In San Francisco, all the emergency warning sirens were taken offline in 2019 because they were vulnerable to cybersecurity threats.
Prepare NorCal: Disaster Preparedness Resources
The Department of Emergency Management told ABC7 News they need significant funding to upgrade the siren system but the funds have not yet been allocated. So the sirens remain offline.
"The Department of Technology and DEM submitted a capital budget request for Fiscal Years 2022-2023 to fund the upgrade to the sirens along the coast," officials said in a statement. "Although funding has not yet been approved for this project, it remains the city's intention to bring the OPWS back online as quickly as funding and project implementation are available."
It's a different story across the Bay in Berkeley, where sirens with solar-powered battery backups are being installed in the hills and can be activated by phone, computer or satellite. Berkeley Fire Chief David Sprague said the sirens can emit tones and pre-recorded templates or custom messages on the fly.
VIDEO: All 119 San Francisco sirens are going silent-- for now
All 119 San Francisco sirens are going silent-- for now
Ten are up and operating and five more will be installed by the end of the year.
Joe Trainor is an expert in the design and operation of disaster warning systems at the University of Delaware's Disaster Research Center.
"Sirens are complicated," he said. "I think they're a really good first signal to search for more information but they have to work in tandem with other kinds of warning systems that give more depth and detail."
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Things like news reports and text message alerts.
Maui has scores of siren towers that can sound a single steady tone to warn of natural disasters like tsunamis and fires. So why didn't officials sound the sirens?
"It looks like in this case they had the technology in place but they didn't have the policy and they didn't have the decision-making in place to know when they would and when they wouldn't activate those systems," Trainor said.
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