Post-Fire Debris Flows of 9 January 2018, Thomas Fire, Southern California: The California Geological Survey's Efforts to Map Inundation, Depth, Velocity, Initiation Areas, Precipitation, and Damages and Costs
Jeremy Lancaster, CEG
Supervising Engineering Geologist, California Geological Survey
jeremy.lancaster@conservation.ca.gov
The post-fire debris flows of 9 January 2018, killed 23 people, destroyed over 130 homes, and caused severe damage to infrastructure in Montecito and Carpinteria, California. Highway 101 was closed for 13 days, significantly impacting transportation and commerce in the region. Collectively, debris flows from this event are comparable in magnitude to the largest documented post-fire debris flows in the state, inundating over 4 km2 of land, and costing the Santa Barbara region over half a billion dollars in debris removal and damages. This presentation will focus on the documentation of the extent and magnitude of inundation, debris flow volumes and source areas; atmospheric conditions that generated intense rainfall; and, the comparison of precipitation data to debris flow initiation areas. The mapping and compilation of debris flow damages will be described to summarize economic impacts, and put into the context of historic damaging events and annualized landslide damages and costs.
Speaker Bio:
Jeremy Lancaster, CEG, is a Supervising Engineering Geologist and the program manager for the California Geological Survey’s Geologic and Landslides Mapping Program. He has worked on alluvial fan flooding and debris flow hazards for over fifteen years, including participating on the California Alluvial Fan Task Force. Mr. Lancaster has authored several peer reviewed publications on the topic of debris flow hazards.