SAN LUIS OBISPO COUNTY — On Tuesday and Wednesday, April 2 & 3, the Early Warning System sirens located in the Diablo Canyon Emergency Planning Zone (EPZ) will undergo regularly-scheduled low volume growl tests. Each siren throughout the EPZ will be tested individually for a period of a few seconds. This is only a test and no action is requested or required on the part of the public. These required tests help emergency officials ensure the siren system is working properly should the system be needed during an emergency.

Although the Early Warning System sirens were installed and are maintained as one of the requirements related to the operation of the Diablo Canyon Power Plant, the sirens can be used for any local emergency where there is a need for the public to take action. This may include tsunami, dam failure, or other natural or man-made disaster. During an emergency, the sounding of the sirens is an indication that the Emergency Alert System has been activated and the public should tune to a local television or radio station for emergency information and instructions.

The Early Warning System sirens cover an area extending from Cayucos to the north to the Nipomo Mesa in the south. This includes the Five Cities Area, Avila Bay, See Canyon, Price Canyon, Baywood Park/Los Osos, City of San Luis Obispo, and Morro Bay.


Additional information on the siren system, as well as emergency preparedness information, can be found at