By Caltrans, District 8

The California Department of Transportation (Caltrans) is alerting the traveling public that power companies may shut off at-risk power lines to prevent sparking wildfires during wind and heat events this fire season. That could mean no power for long periods, from mountainous regions to urban areas. These power outages are known as Public Safety Power Shut-off periods.
When power goes out, traffic signals will start flashing and may even go dark after the outage. Caltrans operates nearly five thousand traffic signals statewide, and the department wants to make sure you are ready when the lights go out.
Caltrans is advising motorists that signalization on state routes throughout Riverside and San Bernardino counties may be affected during the power outages. The signals will continue to cycle regularly for approximately three hours after the outage and will then cycle to “red-flash” for another three to six hours. If the outage remains in place for more than six hours the signals will then go to “blackout” mode.
Motorists are advised that if a traffic signal is not working and no lights are showing on the signal (blackout mode), you must treat it as a four-way stop —STOP until it is safe to proceed. Review the DMV Driver’s Handbook for more details at The California Penal Code (PC 21800) (d) (1) states “The driver of any vehicle approaching an intersection which has official traffic control signals that are inoperative shall stop at the intersection and may proceed with caution when it is safe to do so.” (
Please use extreme caution and patience while you are driving during the possible power outages and pay close attention to other motorists and their movements. Know before you go! Follow Caltrans for the latest information on Facebook and Twitter. To assist in planning your commute, view live traffic conditions using QuickMap and planned lane closures.
For those with sensory disabilities requiring alternate formats (i.e. Braille, large print, sign language interpreter, etc.) and those needing information in a language other than English, contact Shane Massoud at 909-383-4416 or TTY 711 by Dec. 1, 2019.