San Francisco’s emergency sirens will sound off for the last time next Tuesday as they prepare to undergo an upgrade.
The outdoor warning system includes 119 sirens that can be heard throughout The City at noon each Tuesday during a weekly test. Their wail has become a signature sound of San Francisco for many locals.
The upgrade is expected to cost between $2 million and $2.5 million and take up to two years, according to the Department of Emergency Management.
During the shut down, officials say there will be several other options for emergency alerts, including the Alert SF text message system, emergency alerts that go out over television and radio broadcasts and wireless emergency alerts that are more commonly used for Amber Alerts.
In addition, emergency responders and community organizations could be used to go door-to-door and reach out to vulnerable residents in emergencies, according to DEM.
“San Francisco has a multi-layered alert and warning system,” said DEM spokesperson Francis Zamora. “We have multiple redundancies.”
In a real emergency, the sirens would blast a 15-second tone repeatedly for five minutes, interspersed with spoken instructions broadcast over loudspeakers.
The last time that actually happened was in 2012, when residents on Treasure Island were alerted to potential water contamination after a water main break, according to emergency officials.
The siren system, which dates back to World War II, was last upgraded in 2005. The latest upgrade is expected to include a new operating system and hardware and stronger encryption to improve reliability and security.
While the sirens are being shut down this month, the exact timeline for the upgrades remains unclear.
In a statement, officials with DEM and Department of Technology, which manages the system, said they were seeking funding for the project in the 2020-2021 budget cycle, and that work would take 18 to 24 months to complete once funding is approved.
Officials with the Department of Technology did not immediately return messages seeking further information on the timeframe and funding for the project.