Caldecott Tunnel: Late scramble for generators keeps vital link open
Caltrans managed to protect the crucial Caldecott Tunnel from blackouts that were expected to roll through the East Bay Wednesday night, but officials struggled to defend their lack of planning for a situation that could have caused historic gridlock and forced people to stay home.
As crews scrambled to install four rented generators Wednesday morning, some people were left wondering what might have happened if the power had gone out unexpectedly during rush hour, with 100,000 motorists using Highway 24.
A state senator who represents the area had one word for the agency’s flatfooted response to the problem: “inconceivable.”
“You’ve got to be kidding!” said state Sen. Steve Glazer, describing his initial reaction when he heard at 5 p.m. Tuesday that the Caldecott might be closed — an outcome Caltrans managed to avoid by working overnight and through the morning to put in the generators.
Glazer, who lives in Orinda, was astonished to learn the tunnel did not have auxiliary power, despite Pacific Gas and Electric Co.’s announcement last year that it would start switching power off during times of high fire danger and despite the decadesold threat of an earthquake on the Hayward Fault.
“We’d always considered what would happen in a real fire, but in that case people wouldn’t be driving,” Caltrans spokesman Jeff Weiss said. “Now we have a new situation where (PG&E) is shutting off power as a precaution.”
Tony Tavares, Caltrans’ Bay Area director, said he learned Monday that the agency wouldn’t be able to operate the tunnel with only its existing power system. Caltrans officials had been loosely discussing the forecast of high winds and the possibility of an outage with PG&E for about a week, but the tunnel hadn’t been part of those conversations, Weiss said.
So, Tavares was “extremely surprised” when PG&E distributed maps on Monday showing the Caldecott would lose power from both its east and west sides.
The tunnel has redundant power sources running from either direction — one from Orinda to the east, the other from Oakland to the west — but they aren’t sufficient to withstand a massive regional shutoff, Tavares said. And the tunnel’s existing generators aren’t powerful enough to run all the safety equipment required by current building codes.
PG&E rushed to rent four generators — three to operate, one as backup — from an electrical contractor on Tuesday. Each one is as large and heavy as a loaded truck trailer, Weiss said.
“And we jumped into emergency mode,” Tavares told reporters gathered at the west side of the tunnel Wednesday morning.
Diesel smoke billowed from exhaust vents as PG&E, Caltrans and electrical workers scurried to build a temporary power supply system from rented equipment. A teethchattering thrum of machinery drowned out the roar of cars on the freeway.
The generators will power lights, Homeland Security cameras, the ventilation system, carbon monoxide sensors, fire suppression systems and other equipment in the tunnel over the next seven days. They will stay in place through the rest of the fire season.
The fourbore Caldecott is a vital link on Highway 24, which connects Contra Costa County to the MacArthur Maze and the Bay Bridge. One hundred thousand cars cross that corridor in each direction during the morning rush hour — then come back in the evening, Tavares said.
In June, Caltrans signed an emergency, $6 million contract for one large, 3megawatt generator, to be installed next spring, that will keep the tunnel operating during future power shutoffs. Extensive underground electrical work will be required to hook the new generators up to a nearby PG&E substation.
“This is a new normal, I think, for California moving forward,” Tavares said.
But even the timing of the emergency contract — months after PG&E started its practice of shutting off electricity in areas vulnerable to fires — raised questions. Some also wondered what Caltrans’ lastminute scramble might portend for a major earthquake. The Caldecott sits atop the Hayward Fault, and Tavares acknowledged that a strong temblor also could have knocked out electricity on both sides.
BART is adjacent to the Caldecott, but the mass transit system had no problems because it had backup infrastructure already in place.
PG&E did its first planned outages last year, targeting North Bay counties and parts of the Sierra foothills that were ravaged by fires in 2017. The company had also discussed turning off power near Chico, but didn’t follow through before the deadly Camp Fire flared up in November.
Even so, Caltrans was not prepared for a bigger shutoff when the seasonally dry, hot, gusty weather returned this year.
“I was new to the Bay Area and as soon as I heard about it I was on it,” Tavares said, noting that planned PG&E blackouts “are a rather new event.” But Glazer was baffled. “I look forward to getting all the facts on the situation when this emergency has passed,” the state senator said.
Elsewhere around the Bay Area, the Tom Lantos Tunnel near Devil’s Slide in San Mateo County will also remain open. That structure receives power from Half Moon Bay and Pacifica substations, and PG&E alerted Caltrans that the Pacifica side substation would continue operating through the outages.
The Robin Williams Tunnel on Highway 1 in Marin County north of the Golden Gate Bridge lost power, but it’s short enough that it does not have the same safety equipment as the other tunnels.