The Hayward Fault: America's Most Dangerous?

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http://spatialnews.geocomm.com/dailynews/2008/mar/24/news5.html

The Hayward Fault: America's Most Dangerous?

An earthquake of M6.8 or greater on the Hayward Fault, in the heart

of the San Francisco Bay area, is increasingly likely. The last

major earthquake on the Hayward Fault was in 1868, 140 years ago:

research by the U.S. Geological Survey (USGS) and others indicate

the past five such earthquakes have been 140 years apart on average.

According to newly updated information from members of the 1868

Hayward Earthquake Alliance, a major earthquake on the Hayward fault

would impact more than 5 million people and property and contents

valued in excess of $1.5 trillion in the six counties surrounding

the fault. If the 1868 earthquake were to reoccur today, Risk

Management Solutions (RMS) estimates total economic losses to

residential and commercial properties would likely exceed $165

billion. Other factors, such as fire, damage to infrastructure and

related disruption would substantially increase the loss.

In marked contrast to Hurricane Katrina where uninsured losses were

approximately 60 to 70 percent of total economic losses, more than

95 percent of projected Hayward Fault earthquake residential losses

and 85 percent of commercial losses will be uninsured.

" Bay Area residents, businesses and local governments need to take

action now to reduce future losses. The public understands this and

has repeatedly supported bond measures for well-planned seismic

upgrade projects, such as the ongoing retrofit of BART and the Hetch

Hetchy system, " said Lou Zoback, earthquake expert from RMS.

" Public and private organizations have already invested over $30

billion to retrofit or replace vulnerable buildings and

infrastructure, but more needs to be done, " said Tom Brocher,

seismologist with the USGS. Until the Bay Bridge and BART undergo

major retrofits, they remain vulnerable to earthquakes and more than

180,000 daily commuters who currently use them could face having to

take overtaxed alternate routes for months. Similarly, until the

Hetch Hetchy aqueduct system upgrade is complete, earthquake-related

activity could cut off water for 2.4 million Bay Area residents,

according to a recent report by the Bay Area Economic Forum.

" People should realize there is a possibility that they won't be

able to drive home from work or pick up their children from school, "

said Jeanne Perkins from the Association of Bay Area Governments. " A

Hayward Fault earthquake could close 1,100 roads, including 900 in

Alameda County alone. "

Oakland and San Francisco international airports and nearly all the

region's port facilities are built on materials prone to earthquake

damage. As a result, the capacity to deliver the goods needed to

support recovery would be significantly diminished. " We hope that

information in the research being released today will promote

greater awareness among the general population and will encourage

businesses and lifeline operators to achieve greater resiliency in

our infrastructure, " said Knudsen, a representative of the

Earthquake Engineering Research Institute (EERI).

While the projected consequences of a Hayward Fault earthquake are

staggering, and similar to that of the 1868 earthquake, authors of

this newly released article are encouraged by the interest that

residents and community leaders are showing in mitigation and

preparedness. " We hope that our research will facilitate more

informed decision making on the part of local officials, " said

Brocher.

Original loss estimates will appear in an upcoming issue of

Catastrophe Risk Management magazine, and reflect analysis based on

a M6.8 earthquake on the Hayward Fault. The updated loss estimates,

presented in this news release, are based on new modeling that

suggests the 1868 Hayward earthquake was closer to M7.0.

A link to the full article will be available soon at

http://www.cat-risk.com

The report authors include Brocher, U.S. Geological Survey,

Knudsen, URS ation, Lou Zoback, Risk Management

Solutions, Jeanne Perkins, Association of Bay Area Governments,

Margaret Hellweg, University of California, Berkeley,

Savage, U.S. Geological Survey, Kathy , California Governor's

Office of Emergency Services.

The article authors are also members of the 1868 Hayward Earthquake

Alliance http://www.1868alliance.org.