Tech for Vegetation Management After the Dixie Fire

The Increasing Prevalence of Wildfires Globally

Worldwide, wildfires are occurring with greater frequency, impacting regions such as Greece, Turkey, Australia, and California.

These fires stem from a variety of sources, including discarded cigarettes, improperly extinguished campfires, and lightning strikes. Damage to power lines, particularly in California, is also a significant contributing factor.

The Dixie Fire and PG&E's Challenges

The Dixie Fire, ignited on July 13th when a tree contacted Pacific Gas & Electric (PG&E) power lines, ultimately became the largest wildfire in California’s recorded history.

Facing substantial financial liabilities from previous wildfires between 2015-2017 and the 2018 Camp Fire which devastated Paradise, PG&E filed for Chapter 11 bankruptcy. This action was taken in an attempt to mitigate potentially tens of billions of dollars in further fire-related claims.

Following the bankruptcy proceedings, PG&E committed to a $25.5 billion settlement for all major wildfire victims and implemented changes to its board of directors.

PG&E’s Vegetation Management Protocol

Currently, PG&E employs a year-round vegetation management protocol, utilizing conventional methods for tree clearance.

After notifying landowners or homeowners of scheduled inspections, inspectors manually identify trees requiring pruning or removal. The subsequent work to address these trees can take between four to six weeks to complete.

The Enhanced Vegetation Management (EVM) Program

As part of its reorganization plan, the California Public Utilities Commission introduced measures to strengthen PG&E’s governance and operational procedures.

One such measure is the Enhanced Vegetation Management (EVM) program, designed to reduce the risk of wildfires.

This program requires PG&E to not only continue its existing vegetation management but also to assess risks posed by trees that are dead, dying, excessively tall, or have overhanging branches.

The company aims to complete 1,800 of a planned 2,400 miles of EVM work by the end of 2021.

Circuit Protection Zones and Risk Assessment

PG&E has identified Circuit Protection Zones (CPZ) as priority areas, focusing on the top 20% of regions with the highest wildfire risk.

This top 20% is further categorized by risk levels: 1%-3%, 4%-10%, and 11%-20%, with the 1%-3% range receiving the most attention for the 1,800 EVM miles.

The 1%-3% risk category alone encompasses approximately 2,422 miles.

Dixie Fire and CPZ Proximity

Analysis comparing the Dixie Fire’s origin – based on sources like the San Francisco Chronicle, Google Maps, and PG&E’s own maps – reveals that the fire occurred near CPZs with a risk level of 11%-20%.

Consequently, the probability of PG&E implementing its EVM program in the immediate Dixie Fire region this year is considered low.

The Impact of Drought and the Need for Speed

Prolonged and intensified California droughts leave little room for risk tolerance.

Effective wildfire prevention demands both access to timely information and the ability to execute operations at a corresponding scale.

Spacept’s Approach to Vegetation Hazard Detection

At Spacept, we are exploring the potential of our tools to identify vegetation hazards that contributed to the Dixie Fire.

The ability to detect encroachment could facilitate future wildfire prevention efforts and enhance utility reliability.

To investigate this, we analyzed satellite data captured on June 15th by the SPOT Satellite, focusing on the area identified by the San Francisco Chronicle as the likely fire origin near Feather River Canyon on Dixie Road.

using tech to transform vegetation management in the wake of the dixie fire

Applying the Tree Detector

We applied our Tree Detector to the satellite imagery to locate any tree or vegetation encroachment on the cleared path surrounding the power lines.

Identifying Dangerous Overgrowth

Our Tree Detector identified areas of overgrowth along the power line path.

By zooming in on a specific section and applying a mask to detect the power line path and surrounding vegetation, we generated an image highlighting areas of dangerous overgrowth.

Interpreting the Results

In the image, the blue path indicates cleared areas, red signifies high tree and vegetation density, and orange represents medium density.

Considering PG&E’s guidelines – that tree lines under 40 feet in height should be at least 15 feet from power lines – we identified several areas of significant concern that violated these standards.

In the future, PG&E and other utility companies could leverage satellite-based solutions like those offered by Spacept to proactively identify such overgrowth and optimize vegetation management resource allocation.