South San Francisco, CA  August 24, 2013

Concern remains strong for this inferno that now has spread to include 125,620 acres and is only 5% contained has destroyed only 1 structure while 4,500 more are threatened. Thankfully only 1 injury has been reported and we have 2,672 personnel working this fire. Please continue to keep those in harms way in your thoughts and prayers, and to the wild land firefighters, please remain safe.

Because San Francisco and San Mateo County residents depend on Hetch Hetchy for water, the reservoir  is being closely monitored for water quality. In addition, the hydroelectric plant that provides energy for San Francisco City facilities and transportation, is also closely monitored.


Rim Fire Updates

August 23, 2013

Hetch Hetchy Regional Water System Continues to Deliver High-Quality Water to Bay Area
Water Quality and Water Supply Remain Unaffected by “Rim Fire” in Tuolumne County

SAN FRANCISCO, CA –Today, officials from the San Francisco Public Utilities Commission (SFPUC) reinforced that the “Rim Fire” in Tuolumne County has not stopped normal water deliveries or impacted water quality from Hetch Hetchy Reservoir. The Hetch Hetchy Regional Water system continues to deliver high-quality water to 2.6 million water customers in San Francisco and throughout the Bay Area.

The “Rim Fire” in Tuolumne County is now approximately 105,000 acres and is approaching Hetch Hetchy Reservoir. The fire is projected to have little or no effect on water infrastructure like O’Shaughnessy Dam because these assets are made of concrete and steel. In addition, water transmission tunnels and pipelines in the area are located safely below ground. As of today, the Hetch Hetchy Regional Water System is still delivering 275 million gallons of water per day to Bay Area residents and businesses across four counties.

Officials have also seen no impact from the Rim Fire on water quality from Hetch Hetchy. All water quality instrumentation confirms that turbidity – a measurement of particles in the water, are well within normal operating parameters. The turbidity of the Reservoir is roughly 0.2 NTU (NTU – standard of turbidity measurement) at present, which is a typical, normal measurement for this time of year. Turbidity will need to trend significantly upwards before the SFPUC makes changes in water supply and delivery. 5.0 NTU or higher is the threshold that mandates changes in water supply and transmission.

The SFPUC has developed contingency plans and the necessary infrastructure to continue to supply all of its customers with water for several months even without Hetch Hetchy Reservoir. Over the past ten years, the SFPUC’s $4.6B Water System Improvement Program has upgraded critical infrastructure and made reliability improvements in order to maintain normal operations, system reliability and water quality during an event just like the “Rim Fire.” Some of these upgrades include:

Physical interconnections with other municipal water agencies like the East Bay Municipal Utility District and Santa Clara Valley Water District to share water resources; and, New and upgraded treatment plants to maintain water quality during and after emergency events.

While water operations continue unaffected, the SFPUC has been unable to generate and transmit clean, greenhouse gas-free hydroelectric power from two of its three main powerhouses, Kirkwood and Holm. Both powerhouses and their transmission lines have been within the fire zone. Moccasin Powerhouse is still generating and transmitting power; any power shortfall will be addressed with other resources or market purchases of power. The San Francisco Public Utilities Commission is the sole provider of greenhouse gas-free power to all of the Cities’ municipal facilities, which include MUNI, SFO, SFGH, City Hall, libraries, the Port, police stations, fire stations and more.

For more information, please visit the web link below for up-to-date information about the Rim Fire and potential impacts on our water and power system: http://www.sfwater.org/RimFire.

Contact: Tyrone Jue (415) 290-0163; Alison Kastama (415) 518-8576; or Charles Sheehan (415) 260-9846

Fact Sheet/Questions & Answers about the Rim Fire and potential impacts on the Hetch Hetchy Water and Power System

Water Quality and Delivery

Q: How is the Rim Fire impacting the quality of Hetch Hetchy water?

A: Water quality is not currently impacted by the Rim Fire.

We are monitoring water quality every minute of each day to ensure its quality and safety.

Currently our Hetch Hetchy water is measuring 0.2 NTU (Nephelometric Turbidity Units), which is within the normal water quality range. Turbidity is a measure of particles in the water.  A turbidity level of 5 NTU or higher is considered a water quality issue and requires changes to water transmission.



Q: Is the Rim Fire impacting water delivery to the Bay Area?

A: The Rim Fire is not interrupting water delivery and our water system is operating as normal.

Eighty-five percent of San Francisco’s water comes from Hetch Hetchy Reservoir.


Hydroelectric Power Delivery

Q: Is the Rim Fire impacting hydroelectric power delivery to San Francisco?

A: Since Monday, 8/19, two hydroelectric powerhouses, Holm and Kirkwood, are not in use due to the Rim Fire.

Moccasin Powerhouse is still generating hydroelectric power. San Francisco is making up the difference in power generation by accessing power in an existing power bank and purchasing power on the open market.

The Hetch Hetchy Power System delivers 100% greenhouse gas-free hydroelectric power to all of San Francisco’s municipal facilities, services and customers, which include San Francisco International Airport, San Francisco General Hospital, Police, Fire, MUNI, retail City tenants, residences and businesses in the Hunters Point Shipyard, Treasure Island and more.

Contingency Plans

Q: Does the SFPUC have a contingency plan in place in case water delivery is interrupted by the Rim Fire?

A: We have a large supply of water stored locally, in Bay Area reservoirs such as San Antonio and Crystal Springs, if needed.

Thanks to our $4.6 billion Water System Improvement Program (WSIP), we have critical water interties with East Bay Municipal Utilities District (EBMUD) and Santa Clara Valley Water District (SCVWD), to deliver water between water systems during emergencies.

10 years ago this critical infrastructure was not available. These regional interties strengthen the reliability of our water systems in the Bay Area.



Update #10

Release for Saturday, August 24, 2013/Time: 6:00 AM From InciWeb

Incident Statics

Acres Burned: 125,620 Structures Threatened: 4,500

Containment: 5% Structures Destroyed: 23

Fire Start Date: August 17, 2013 Injuries: 1

Fire Cause: Under Investigation Total Personnel: 2,672

Cost to date: $7.8 Million


Fire Update

Fire crews continue to work toward increasing containment of the Rim Fire. A major effort focused is underway to hold the fire east of the North Fork of the Tuolumne River. Fire crews have strengthened fire lines that are holding above the community of Pine Mountain Lake. Additional efforts are focused on the eastern edge of the fire in Yosemite National Park to minimize impacts to our national treasure.

Direct attack is being used in some areas of the fire and more will be utilized as firefighters gain safe access. In other areas of the Fire where extremely steep, rugged and inaccessible terrain exist, fire crews are using a tactic called indirect attack which creates control lines away from the fires active edge. Air resources, including several helicopters and air tankers, are being utilized to slow the forward progress of the fire.


Forest Closure

The Stanislaus National Forest has issued an area closure for the entire Groveland Ranger District and for the Mi-Wok Ranger District east of Highway 108. Additional details are available from the Groveland Ranger District, 209-962-7825.

Road Closures

Highway 120 remains closed to all inbound and outbound Yosemite National Park traffic. Also closed are Ferretti Road and Highway 120 to Pine Mountain Drive and Ferretti Road, Smith Station at Highway 120, Cherry Lake at Highway 120, and Evergreen Road.


An evacuation advisory has been issued for Tuolumne City and the area east of Highway 108 to Mi-Wok Village. Advisories have also been issued for the community of Pine Mountain Lake and communities along Ferretti Road from Highway 120 to Pine Mountain Road.

Highway 120 at the Yosemite National Park boundary west to Smith Station Road has been evacuated. An evacuation order has been issued for the area north of Ferretti Road to Elderberry Road.

An evacuation center is at the Mother Lode Fairgrounds in Sonora.

0 0 votes
Article Rating
Notify of

This site uses Akismet to reduce spam. Learn how your comment data is processed.

Inline Feedbacks
View all comments