Wildfire Damage of Geotechnical Assets

What happens when wildfires burn across retaining walls, landslides, bridges, power lines, utility trenches, rockfall draped mesh, reinforced slopes, or other geotechnical assets? The intent of this paper is to raise awareness of the risks posed to geotechnical assets due to wildfires and encourage a proactive approach to protect structures before they are impacted. In recent years, the United States has experienced a surge of large wildfires burning through locations with critical transportation assets. Case histories will include fire damage to Mechanically Stabilized Earth (MSE) walls in California’s Sequoia National Park, destroyed geohazard monitoring instrumentation in California’s Ferguson Fire, and bridges burned in multiple California National Forests and National Parks. Nationally, wildfires are burning with higher intensity and year-round instead of previously assumed spot locations during only dry seasons. This means a potential increased risk of wildfire damage to geotechnical assets should be considered in design. Depending on location, topography, and climate, engineers should evaluate potential wildfire damage with other extreme event criteria for existing and future geotechnical structures.