Calaveras Critters: California Tiger Salamanders on the Move

Prior to and during construction, the Calaveras Dam Replacement Project implements measures to avoid and minimize impacts to wildlife located in the Alameda Creek Watershed. The California tiger salamander (Ambystoma californiense) is an amphibian native to Northern California growing up to 8 inches long. California tiger salamanders migrate at night from upland habitats to aquatic breeding sites during the first major rainfall events of fall and early winter.


Our Environmental team has taken proactive steps to protect and relocate the California tiger salamander species. Wildlife exclusion fencing is strategically located along the boundaries of the construction work limits to deter wildlife from entering. Also, water moistened buckets are placed in trenches between silt fences to catch the critters, which are later moved. As of today, 72 California tiger salamanders have been trapped and relocated to safer habitats away from project construction. During construction biological monitors are present during initial vegetation clearing and grading to relocate any wildlife.



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

Photos courtesy of Bill Stagnaro, Environmental Inspector & Biologist

Calaveras Dam Rebuilds Intake Shaft

About four months after construction began, we have witnessed a transformation of the original intake shaft and platform. In September 2011, this area served as the reception area for the official Groundbreaking Ceremony for the Calaveras Dam Replacement Project.


The new intake shaft will be built adjacent to the existing intake shaft with a depth of 150 feet. The soil nail wall is currently being constructed to support the soil surrounding the future intake shaft. The architectural design of the new intake tower will replicate the design of the original tower built in 1925. Tunnels will be constructed to connect the existing water lines to the new intake shaft. The gravity fed system will send water from the Calaveras reservoir to the Sunol Valley Treatment Plant, eventually becoming our drinking water.


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

Not your ordinary Holiday Mixing

Here at Calaveras Dam, we are not mixing your typical holiday cookie dough. For 24 hours a day and 5 days a week, our project teams have been mixing soils for site stabilization. This process is necessary to stabilize the foundation of our disposal area for excavated materials in order to construct the dam.

Deep Soil Mixing is a soil treatment where soil is blended with cement and existing materials. In deep soil mixing, powerful augers are used to mix slurry, thereby stabilizing it for construction purposes. Below are photos of our work, day and night.




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

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!

Sunol Region Holiday Open House

Drop into the SFPUC’s Sunol Region Holiday Open House for a celebration of the holiday season and the coming New Year! Come meet representatives from all of our projects in Sunol Valley. They look forward to chatting with you about all the work we are doing.

Light refreshments and activities for kids will be provided.

Thursday December 1, 2011
6:00 p.m. to 8:00 p.m.
Sunol Event Center
11684 Main Street

Ready for Rains

It’s been wet out there, lately. As the Calaveras Dam Replacement Project begins construction, the team is ready for winter rains. The contractors must be prepared to treat storm water runoff to protect the local creeks. Large areas of exposed ground created as part of construction have the potential to erode soils and impact the water quality downstream. The project has installed a treatment system to protect the local creeks. The treatment consists of removing any silts and clays that may be eroded from exposed excavation surfaces. The contractor has installed an active treatment system that consists of retention ponds and sand filters to clean turbid waters prior to discharging back to the Calaveras Reservoir. The treatment system is designed to manage a flow up to 2,400 gallons per minute, equivalent to approximately 57 bath tubs filled with water.


The treatment system is prepared to operate around-the-clock for the duration of the four year project. We currently anticipate treating approximately 270 million gallons water. As the project prepares to move over 7 million cubic yards of earth over the next four years, the treatment system and other erosion control features will help maintain the water quality in the Alameda Watershed.


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

New Irvington Tunnel: A Year in Construction

The New Irvington Tunnel Project celebrated its first year of construction this past September. When complete the new tunnel will provide a seismically-designed connection between water supplies from the Sierra Nevada Mountains and the Alameda Watershed to Bay Area water distribution systems. Take a look at the important work taking place above and below ground:



Year One by Numbers:

1 Tunnel Shaft: At 115-feet deep and 41-feet diameter, the Vargas Shaft is the starting point for two of the tunnel headings.

2 Tunnel Portals: Carved into hillsides between Sunol and Fremont the Alameda West and Irvington Portals are access and exit points for the new tunnel.

3 Road Headers: Weighing in at a combined 127 tons these mechanical tunneling machines are grinding their way through 3.5 miles of rock.

76 Secant Piles: Drilled and poured 115-feet into the ground this interlocking circle of piles form the support for the Vargas Shaft.

3057 Feet to Date: Miners have excavated this total from 4 tunnel headings.