From an Engineer’s Perspective

Annie Li gives us an exclusive, inside look at an engineer’s life at the SFPUC! As a senior civil engineer, Annie worked on the Alameda Siphon No. 4 Project in the Sunol Valley. The project entailed seismically-upgrading the pipeline, which extends approximately 3,000 feet from the Alameda East Portal across both the Calaveras Fault and Alameda Creek to the Alameda West Portal. Check out the video here to learn more about the project, some of SFPUC’s facilities and the road to becoming an engineer. 

Calaveras Dam Replacement Project Team Reaches Milestone

The Calaveras Dam Replacement Team has been working hard since early April, scraping away at existing earthen materials to excavate for the dam foundation.  This week, the team has reached 1 million cubic yards of materials excavated, which would cover an entire football field 60 stories high.  A total of 7 million cubic yards of excavation is required for the entire project.  Approximately 3.5 million cubic yards will go into the construction of the new dam.

Our team has been operating scrapers daily, excavating approximately 20,000 cubic yards per day.  The scrapers operate with hydraulics using a blade which then scrapes materials into a drop can, carrying an average of 28 cubic yards per trip.  These materials are then moved to disposal areas within the project site. 

The Calaveras Dam Replacement Project Team Celebrates the first

Million Cubic Yards of Earth Moved on July 13th

Construction Manager Jordan Sukut representing the general contractor Dragados USA/Flatiron/Sukut Construction congratulates the field team on the milestone

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

Keeping Thirst at Bay

How do you keep thirst at bay while implementing major improvements to several key water systems? In this month’s issue of CE News, you can learn just how the Sunol Valley regional projects team does it! Click here to learn about how the teams are working to seismically upgrade 70-year-old water infrastructure, how they successfully built a new water lifeline across the Calaveras Fault and how they handle water shutdowns during construction. 

Who’s Who Underground?

For almost two years we’ve discussed the ins and outs of tunneling. What is a road header? Do we still use canaries? Why do we have lasers? These are some of the questions that we’ve tried to answer since construction began nearly 2 years ago.

Here’s our next question: Who’s Who Underground?

For the answer to that question, we turn to the International Tunneling and Underground Space Association (ITA). A collaboration of 19 counties, ITA recently featured a New Irvington Tunnel inspector and geologist Rebecca Fusee in a web documentary promoting engineering careers in tunneling. The documentary features young underground engineering professionals working on complex projects around the world.     
Rebecca is featured at the 3:16 mark of the video. 

For this critical component of the Hetch Hetchy Water System, a tunnel inspector and geologist coordinates with miners throughout excavation. Rebecca and her colleagues document each step of excavation to ensure the contractor is working to design specifications. They also map the underground geology and analyze ground conditions. Over the course of construction, we’ll take a closer look at the men and women working in the new tunnel.

Protecting Migratory Birds at Calaveras Dam

Over the last 100 years, the state’s migratory bird populations have declined due to loss of habitat.  Here at the Calaveras Dam Replacement Project, our teams make great strides to protect the population of our migratory birds.

Nesting season generally falls between February 15^th to August 15^th for most species. Our Environmental team performs focused surveys for active nests prior to the start of construction activity.  The staff survey for active nests of migratory birds and protected raptors, such as the Bald Eagle. 

Bird nesting deterrents such as reflective signs are also placed near or on construction equipment to prevent birds from nesting near work.  When active nests are found, our teams immediately place disturbance-free buffers around the active nest until the young have fledged successfully.  This year, a Bald Eagle pair successfully produced eagle chicks away from the Calaveras Dam project site at the nearby PG&E tower. 

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

Our Bald Eagle nest at the PG&E tower

Some bird species, such as the Black Phoebe shown above, nest on construction equipment. The equipment was monitored and remained unused until the nestlings fledged. 

Photos courtesy of Bill Stagnaro & Cullen Wilkerson, Calaveras Dam Project Environmental Team

What's Next?

What do the San Francisco Giants and the New Irvington Tunnel have in common?  Last week they both achieved significant milestones!

For the Giants, Matt Cain pitched the first perfect game in team history.  Afterwards his teammates rushed onto the field and celebrated his incredible accomplishment.  For the new tunnel, two teams of miners completed a major tunnel section deep underground.  After the hole-through, miners shook hands somewhere under the mountainside to celebrate 13 months of grueling and hazardous work.

So what’s next? For Matt Cain it was an appearance on David Letterman and win against the Los Angeles Angels.  For the miners it’s more challenging work underground.

At the Irvington Portal miners will install a 102-inch diameter steel pipe that will eventually carry drinking water from the Hetch Hetchy system to 2.6 million Bay Area customers.  The pipe, manufactured in California, is installed in 50-foot sections and welded together inside of the tunnel.   Pipeline installation is expected to take three months. 

Towards the end of this year, the final shutdown (24/7 period) period will take place to install the last connection from the Bay Division Pipelines to the new tunnel.  After the winter shutdown, the remaining major construction items are the installation of above ground portal facilities and security measures and site restoration. 

The much longer 14,400-foot Alameda West-Vargas tunnel segment is currently being excavated and is expected to hole through in fall 2013.  After that 102-inch diameter steel pipe will also be installed and welded together inside of the tunnel.  

Habitat Restoration Begins in the Sunol Valley

The San Francisco Public Utilities Commission (SFPUC) is currently implementing projects as part of the Bioregional Habitat Restoration (BHR), formally known as the Habitat Reserve Program. This will provide high-quality habitat compensation for endangered species and will mitigate for construction impacts related to the Water System Improvement Program (WSIP). This is a unique approach to mitigation for WSIP construction project impacts and is combined into one suite of projects. This pooling of resources maximizes our ability to make significant habitat improvements for rare and endangered species.

Construction is now underway on two projects in the Alameda Watershed for the BHR. Starting today, there will be an increased level of construction activity as well as additional construction traffic within these project areas, so please plan accordingly.

Work hours for both projects are Monday to Friday, 7 a.m. to 5 p.m.

Goldfish Pond Restoration
This project will work to enhance the existing Goldfish Pond, rebuild the embankments, plant over 10 acres for the various wetlands and create five acres of riparian habitat. This project is located east of I-680 in the areas encompassed by Calaveras, Felter and Marsh Roads.

The existing Goldfish Pond being restored.

San Antonio Creek Restoration:
This project will restore and reconfigure a 1.8-mile reach of San Antonio Creek and a ½-mile of the nearby Indian Creek. The restoration will also include installation of a new bridge to establish a creek crossing, installation of multiple grade control structures to create habitat, improvement of the stream bank stabilization with planting, and establish over 80 acres of oak savannah and riparian habitat. This project is located east of I-680, off Highway 84 to the Livermore exit at Vallecitos Road. 

Overhead view of a portion of the San Antonio Creek restoration area.

The BHR includes the development of compensation sites to preserve, enhance, restore or create approximately 1,800 acres of tidal marsh, vernal pools, sycamore and oak riparian woodland, oak woodland and savannah, and serpentine and annual grasslands. It also includes the design, environmental permitting, construction, construction management, maintenance and performance monitoring during a three-year plant establishment period and up to 10 years of performance monitoring.

For more information, please visit the project webpage.