Happy Infrastructure Week 2018

The Week of May 14 to May 21^st 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!

One huge pipe at Calaveras Dam

As we busily work towards construction of a replacement Calaveras Dam, there are many fundamental issues we have to address. For example, given that the existing Calaveras Dam will be left in place when we are done, how will we be able to transport water out of the reservoir when the new dam is built?

Answer: We are building a large pipe (more than 7 feet in diameter) that will be completely buried in the new dam that connects directly to the outlet structure already in place in the existing dam.

This pipe will transport our drinking water supply from the Calaveras Reservoir to the Sunol Valley Water Treatment Plant and then on to our 2.6 million Bay Area customers when supplies are needed.

To date, our crews have installed 500 feet of the new steel pipe, welded  the joints, and started building the formwork for reinforced concrete encasement  around the entire pipeline to protect it. The pipeline and encasement  has been designed to withstand the force of being buried under 180 feet of earth embankment as well as the force of any seismic activity from the nearby Calaveras Fault. The team plans to connect the new 78 inch pipe to the existing pipes within the existing dam in Fall 2016. 

Seems a shame to put all this work into something that will be completely buried under more than 3.5 million cubic yards of earth and rock. But, thanks to these careful efforts, customers will be able to drink Calaveras Reservoir water, even after an earthquake.

The new pipe is shown here in orange on the layout, connecting to existing pipes in green.  The old pipeline in black is being abandoned to excavate the foundation for the new dam.

Sunol Valley: Getting Prepared

This week we acknowledge the 25^th Anniversary of the Loma Prieta Earthquake. On October 17, 1989 at 5:04 p.m, the magnitude 6.9 Loma Prieta earthquake, also known as the “World Series Quake,” lasted 15 seconds causing an estimated $6-10 billion in property loss in the Bay Area. The anniversary is a reminder to all of us to make efforts to be prepared for the next major earthquake.

Here’s a quick snapshot of what’s been done in the Sunol Valley to better prepare us:

San Antonio Pump Station – Completed

The San Antonio Pump Station is one of the key facilities in the Sunol Valley which pumps Hetch Hetchy water through a transmission pipeline to the San Antonio Reservoir to the Sunol Valley Water Treatment Plant. It serves as a critical seismic upgrade project which provides a reliable water supply to our Bay Area customers after a major earthquake.

Sunol Valley Water Treatment Plant – Completed
If the Hetch Hetchy water supplies become unavailable for any reason, this plant enables us to supply the minimum demand of water to our customers, especially those in the East Bay and South Bay. The plant can now provide 160 million gallons of water per day for up to two months in case of an emergency. Previously, that level of service would run out after only a matter of days.

Alameda Siphon No. 4 – Completed
This project will ensure the water system performs properly, and water can be delivered to customers after an earthquake. The Alameda Siphon No. 4 Project extends approximately 3,000 feet from the Alameda East Portal across both the Calaveras Fault and Alameda Creek to the Alameda West Portal. It consists of a seismically-designed thicker-walled pipe in the fault rupture zone, and a tunnel crossing under Alameda Creek. 

The SFPUC and the Town of Sunol Celebrate the Holidays

Pizza, cider and rock samples! The SFPUC’s Holiday Open House at the Sunol Event Center was the place to be last Thursday night!

Sunol residents mingled with their neighbors and engaged in lively conversations about the history of the valley with SFPUC staff. Guests played with rock samples from the Calaveras Dam, marveled at construction photos of the New Irvington Tunnel and enthusiastically shared their vision for the proposed Alameda Creek Watershed Center.


Residents also had the opportunity to learn about other ongoing projects in the area including: the San Antonio Backup Pipeline; San Antonio Pump Station; Alameda Siphon #4; Sunol Valley Water Treatment Plant; Town of Sunol Fire Suppression System; and the Watershed and Environmental Improvement Program and Bioregional Habitat Restoration Program.


The smell of homemade banana bread and hot apple cider filled the air as guests enjoyed freshly baked artisan pizzas topped with locally grown vegetables from Fred Hemple and Jill Shepard’s Baia Nicchia Organic Farm. Our youngest guests decorated their own ornaments and bookmarks.

Thank you to those who were able to attend our holiday event.

To all of our neighbors in the Sunol Valley and folks we’ve had the pleasure of working with this year, we want to wish everyone a very happy holiday season!

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