Water supply was a major problem during most of the incident.
Part of the problem related to the fact that many of the units that
responded from distant areas were unable to hook up to Oakland
hydrants. When California adopted a standard 2 l/2inch threaded
connection for all hydrants, the cities of Oakland and San Francisco opted
to maintain their 3-inch connections and to keep a supply of adapters on
hand for mutual aid units. Fire departments in the area normally carry
adapters on their apparatus, but the plan called for adapters to be obtained
from the warehouse to meet incoming mutual aid strike teams at staging
areas. Since this fire occurred on a Sunday, there was a delay in obtaining
the adapters until off-duty personnel could open the warehouse and send
them to the scene on supply trucks.
Many of the incoming units were committed and discovered the
adapter problem only when they needed water to supply hoselines or refill
their tanks. This limited the ability of several units to work effectively until
they could locate a unit with an adapter, or one of the supply trucks
located them. Since some of these companies were in critical combat
areas, it was difficult for the logistics system to find them and deliver the
adapters.
The water supply on the hills was known to be a problem from
previous incidents and from risk analysis projects, including earthquake
vulnerability studies. The water system on the hills was arranged as
layered pressure zones, each supplied by a tank at a higher level. The
storage tanks served areas where the difference in elevation would
maintain static pressure in a desirable range at the delivery levels.
The tanks were kept filled by a series of electrically powered pumps,
which relayed the water from tank to tank, and the pumps were not
provided with emergency generators. If a pump at a particular level failed,
it isolated the tanks at higher levels from any capability for replenishment.
The power began to fail early in the fire, as wooden poles burned, lines
dropped, and transformers exploded. As pumps failed, the higher level
tanks would begin to run out of water. When the high voltage lines
shorted out, at 1315 hours, all of the power to the remaining pumps failed,
and the whole system on the hills began to run dry.
The demand on the system was also very high, as companies tried to
establish large handlines and master streams to establish defensive lines.
In addition, many of the homeowners were using their garden hoses to wet
down their roofs and shrubbery to guard against flying brands and embers;
some even left garden sprinklers running on their rooftops as they
evacuated. As homes burned to the ground, their water connections were
left spurting water into the rubble. All of these factors created an
unprecedented demand on the system, quickly using all of the stored water.
Companies on the hills reported hydrants going dry as early as
Sunday noon, and the supply was not restored until that night, when
portable generators were brought in to power some of the critical pumps.
It does not appear that the water supply was a deciding factor in the
outcome of the fire on the hills, since the crews were unable to make any
progress against the flames before the hydrants went dry. The strength of
the wind and the thermal forces made water almost totally ineffective to
stop the downwind progress of the fire. The available water was useful in
protecting certain positions, including some locations where firefighters
took refuge, and in covering exposures on the flanks.
In the Rockridge district there were also sections where the water
supply was known from past experiences to be weak. Many of the mains in
the area were old and inadequate, and at least 50 homes were burning by
1300 hours. San Francisco Strike Team One was assigned to this area and
around 1420 hours the Strike Team Leader was able to call back to his
department and have two of the city’s large diameter hose tenders
activated and dispatched to Oakland. The hose tenders were able to bring
in large supply lines from streets on the edge of the district to supplement
the supply.
One of the strong water supply areas was the private system
installed at the Claremont Hotel. This system provided an adequate
supply for the defensive streams that were established on the exposed side
of the hotel. While these streams were maintained in a stand-by defensive
posture, the crews were able to extend handlines up the hill to engage the
fire on Alvarado Road and some of the smaller streets overlooking the
hotel. This kept the fire from advancing further down the hill and causing
a direct exposure to the hotel.
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