The California Department of Transportation (Caltrans) is alerting motorists 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 Shutoff (PSPS) periods.

When power goes out, traffic signals will start flashing and may even go dark after an outage. Caltrans operates nearly five thousand traffic signals statewide, and the department wants to make sure you are ready when the lights go out. An informational Caltrans Newsflash is available at: https://tinyurl.com/y29blz26.

Caltrans is advising motorists that traffic signals on state routes throughout Los Angeles and Ventura counties may be affected during power outages. The signals will continue to cycle regularly for approximately three hours after the outage and will then cycle to “red-flash” for about another three hours. If the outage lasts more than six hours, the signals will then go to “blackout” mode.

If a traffic signal is in blackout mode, motorists must treat it as a four-way stop — STOP until it is safe to proceed. Please review the DMV Driver’s Handbook for more details at https://tinyurl.com/yywcpkvc.

And 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 during power outages, avoid distractions, and pay close attention to other motorists, bicyclists and pedestrians in all directions. Traffic signals may take some time or require an electrician to return to normal when power is restored.

• Caltrans is already posting a “Treat as Stop Signs” advisory on electronic message signs on freeways in District 7.

• Caltrans tunnels might also be affected by a loss of power. In District 7, three tunnels — Interstate 5/Route 14, Interstate 5/Interstate 2, and Route 210/Route 210 — could lose lighting and air monitoring/ventilation systems, but backup diesel-fueled stationary generators can keep those systems running indefinitely. There would be minimal impact to a few shorter tunnels.

• Railroad crossing signals might also be affected. NEVER drive around a crossing guard in the down position. Seek an alternate route. If the crossing guard is up or signal lights are not working, motorists should exercise extreme caution before proceeding.

Southern California Edison has identified several communities in Los Angeles and Ventura counties that might be subject to power outages during the next few days when Santa Ana winds are blowing. The list of communities, maps, tips and more power outage information is available at: https://www.sce.com/safety/wildfire/psps.

Follow us for the latest information on Twitter @CaltransDist7 or check the latest road conditions on Quickmap.dot.ca.gov.