The table below presents an overview of studies that have collected soil hydraulic data and applied it to model post-wildfire conditions. These investigations focused on watersheds that have experienced fire-related disturbances, with models undergoing calibration to account for fire-induced changes. The comparison of calibrated values from pre-fire to post-fire scenarios provides insight into parameter adjustments, which can guide hydrologic modelers in adapting parameters for various hydrologic methods. The primary purpose of this table is to offer post-wildfire modelers examples of burned soil parameter values and adjustments. The table compiles information for modeling post-wildfire events, including:

  1. The location that experienced a fire event and its burn severity
  2. Soil loss methods (with the Green and Ampt method being the most commonly used)
  3. Soil and vegetation types
  4. Burn-to-unburn ratios that can be applied to calibrated unburned watersheds to reflect burned conditions


Journal

Location

Fire Event and Year

Soil Collection Date

Storm Event

Burn Severity

Soil Loss Method

Transform Method

Burn/Unburn Ratios

Burned Soil Parameters (All values reported in metric units)

Soil Type

Vegetation

Notes

Ebel, Brian A., and John A. Moody. “Parameter Estimation for Multiple Post‐Wildfire Hydrologic Models.” Hydrological Processes, vol. 34, no. 21, 4 Aug. 2020, pp. 4049–4066, https://doi.org/10.1002/hyp.13865. Accessed 7 Jan. 2022.

Santa Barbara County, Ventura, County, California

December 2017  - January 2018 Thomas Fire


  • Jan 11-12, 2018
  • March 14, 2018

Not Available

  • Santa Barbara County 
    • 1% burned at high severity
    • 79% burned at moderate severity
    • 16% burned at low severity
    • 4% unburned
  • Ventura County
    • 1% burned at high severity
    • 52% burned at moderate severity
    • 34% burned at low severity
    • 13% unburned


  • Green and Ampt
  • Smith-Parlange
  • Richard's Equation

NA

Saturated Hydraulic Conductivity 

  • 0.37

Sorptivity

  • 0.36

Wetting Front

  • 0.66

Saturated Soil Content

  • 0.85
  • Saturated Hydraulic Conductivity (mm/hr)
    • Mean (geometric) = 29.1
    • Mean (arithmetic) = 74.8
    • Stdev = 119
    • Median = 40.9
  • Wetting Front (m) 
    • Mean (geometric) = 0.1
    • Mean (arithmetic) = 12
    • Stdev = 31
    • Median = 0.2
  • \theta_s (cm^3/cm^3)
    • Mean (geometric) = 0.61
    • Mean (arithmetic) = 61
    • Stdev = 0.06
    • Median = 0.61
  • \alpha(cm^{-1})
    • Mean (geometric) = 0.187
    • Mean (arithmetic) = .284
    • Stdev = 0.455
    • Median = 0.195
  • N
    • Mean (geometric) = 1.234
    • Mean (arithmetic) = 1.236
    • Stdev = 0.064
    • Median = 1.219
  • \theta_r (cm^3/cm^3)
    • Mean (geometric) = undefined
    • Mean (arithmetic) = 0
    • Stdev = 0.01
    • Median = 0
  • Sorptivity mm/hr^{0.5}

    • Mean (geometric) = 1.7
    • Mean (arithmetic) = 7.8
    • Stdev = 15
    • Median = 2.9

Table 2 of report 

Loam, gravelly clay loam, channery loam, channery silt clay loam, clay loam, stony fine sandy loam


Table 1 of report

Chaparral vegetation and manzanita

  • Recommended starting burned parameters
    • Hydraulic Conductivity = 20 mm/hr
    • Sorptivity = 6 mm/hr^.5
    • Wetting Front = 1.6 mm
  • Table 4 of report compares burned parameters against other studies
  • Measurements made at the top 1 cm of soil
  • Measurements made using Mini Disk Infiltrometer

Rengers, F. K., McGuire, L. A., Kean, J. W., Staley, D. M., & Youberg, A. (2019). Progress in simplifying hydrologic model parameterization for broad applications to post‐wildfire flooding and debris‐flow hazards. Earth Surface Processes and Landforms44(15), 3078–3092.  https://doi.org/10.1002/esp.4697

San Gabriel Mountains

August - September 2009 Station Fire

Not Available

18 January 2010

Moderate to High

Green and Ampt

Kinematic Wave

Not available

  • Hydraulic Conductivity (mm/hr)
    • Mean (geometric) = 7.7
    • Mean (arithmetic) = 8.7
    • Median = 7
  • Hillslope Manning's Roughness
    • Mean (geometric) = 0.07
    • Mean (arithmetic) = 0.09
    • Median = 0.07
  • Hillslope Manning's Roughness Equations
    • n_{eff}=0.0342A^{-0.401} (best fit effective Manning's roughness as a function of Area)
    • n = {kh^{1/6}/{\sqrt{g}ln(h/z_0-C)}
      • k=0.41 (von Karmen's constant)
      • C = 1
      • z_0 = D_{50} (particle size)
      • h = peak flow depth


Not mentioned

Chaparral

  • Model parameters matched well for timing but did not match well or matching magnitude
  • Separating hillslope and channel routing (separate manning's roughness) performs better.
    • Channel roughness is more sensitive to debris peak flow timing than hillslopes
  • Potentially can use particle size measurements to parameterize models
  • Hydraulic Conductivity and Manning's roughness mean values computed from Table 1 of report



Liu, T., McGuire, L.A., A. Youberg, Gorr, A. and Rengers, F.K. (2023). Guidance for parameterizing post‐fire hydrologic models with in situ infiltration measurements. Earth Surface Processes and Landforms. doi:https://doi.org/10.1002/esp.5633.

  • Pinal Mountains
  • Gila National Forest, New Mexico
  • Superstition Mountains, Arizona
  • Tonto National Forest, Arizona


  • May 2017 Pinal Fire
  • May 2018 Buzzard Fire
  • June 2019 Woodbury Fire
  • June 2020 Bush Fire


  • Pinal - 20 measurements on June 2020
  • Buzzard - 14 measurements June 2018
  • Woodbury - 24 measurements September 2019
  • Bush - 15 measurements September 2020


Design Storms

  • Pinal - 98% Burned at moderate to high
  • Buzzard - 99% burned at moderate to high severity
  • Woodbury - 85% low severity
  • Bush - 100% moderate to high severity


Green and Ampt

Kinematic Wave

Not available

Dataset available at:

https://www.sciencebase.gov/catalog/item/5fa0924fd34e198cb7919339


https://www.hydroshare.org/resource/96351adbdacc45e793d8fb5a740d8ac4/

Pinal - Sandy Loam

Buzzard - Silt Loam

Bush - Sandy Loam

Woodbury - Sandy Loam

    • Pinal - Chaparral
    • Buzzard - Ponderosa Pine, Doglas Fur
    • Woodbury - Sonoran Desert shrubs
    • Bush - Sonoran Desert shrubs, grassland plants, mountain shrubs


  • Derived best fit Kse-Hse curves from MDI measurements for 1st Quartile and 3rd Quartile Design Storms.
  • Best fit Kse-Hse curves derived from study performed better than arithmetic mean, harmonic mean, geometric mean, and median when parameterizing soil parameters
  • For frequent AEP less than 1 year, use the geometric mean or median of MDI measurements (point measurements of soil hydraulics)
  • Arithmetic mean of MDI measurements appears to underestimate simulated flows
  • Watershed scale soil parameters are sensitive to rainfall intensity
    • Greater intensity use higher Ksat and Hf
    • Lower intensity use lower Ksat and Hf
  • Measurements made at the top 1 cm of soil

Pradhan, N.R.; Floyd, I.

Event Based Post-Fire Hydrological

Modeling of the Upper Arroyo Seco

Watershed in Southern California.

Water 2021, 13, 2303. https://

doi.org/10.3390/w13162303

Los Angeles National Forest, Upper Arroyo Seco

August 2009 Station Fire

Not Available

  • Jan 18, 2010
  • Feb 27, 2020

95% burned at low (18%), Medium (42%) to high (35%) severity

Green And Ampt

Diffusion Wave

Saturated Hydraulic Conductivity

  • High = 0.1
  • Medium = 0.2
  • Low = 0.3

Manning's Roughness

  • High = 0.15
  • Medium = 0.18
  • Low = 0.2


Not Available

Sandy Loam

Not Mentioned


  • Use SERVES (Soil Moisture Estimation of Root zone through Vegetation index based Evapotranspiration fraction and Soils properties) to estimate soil moisture to parameterize K_{unsaturated}


Ebel, B.A., Rengers, F.K. and Tucker, G.E. (2016). Observed and simulated hydrologic response for a first-order catchment during extreme rainfall 3 years after wildfire disturbance. Water Resources Research, 52(12), pp.9367–9389. doi:https://doi.org/10.1002/2016wr019110.

Sugarloaf Mountain Boulder, Colorado

September 2010 Fourmile Canyon

  • 14 measurements November 7-11, 2013 at burned site
  • 11 measurements at unburned site
  • 4 measurements made at weathered bedrock summer of 2014



September 9 - 16, 2013

Not mentioned

Richard's Equation

Diffusion wave

Saturated Hydraulic Conductivity

  • Mean (Geometric) - 0.02
  • Median - 0.21
  • Min - 0
  • Max - 1.29


Sorptivity

  • Mean (Arithmetic) - 0.73


(Table 2 report)

Saturated Hydraulic Conductivity (mm/hr)

  • Mean (Geometric) - 5.6
  • Median - 188
  • Stdev - 188
  • Min - 0
  • Max - 628

Sorptivity (mm/hr^{0.5})

  • Mean (Arithmetic) - 11.8
  • Stdev - 9

Soil water Content Saturated

  • Burned soil = 0.49
  • Unburned soil = 0.46

Soil water Content Residual

  • Burned soil = 0.008
  • Unburned soil = 0.01

Alpha

  • Burned soil = 3.97
  • Unburned soil = 7.05

N (soil water retention curve fitting parameter)

  • Burned = 1.401
  • Unburned = 1.446

(Table  1 and 2 of report)

Gravelly Sand

Douglas fire, Limber pine, and some Aspen

  • Soil property measurements 3 years after burn
  • Weathered Bedrock
    • Mean (geometric) = 63.7
    • Median = 100.3
    • Stdev = 47.5
    • Max = 116.4
    • Min = 14.2
    • Mean (arithmetic) = 13.1
    • Stdev = 6.1
    • Hydraulic Conductivity
    • Sorptivity
  • Measurements made at the top 1 cm of soil

McGuire, L.A., Youberg, A.M., Rengers, F.K., Abramson, N.S., Ganesh, I., Gorr, A.N., Hoch, O., Johnson, J.C., Lamom, P., Prescott, A.B., Zanetell, J. and Fenerty, B. (2021). Extreme Precipitation Across Adjacent Burned and Unburned Watersheds Reveals Impacts of Low Severity Wildfire on Debris‐Flow Processes. Journal of Geophysical Research: Earth Surface, 126(4). doi:https://doi.org/10.1029/2020jf005997

Superstition Mountains, Arizona


Northern edge of the Woodbury Fire perimeter

June 2019 Woodbury Fire

  • July 2019 and September 2019


  • 7 measurements at unburned site


  • 24 measurements at low severity


  • 20 measurements at moderate severity

September 23, 2019

23% unburned,

53% low severity,

24% moderate severity,

<1% high severity

Not Available

Not Available

Saturated Hydraulic Conductivity

  • Low Severity = 0.78
  • Moderate Severity = 0.61


Wetting Front

  • Low Severity = 0.7
  • Moderate Severity = 0.61
  • Median Hydraulic Conductivity (mm/hr)
    • Unburned = 18
    • Low burn = 14
    • Moderate burn = 11
  • Median Wetting Front (m)
    • Unburned = 0.1
    • Low burn = 0.07
    • Moderate burn = 0.03

High exposed bedrock, sandy loam

Sonoran Desertscrub, cactus, succulents, shrubs

Conversion for Sorptivity to Wetting front

h_f=S^2/(2K_s(\theta_s-\theta_r)

\theta_s=0.41

\theta_r=0.065

Measurements made at the top 1 cm of soil

McGuire, L.A., Rengers, F.K., Kean, J.W., Staley, D.M. and Mirus, B.B. (2018). Incorporating spatially heterogeneous infiltration capacity into hydrologic models with applications for simulating post-wildfire debris flow initiation. Hydrological Processes, 32(9), pp.1173–1187. doi:https://doi.org/10.1002/hyp.11458.

Santa Ana Mountains, California near town of Silverado

September 2014 Silverado fire

23 measurements made on November 12, 2014 and April 11, 2015

  • July 19, 2015
  • September 15, 2015
  • November 3, 2015
  • January 5, 2016
  • January 6, 2016

Moderate to high severity

Green and Ampt

Kinematic Wave

Not available


  • Saturated Hydraulic Conductivity (mm/hr)
    • Mean (geometric) = 21.3
    • Mean (arithmetic) = 37.4
    • Stdev = 52
    • Median = 19.1
  • Sorptivity (mm/hr^{0.5})
    • Mean (geometric) = 1.9
    • Mean (arithmetic) = 9.2
    • Stdev = 13.9
    • Median = 3.4
  • Wetting Front (extracted from Table 4 from Ebel et al,, 2022)
    • Mean (geometric) = 0.2
    • Mean (arithmetic) = 17.7
    • Stdev = 50.3
    • Median = 0.4


Fine sandy loam

California sagebrush and chaparral

Method for converting hydraulic conductivity field estimates to a single basin wide estimate

K_e(R,\mu,CV)=\mu[1+1/\tilde{R}]^{}^{-1/p}

\tilde{R}R/\mu (scaled rainfall, R = steady state rainfall)

p = \beta(\lambda)/(cv^m)

m = 0.85

\beta=5\lambda^{-0.29}

\lambda = values of 4 or 6 have been suggested (correlated fields)

Measurements made at the top 1 cm of soil

Tang, H., McGuire, L.A., Rengers, F.K., Kean, J.W., Staley, D.M. and Smith, J.B. (2019). Evolution of Debris‐Flow Initiation Mechanisms and Sediment Sources During a Sequence of Postwildfire Rainstorms. Journal of Geophysical Research: Earth Surface, 124(6), pp.1572–1595. doi:https://doi.org/10.1029/2018jf004837.

San Gabriel Mountains, California


Las Lomas Debris basin

Summer of 2016 Fish Fire

  • 61 measurements made on September - December


  • 28 measurements made on January 2017
  • December 16, 2016
  • February 18, 2017

Moderate to High Severity

Green and Ampt

2-D nonlinear Shallow Water Equation coupled with a set of advection equations

Not available

  • Saturated Hydraulic Conductivity (mm/hr)
    • Mean (geometric) = 18.2
    • Mean (arithmetic) = 31.4
    • Stdev = 48
    • Median = 17.2
    • Range = 0.5 - 20
  • Wetting Front (m)
    • Mean (geometric) = 4.1
    • Mean (arithmetic) = 13.3
    • Stdev = 18.5
    • Median = 6.0
    • Range = 0.001 - 0.1
  • Sorptivity (mm/hr^{0.5})
    • Mean (geometric) = 7.8
    • Mean (arithmetic) = 12.3
    • Stdev = 11.5
    • Median = 8.6
  • Initial \theta = 0.05 (Literature value)
  • \theta_s=0.4 (Literature value 

Table 1 of report


Fine Sandy Loam

Not mentioned

  • Study area contained dry ravel deposits
  • Measurements made using Decagon mini disk portable tension infiltrometer at top 1 cm of soil
  • Debris flow initiation appears closely related to 15 minute intensity threshold
  • Both flow and raindrop driven sediment transport substantially contribute to sediment supply but flow driven processes critical for debris flow initiation
  • Mean (arithmetic and geometric), Stdev, and median values obtained from Table 4 of Ebel et al.,2020

Ebel, Brian A., and John A. Moody. "Synthesis of Soil-hydraulic Properties ad Infiltration Timescales in Wildfire-affected Soils." Hydrological Processes, no.2, Wiley, Nov. 2016, pp. 324-40. doi:10.1002/hyp.10998

Multiple locations within Western U.S and Australia

Multiple fires analyzed

Multiple measurements analyzed

Not available

Not available

Not available

Not available

Saturated Hydraulic Conductivity

  • Mean (geometric) = 0.79
  • Mean (arithmetic) = 0.31

Sorptivity

  • Mean (geometric) = 0.12
  • Mean (arithmetic) = 0.13

Wetting Front

  • Mean (geometric) = 0.02
  • Mean (arithmetic) = 0.03

 \theta_s

  • Mean (geometric) = 1.08
  • Mean (arithmetic) = 1.05


Saturated Hydraulic Conductivity (mm/hr)

  • Mean (geometric) = 51.6
  • Stdev (geometric) = 2.59
  • Coefficient of Variation (geometric) = 0.05
  • Mean (arithmetic) = 78.2
  • Stdev (arithmetic) = 82.5
  • Coefficient of Variation (arithmetic) = 1.05

Sorptivity (mm/hr^{0.5})

  • Mean (geometric) = 5.93
  • Stdev (geometric) = 12.9
  • Coefficient of Variation (geometric) = 2.18
  • Mean (arithmetic) = 11
  • Stdev (arithmetic) = 8.4
  • Coefficient of Variation (arithmetic) = 0.76

Wetting Front (mm)

  • Mean (geometric) = 1.01
  • Stdev (geometric) = 10.8
  • Coefficient of Variation (geometric) = 10.7
  • Mean (arithmetic) = 3.98
  • Stdev (arithmetic) = 4.37
  • Coefficient of Variation (arithmetic) = 1.1

 \theta_s

  • Mean (geometric) = 0.43
  • Stdev (geometric) = 1.03
  • Coefficient of Variation (geometric) = 2.39
  • Mean (arithmetic) = 0.43
  • Stdev (arithmetic) = 0.01
  • Coefficient of Variation (arithmetic) = 0.03


Not available

Not available

    • Study is a meta-analysis of 12 scientific papers with a total of 43 entries
    • Various soil textures and hydraulic property measurement methods were included together when averaging
    • S^2/K_{fs} is a soil hydraulic metric that indicates the relative magnitude of process dominance between capillary forces and gravity forces. Table 4 of the article provides values for burned, unburned, and ash soils
    • Study also analyzed soil hydraulic properties of ash and provides values in Table 4 of the article.
    • T_{grav} is a soil hydraulic metric that corresponds to the time when contributions of gravity forces are equal to the contributions of capillary forces. Table 4 of the article provides values for burned, unburned, and ash soils
    • Study did not control for burn severity, vegetation type, and soil textures.
    • Recommended setting wetting front values close to zero for burned soils that have low Sorptivity. 


Covington, W.W.; Sackett, S.S. 1990. Fire effects on ponderosa pine soils and their management implications. In: Krammes, J. S., tech. coord. Effects of fire management of southwestern natural resources. Gen. Tech. Rep. RM-GTR-191. Fort Collins, CO: U.S. Department of Agriculture, Forest Service, Rocky Mountain Forest and Range Experiment Station. p. 105-111.

Southwestern United States

Not available

Not available

Not available

Not available

Not available

Not available

  • Infiltration rate (Constant rate) = 0.36
  • Infiltration rate (Constant Rate, cm/hr): 2.5

Ponderosa Pine Forests

Not available

  • This study synthesizes information from multiple studies regarding the effects of fire on soil nutrient in southwestern ponderosa pine.
  • Runoff efficiency increases from 0.8 percent for unburned to 3.6 percent from areas severely burned.  Peak flows almost 400 times greater from severely burned areas.  This is likely because there is a reduction in vegetation and forest floor cover and to the formation of hydrophobic layers in the soils.