Facts >> Public Safety
- Firestorm and Disaster Waiting to Happen?
The Patterson Ranch
proposed development puts 520 2-story housing units on land that is
subject to the highest intensity of shaking
(as rated by US Geological Survey) and high
risk of liquefaction (see map below). In addition,
the housing units will also be constructed on man-made fill added to the liquefaction-prone
land so the structures can be raised above flood
level (the site is less than one mile from San
Below is a map from U.S. Pipeline and Hazardous Materials Safety Administration that shows the proposed Patterson Ranch development in relation to the second highest risk natural gas transmission pipeline in the Bay Area.
According to the US Geological Survey, “When
the ground liquefies, it may lose its ability to
support buildings and other structures. Liquefaction
during large earthquakes commonly disrupts pipelines
and road networks and also may cause buildings to
settle and move down slope or toward stream banks.
Potentially hazardous areas include those along some
of the larger streams, which produce loose young
soils that are particularly susceptible to
liquefaction . . . . Many regions of man-made fill
liquefied in the 1989 Loma Prieta earthquake. The
Marina District built on fill in San Francisco
suffered some of the worst damage in 1989 (see
The first two floors of this San Francisco Marina
district apartment sank below ground due to
liquefaction. An automobile is crushed under the
third story of this building (US Geological Survey).
The buildings may withstand an earthquake—only to
become fuel for a major fire that can put Fremont
and Union City at risk.
In liquefaction, underground gas mains and water
mains rupture. This is what happened in the
Marina District in
SF during Loma Prieta. The problem wasn't only
collapsed buildings; fires also started from gas
main ruptures. And those fires could not be easily
extinguished because the water mains had ruptured as
well. Long lines of fire hoses had to be laid before
the fire department could even start fighting the
Marina fire. Magnifying the problem of a potential fire in Coyote Hills are the strong afternoon southeasterly winds coming from the San Francisco Bay less than one mile away.
With the rupture of a gas line in San Bruno in September 2010, an inferno erupted, resulting in
8 deaths and 56 homes destroyed.
Burned apartment complex in San Francisco Marina
district (US Geological Survey)
Building in SF Marina District collapsed and an area
burned. Note water on the ground from rupture of
water mains (US Geological Survey).
If Patterson Ranch
were to be built, would there be
sufficient beds and emergency services at
Washington and Kaiser Hospitals to accommodate a
public safety disaster in a development with
over 2,000 residents?
This does not
include over 1,000 residents at the Pulte development being built across from
Coyote Hills. This 15.5-acre property was sold by
the Patterson family for $63 million.
NO fire station is included in this proposed massive
development; therefore, help is unfortunately not
immediately available in the event of a public
Shouldn’t the city council have responsibility for