Post Fire Debris Flow Quick Links

Post Fire Debris Flow Quick Links

Key Points about Post-Fire Debris Flows

Normally, vegetation absorbs rainfall, reducing runoff. However, wildfires leave the ground charred, barren, and unable to absorb water, creating conditions ripe for flash flooding and mudflow.

Flood risk remains significantly higher until vegetation is restored—up to 5 years after a wildfire.

While some floods develop over time, flash floods—particularly common after wildfires—can occur within minutes after the onset of a rainstorm. Even areas that are not traditionally flood-prone are at risk, due to changes to the landscape caused by fire.

Source: National Weather Service Post Wild Fire Flash Flood and Debris Flow Guide

Debris Flow Hazards Webinar Recording

On December 7, 2020 the California Resilience Alliance hosted a Winter Weather Outlook & Debris Flow Hazards Webinar. Don Lindsay from the California Geological Society presented on post-fire effects including erosion-induced debris flows, post-fire models currently being applied to predict hazard, and monitoring program to test models and improve ability to predict post-fire hazards. The video picks up at the Debris Flow Hazards portion of the combined webinar.

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. Hazard assessments are not updated in subsequent years.

USGS Hazard Assessment Viewer offers several assessment layers (all are in response to the design rainstorm with a peak 15-minute rainfall intensity of 24mm/hr / 0.94 inches/hr):

  • Basin / Segment Likelihood / Probability Estimates (probability of a debris flow as a percent range)
  • Basin / Segment Volume Estimates (predicted volume in cubic meters)
  • Basin / Segment Combined Hazard Estimates (likelihood + volume)

Navigating the Assessment Viewer

The default layer is basin probability. Using the layers menu in the upper right corner of the map, users can change the visible layers. Changes have to be made individually for each year. If the assessment layers do not appear on the map for a specific fire, you may need to zoom in more.

Along the top bar are option for filtering fires by name, year, and state. The filtered list appears in the left side bar.

When clicking on a fire an information box appears that provides links to downloadable Goedatabase and Shapefiles, along with a link to a pdf map version for the segment probability map.

California Large Fire Burn Scar Map (last 5 years)

Links to debris flow hazard assessment information for wildfires by county:

Alameda County


SCU Lightning Complex (2020): Combined basin hazard (likelihood + volume) per USGS assessment is low to moderate (segment probability pdf map).

 

Alpine County


Caldor Fire (2021): Combined basin hazard (likelihood + volume) per USGS assessment is mostly moderate with a few areas of high (segment probability pdf map). US Forest Service Burned Area Emergency Response (BAER) team also created an Assessment Report Summary.

Tamarack Fire (2021): Combined basin hazard (likelihood + volume) per USGS assessment is mostly moderate with a few areas of high (segment probability pdf map).

Slink Fire (2020): Combined basin hazard (likelihood + volume) per USGS assessment is mostly moderate (segment probability pdf map).

Donnell and McCormick Fire (2018): Combined basin hazard (likelihood + volume) per USGS assessment is mostly mostly moderate with some areas of high (segment probability pdf map).

 

Amador County


Caldor Fire (2021): Combined basin hazard (likelihood + volume) per USGS assessment is mostly moderate with a few areas of high (segment probability pdf map). US Forest Service Burned Area Emergency Response (BAER) team also created an Assessment Report Summary.

 

Butte County


Dixie Fire (2021): Combined basin hazard (likelihood + volume) per the USGS assessment is mostly moderate to high with some areas of low (Due to its size the Dixie fire was assessed in 3 phases: phase 1 segment probability pdf map (366,000 acres in the area south and west of Chester, Lake Almanor, and Taylorsville), phase 2 segment probability pdf map (403,500 acres to both the north and east and south and east of Chester and Lake Almanor), and phase 3 segment probability pdf map (the remaining 207,977 acres including the northwest side and southeast portion)). The USGS has also created story map that provides details about the Dixie fire, the level of debris-flow hazard immediately following the fire, and how burned watersheds responded to rainfall in the first year following the wildfire.

North Complex (2020): Combined basin hazard (likelihood + volume) per USGS assessment is moderate to high (segment probability pdf map).

Camp Fire (2018): Combined basin hazard (likelihood + volume) per USGS assessment is low to moderate with some areas of high (segment probability pdf map). Joint Agency Watershed Emergency Response Team Final Report.

 

Colusa County


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

 

Del Norte County


Smith River Complex (2023): Combined basin hazard (likelihood + volume) per USGS assessment is moderate to high (segment probability pdf map). The US Forest Service Burned Area Emergency Response (BAER) assessment team estimated that approximately51% of the Smith River Complex was either unburned/very low or low SBS, 34% was moderate and 15% was high SBS. Generally burned areas with high SBS are prone to post-fire impacts (soil burn severity maps).

SRF Lightning Complex (2023): The US Forest Service Burned Area Emergency Response (BAER) assessment team estimated that approximately 69% of the SRF Lightning Complex was either unburned/very low or low SBS, 27% was moderate and 4% was high SBS. Generally burned areas with moderate and high SBS are prone to post-fire impacts (soil burn severity map). The US Forest Service also released a Post-Fire BAER Assessment Summary.

Slater Fire (2020): Combined basin hazard (likelihood + volume) per USGS assessment is high (segment probability pdf map).

 

El Dorado County


Mosquito Fire (2022): Combined basin hazard (likelihood + volume) per USGS assessment is low to moderate with some areas of high (segment probability pdf map).

Caldor Fire (2021): Combined basin hazard (likelihood + volume) per USGS assessment is mostly moderate with a few areas of high (segment probability pdf map). US Forest Service Burned Area Emergency Response (BAER) team also created an Assessment Report Summary.

 

Fresno County


Creek Fire (2020): Combined basin hazard (likelihood + volume) per USGS assessment is moderate to high (segment probability pdf map).

 

Glenn County


August Complex (2020): Combined basin hazard (likelihood + volume) per USGS assessment is mostly moderate with some areas of high (segment probability pdf map). US Forest Service Burned Area Emergency Response (BAER) assessment for the August Complex-South fire area found approximately 52% of the 521,256 acres analyzed by the BAER team is either unburned/very low (9%) or low (43%) soil burn severity, while 44% sustained a moderate soil burn severity, and only 4% burned at high soil burn severity. For the August Complex-North fire area, approximately 61% of the 551,493 acres analyzed by the BAER team is either unburned/very low (32%) or low (29%) soil burn severity, while 31% sustained a moderate soil burn severity, and only 8% burned at high soil burn severity.

 

Humboldt County


SRF Lightning Complex (2023): The US Forest Service Burned Area Emergency Response (BAER) assessment team estimated that approximately 69% of the SRF Lightning Complex was either unburned/very low or low SBS, 27% was moderate and 4% was high SBS. Generally burned areas with moderate and high SBS are prone to post-fire impacts (soil burn severity map).

Six Rivers Lightning Complex (2022): Combined basin hazard (likelihood + volume) per USGS assessment mostly low to moderate with one larger area of high (segment probability pdf map).

Knob Fire (2021): Combined basin hazard (likelihood + volume) per USGS assessment is low to moderate (segment probability pdf map).

Red Salmon Complex (2020): Combined basin hazard (likelihood + volume) per USGS assessment is mostly moderate with some areas of high (segment probability pdf map).

 

Kern County


French Fire (2021): Combined basin hazard (likelihood + volume) per USGS assessment is mostly moderate with an area of high (segment probability pdf map).

 

Lake County


August Complex (2020): Combined basin hazard (likelihood + volume) per USGS assessment is mostly moderate with some areas of high (segment probability pdf map). US Forest Service Burned Area Emergency Response (BAER) assessment for the August Complex-South fire area found approximately 52% of the 521,256 acres analyzed by the BAER team is either unburned/very low (9%) or low (43%) soil burn severity, while 44% sustained a moderate soil burn severity, and only 4% burned at high soil burn severity. For the August Complex-North fire area, approximately 61% of the 551,493 acres analyzed by the BAER team is either unburned/very low (32%) or low (29%) soil burn severity, while 31% sustained a moderate soil burn severity, and only 8% burned at high soil burn severity.

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

 

Lassen County


Beckwourth Complex (2021): Combined basin hazard (likelihood + volume) per USGS assessment is mostly moderate with one area of high (segment probability pdf map).

Dixie Fire (2021): Combined basin hazard (likelihood + volume) per the USGS assessment is mostly moderate to high with some areas of low (Due to its size the Dixie fire was assessed in 3 phases: phase 1 segment probability pdf map (366,000 acres in the area south and west of Chester, Lake Almanor, and Taylorsville), phase 2 segment probability pdf map (403,500 acres to both the north and east and south and east of Chester and Lake Almanor), and phase 3 segment probability pdf map (the remaining 207,977 acres including the northwest side and southeast portion)). The USGS has also created story map that provides details about the Dixie fire, the level of debris-flow hazard immediately following the fire, and how burned watersheds responded to rainfall in the first year following the wildfire.

Loyalton Fire (2020): Combined basin hazard (likelihood + volume) per USGS assessment is low to moderate (segment probability pdf map).

Sheep Fire (2020): Combined basin hazard (likelihood + volume) per USGS assessment is moderate with some areas low (segment probability pdf map).

 

Los Angeles County


Department of Public Works – Debris and Mudflow Potential Forecast

Route Fire (2022): Combined basin hazard (likelihood + volume) per USGS assessment is mostly moderate (segment probability pdf map).

Bobcat Fire (2020): Combined basin hazard (likelihood + volume) per USGS assessment is moderate to high, with the high being mostly in the southern portion (segment probability pdf map). US Forest Service Burned Area Emergency Response (BAER) team also completed an assessment report to support funding requests.

Lake Fire (2020): Combined basin hazard (likelihood + volume) per USGS assessment is moderate to high (segment probability pdf map).

Ranch 2 Fire (2020): Combined basin hazard (likelihood + volume) per USGS assessment is moderate to high, with most of the high hazard area on the southern more populated side (segment probability pdf map).

Getty Fire (2019): Combined basin hazard (likelihood + volume) per USGS assessment is low to moderate (segment probability pdf map).

Saddle Ridge Fire (2019): Combined basin hazard (likelihood + volume) per USGS assessment is low to moderate (segment probability pdf map).

Tick Fire (2019): Combined basin hazard (likelihood + volume) per USGS assessment is low (segment probability pdf map).

Woolsey Fire (2018): Combined basin hazard (likelihood + volume) per USGS assessment is mostly moderate with some larger areas of high (segment probability pdf map).

 

Madera County


Washburn Fire (2022): Combined basin hazard (likelihood + volume) per USGS assessment is low to moderate (segment probability pdf map).

Creek Fire (2020): Combined basin hazard (likelihood + volume) per USGS assessment is moderate to high (segment probability pdf map).

 

Marin County


Woodward Fire (2020): Combined basin hazard (likelihood + volume) per USGS assessment is mostly low to moderate with one area of high (segment probability pdf map).

 

Mariposa County


Oak Fire (2022): Combined basin hazard (likelihood + volume) per USGS assessment is mostly moderate with one larger area of high hazard (segment probability pdf map).

Washburn Fire (2022): Combined basin hazard (likelihood + volume) per USGS assessment is low to moderate (segment probability pdf map).

Briceburg Fire (2019): Combined basin hazard (likelihood + volume) per USGS assessment is moderate (segment probability pdf map).

Ferguson Fire (2019): Combined basin hazard (likelihood + volume) per USGS assessment is mostly moderate with an area of high (segment probability pdf map).

 

Mendocino County


August Complex (2020): Combined basin hazard (likelihood + volume) per USGS assessment is mostly moderate with some areas of high (segment probability pdf map). US Forest Service Burned Area Emergency Response (BAER) assessment for the August Complex-South fire area found approximately 52% of the 521,256 acres analyzed by the BAER team is either unburned/very low (9%) or low (43%) soil burn severity, while 44% sustained a moderate soil burn severity, and only 4% burned at high soil burn severity. For the August Complex-North fire area, approximately 61% of the 551,493 acres analyzed by the BAER team is either unburned/very low (32%) or low (29%) soil burn severity, while 31% sustained a moderate soil burn severity, and only 8% burned at high soil burn severity.

 

Merced County


SCU Lightning Complex (2020): Combined basin hazard (likelihood + volume) per USGS assessment is low to moderate (segment probability pdf map).

 

Mono County


Slink Fire (2020): Combined basin hazard (likelihood + volume) per USGS assessment is mostly moderate (segment probability pdf map).

Boot Fire (2018): Combined basin hazard (likelihood + volume) per USGS assessment is mostly moderate (segment probability pdf map).

 

Monterey County


Monterey County Post-Fire Watershed Values at Risk Map

Colorado Fire (2022): Combined basin hazard (likelihood + volume) per USGS assessment is low to moderate (segment probability pdf map).

Willow Fire (2021): Combined basin hazard (likelihood + volume) per USGS assessment is high (segment probability pdf map).

Carmel Fire (2020): Combined basin hazard (likelihood + volume) per USGS assessment is mostly moderate (segment probability pdf map). 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): Combined basin hazard (likelihood + volume) per USGS assessment is moderate to high (segment probability pdf map).

River Fire (2020): Combined basin hazard (likelihood + volume) per USGS assessment is mostly low to moderate with two area of high hazard (segment probability pdf map). Cal OES and the California Department of Conservation have released a Watershed Emergency Response Team Evaluation for the River and Carmel Fires.

 

Napa County


Napa County’s GIS WERT Report Post-Fire Map

Glass Fire (2020): Combined basin hazard (likelihood + volume) per USGS assessment is mostly low to moderate with some areas of high (segment probability pdf map). Cal OES and the California Department of Conservation have released a Watershed Emergency Response Team Evaluation for the Glass Fire.

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

Kincade Fire (2019): Combined basin hazard (likelihood + volume) per USGS assessment is mostly moderate with a larger portion of high in the northern section (segment probability pdf map).

 

Nevada County


River Fire (2021): Combined basin hazard (likelihood + volume) per USGS assessment is low to moderate (segment probability pdf map).

 

Orange County


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

Jim Fire (2022): Combined basin hazard (likelihood + volume) per USGS assessment is moderate (segment probability pdf map).

Blue Ridge Fire (2020): Combined basin hazard (likelihood + volume) per USGS assessment is low to moderate (segment probability pdf map).

Bond Fire (2020): Combined basin hazard (likelihood + volume) per USGS assessment is low to moderate (segment probability pdf map). USGS Storymap on January & March 2021 Bond Fire Debris Flows.

Silverado Fire (2020): Combined basin hazard (likelihood + volume) per USGS assessment is low to moderate (segment probability pdf map).

Holy Fire (2018): Combined basin hazard (likelihood + volume) per USGS assessment is mostly high (segment probability pdf map).

 

Placer County


Mosquito Fire (2022): Combined basin hazard (likelihood + volume) per USGS assessment is low to moderate with some areas of high (segment probability pdf map).

River Fire (2021): Combined basin hazard (likelihood + volume) per USGS assessment is low to moderate (segment probability pdf map).

 

Plumas County


Beckwourth Complex (2021): Combined basin hazard (likelihood + volume) per USGS assessment is mostly moderate with one area of high (segment probability pdf map).

Dixie Fire (2021): Combined basin hazard (likelihood + volume) per the USGS assessment is mostly moderate to high with some areas of low (Due to its size the Dixie fire was assessed in 3 phases: phase 1 segment probability pdf map (366,000 acres in the area south and west of Chester, Lake Almanor, and Taylorsville), phase 2 segment probability pdf map (403,500 acres to both the north and east and south and east of Chester and Lake Almanor), and phase 3 segment probability pdf map (the remaining 207,977 acres including the northwest side and southeast portion)). The USGS has also created story map that provides details about the Dixie fire, the level of debris-flow hazard immediately following the fire, and how burned watersheds responded to rainfall in the first year following the wildfire.

Loyalton Fire (2020): Combined basin hazard (likelihood + volume) per USGS assessment is low to moderate (segment probability pdf map).

North Complex (2020): Combined basin hazard (likelihood + volume) per USGS assessment is moderate to high (segment probability pdf map).

North Complex – Claremont Fire (2020): Combined basin hazard (likelihood + volume) per USGS assessment is mostly moderate to high with some perimeter areas being low (segment probability pdf map).

Sheep Fire (2020): Combined basin hazard (likelihood + volume) per USGS assessment is moderate with some areas low (segment probability pdf map).

Walker Fire (2019): Combined basin hazard (likelihood + volume) per USGS assessment is mostly low to moderate with some areas of high (segment probability pdf map).

 

Riverside County


Bonny Fire (2023): Combined basin hazard (likelihood + volume) per USGS assessment is low to moderate (segment probability pdf map).

Fairview Fire (2022): Combined basin hazard (likelihood + volume) per USGS assessment is low to moderate (segment probability pdf map).

Jim Fire (2022): Combined basin hazard (likelihood + volume) per USGS assessment is moderate (segment probability pdf map).

Blue Ridge Fire (2020): Combined basin hazard (likelihood + volume) per USGS assessment is low to moderate (segment probability pdf map).

Snow Fire (2020): Combined basin hazard (likelihood + volume) per USGS assessment is low to moderate (segment probability pdf map).

Apple and El Dorado Fires (2020): Combined basin hazard (likelihood + volume) per USGS assessment is moderate to high (segment probability pdf map).

Tenaja Fire (2019): Combined basin hazard (likelihood + volume) per USGS assessment is low to moderate (segment probability pdf map).

Holy Fire (2018): Combined basin hazard (likelihood + volume) per USGS assessment is mostly high (segment probability pdf map).

Valley Fire (2018): Combined basin hazard (likelihood + volume) per USGS assessment is moderate to high (segment probability pdf map).

 

San Bernardino County


Sheep Fire (2022): Combined basin hazard (likelihood + volume) per USGS assessment is mostly low with an area of moderate (segment probability pdf map).

Apple and El Dorado Fires (2020): Combined basin hazard (likelihood + volume) per USGS assessment is moderate to high (segment probability pdf map).

Blue Ridge Fire (2020): Combined basin hazard (likelihood + volume) per USGS assessment is low to moderate (segment probability pdf map).

Hillside Fire (2019): Combined basin hazard (likelihood + volume) per USGS assessment is low (segment probability pdf map).

Valley Fire (2018): Combined basin hazard (likelihood + volume) per USGS assessment is moderate to high (segment probability pdf map).

 

San Diego County


Coyote Fire (2023): Combined basin hazard (likelihood + volume) per USGS assessment is low (basin probability pdf map).

Border 32 Fire (2022): Combined basin hazard (likelihood + volume) per USGS assessment is low to moderate (segment probability pdf map).

Border 13 Fire (2022): Combined basin hazard (likelihood + volume) per USGS assessment is low (segment probability pdf map).

Valley Fire (2020): Combined basin hazard (likelihood + volume) per USGS assessment is low to moderate (segment probability pdf map).

 

San Joaquin County


SCU Lightning Complex (2020): Combined basin hazard (likelihood + volume) per USGS assessment is low to moderate (segment probability pdf map).

 

San Mateo County


CZU Lightning Complex (2020): Combined basin hazard (likelihood + volume) per USGS assessment is moderate to high with some areas of low (segment probability pdf map).

 

Santa Barbara County


Alisal Fire (2021): Combined basin hazard (likelihood + volume) per USGS assessment is mostly moderate with one area of high (segment probability pdf map). US Forest Service Burned Area Emergency Response (BAER) Soil Burn Severity Maps.

Scorpion Fire (2020): Combined basin hazard (likelihood + volume) per USGS assessment is low (segment probability pdf map). This fire is in Channel Island National Park on one of the islands off the coast of California.

Cave Fire (2019): Combined basin hazard (likelihood + volume) per USGS assessment is moderate with some of the southern portions as low (segment probability pdf map).

 

Santa Clara County


SCU Lightning Complex (2020): Combined basin hazard (likelihood + volume) per USGS assessment is low to moderate (segment probability pdf map).

 

Santa Cruz County


County Resource Conservation District – Post Fire Recovery

CZU Lightning Complex (2020): Combined basin hazard (likelihood + volume) per USGS assessment is moderate to high with some areas of low (segment probability pdf map). 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. The California Department of Conservation also conducted a Boulder Creek Post-WERT Study for this fire. Santa Cruz County has also released a 2020 CZU Lightning Complex Fire Post-Fire Watershed Recovery Guide.

 

Shasta County


Dixie Fire (2021): Combined basin hazard (likelihood + volume) per the USGS assessment is mostly moderate to high with some areas of low (Due to its size the Dixie fire was assessed in 3 phases: phase 1 segment probability pdf map (366,000 acres in the area south and west of Chester, Lake Almanor, and Taylorsville), phase 2 segment probability pdf map (403,500 acres to both the north and east and south and east of Chester and Lake Almanor), and phase 3 segment probability pdf map (the remaining 207,977 acres including the northwest side and southeast portion)). The USGS has also created story map that provides details about the Dixie fire, the level of debris-flow hazard immediately following the fire, and how burned watersheds responded to rainfall in the first year following the wildfire.

McFarland Fire (2021): Combined basin hazard (likelihood + volume) per USGS assessment is moderate to high (segment probability pdf map).

Salt Fire (2021): Combined basin hazard (likelihood + volume) per USGS assessment is mostly moderate with some areas of high (segment probability pdf map).

Carr Fire (2018): Combined basin hazard (likelihood + volume) per USGS assessment is moderate to high (segment probability pdf map). US Forest Service Burned Area Emergency Response Plan.

Hirz and Delta Fires (2018): Combined basin hazard (likelihood + volume) per USGS assessment is moderate to high (segment probability pdf map).

 

Sierra County


Loyalton Fire (2020): Combined basin hazard (likelihood + volume) per USGS assessment is low to moderate (segment probability pdf map).

 

Siskiyou County


SRF Lightning Complex (2023): The US Forest Service Burned Area Emergency Response (BAER) assessment team estimated that approximately 69% of the SRF Lightning Complex was either unburned/very low or low SBS, 27% was moderate and 4% was high SBS. Generally burned areas with moderate and high SBS are prone to post-fire impacts (soil burn severity map).

Happy Camp Complex (2023): Combined basin hazard (likelihood + volume) for the Elliot and Fish fires per USGS assessment is low to moderate (segment probability pdf map). US Forest Service Burned Area Emergency Response (BAER) team estimated that approximately 80% of the Happy Camp Complex was either unburned/very low or low soil burn severity (SBS), 18% was moderate and 2% was high SBS (soil burn severity maps and burn area report).

McKinney Fire (2022): Combined basin hazard (likelihood + volume) per USGS assessment is moderate to high (segment probability pdf map).

Mountain Fire (2022): Combined basin hazard (likelihood + volume) per USGS assessment is moderate to high (segment probability pdf map).

Yeti Fire (2022): Combined basin hazard (likelihood + volume) per USGS assessment is moderate to high (segment probability pdf map).

Antelope Fire (2021): Combined basin hazard (likelihood + volume) per USGS assessment is low to moderate with an area of high (segment probability pdf map).

Lava Fire (2021): Combined basin hazard (likelihood + volume) per USGS assessment is moderate (segment probability pdf map).

McCash Fire (2021): Combined basin hazard (likelihood + volume) per USGS assessment is moderate to high (segment probability pdf map).

River Complex (2021): Combined basin hazard (likelihood + volume) per USGS assessment is moderate to high (segment probability pdf map).

Tennant Fire (2021): Combined basin hazard (likelihood + volume) per USGS assessment is low to moderate (segment probability pdf map).

Devil Fire (2020): Combined basin hazard (likelihood + volume) per USGS assessment is moderate (segment probability pdf map).

Red Salmon Complex (2020): Combined basin hazard (likelihood + volume) per USGS assessment is mostly moderate with some areas of high (segment probability pdf map).

Slater Fire (2020): Combined basin hazard (likelihood + volume) per USGS assessment is high (segment probability pdf map).

Lime Fire (2019): Combined basin hazard (likelihood + volume) per USGS assessment is moderate (segment probability pdf map).

Natchez Fire (2018): Combined basin hazard (likelihood + volume) per USGS assessment is mostly high with some areas of low to moderate (segment probability pdf map).

 

Solano County


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

 

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): Combined basin hazard (likelihood + volume) per USGS assessment is mostly low to moderate with some areas of high (segment probability pdf map). 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): Combined basin hazard (likelihood + volume) per USGS assessment is mostly low to moderate with one area high (segment probability pdf map).

LNU Lightning Complex – Walbridge Fire (2020): Combined basin hazard (likelihood + volume) per USGS assessment is mostly low to moderate with two larger areas of high (segment probability pdf map).

Kincade Fire (2019): Combined basin hazard (likelihood + volume) per USGS assessment is mostly moderate with a larger portion of high in the northern section (segment probability pdf map).

 

Stanislaus County


SCU Lightning Complex (2020): Combined basin hazard (likelihood + volume) per USGS assessment is low to moderate (segment probability pdf map).

 

Tehama County


Dixie Fire (2021): Combined basin hazard (likelihood + volume) per the USGS assessment is mostly moderate to high with some areas of low (Due to its size the Dixie fire was assessed in 3 phases: phase 1 segment probability pdf map (366,000 acres in the area south and west of Chester, Lake Almanor, and Taylorsville), phase 2 segment probability pdf map (403,500 acres to both the north and east and south and east of Chester and Lake Almanor), and phase 3 segment probability pdf map (the remaining 207,977 acres including the northwest side and southeast portion)). The USGS has also created story map that provides details about the Dixie fire, the level of debris-flow hazard immediately following the fire, and how burned watersheds responded to rainfall in the first year following the wildfire.

McFarland Fire (2021): Combined basin hazard (likelihood + volume) per USGS assessment is moderate to high (segment probability pdf map).

August Complex (2020): Combined basin hazard (likelihood + volume) per USGS assessment is mostly moderate with some areas of high (segment probability pdf map). US Forest Service Burned Area Emergency Response (BAER) assessment for the August Complex-South fire area found approximately 52% of the 521,256 acres analyzed by the BAER team is either unburned/very low (9%) or low (43%) soil burn severity, while 44% sustained a moderate soil burn severity, and only 4% burned at high soil burn severity. For the August Complex-North fire area, approximately 61% of the 551,493 acres analyzed by the BAER team is either unburned/very low (32%) or low (29%) soil burn severity, while 31% sustained a moderate soil burn severity, and only 8% burned at high soil burn severity.

 

Trinity County


Six Rivers Lightning Complex (2022): Combined basin hazard (likelihood + volume) per USGS assessment mostly low to moderate with one larger area of high (segment probability pdf map).

McFarland Fire (2021): Combined basin hazard (likelihood + volume) per USGS assessment is moderate to high (segment probability pdf map).

Monument Fire (2021): Combined basin hazard (likelihood + volume) per USGS assessment is mostly moderate with some areas of high (segment probability pdf map).

River Complex (2021): Combined basin hazard (likelihood + volume) per USGS assessment is moderate to high (segment probability pdf map).

August Complex (2020): Combined basin hazard (likelihood + volume) per USGS assessment is mostly moderate with some areas of high (segment probability pdf map). US Forest Service Burned Area Emergency Response (BAER) assessment for the August Complex-South fire area found approximately 52% of the 521,256 acres analyzed by the BAER team is either unburned/very low (9%) or low (43%) soil burn severity, while 44% sustained a moderate soil burn severity, and only 4% burned at high soil burn severity. For the August Complex-North fire area, approximately 61% of the 551,493 acres analyzed by the BAER team is either unburned/very low (32%) or low (29%) soil burn severity, while 31% sustained a moderate soil burn severity, and only 8% burned at high soil burn severity.

Red Salmon Complex (2020): Combined basin hazard (likelihood + volume) per USGS assessment is mostly moderate with some areas of high (segment probability pdf map).

Carr Fire (2018): Combined basin hazard (likelihood + volume) per USGS assessment is moderate to high (segment probability pdf map). US Forest Service Burned Area Emergency Response Plan.

 

Tulare County


KNP Complex (2021): Combined basin hazard (likelihood + volume) per USGS assessment is moderate with a few smaller areas of high (segment probability pdf map).

Windy Fire (2021): Combined basin hazard (likelihood + volume) per USGS assessment is moderate to high (segment probability pdf map).

SQF Complex – Castle Fire (2020): Combined basin hazard (likelihood + volume) per USGS assessment is mostly moderate with some areas of high (segment probability pdf map).

SQF Complex – Rattlesnake Fire (2020): Combined basin hazard (likelihood + volume) per USGS assessment is los to moderate (segment probability pdf map).

 

Tuolumne County


Donnell and McCormick Fire (2018): Combined basin hazard (likelihood + volume) per USGS assessment is mostly mostly moderate with some areas of high (segment probability pdf map).

 

Ventura County


Maria Fire (2019): Combined basin hazard (likelihood + volume) per USGS assessment is mostly moderate with one area of high (segment probability pdf map).

Hill Fire (2018): Combined basin hazard (likelihood + volume) per USGS assessment is low (segment probability pdf map).

Woolsey Fire (2018): Combined basin hazard (likelihood + volume) per USGS assessment is mostly moderate with some larger areas of high (segment probability pdf map).

 

Yolo County


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