Post Fire Debris Flow Quick Links Collection

Created: October 14, 2020

General Resources About Debris Flows After Fires

National Weather Service Post Wildfire Flash Flood and Debris Flow Guide

USGS Emergency Assessment of Post-Fire Debris-Flow Hazards – Links to each of the California fires are including in the county information below. Links for fires in other states can be found here. FAQs about USGS assessment

California Department of Conservation – Post-Fire Debris Flow Facts

California Department of Conservation – Wildfire and Debris Flow: A Geologic Hazard

Drought Influences on Post- Wildfire Flooding and Debris Flow Hazard

Forest Service Post Fire Restoration – After the Fire Dos and Don’ts

Flood After Fire Video – California Department of Water Resources

US Forest Service – Field Guide for Mapping Post-Fire Soil Burn Severity (technical document)

Debris Flow Hazard Assessment Maps & County Specific Resources

Wildfires that crossed county lines are included under each of the counties  where a burn scar was left. The impacts of a debris flow may cross into adjacent counties. If your locations of interest are near county lines, it is recommended that you also look at the neighboring county to see if there is potential risk from nearby burn scars.

USGS Hazard Assessments: depict the likelihood of debris-flow generation and estimates of flow magnitude in locations where debris flows initiate. The models do not predict downstream impacts, potential debris-flow runout paths, and the areal extent of debris-flow or flood inundation. Downloadable Goedatabase, Shapefile, and PDFs of the hazard assessment maps are available. Hazard assessments are not updated in subsequent years.

Layers Menu in the top right corner of the USGS Hazard Assessment Maps offers the following options (all are in response to the design rainstorm with a peak 15-minute rainfall intensity of 24mm/hr / 0.94 inches/hr):

• Basin / Segment Probability (probability of a debris flow as a percent range)
• Basin / Segment Volume (predicted volume in cubic meters)
• Basin / Segment Hazard (combined relative debris flow hazard)

Alameda County

SCU Lightning Complex (2020): Basin hazard per USGS assessment is low to moderate. Cal OES and the California Department of Conservation have released a Watershed Emergency Response Team Evaluation for the SCU Lightning Complex.

Alpine County

Slink Fire (2020): Basin hazard per USGS assessment is low to moderate.

Donnell and McCormick Fire (2018): Basin hazard per USGS assessment is mostly mostly moderate with some areas of high.

McCormick Fire (2017): Basin hazard per USGS assessment is moderate to high.

Butte County

North Complex (2020): Basin hazard per USGS assessment is moderate to high.

Camp Fire (2018): Basin hazard per USGS assessment is low to moderate with some areas of high.

Cherokee Fire (2017): Basin hazard per USGS assessment is mostly low with an area of moderate.

Wind Complex – Cascade Fire (2017): Basin hazard per USGS assessment is mostly low with a few areas of moderate.

Colusa County

LNU Lightning Complex – Hennessey Fire (2020): Basin hazard per USGS assessment is mostly low to moderate with a larger area of high south of Lake Berryessa. Cal OES and the California Department of Conservation have released a Watershed Emergency Response Team Evaluation for the Hennessey Fire.

Del Norte County

Slater Fire (2020): Basin hazard per USGS assessment is high. US Forest Service Burned Area Emergency Response (BAER) full report and Soil Burn Severity Maps are also available.

Eclipse Complex – Oak Fire (2017): Basin hazard per USGS assessment is moderate to high.

Orleans Complex – Haypress Fire (2017): Basin hazard per USGS assessment is low to moderate with an area of high.

Orleans Complex – Ukonom Fire (2017): Basin hazard per USGS assessment is low to moderate.

Fresno County

Creek Fire (2020): Basin hazard per USGS assessment is moderate to high. US Forest Service Burned Area Emergency Response (BAER) Soil Burn Severity Maps are also available.

Glenn County

August Complex (2020): Basin hazard per USGS assessment is mostly moderate with some areas of high. US Forest Service Burned Area Emergency Response (BAER) Soil Burn Severity Maps are also available. A full BAER report is also available for the South Zone.

Humboldt County

Red Salmon Complex (2020): Basin hazard per USGS assessment is mostly moderate with some areas of high. US Forest Service Burned Area Emergency Response (BAER) Soil Burn Severity Maps are also available, including a text description.

Lake County

August Complex (2020): Basin hazard per USGS assessment is mostly moderate with some areas of high. US Forest Service Burned Area Emergency Response (BAER) Soil Burn Severity Maps are also available. A full BAER report is also available for the South Zone.

LNU Lightning Complex – Hennessey Fire (2020): Basin hazard per USGS assessment is mostly low to moderate with a larger area of high south of Lake Berryessa. Cal OES and the California Department of Conservation have released a Watershed Emergency Response Team Evaluation for the Hennessey Fire.

Mendocino Lake Complex – Sulfur Fire (2017): Basin hazard per USGS assessment is low to moderate.

Lassen County

Loyalton Fire (2020): Basin hazard per USGS assessment is low to moderate.

Sheep Fire (2020): Basin hazard per USGS assessment is moderate with some areas low.

Los Angeles County

Department of Public Works – Debris and Mudflow Potential Forecast

Bobcat Fire (2020): Basin hazard per USGS assessment is moderate to high, with the high being mostly in the southern portion. US Forest Service Burned Area Emergency Response (BAER) Soil Burn Severity Maps are also available.

Lake Fire (2020): Basin hazard per USGS assessment is moderate to high. US Forest Service Burned Area Emergency Response (BAER) full report and Soil Burn Severity Maps are also available.

Ranch 2 Fire (2020): Basin hazard per USGS assessment is high. US Forest Service Burned Area Emergency Response (BAER) full report and  Soil Burn Severity Maps are also available.

Getty Fire (2019): Basin hazard per USGS assessment is low to moderate.

Saddle Ridge Fire (2019): Basin hazard per USGS assessment is low to moderate.

Tick Fire (2019): Basin hazard per USGS assessment is low.

Woolsey Fire (2018): Basin hazard per USGS assessment is mostly moderate with some larger areas of high.

Creek Fire (2017): Basin hazard per USGS assessment is moderate to high.

La Tuna Fire (2017): Basin hazard per USGS assessment is moderate to high.

Rye Fire (2017): Basin hazard per USGS assessment is low.

Skirball Fire (2017): Basin hazard per USGS assessment is low to moderate.

Madera County

Creek Fire (2020): Basin hazard per USGS assessment is moderate to high. US Forest Service Burned Area Emergency Response (BAER) Soil Burn Severity Maps are also available.

Railroad Fire (2017): Basin hazard per USGS assessment is low to moderate with two small areas of high.

South Fork Fire (2017): Basin hazard per USGS assessment is low to moderate.

Marin County

Woodward Fire (2020): Basin hazard per USGS assessment is mostly low to moderate with one area of high.

Mariposa County

Briceburg Fire (2019): Basin hazard per USGS assessment is moderate.

Detwiler Fire (2017): Basin hazard per USGS assessment is moderate with a few areas of high.

Railroad Fire (2017): Basin hazard per USGS assessment is low to moderate with two small areas of high.

South Fork Fire (2017): Basin hazard per USGS assessment is low to moderate.

Mendocino County

August Complex (2020): Basin hazard per USGS assessment is mostly moderate with some areas of high. US Forest Service Burned Area Emergency Response (BAER) Soil Burn Severity Maps are also available. A full BAER report is also available for the South Zone.

Mendocino Lake Complex – Redwood Valley Fire (2017): Basin hazard per USGS assessment is mostly moderate with one area of high.

Merced County

SCU Lightning Complex (2020): Basin hazard per USGS assessment is low to moderate. Cal OES and the California Department of Conservation have released a Watershed Emergency Response Team Evaluation for the SCU Lightning Complex.

Modoc County

Cove Fire (2017): Basin hazard per USGS assessment is low to moderate.

Parker 2 Fire (2017): Basin hazard per USGS assessment is mostly moderate.

Steele Fire (2017): Basin hazard per USGS assessment is low.

Mono County

Slink Fire (2020): Basin hazard per USGS assessment is low to moderate.

Boot Fire (2018): Basin hazard per USGS assessment is moderate.

Slinkard Fire (2017): Basin hazard per USGS assessment is moderate.

Monterey County

Monterey County Post-Fire Watershed Values at Risk Map

Carmel Fire (2020): Basin hazard per USGS assessment is low to moderate. Cal OES and the California Department of Conservation have released a Watershed Emergency Response Team Evaluation for the River and Carmel Fires.

Dolan Fire (2020): Basin hazard per USGS assessment is moderate to high. US Forest Service Burned Area Emergency Response (BAER) Soil Burn Severity Maps are also available. The Forest Service has also released its Dolan Fire Burn Area Report.

River Fire (2020): Basin hazard per USGS assessment is mostly low to moderate with two area of high hazard. Cal OES and the California Department of Conservation have released a Watershed Emergency Response Team Evaluation for the River and Carmel Fires.

Napa County

Glass Fire (2020): Basin hazard per USGS assessment is mostly low to moderate with some areas of high. Cal OES and the California Department of Conservation have released a Watershed Emergency Response Team Evaluation for the Glass Fire. Napa County has also created a WERT Map for the Glass Fire.

LNU Lightning Complex – Hennessey Fire (2020): Basin hazard per USGS assessment is mostly low to moderate with a larger area of high south of Lake Berryessa. Cal OES and the California Department of Conservation have released a Watershed Emergency Response Team Evaluation for the Hennessey Fire. Napa County has also created a WERT Map for the LNU Lightning Complex – Hennessey Fire.

Kincade Fire (2019): Basin hazard per USGS assessment is mostly moderate with a larger portion of high in the northern section.

Atlas Fire (2017): Basin hazard per USGS assessment is low to moderate with one small area of high.

Nuns Fire (2017): Basin hazard per USGS assessment is low to moderate with a few areas of high in the northern portion.

Tubbs Fire (2017): Basin hazard per USGS assessment is low to moderate.

Nevada County

Farad Fire (2017): Basin hazard per USGS assessment is low to moderate.

Wind Complex – Lobo Fire (2017): Basin hazard per USGS assessment is low with a few areas of moderate.

Wind Complex – McCourtney Fire (2017): Basin hazard per USGS assessment is low.

Orange County

Orange County Public Work’s Homeowners’ Guide for Flood, Debris, and Erosion Control after Fires

Blue Ridge Fire (2020): Basin hazard per USGS assessment is low to moderate.

Bond Fire (2020): Basin hazard per USGS assessment is low to moderate.

Silverado Fire (2020): Basin hazard per USGS assessment is low to moderate.

Holy Fire (2018): Basin hazard per USGS assessment is mostly high.

Canyon Fire (2017): Basin hazard per USGS assessment is low to moderate.

Canyon 2 Fire (2017): Basin hazard per USGS assessment is low to moderate.

Plumas County

Loyalton Fire (2020): Basin hazard per USGS assessment is low to moderate.

North Complex (2020): Basin hazard per USGS assessment is moderate to high.

North Complex – Claremont Fire (2020): Basin hazard per USGS assessment is mostly moderate to high with some perimeter areas being low.

Sheep Fire (2020): Basin hazard per USGS assessment is moderate with some areas low.

Walker Fire (2019): Basin hazard per USGS assessment is mostly low to moderate with some areas of high.

Minerva 5 Fire (2017): Basin hazard per USGS assessment is moderate.

Riverside County

Blue Ridge Fire (2020): Basin hazard per USGS assessment is low to moderate.

Snow Fire (2020): Basin hazard per USGS assessment is low to moderate. US Forest Service Burned Area Emergency Response (BAER) Burned Area Reflectance Classification Maps are also available. The Forest Service has also released its Snow Fire Burn Area Report.

Apple and El Dorado Fires (2020): Basin hazard per USGS assessment is moderate to high. US Forest Service Burned Area Emergency Response (BAER) Soil Burn Severity and Slope Maps are also available for the Apple Fire and Soil Burn Severity Maps for the El Dorado Fire. The Forest Service has also released its El Dorado Fire Burn Area Report and Apple Fire Burn Area Report. On September 30 Riverside County hosted a Flood After Fires Community Meeting for the Apple Fire.

Tenaja Fire (2019): Basin hazard per USGS assessment is low to moderate.

Holy Fire (2018): Basin hazard per USGS assessment is mostly high. The County has released the California Geological Survey’s Holy Fire Debris Flow Inundation Hazard Assessment within Riverside County Report

Canyon Fire (2017): Basin hazard per USGS assessment is low to moderate.

Canyon 2 Fire (2017): Basin hazard per USGS assessment is low to moderate.

Wildomar Fire (2017): Basin hazard per USGS assessment is low.

San Bernardino County

Apple and El Dorado Fires (2020): Basin hazard per USGS assessment is moderate to high. US Forest Service Burned Area Emergency Response (BAER) Soil Burn Severity and Slope Maps are also available for the Apple Fire and Soil Burn Severity Maps for the El Dorado Fire. The Forest Service has also released its El Dorado Fire Burn Area Report and Apple Fire Burn Area Report.

Blue Ridge Fire (2020): Basin hazard per USGS assessment is low to moderate.

Hillside Fire (2019): Basin hazard per USGS assessment is low.

San Diego County

Valley Fire (2020):  Basin hazard per USGS assessment is low to moderate. US Forest Service Burned Area Emergency Response (BAER) Soil Burn Severity, Debris Flow, and Erosion Maps are also available. The Forest Service has also released several additional reports related to post fire hazards from the Valley Fire: Burn Area Report, BAER Assessment Specialist Report – Geological Hazards, Soils Report, and a Post-Fire Watershed Response: Hydrology Report.

Gate Fire (2017): Basin hazard per USGS assessment is low to moderate.

Lilac Fire (2017): Basin hazard per USGS assessment is low.

Jennings 2 Fire (2017): Basin hazard per USGS assessment is low to moderate.

San Joaquin County

SCU Lightning Complex (2020): Basin hazard per USGS assessment is low to moderate. Cal OES and the California Department of Conservation have released a Watershed Emergency Response Team Evaluation for the SCU Lightning Complex.

San Mateo County

CZU Lightning Complex (2020): Basin hazard per USGS assessment is moderate to high with some areas of low. Cal OES and the California Department of Conservation have released a Watershed Emergency Response Team Evaluation for the CZU Lightning Complex. Map showing evacuation zones and debris flow risk throughout the CZU Lightning Complex fire zone.

Santa Barbara County

Scorpion Fire (2020): Basin Hazard per USGS assessment is low. This fire is in Channel Island National Park on one of the islands off the coast of California.

Cave Fire (2019): Basin hazard per USGS assessment is moderate with some of the southern portions low.

Thomas Fire (2017): Basin hazard per USGS assessment is moderate too high.

Whittier Fire (2017): Basin hazard per USGS assessment is moderate to high.

Santa Clara County

SCU Lightning Complex (2020): Basin hazard per USGS assessment is low to moderate. Cal OES and the California Department of Conservation have released a Watershed Emergency Response Team Evaluation for the SCU Lightning Complex.

Santa Cruz County

County Resource Conservation District – Post Fire Recovery

CZU Lightning Complex (2020): Basin hazard per USGS assessment is moderate to high with some areas of low. A Memorandum “Landslide and Debris Flow Hazard Conditions Now Threatening the San Lorenzo Valley, Caused by the CZU Wildfire” to the District Board of Directors and public also provides addition information about the post-fire risks in the area. Cal OES and the California Department of Conservation have released a Watershed Emergency Response Team Evaluation for the CZU Lightning Complex. The California Department of Conservation also conducted a Boulder Creek Post-WERT Study for this fire. Map showing evacuation zones and debris flow risk throughout the CZU Lightning Complex fire zone. Santa Cruz County Potential Debris Flow Hazard Area Map. Recordings of County Debris Flow Town Hall Meetings – District Five (11/12/20) and District Three (11/13/20). Recording of the County Board of Supervisors presentation Post-CZU lightning Complex Fire Debris Flow Hazards (9/29/20). Santa Cruz County has also released a 2020 CZU Lightning Complex Fire Post-Fire Watershed Recovery Guide – Learn how to stay safe, protect your property, and preserve our natural resources.

Sierra County

Loyalton Fire (2020): Basin hazard per USGS assessment is low to moderate.

Farad Fire (2017): Basin hazard per USGS assessment is low to moderate.

Siskiyou County

Devil Fire (2020): Basin hazard per USGS assessment is moderate. US Forest Service Burned Area Emergency Response (BAER) Soil Burn Severity Maps are also available.

Red Salmon Complex (2020): Basin hazard per USGS assessment is mostly moderate with some areas of high. US Forest Service Burned Area Emergency Response (BAER) Soil Burn Severity Maps are also available, including a text description.

Slater Fire (2020): Basin hazard per USGS assessment is high. US Forest Service Burned Area Emergency Response (BAER) full report and Soil Burn Severity Maps are also available.

Lime Fire (2019): Basin hazard per USGS assessment is moderate.

Eclipse Complex – Abney Fire (2017): Basin hazard per USGS assessment is moderate to high.

Eclipse Complex – Cedar Fire (2017): Basin hazard per USGS assessment is mostly moderate.

Eclipse Complex – Oak Fire (2017): Basin hazard per USGS assessment is moderate to high.

Salmon Complex Fire (2017): Basin hazard per USGS assessment is moderate to high.

Solano County

LNU Lightning Complex – Hennessey Fire (2020): Basin hazard per USGS assessment is mostly low to moderate with a larger area of high south of Lake Berryessa. Cal OES and the California Department of Conservation have released a Watershed Emergency Response Team Evaluation for the Hennessey Fire.

Atlas Fire (2017): Basin hazard per USGS assessment is low to moderate with one small area of high.

Sonoma County

County of Sonoma Post-Fire Hazard Assessment Map

Sonoma County – Preparing for Rain After Wildfires

How to Prepare Burned Properties for Rain after the Glass Fire

City of Santa Rosa – Preparing for Rain After Wildfires

Glass Fire (2020): Basin hazard per USGS assessment is mostly low to moderate with some areas of high. Cal OES and the California Department of Conservation have released a Watershed Emergency Response Team Evaluation for the Glass Fire.

LNU Lightning Complex – Meyers Fire (2020): Basin hazard per USGS assessment is mostly low to moderate with one area high.

LNU Lightning Complex – Walbridge Fire (2020): Basin hazard per USGS assessment is mostly low to moderate with two larger areas of high.

Kincade Fire (2019): Basin hazard per USGS assessment is mostly moderate with a larger portion of high in the northern section. Sonoma County also has a post-fire hazard assessment map that includes debris flow.

Nuns Fire (2017): Basin hazard per USGS assessment is low to moderate with a few areas of high in the northern portion.

Pocket Fire (2017): Basin hazard per USGS assessment is low to moderate with one area of high.

Tubbs Fire (2017): Basin hazard per USGS assessment is low to moderate.

Sonoma County also has a Post Fire Debris Flow Likelihood for Nuns, Tubbs and Atlas Fires GIS Maps

Stanislaus County

SCU Lightning Complex (2020): Basin hazard per USGS assessment is low to moderate. Cal OES and the California Department of Conservation have released a Watershed Emergency Response Team Evaluation for the SCU Lightning Complex.

Tehama County

August Complex (2020): Basin hazard per USGS assessment is mostly moderate with some areas of high. US Forest Service Burned Area Emergency Response (BAER) Soil Burn Severity Maps are also available. A full BAER report is also available for the South Zone.

Trinity County

August Complex (2020): Basin hazard per USGS assessment is mostly moderate with some areas of high. US Forest Service Burned Area Emergency Response (BAER) Soil Burn Severity Maps are also available. A full BAER report is also available for the South Zone.

Red Salmon Complex (2020): Basin hazard per USGS assessment is mostly moderate with some areas of high. US Forest Service Burned Area Emergency Response (BAER) Soil Burn Severity Maps are also available, including a text description.

Helena and Fork Fire (2017): Basin hazard per USGS assessment is moderate with two areas of high.

Tulare County

SQF Complex – Castle Fire (2020): Basin hazard per USGS assessment is mostly moderate with some areas of high. US Forest Service Burned Area Emergency Response (BAER) full report and Soil Burn Severity and Debris Flow Maps are also available along with a text description of the soil burn severity map.

SQF Complex – Rattlesnake Fire (2020): Basin hazard per USGS assessment is los to moderate.

Pier Fire (2017): Basin hazard per USGS assessment is moderate to high.

Tuolumne County

Donnell and McCormick Fire (2018): Basin hazard per USGS assessment is mostly moderate with some areas of high.

McCormick Fire (2017): Basin hazard per USGS assessment is moderate to high.

Ventura County

Maria Fire (2019): Basin hazard per USGS assessment is mostly moderate with one area of high.

Hill Fire (2018): Basin hazard per USGS assessment is low.

Woolsey Fire (2018): Basin hazard per USGS assessment is mostly moderate with some larger areas of high.

Thomas Fire (2017): Basin hazard per USGS assessment is moderate too high.

Yolo County

LNU Lightning Complex – Hennessey Fire (2020): Basin hazard per USGS assessment is mostly low to moderate with a larger area of high south of Lake Berryessa. Cal OES and the California Department of Conservation have released a Watershed Emergency Response Team Evaluation for the Hennessey Fire.

Yuba County

Wind Complex – Cascade Fire (2017): Basin hazard per USGS assessment is mostly low with a few areas of moderate.