Vulnerability of California Roadways to Post-Wildfire Debris Flow

Status

Complete

Project Timeline

July 1, 2019 - June 30, 2020

Principal Investigator

Mikhail Chester

Areas of Expertise

Infrastructure Delivery, Operations, & Resilience

Campus(es)

UCLA

Project Summary

Post-wildfire debris flows represent a major challenge for roadways in California and the West. While wildfires themselves disrupt traffic and create evacuation challenges, precipitation events that occur after wildfires have the capacity to overwhelm roadways and their stormwater infrastructure, in extreme circumstances causing total failure of the asset. A post-wildfire debris flow roadway vulnerability assessment was developed for the entire state of California for both current and future conditions. The vulnerability assessment considers soil conditions, vegetative conditions, geologic conditions, precipitation (current and future), and fire risk (current and future), in addition to roadway criticality. The results from this study provide guidance for roadway mangers to identify the potential high post-fire debris flow watersheds, roadways under extremely high post-fire debris flow threat, and the changing profile of vulnerable roadways under both current long recurrence design storm events and future climate scenarios.