About Public Safety Power Shutoffs

A public safety power shutoff (PSPS) is a safety procedure utilized by electric utilities to proactively turn off power when and where weather conditions create a high wildfire risk. The practice of de-energization, which is becoming more and more frequent, is supported by the California Public Utilities Commission (CPUC) as a safety best practice.

In partnership with fire weather experts, Liberty monitors real-time weather data and forecasts and regularly tests fuel moisture during the fire season. If it is determined that the forecasted conditions meet or exceed safety thresholds, Liberty will initiate a PSPS.

Safety Thresholds:

• The Energy Release Component (measures dry fuel conditions) exceeds 92nd percentile
• Wind gusts exceed 40 miles per hour
• Fosberg Fire Weather Index (measures speed of potential fire) exceeds 50

In the event that a PSPS is a possibility, Liberty will attempt to contact customers through calls, texts, and emails using contact information on file. Customers should keep their contact information up-to-date and follow Liberty on Facebook and Twitter to receive timely PSPS updates.

What Other Wildfire Mitigation Efforts Does Liberty Have in Place to Protect Our Community?

Catastrophic wildfires have become all too common in California. Due to the dense vegetation and dry brush that characterize much of our landscape, the Lake Tahoe Basin and surrounding forested areas have been designated either "High" or "Very High" Fire Hazard Severity Zones by CAL FIRE.

Liberty is taking steps to mitigate the risk of wildfires in the communities we serve. Outlined below are the key components of our Wildfire Mitigation Plan.

View Mitigation Plan

Infrastructure Hardening

Infrastructure hardening is an ongoing system infrastructure improvement and replacement process aimed at lowering the potential of fires sparked by electric infrastructure. Over the next several years, Liberty will conduct the following improvements to support this process:

• Install covered conductors
• Replace conventional fuses with limiting fuses
• Test and replace aging poles
• Underground sections of the grid
• Remove tree attachments (electrical infrastructure attached to trees)
• Decommission the old wood structure Brockway Substation and replace with a new modern substation
• Complete system audit (inspect 100% of all poles and infrastructure in the system)

Vegetation Management

Liberty crews are deployed year-round throughout the region to inspect trees and vegetation in the vicinity of power lines. In compliance with state law and safety best practices, Liberty will trim or remove trees or branches that have grown too close to power lines in order to mitigate wildfire risk.

When trees are identified for trimming, crews are instructed to prune branches and vegetation back to a minimum of 12 feet from the high voltage power lines to maintain adequate clearance over the maintenance cycle period. Crews will additionally identify trees for removal that are dead, diseased, or structurally unsound, despite being within the acceptable clearance zone, if they have the potential to fall on power lines.

Customers should never attempt to conduct the tree trimming activities themselves, due to the risk of coming into contact with power lines during the process.

Liberty offers complimentary tree-trimming services to customers who believe a tree or branch may be hazardous to nearby electric infrastructure. If you spot a tree or branch you feel may be a hazard, please call us at 530-546-1787.