What’s Going On Next to the Highway 92 Crossing?

Alexis Pope, the sole female diver on the project, 

rigs a water pump for washing out the culvert. 

The divers work on the barge 

as well as underwater.

If you cross the Crystal Springs Reservoir on Highway 92, you’ll pass a construction barge yet no construction is visible. The real action is 60 feet underwater, where divers with the Water System Improvement Program work on a seismic upgrade of the Upper Crystal Springs Dam lower culvert. The culvert has been weakened by past earthquakes where it crosses the San Andreas Fault.

To strengthen and provide flexibility to the 370’ long tunnel, the contractor has placed a 42” wide high density polyethylene pipe (HDPE) inside the 60” wide brick lined tunnel in a process called “sliplining”. Flexible grout and slurry delivered by a materials barge are pumped in-between the old pipe and new slipline to provide additional cushioning against future earthquakes. 

In addition, a vertical portal will be installed outside the area where the culvert crosses the fault as a fail-safe. It will maintain water flow from Upper Crystal Springs to the Lower Crystal Springs Reservoir if a major seismic event damages the lower culvert where it is bisected by the fault. 

Divers wear video cameras, communication lines and lights
on their helmets, and a warm water hose for comfort,
all connected to the barge via lengthy cables. 

Project Schedule

Dredging for vertical portal: December 2013

Expected completion: February 2014

This project, together with all of the other improvements to the regional distribution system, will allow the SFPUC to meet its goal of delivering potable water within 24 hours after a major earthquake.

A crane and temporary buildings are staged 

on the barge to support underwater construction work.

Photos by Robin Scheswohl, SFPUC

For more information on construction diving in the Crystal Springs - San Andreas Reservoir system, please see our article from April 2013.

Warm Winter Wishes

Happy Holidays!

As we look back over 2013 we’d like to say “Thank You” to our neighbors for your cooperation in our work to upgrade the aging Hetch Hetchy Water System. We send you wishes for warmth, happiness and delicious clean water this holiday season and beyond.

Hetch Hetchy Reservoir

All our best,
The Water System Improvement Program, Peninsula region

Behind the Scenes in Front of Lower Crystal Springs Dam

   

Hetch Hetchy Water System improvements are progressing steadily on both sides of the Lower Crystal Springs Dam. In front of the Dam, the new Crystal Springs Pump Station is a hub of construction activity. The pump station moves water from the Crystal Springs Reservoir System to the San Andreas Reservoir with a third more hydraulic capacity than the old pump station, thus allowing SFPUC to advance water to the Harry Tracy Water Treatment Plant faster than before and thereby meeting the SFPUC level of service commitment to provide potable water within 24 hours after a major seismic event.  When the pump station is completed, most key functions can be controlled remotely from Harry Tracy, located eight miles north.

   

While the pump station itself is nearly completed and actively undergoing testing, work continues on water transmission tunnels, pump station infrastructure pipelines, and the emergency release/dissipation structure nearby.

L to R: Lower Crystal Springs Dam, old CS pump station, emergency 
release/dissipation structure under construction, and new pump station.

Work on the emergency release/dissipation structure adjacent to “pool 2” in San Mateo Creek (above) required SFPUC biologists to survey the area and remove endangered steelhead trout before the pool could be temporarily drained. 

Staff Biologist Madeleine Van Der 
Heyden carefully transfers endangered 
steelhead to a bucket for relocation.

Staff Biologist Chris Pattison snorkels to find 
steelhead trout.




Crystal Springs Outlet Tunnel before and during retrofit


Two valves housed deep within the emergency release/dissipation structure minimize turbulent flow into San Mateo Creek during releases from the Lower Crystal Springs Reservoir. 

    

Construction on both sides of the Lower Crystal Springs Reservoir, together with all of the other improvements to the regional distribution system, will allow the SFPUC to deliver potable water within 24 hours following a major earthquake on the San Andreas Fault.

Emergency Preparedness Month

The First 72 Hours
This October, take time to engage in your community, discuss ideas and plans, and prepare for an emergency or natural disaster. The SFPUC’s Emergency Preparedness Month encourages all San Francisco-area residents to become more aware and prepared for the next emergency, which is almost certain to take place in our lifetimes. The first 72 hours after an emergency are often the times when community members come together to help each other out. If we prepare beforehand, we’ll be better off when an emergency occurs.

What can you do?
Meet with your family, neighbors and community organizers to get connected, develop a plan and share resources. Use SF72.org and sfwater.org/BePrepared as starting points. You’ll find tips, guidelines for supplies, a mobile app and   stories from real San Franciscans.

This is our city
SF72.org was developed by San Francisco for San Francisco. Let’s protect each other and our city by using our resources and knowledge to the fullest when an emergency strikes.

Our community members are not the only ones getting prepared. The SFPUC has been improving and renovating our regional water system to ensure a safe and reliable water supply. Although San Francisco will always need to rely on this imported water from the Sierras, we are also developing additional water supplies that can be used in the event that our regional system is disrupted. For example, we are developing local wells in San Francisco to blend high-quality groundwater with our imported water supplies, and we’re producing recycled water for non-drinking purposes to reduce the amount of drinking water currently used in these ways.

Check www.sf72.org or www.sfwater.org/BePrepared for more information. 

  

Temporary Trail Closure 10/21/13

On Monday, Oct. 21^st, Sawyer Camp Trail will be closed all day for Water System-related maintenance.

We are aiming to wrap up work in this area before the rainy season. San Andreas Trail will be open.

Questions? 

Please call us at (866) 973-1476, 24 hours a day, 7 days a week.

Trail Closures October 14th & 17th

On Monday and Thursday, Oct. 14^th and 17^th, Sawyer Camp Trail will be closed for Water System-related maintenance. 

The trail will be closed all day for all 6 miles. San Andreas Trail will be open. 

Questions? 

Please call us at (866) 973-1476, 24 hours a day, 7 days a week

Follow us on Twitter: @SawyerCampTrail

Temporary Trail Closure Wednesday

Sawyer Camp Trail will be closed Wednesday, Oct. 9th for Water System-related maintenance. The work will close all 6 miles of the trail.

San Andreas Trail will remain open. No further closures are scheduled at this time.

Questions? Please call us at (866) 973-1476, 24 hours a day, 7 days a week.