firefighting

Agencies choose plan to fight fires after quake

by Thomas K. Pendergast

 

A new plan to expand the emergency water system for firefighting after a major

earthquake seems to be gaining support among San Francisco city officials,

but questions remain about options yet to be explored.

 

AWSSHearing

Numerous representatives of the SFPUC and SFFD attended the SF Board of
Supervisors’ hearing on Feb. 7 about protecting the west side from fire, including
the head of the SFPUC, Harlan Kelly (center, first row) and Fire Chief
Joanne Hayes-White (second row, right). Photo: Paul Kozakiewicz

 

After the 1906 earthquake and subsequent fire – which killed an estimated 3,000 people,

many of them probably incinerated because of 300 broken water mains and 23,000 \

breaks on service connections in the domestic water supply which shut off water for the

ensuing conflagration – the City built the Auxiliary Water Supply System (AWSS),

a separate high-pressure water system composed of pipelines and pumps designed to

withstand a major temblor.

 

At the time, most of the City was on the east side of the peninsula, so the original system

was only built out as far west as 12th Avenue in the Richmond District, and eventually it

was built out to 19th Avenue in the Sunset District.

 

AWSS-NEW-1-18-83 copy

The SF Public Utilities Commission has decided to pursue detailed construction
plans (Option 12) for an emergency firefighting plan that utilizes the Sunset
Reservoir as a source of post-earthquake fire-fighting water. Source: SFMTA

 

In the decades that followed, the City expanded westward but the AWSS system did not

follow, leaving about 15 neighborhoods vulnerable to a devastating firestorm, including

the Outer Richmond and Sunset districts, along with Bayview Heights, Crocker Amazon,

Excelsior, Ingleside, Little Hollywood, Mission Terrace, Outer Mission, Sea Cliff,

Stonestown and Sunnyside neighborhoods.

 

After responsibility for the AWSS was transferred from the SF Fire Department to the

SF Public Utilities Commission (SFPUC) by Mayor Gavin Newsom in 2010 to address a

citywide budget deficit, the commission came up with a “flexible hose” system consisting

of 12” hoses being dumped from flatbed trucks and manned by Neighborhood

Emergency Response Team (NERT) volunteers, a plan which the fire department

eventually deemed unworkable.

 

The commission did explore the idea of fully expanding the AWSS to completely cover

the western and southern areas of the City, but balked at its estimated $600 million cost

to complete.

 

In January, the SFPUC announced its latest proposal, consisting of 12 “options” for

expanding the emergency water system to the west side, and to complement

the 30 new water cisterns that have been installed throughout the western and

southern parts of the City.

 

Of those, seven options propose a limited expansion of the AWSS using its current

supply sources of water tanks located at Twin Peaks, Jones Street and Ashbury

Heights. Experts, however, determined that a full expansion of the AWSS based

on only those sources would not supply the gravity-fed system with enough water

at high pressure to be reliable in the western avenues, so another source, the

Sunset Reservoir, was proposed to provide a supply of fire-fighting water.

 

Should the fresh water supply run out for any reason, the AWSS system already

has two seawater pump stations available to use the Pacific Ocean as a source, but

both of those are located on the east side of the city, and thus are limited in the water

pressure they can supply for the western and southern neighborhoods.

 

The remaining options now proposed include a “co-benefits” pipeline that uses

a main transmission line that carries fresh water from the Sunset Reservoir, which

can be used to supplement the City’s lower-pressure domestic water supply, and

stronger, more earthquake-resistant pipes. This plan depends on a series of automated,

mechanized valves working flawlessly to cut the pipeline off from the domestic water

supply immediately after a major earthquake because regular water pipes will likely be

broken and unable to deliver an adequate supply for firefighting.

 

A pump station at Lake Merced is also under consideration as a second source of

water for the co-benefits plan.

 

Conspicuously absent from any options, however, is an expanded AWSS system of

pipelines coming from the Sunset Reservoir, but without the “co-benefits” pipeline

involved at all. Such and AWSS line would not depend on the motorized valves serving

the potable “co-benefits” water pipeline, and thus would be completely independent of

the domestic water supply, but would boost the water pressure for firefighting on the

west side.

 

Also missing are any plans for a seawater pump on the west side drawing water from the

Pacific Ocean.

 

With an estimated cost of $109 million, the favored plan, Option 12, is more expensive

than the other 11 options, yet much cheaper than constructing a fully expanded

AWSS plan.

 

At a Board of Supervisors’ Government Audit and Oversight Committee meeting on

Feb. 7, District 1 Supervisor Sandra Lee Fewer outlined the issue during a hearing about

the new options.

 

“In the Richmond District there are thousands of homes, wooden and built very close

together, that would be vulnerable to a fire in the case of a major earthquake or other

disaster,” Fewer said.

 

“Between the Richmond and the Sunset, we’re talking about 42,000 structures that

are not currently covered by a high-pressure emergency water system.”

 

District 4 Supervisor Katy Tang said she supports the SFPUC’s Option 12, with its co-

benefit potable pipeline, regardless of the expense.

 

“I’m really happy with what I see here in terms of Option 12 being the best option,”

Tang said. “Yes, it is the most expensive one but we have heard from the community that

they don’t care about costs, they care about safety.”

 

London Breed, president of the Board of Supervisors, mentioned the importance

of getting it right this time.

 

“As we move forward, the kinds of decisions that we make will impact our

neighborhoods for generations to come so we have to do the right thing now and focus

on quality, especially when we talk about infrastructure,” Breed said.

 

Professor Charles Scawthorn of UC Berkeley is an expert on emergency water

systems. He was brought into the planning process last year as a consultant to

the SFPUC to help formulate the new plan. Fewer asked him if hooking up just

the Sunset Reservoir would give the Richmond District an adequate water supply

after an earthquake. Scawthorn said the answer was a matter of both quantity and

reliability. If the Sunset Reservoir survives the earthquake without bursting, then, in his

opinion it would provide enough water supply for the Richmond.

 

But, reliability is a different matter because the reservoir is only a single source of water

for the west side. He referred to how the original AWSS system was designed.

 

“They built in multiple sources of supply in multiple layers,” Scawthorn said.

“Ideally, you would want to have multiple sources of supply in the western part of

the city. Therefore, beyond the Sunset Reservoir, in the long run, a second source of

supply, whether from Lake Merced or from the Pacific Ocean, is highly desirable. As San

Francisco is built out you want to have sources of supply at all four quadrants

of the City.”

 

Fewer asked him if a pump at Lake Merced was good enough to ensure an adequate

supply or if a seawater pump on the west side would be better.

 

“Ultimately, I would like to see, and I’m not paying for it, but I would like to see both

sources,” Scawthorn responded.

 

During the public comments period of the meeting Eileen Boken read a letter to

the committee that she said was written by Nancy Wuerfel, who couldn’t be there

that day. In the letter, Wuerfel suggested there was another reason the potable water

pipe of Option 12 was actually being pushed.

 

“I believe that they support Option 12 because water rate funds could be used to

offset the cost,” Boken said. “I do not agree that the city’s water rate should be

the underwriter of the city’s AWSS construction or maintenance.”

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