As part of PG&E’s ongoing efforts to prevent wildfires, we are strengthening the electric system with stronger poles, covered powerlines and undergrounding approximately 10,000 miles of distribution powerlines in and near high fire-threat areas. These efforts are known as system hardening.

This system hardening work will occur over several years across thousands of distribution lines in the highest fire-threat areas, and will:

  • Help reduce the risk of wildfires
  • Enhance long-term safety, especially during times of high fire-threat
  • Significantly improve reliability during winter weather
  • In certain cases, reduce Public Safety Power Shutoff (PSPS) impacts where hardening can reduce wildfire risks

Our wildfire safety and undergrounding efforts are making our system safer, more resilient and positioning us to better serve our customers and respond to our state’s evolving climate challenge.

Watch this video for more information on our system hardening work. For an interactive map showing complete and planned PG&E system hardening improvements coming up in your area, visit PSPS Planning Maps.

10,000-mile Initiative

In the summer of 2021, we announced a new, multi-year infrastructure safety initiative to underground approximately 10,000 miles of powerlines in and near high fire-threat areas.

We are prioritizing undergrounding in areas where we can have the greatest impact on reducing wildfire risk and PSPS outages for our customers. In addition, we are focusing on protecting critical facilities, like hospitals. We are also looking at a variety of factors including:

  • How accessible the area is during an emergency, in addition to the type of terrain
  • Constructability
  • Existing infrastructure (such as the number of services and transformers)
  • General vegetation in the area, along with the potential for trees to fall into lines
  • Climate change
  • Other concerns

We are planning our expanded undergrounding effort in areas that meet at least several of these considerations and will deliver the highest level of safety for our customers.

We are continuing to develop additional details on our 10,000-mile undergrounding plan. Our goal is to significantly expand our underground miles annually, increasing to approximately 1,000 miles of undergrounding per year.

Annual Undergrounding Mileage

Annual Undergrounding Mileage: Preliminary targets are under review. Final numbers will be included in the 2022 Wildfire Mitigation Plan.

Where is this work happening?


Nearly one-third of the electric lines that provide our customers with power are now in High Fire-Threat District (HFTD) areas.


This year, our system hardening work will occur across 180 distribution circuit miles in locations facing the highest wildfire risk. To ensure we are addressing the highest wildfire risk areas as conditions continue to change and evolve, we are using a new, state-of-the-art technology and prioritization model.

Preliminary Undergrounding Work Plan By County

The following counties have undergrounding projects planned through 2023. Please note, this work is subject to change as conditions and planning evolves. We are currently working on scoping and criteria for additional undergrounding projects in 2022, 2023 and 2024 and beyond. Please continue to check back regularly for additional details.

County Chart


Undergrounding is just one of the tools we utilize to reduce wildfire risks. Depending on the needs of the community, we review additional mitigation efforts including installing stronger poles and covered powerlines, conducting enhanced vegetation management, adjusting powerline safety settings, implementing PSPS outages as a last resort solution, and more ways to reduce wildfire risks.

System hardening is how we describe the installation of equipment designed and built to be more resistant to severe weather and wildfire risk. This work may include:

  • Undergrounding approximately 10,000 miles of distribution powerlines in and near high fire-threat areas as part of an unprecedented, multiyear effort
    • In some cases, poles may still exist to support remaining overhead lines and any PG&E equipment that remains overhead may be replaced with stronger equipment.
    • Equipment or lines owned by other utilities, such as a telecommunications company, may remain overhead.

  • Installing stronger and more resilient poles
  • Installing wider cross-arms to increase the separation of powerlines
    • In these cases, the removal of vegetation around the upgraded lines may be significantly greater than prior tree pruning but is necessary to meet required clearances

  • Replacing bare powerlines with larger, covered lines to reduce the risk of outages caused by vegetation, birds/animals and to eliminate the risk of bare powerlines coming into contact with one another
  • Installing additional poles between existing poles, as well as more down guy wires and anchors to support the weight of covered powerlines and to meet new utility standards
  • Removing powerlines connected to trees, also known as Tree Connects, and connecting the powerline to stronger, more resilient poles
  • Removal of overhead electrical assets in situations where customers can continue to be served through alternate means, including a Remote Grid

In order to safely perform this hardening work, we may need to address certain trees or shrubs that are located too close to the electric equipment. This work may include:

  • Pruning or cutting down dead, diseased, dying or defective trees that may compromise the powerlines
  • Maintaining a minimum clearance of 4 feet around powerlines in high fire-threat areas and establishing minimum clearances of 12 feet or more at the time of prune
  • Addressing overhanging branches and limbs 4 feet out from the lines and up to the sky
  • In some cases, cutting down trees and shrubs within 12 feet of the powerlines in order to safely install or underground new electric equipment

For more information, visit

Tree Clearing Graphic

We want you to be informed at every step in the process. As part of our system hardening work, you may experience the following:

  • In many cases, trees or shrubs will need to be cut down in order to access and safely complete the construction work.
  • Different contractor companies may perform the work depending on the project needs. All personnel are required to carry identification.
  • You may see PG&E and contractor vehicles, as well as large construction equipment, in your neighborhood. Traffic control measures will be in place and we will make every effort to limit construction noise.
  • It may be necessary to shut off power multiple times over the course of the project to safely complete work. Affected customers will receive advance notice. Please note that these are not PSPS outages.
  • Customers may experience intermittent road or lane closures, traffic delays and/or construction noise and activity. In addition, cranes and/or helicopters may also be required to complete this project.
  • We know this work can be disruptive. We appreciate your patience and are working hard to minimize the inconvenience.