Why Public Safety Power Shutoffs occur

Cause of Public Safety Power Shutoffs

High winds can bring tree branches and debris into contact with energized lines, damage equipment and ignite a wildfire. As a result, we may need to turn off power during severe weather to help prevent wildfires. This is called a Public Safety Power Shutoff.

How PG&E determines a Public Safety Power Shutoff

In addition to accounting for the presence of trees tall enough to strike powerlines, we carefully review a combination of factors. These include :

Humidity
Low humidity levels, 30% and below

High winds
Forecasted high winds above 19 mph with gusts above 30-40 mph

Fuel conditions
Condition of dry material on the ground and vegetation near lines

Red Flag Warning
A Red Flag Warning issued by the National Weather Service

Observations
On-the-ground, real-time observations

Weather and outage information for your area

Stay safe and informed. Monitor the following tools during a Public Safety Power Shutoff outage.

High-risk areas

The California Public Utilities Commission (CPUC) has categorized regions according to their wildfire risk. Homes and businesses with powerlines in elevated (Tier 2) or extreme (Tier 3) wildfire risk areas have a higher chance of being affected by a Public Safety Power Shutoff.

Tier 3 fire-threat areas depict areas where there is an extreme risk (including likelihood and potential impacts on people and property) of wildfires.

Tier 2 fire-threat areas depict areas where there is an elevated risk (including likelihood and potential impacts on people and property) of wildfires.

To learn more about high fire-threat areas, visit the CPUC Fire-Threat map website.