Friday, June 15, 2018

What's the Big Deal about an Approach Channel?

We are building a new earth and rock fill Calaveras Dam right next to the existing 93 year-old dam (directly downstream of the existing dam as they say in the dam industry.)  As many of our previous blog posts have been tracking, we have been busy building the new dam, foot by foot, from the bottom up like a layer cake. A very large layer cake.

Our Calaveras cake is high enough now to allow us to begin to excavate out the approach channel to the new dam this week.

"What is an approach channel?" you ask. An approach channel is a breaching of an existing dam in order for its adjacent reservoir to come in contact with it. We will remove a portion of the existing dam (500,000 cubic yards of it to be exact) to allow reservoir water to eventually fill in the space between the old dam and the new dam. The old dam will look like a peninsula in the reservoir when the project is done. 

"Why not remove the old dam in its entirety?" We don't have to. Complete removal would be expensive, environmentally difficult, and not necessary to operate the reservoir. 

The start of excavation of the approach channel means that we have reached a high enough elevation with the new dam to safely begin carving out a huge chunk of the existing dam. It's a coming of age for the new dam, if you will. A significant milestone. 

Here is what the approach channel looked like at the beginning of last week.

And, here is what it looks like this week.

The channel will be lined with large rocks called rip rap to protect it from erosion so the channel will be ready when we start to refill the reservoir this fall.

Approach channels may not seem exciting at first glance, but we at the SFPUC are thrilled!

See you around the valley!

Friday, June 8, 2018

Photo Friday at the Bay Division Pipelines

Happy Photo Friday!

We've been neglecting the Bay Division Pipelines in our East Bay Photo Series. So we thought we'd celebrate this Photo Friday with a couple of construction shots - from 1966.

Five Bay Division Pipelines transmit Hetch Hetchy and East Bay supplies through our two Irvington Tunnels to our 2.7 million Bay Area Customers.  Bay Division Pipelines 1,2, and the newest addition - 5 connect to a brand new water tunnel under San Francisco Bay on their way to the Peninsula.

Pipelines 3 and 4 pass through the South Bay overland on their way to the Peninsula. 

As you can tell, these are large pipelines. They are also crucial to our water transmission system.

We can't blame those kids. We think they're pretty cool, too!

See you around the Valley!

Monday, June 4, 2018

SFPUC Project Team Leads National Discussion about Dams and Ecosystems

In early April members of the Fish Passage Facilities project team went to Miami, Florida to present at the 38th United States Society of Dam’s (USSD) Annual Conference on behalf of SFPUC. This year's conferences theme was A Balancing Act: Dams, Levees and Ecosystems. It focused on the importance of environmentally sustainable water projects within diverse and sometimes fragile ecosystems.

Our Fish Passage Facilities team were selected to present their paper called "Fish Passage Facilities at the Alameda Creek Diversion Dam, Final Design and Construction Update."

The Fish Passage Project is located in Sunol.  The goal  project is to provide for safe passage of fish around the Alameda Creek Diversion Dam to support the restoration of Steelhead trout to the Alameda Creek Watershed.  The project is part of the SFPUC's $4.8 billion Water System Improvement Project (WSIP) to repair, and seismically upgrade portion of the Hetch Hetchy Regional Water Sytem. Construction is expected to be completed in fall 2018.

Below is a photo of our fabulous four presenters: Eric Gee, Project Manager, Yen Ng, Engineer and Karl Tingwald, (former AECOM) civil engineer and Dan Wade, Director of Water Infrastructure Capital Projects and Programs.

We want to congratulate the Fish Passage team members for a job well done.

See you around the valley!

Friday, May 25, 2018

Memorial Day 2018

In observance of Memorial Day, our construction teams at the Calaveras Dam Replacement Project, Fish Passage Facilities within the Alameda Creek Watershed (within EBRPD's Sunol Regional Wilderness) and the Sunol Valley Long Term Improvements (Water Temple) will not be working on Monday, May 30th.

Here is a photo of one of our D4 Dozer's working on the dam’s core at the Calaveras Dam Replacement Project.

We hope all of you have a safe and wonderful Memorial Day weekend.

See you around the valley!

Friday, May 18, 2018

Happy Infrastructure Week 2018

The Week of May 14 to May 21st is national Infrastructure Week! This is the week where public agencies across the nation highlight the importance of our nation’s infrastructure, and the need to maintain it.

At the San Francisco Public Utilities Commission, our ratepayers had the foresight more than 10 years ago to allow us to pass the $4.8 billion Water System Improvement Program (WSIP). The program has 87 projects, spanning seven counties, to repair, replace, and seismically upgrade aging portions of the Hetch Hetchy Regional Water System. To date the program is more than 90% complete.

A tremendous amount of work was done in the Sunol Valley to ensure a seismically reliable water supply for our Bay Area customers.  The Calaveras Fault runs right through the Sunol Valley. The Calaveras Dam Replacement Project is the largest WSIP Project in construction, but there have been many others. Here are the highlights:  

Alameda Siphon #4. A high tech pipeline crossing of the Calaveras Fault designed to survive an earthquake. Completed 2013.

New Irvington Tunnel. A new seismically designed tunnel to connect the new Siphon with new pipelines in Fremont. Tunnel brought into service in 2015.

Upgrades to our Sunol Valley Water Treatment Plant to enable the plant to provide minimum demand to all of our 2.7 million customers on its own for up to 60 days. Completed 2015.

A complete new Bay Division Pipeline #5 to connect the New Irvington Tunnel to a new Bay Tunnel and the Peninsula. Completed 2016.

We've been posting videos on Facebook all week to highlight the SFPUC's efforts to upgrade your infrastructure. And at Twitter: #TimetoBuild. See the Facebook posts  here.  

See you around the Valley!

Friday, May 11, 2018

Photo Friday - Lupine at Calaveras Dam

Happy Photo Friday from the Calaveras Dam Replacement Project!

The hillsides in the Sunol Valley are still green this time of year, and wildflowers are blooming, including at the Calaveras Dam Replacement Project.

Robin Scheswohl, our fabulous SFPUC photographer, captured this beautiful photo. You can see the new dam being constructed in the background and blue lupine in the forefront.

Construction of the dam itself is expected to be completed this year, with site restoration to follow.

See you around the Valley!

Friday, April 27, 2018

Fossils from the Calaveras Dam Replacement Project Find their New Home

The San Francisco Public Utilities Commission (SFPUC) has been working since 2011 to build a replacement Calaveras Dam out of seismic concerns for the existing 93-year-old dam in the Sunol Valley.

To make space for the new earth and rock-fill dam, the Calaveras Dam Replacement Project has had to move almost 10 million cubic yards of soil and rock. While moving all this earth, the project team began to find what has been called one of the greatest fossil finds in the Bay Area in decades.

To date more than 1,300 specimens have been discovered. Most them are fossils from an ancient ocean and beach area approximately 15 to 20 million years ago. Water covered much of California back then, and an inland ocean extended to the Central Valley.

Many of the fossils are high-quality specimens that can be used to further research into evolution or global change. (UC Berkeley photos by Sara Yogi)

Amongst the vertebrate fossils are marine mammals, like baleen whales or Mysticetes and toothed whales and dolphins or Odontocete; and Desmostylus, an herbivorous hippo-like marine mammal), seals or sea lions, sharks, and bony fish, such as halibut.  The invertebrates include scallops (some as big as a dinner plates), clams, snails, cockles, mussels, crabs, and barnacles. The team believes it has found a new species of whale among the dozens of whale skulls found.

Researchers have pieced together the jawbone from a 15- to 20 million-year-old whale. 
(UC Berkeley photos by Sara Yogi)

Researchers can tell this area was near to shore because they have also found plant material that washed into the ocean from land, including pine cones, palm trees, leaves, and wood. They can tell that the Bay Area was warmer back in this time, and the ocean teemed with life.

Through an agreement between SFPUC and the University of California Museum of Paleontology (UCMP) the entire collection of fossils will now be housed within the UCMP collections. The fossils represent California’s fossil heritage and as such, belong to all the citizens of California, and will be managed on their behalf by the University of California Museum of Paleontology. 

The UCMP assembled a team to manage this collection, including a Lab Manager – Dr. Cristina Robins, many undergraduate students, two graduate students per semester, and volunteers.

Graduate student Mackenzie Kirchner-Smith uses a brush to spread adhesive over a fossil found during the Calaveras Damn replacement project. (UC Berkeley photos by Sara Yogi)

Dr. Robins and her team painstakingly chip away the rock from the fossilized bone to identify each specimen. It is laborious work. They often find new specimens inside the rock blocks around other specimens. More fascinating fossil discoveries lay ahead for the UCMP team.

Fossils waiting to be released from rock fill the small lab located at UCMP.

And we at the SFPUC know the fossils are in excellent hands.

See the video and read more here:

See you around the Valley!

Friday, April 20, 2018

ENR’s 2017 Top News Maker Award Winner: Susan Hou

Every year, Engineering News-Record (ENR), a construction industry magazine awards 25 people in the United States for their outstanding work in the construction field. To select ENR Newsmakers, ENR’s editors search the magazine’s web and print pages for individuals who had served the “best interests of the construction industry and the public.”(ENR Website). This year, Susan Hou, SFPUC's East Bay Regional Project Manager was chosen to be a recipient of this prestigious award.

Susan Hou

Susan joined the Calaveras Dam Replacement Project in 2011 and become its project manager in 2013. She has guided the team through many challenges. Through her leadership and collaboration, Susan kept the team on track.

Susan Hou with CDRP's Managment Team

Congratulations Susan!

See you around the Valley!

Friday, March 30, 2018

Come Join us at the Wildflower Festival!

The hills are green and the flowers are in bloom in Sunol. This is a perfect opportunity to come out to the East Bay Regional Park District's Wildflower Festival to learn more about the flora and fauna of the region.

When: Sunday, April 8, 2018 from 10 am to 4pm
Where: Sunol Regional Wilderness, 1895 Geary Road, Sunol, CA
Cost: Free admission ($5 parking)

The festival is a fun family day out. Learn about watershed animals, wildflowers, and grasslands. Enjoy the beauties of spring in one of the East Bay Regional Park District’s crown jewels at the Sunol Regional Wilderness. Learn more at

Stop by and visit us at our booth. Get the latest and greatest information on all of our ongoing projects. Flaunt your Alameda Creek Watershed knowledge and win a prize! Fun crafts for the kids.

We hope to see you there!

Friday, March 9, 2018

Sometimes Construction Methods Don't Change

Image courtesy of
(place image here)

The photo below was taken in 1918-- when the first Calaveras Dam was being constructed.  These workers are excavating in the dam's foundation.  They're using using 4-mule carriages(4-horsepower) to do the job. Each power train (4-mule carriages) transport approximately 4 cubic yards per load at a speed of 1 to 2 mph. 

Fast forward a hundred years.  The photo below was taken at the new Calaveras Dam as workers were excavating the new core.  The workers in this photo are doing the same job with a Caterpillar Motor Scraper with a 450 horse power engine capable of carrying 30 cubic yards at a speed of 25 to 30 mph.

Although times have changed, sometimes the methods don't.  

See you around the valley!

Thursday, March 1, 2018

Carpenters Hard at Work

Today’s photos were taken by SFPUC photographer, Robin Scheswohl, inside the construction project to rebuild our Sunol Corporation Yard, which is located near the Sunol Water Temple.

While on site, Robin caught sight of a few of the approximately 11 carpenters who are working to build the structures for the new hub of East Bay water system operations for SFPUC staff. 

Here's a glimpse of their hard day's work.

Carpenter welding steel framing inside one of our buildings.

Here's one of our talented carpenter’s welding a piece of steel.

And, here she's installing the steel framing.

The Corporation Yard will be home to our Water Supply, Treatment East Bay Operations and Natural Resources Personnel. Improvements are expected to be completed by the end of 2018. During construction, the Sunol Water Temple will be closed to the general public.

See you around the valley!

Friday, February 9, 2018

Sunol The Bobcat is Back!

In the late summer of 2016, our team found this cute bobcat kitten alone and abandoned on the embankment of the replacement Calaveras Dam under construction.

Image courtesy of W.E.R.C

Our Environmental Inspector, Bill Stagnaro and Geologist, Carrie Dovzak, arranged for the kitten to be transferred to the Wildlife Education and Rehabilitation Center (W.E.R.C) in Morgan Hill, California. The W.E.R.C Center has a world-renowned bobcat kitten program. This program ensures that single orphans such as Sunol, as she was later named, do not become habituated during their time in care. They help socialize the orphan and reinforce bobcat behavior, such as hunting and stalking techniques.

Sunol was recently released, with the permission from California Dept. of Fish and Wildlife and the Park Rangers.  During her release, she was given plenty of water, prey, and cover to help ensure her long-time survival.

Image courtesy of W.E.R.C

Image courtesy of W.E.R.C

Bobcats, also called lynx rufus, are found throughout the United States. They are nocturnal animals that hunt small rodents. Many people confuse them for mountain lions even though they are much smaller.

We wish Sunol a very happy life in her native home.

See you around the valley!

For more information on the Bobcat rehabilitation program at W.E.R.C go to:

Friday, February 2, 2018

Winter at Calaveras Dam

There is plenty of work happening during this winter season at the Calaveras Dam Replacement Project.  Although our construction team is not working on the dam’s embankment, they're keeping busy with other important construction projects that need to be completed before spring. Here is a glimpse of the work in progress.

Our team is working hard to construct some of the support facilities. Support facilities such as: the stream maintenance vault, the downstream toe electrical building and all of the electrical equipment are needed to operate the outlet works.

V34 Vault

Electrical Panels for Stream Maintenance Vault

Electrical Panel in Downstream Toe Building

Our team continues to prepare the left abutment foundation. Part of this job entails removing a temporary tieback retaining wall. This temporary tieback retaining wall was needed during the construction of the spillway to support an ancient landslide.

Tie Backs

During the past two weeks, our team has been working hard installing the last of our piezometers. For more information on our internal and external instrumentation, reference our November 7, 2017 and December 15, 2017 blog posts.

Drill Rig for Insturmentation


Our crew is working hard to finish these projects before the spring time. As you can see, there is a lot of activity happening in the winter months.

See you around the valley!

Friday, January 19, 2018

A Celebrity at the Alameda Creek Diversion Dam

There was a celebrity in our midst at the SFPUC's Alameda Creek Diversion Dam, the site of the Fish Passage Facilities Project. Field Biologist Chris Pattison spied this California Red-legged frog recently near the construction site and moved it to a safer location.

"Why is this frog famous?" you ask.

Could it be because the California Red-Legged frog (Rana draytonii) is a federally threatened species? 

Or that they are found almost exclusively in California?

Or that they were once a common meal for miners during the Gold Rush?  

Give up?

It has the distinct honor of being the Official Amphibian for the State of California. Read more in this blog post from 2014.

It is heartening to know that these really special frogs are still hopping around the Alameda Creek Watershed.

See you around the Valley!

Friday, January 12, 2018

Photo Friday from January 9, 1913

Happy Photo Friday!

While the East Coast of the U.S. experiences frigid temperatures and some frightening weather event called a 'bomb cyclone', we in the Bay Area, have been experiencing relatively mild temperatures. 

This was not always the case, however. For this Photo Friday we delve back to photos taken almost exactly 105 years ago, on January 9, 1913. 

On that day the crews constructing the first Calaveras Dam found their work site covered in snow. 

The site was so remote back then that the crews lived on site. Here is the watershed keeper's house and another worker's cabin.

Shown here is a barn, corral, and nearby cottage. 

It might be foggy out there today, but at least it isn't snowing!

Happy long weekend and see you around the Valley!

Friday, January 5, 2018

Sunol Valley's Native Residents - California Tiger Salamanders

Photos curtesy of Bill Stagnaro

It has started to rain in the East Bay! And with the first major rain fall of fall and winter appears a native Sunol Valley resident - the California Tiger salamander (Ambystoma californiense). 

These ever smiling amphibians are very elusive and hard to find. They are not really smiling but appear to be because of their wide mouth outlined in yellow. An adult California Tiger salamander can reach 7.5 inches or more in length.  Adults are black or dark grey, with oval to bar-shaped spots ranging in color from white to yellow. Juveniles are dark olive green in color and do not generally have any lighter markings. The best time to spot them is at the beginning of the rainy season.

The California Tiger salamanders found in the Sunol Valley are a federally threatened species. These beautiful amphibians have a complex life cycle that requires them to have different types of habitats. During mating season, they like to live in vernal or stock ponds. The juveniles and adults live in grasslands and oak woodlands, mainly living underground in the burrows made by other animals.  It is not uncommon to find California Tiger salamanders cohabiting with a family of ground squirrels.

During breeding season they will travel a mile or more to a nearby pond to breed. Although they may live as long as 10 years, they may reproduce only once. Females lay eggs singly or in small groups. Its larvae require significantly more time to transform into juvenile adults than other amphibians. Around late spring, salamanders leave the ponds to find burrows.

You most likely will never spot a California Tiger salamander during the hot summer months that’s because they are in estivation. Estivation is basically another word for “summer hibernation.” During this time they enter a dormant state and will not come out of their burrow until late November or the rainy season.

Photo curtesy of

If you’re ever spot a California Tiger salamander in the Sunol Valley,  smile back at it and count yourself lucky to have spotted it.

See you around the Valley!