Temporary Outdoor Public Warning System Shutdown
Warning Siren Upgrade Project
General Questions
Q: What is the Outdoor Public Warning System and how does it work?
A: The Outdoor Public Warning System (OPWS) is a system of 119 sirens located throughout San Francisco. The purpose of the alarm system is to alert residents and visitors about critical life-safety emergencies like a tsunami, contaminated water supply or radiological attack.
In the event of an emergency, a 15 second tone will sound repeatedly for five minutes with audible instructions. If for any reason you cannot understand or hear the message being emitted over the alarm, tune into local news and radio stations, go online to www.sf72.org or a local news source or follow us on Twitter @SF_Emergency for further information and updates.
The San Francisco Department of Technology (DT) provides maintenance of the system. The San Francisco Department of Emergency Management (DEM) may utilize the system to send out alerts and warnings for critical life and safety incidents.
The last real-event use of the OPWS was on Treasure Island in 2012 due to potential water contamination on the island caused by a water main break.
Q: Why are the Sirens being taken out of service?
A: A prepared and resilient San Francisco means ensuring we have reliable and secure alert and warning systems. The Outdoor Public Warning System was taken off-line to address security vulnerabilities to an aging system. Prior to the pandemic, the City and County of San Francisco began exploring funding options to upgrade the system to include new hardware and encryption technologies. This project has been placed on hold pending funding availability. The last upgrade took place in 2005.
Q: If we can do without the system for two years, is it a good use of our money to upgrade it?
A: We believe in a system with redundancy and the sirens are one of many resources used to alert the public. Other resources include text, e-mail and voicecall alerts, Wireless Emergency Alerts, the Emergency Alert System and the deployment of first responders and other emergency workers.
Alert & Warning Questions
Q: What will happen if there is an emergency? How will we receive warning?
A: San Francisco uses numerous alert and warning tools to deliver emergency notifications, alerts and warnings. During the OPWS upgrade the City will still have access to AlertSF, the Emergency Alert System (EAS) and Wireless Emergency Alerts (WEA). We will also utilize traditional and social media to amplify emergency alerts. The City’s alert and warning dissemination tools include deploying first responders, disaster service workers and community based organizations to impacted areas to help warn residents.
AlertSF Advertisment
AlertSF – Text, E-Mail and Phone Call Alerts
AlertSF is San Francisco’s emergency text message, e-mail and phone call system. AlertSF issues alerts and instructions following a natural disaster, major police, fire, health emergencies or significant transportation disruptions to mobile subscribers. There are more than 137,000 AlertSF subscribers in San Francisco.
How to receive text alerts
The simplest way is to text your zip code to 888-777. You can sign up for more than one zip code just send them one at a time. For example, if you live in Bayview and work in North Beach, then text 94124 to 888-777. Then in separate message text 94133 to 888-777.
You can also visit alertsf.org to register for text alerts, e-mail and phone call alerts. By going online you can create a more compressive profile and customize the types of alerts you receive.
How to receive a phone call alert
AlertSF is also capable of sending voice alerts over the phone for the most critical life and safety emergencies. AlertSF has access to Yellow and White Page data and can send a voice alert to more than 350,000 listed phone numbers in San Francisco.
If you are not listed or not sure if you are listed in the Yellow or White pages you can still register your home phone by visiting www.alertsf.org.
Please keep in mind voice alerts over the phone are reserved for the most critical life and safety emergencies such as an incoming tsunami or contamination of the water system.
Emergency Alert System (EAS) – Radio and Television
The Emergency Alert System (EAS) is used by alerting authorities to send warnings via broadcast, cable, satellite and wireline communications pathways. Most people recognize EAS as the weekly test they may see on television or hear on the radio.
Wireless Emergency Alerts (WEA)
Wireless Emergency Alerts (WEAs) are used to send concise, text-like messages to WEA-capable mobile devices during emergency situations. WEAs are sent by your state and local public safety officials, the National Weather Service, the National Center for Missing and Exploited Children, and the President of the United States. Most people recognize WEA as the Amber Alerts they may receive on their phone.
Finally, the community has role to play as well. Many people will receive some form of alert. However, we know that not everyone will (even with the sirens in operation). This is why it is important to check on friends, family members and neighbors to make sure they know what is going on.
Q: What if the power or cell reception is offline?
A: San Francisco uses numerous alert and warning tools to deliver emergency notifications, alerts and warnings. For example, San Francisco law enforcement officers, fire fighters and other emergency workers can deploy to an impacted area to warn residents about a threat and provide instruction.
It is also important for San Franciscans to ensure they can receive emergency alerts, notifications and warnings by having a battery, hand-cranked or solar powered radio. Radio signals can continue to broadcast even when there is a local power outage.
Q: What if there is a tsunami? How will I receive warning?
A: San Francisco uses numerous alert and warning system tools to deliver emergency notifications, alerts and warnings. During the OPWS upgrade the City will still have access to AlertSF, the Emergency Alert System (EAS) and Wireless Emergency Alerts (WEA). We will also utilize traditional and social media to amplify emergency alerts. The City’s alert and warning strategies also include deploying first responders, disaster service workers and community based organizations to impacted areas to help warn residents.
People should also know nature’s warning signs: Strong ground shaking, a loud ocean roar, or the water receding are all nature’s tsunami warnings. If you’re by the water when any of these warnings happen move inland and higher ground immediately.
