PM to 6:00 PM

Mission Coffee

151 Washington Blvd

Fremont, CA

Please stop by and check in on the progress of the new tunnel. Our project team is available to answer your questions and listen to your comments.

Project Update
Over 13,100 feet (out of 18,660) has been tunneled to date. Workers completed the installation of 102-inch diameter steel pipe at the Irvington Portal that will eventually carry drinking water from the Hetch Hetchy system to 2.6 million Bay Area customers.

Installation of the waterline connection to the new tunnel at Irvington Portal near Mission Boulevard continues. We expect the connection fully installed by January 11, 2013.

The New Year will also begin the countdown to the completion of tunneling. Excavation is scheduled for completion mid-2013. The steel pipe liner will go into the last sections of the tunnel by the Fall of 2013.

We look forward to seeing you at the open house!

Please call 866-973-1476 or email fzamora@sfwater.org for

more information. You can also visit www.sfwater.org/nit or