Emergency assessment of post-fire debris-flow hazards for the 2013 Mountain fire, southern California

Open-File Report 2013-1249
By: , and 

Links

Abstract

Wildfire dramatically alters the hydrologic response of a watershed such that even modest rainstorms can produce dangerous flash floods and debris flows. We use empirical models to predict the probability and magnitude of debris flow occurrence in response to a 10-year rainstorm for the 2013 Mountain fire near Palm Springs, California. Overall, the models predict a relatively high probability (60–100 percent) of debris flow for six of the drainage basins in the burn area in response to a 10-year recurrence interval design storm. Volumetric predictions suggest that debris flows that occur may entrain a significant volume of material, with 8 of the 14 basins identified as having potential debris-flow volumes greater than 100,000 cubic meters. These results suggest there is a high likelihood of significant debris-flow hazard within and downstream of the burn area for nearby populations, infrastructure, and wildlife and water resources. Given these findings, we recommend that residents, emergency managers, and public works departments pay close attention to weather forecasts and National Weather Service–issued Debris Flow and Flash Flood Outlooks, Watches and Warnings and that residents adhere to any evacuation orders.

Study Area

Additional publication details

Publication type Report
Publication Subtype USGS Numbered Series
Title Emergency assessment of post-fire debris-flow hazards for the 2013 Mountain fire, southern California
Series title Open-File Report
Series number 2013-1249
DOI 10.3133/ofr20131249
Year Published 2013
Language English
Publisher U.S. Geological Survey
Publisher location Reston, VA
Contributing office(s) Geologic Hazards Science Center
Description Report: iv, 13 p.; 3 Plates: 22.09 x 30.96 inches or smaller
Country United States
State California
City Palm Springs
Online Only (Y/N) Y
Additional Online Files (Y/N) Y
Google Analytic Metrics Metrics page
Additional metadata about this publication, not found in other parts of the page is in this table