• September 13, 2018 9:12 AM

Testing Alert and Warning Systems

Testing Alert and Warning Systems

Testing Alert and Warning Systems 120 120 Sonoma County Emergency and Preparedness Information

Sonoma County tested the alert and warning systems on September 10, 2018 and September 12, 2018 . You may have received a phone call, an alert on your mobile device, or experienced interruptions in local radio and television.  Survey requesting feedback was closed at 5pm on September 14, 2018.


September 10, 2018: Phone Call

Around 6 PM, Sonoma County called all SoCoAlert subscribers and landlines. If you missed the call, a voicemail should have been left.  Calling back will play the message again.

Sign up for SoCoAlert at www.SoCoAlert.com.

September 12, 2018: Mobile Alert, Radio and Television Interruptions

Sonoma County sent Wireless Emergency Alerts between 10 AM and 12 noon, to:

  • Healdsburg
  • Guerneville
  • Roseland
  • Glen Ellen/Kenwood
  • Penngrove

The alert should have displayed on all compatible mobile devices with a special tone and vibration, and a brief text notification.

Local radio and television broadcasted a test message using the Emergency Alert System around 12 noon.

The Details

Social Media

When posting information about this test, please tag us by using #SoCoReady

Test Objectives

  1. Test warning systems used to communicate to residents (including individuals with access or functional needs and Spanish speaking communities), across five different geographic, demographic and population density areas.
  2. Ensure the ability to communicate with emergency response agencies and affected populations.
  3. Identify any gaps in the existing systems, and make improvements for a safer, more prepared County.

Geographical Area Selection

As a part of the test, five geographical areas were chosen that represent a different threat hazard, topography, demographics and urban densities.

  1. Guerneville – Selected due to a river flood hazard scenario. Is in a mountainous area with a somewhat rural community in the unincorporated area.
  2. Glen Ellen/Kenwood – Selected due to a Wildland Urban Interface (WUI) hazard scenario.  The area is part of the valley floor with rural communities in the unincorporated area.
  3. Healdsburg – Selected to test the entire city boundary.  It has multiple hazards with a high tourist population area.
  4. Penngrove – Selected due to a train accident/hazardous materials release threat scenario.  The target area is small and linear within the unincorporated area.
  5. Roseland – Selected as a community within a city.  It is an urban setting with high population density.  This target area has significant Spanish speaking population.


We are taking a multi-pronged approach to evaluate this test.

  1. We will be asking the public to participate in an online survey.  This link will be sent out in the test messaging. The survey will ask questions like where the user was, when they received the alert, what their mobile carrier is, what their mobile operating system is and provide the ability to share questions or concerns.
  2. Staff from local first responder agencies, cities, special districts and volunteers will be strategically placed throughout the County to provide feedback. These field observers will be placed within and outside the testing areas.
  3. A random sampling will be conducted to capture people who did not receive the alert as well as those who did. This assessment will ask if the person knew about the test prior to September 12 and if they received the alert.