Community Alert Siren System

What is the Community Alert Siren System?

In the unlikely event of an emergency at the San Onofre Nuclear Generating Station (SONGS), federal regulations require that an alert and notification system be in place to help protect the health and safety of the public. The Community Alert Siren System is a network of sirens strategically located within the plant's Emergency Planning Zone (EPZ) to provide that service. The EPZ is the area surrounding SONGS and includes:

  • City of Dana Point
  • City of San Clemente
  • City of San Juan Capistrano
  • Marine Corps Base Camp Pendleton
  • California State Parks
  • Orange County (unincorporated areas south of Ortega Highway)

What Sound do the Sirens Make?

A valid siren alarm is a long, steady tone that lasts for approximately three minutes. This long, steady tone is the only siren sound we will use during a real emergency or during periodic testing of the system. Depending on where you are located, you may hear the tone from several different sirens at the same time. Any other sounds, such as an alternating high/low sound, may indicate a malfunction of that siren.

A short sample of the siren tone may be heard here (Windows Media, 508k). A full run of the siren tone may be heard here (Windows Media, 715k). Remember, only a full three minute siren will be used when there is a real emergency.

In the Event of a Real Emergency

The sirens are a signal to turn on your radio or television for instructions. Important emergency information will be provided by government officials. Please do not call 911 unless you have a life-threatening emergency.

Emergency information can also be found in the Customer Guide section of the Orange County South White Pages of your AT&T telephone directory.

Before an emergency strikes, register to receive emergency information using AlertOC. Registration is easy and free, and allows you to receive information by phone, email, text message, or TTY/TDD. With AlertOC, you can get important information for any type of emergency affecting the City.

Community Alert Siren System Annual Test

Wednesday, October 20, 2010, 10am until noon

Remember - This is only a test. You do not need to take action. Please do not call 911 unless you have a life-threatening emergency.

Federal regulations require that a full system test be conducted each year.

You will hear a long, steady siren sound. The sirens will be sounded several times for approximately three minutes each time.

Sirens will be heard in Dana Point, San Clemente, San Juan Capistrano, State Parks, Marine Corps Base Camp Pendleton, and throughout the unincorporated areas of Orange County within 10 miles of the plant.

In some areas, a separate test of the Public Address feature may be conducted. This feature may be used to alert local populations to other emergencies or to provide specific directions.

What Other Testing Happens Throughout the Year?

Testing of all of the equipment in the Community Alert Siren System happens on an ongoing basis year-round. Most of this testing is silent and verifies the electronics that make the system work. Four times a year, each of the sirens is activated individually for a few seconds. This quarterly test is usually completed in each city over a few hours; however, each city may have their sirens tested on a different day, so this short test may be heard in one location for several days.