evaluating increased erosion potential due to wildfires
DESCRIPTION
Evaluating Increased Erosion Potential due to Wildfires. Brian Drake CE394K – Fall 2005 Term Project Presentation. Study Area. Cedar Wildfire. Duration: 10/25/03 – 11/3/03 Size = 280,000 acres 2,232 homes destroyed 15 human deaths Suppression Cost: >$31 Mil. - PowerPoint PPT PresentationTRANSCRIPT
![Page 1: Evaluating Increased Erosion Potential due to Wildfires](https://reader035.vdocument.in/reader035/viewer/2022062814/56816830550346895dddd80a/html5/thumbnails/1.jpg)
Evaluating Increased Erosion Potential due to Wildfires
Brian DrakeCE394K – Fall 2005
Term Project Presentation
![Page 2: Evaluating Increased Erosion Potential due to Wildfires](https://reader035.vdocument.in/reader035/viewer/2022062814/56816830550346895dddd80a/html5/thumbnails/2.jpg)
Study Area
![Page 3: Evaluating Increased Erosion Potential due to Wildfires](https://reader035.vdocument.in/reader035/viewer/2022062814/56816830550346895dddd80a/html5/thumbnails/3.jpg)
Cedar Wildfire
• Duration: 10/25/03 – 11/3/03• Size = 280,000 acres• 2,232 homes destroyed• 15 human deaths• Suppression Cost: >$31 Mil
![Page 4: Evaluating Increased Erosion Potential due to Wildfires](https://reader035.vdocument.in/reader035/viewer/2022062814/56816830550346895dddd80a/html5/thumbnails/4.jpg)
Major Factors Affecting Soil Losses
• Vegetative Cover• Soil Characteristics• Topography• Intensity of Storms
![Page 5: Evaluating Increased Erosion Potential due to Wildfires](https://reader035.vdocument.in/reader035/viewer/2022062814/56816830550346895dddd80a/html5/thumbnails/5.jpg)
Modeling Erosion
• USDA Universal Soil Loss Equation (USLE)
• A = R∙K∙LS∙C∙P– A = Soil loss per unit area– R = Rainfall-Runoff Erosivity– K = Soil Erodibility– LS = Slope Length/Steepness Factor– C = Land Cover Factor– P = Conservation Practice Factor
![Page 6: Evaluating Increased Erosion Potential due to Wildfires](https://reader035.vdocument.in/reader035/viewer/2022062814/56816830550346895dddd80a/html5/thumbnails/6.jpg)
Rainfall-Runoff Erosivity (R)
• Reflects rainfall intensity and storm energy
![Page 7: Evaluating Increased Erosion Potential due to Wildfires](https://reader035.vdocument.in/reader035/viewer/2022062814/56816830550346895dddd80a/html5/thumbnails/7.jpg)
Soil Erodibility (K)
• Represents susceptibility of soil to erosion
Legend0.100000002 - 0.136666669
0.136666669 - 0.173333336
0.173333336 - 0.210000003
0.210000003 - 0.246666671
0.246666671 - 0.283333338
0.283333338 - 0.320000005
0.320000005 - 0.356666673
0.356666673 - 0.393333340
0.393333340 - 0.430000007
![Page 8: Evaluating Increased Erosion Potential due to Wildfires](https://reader035.vdocument.in/reader035/viewer/2022062814/56816830550346895dddd80a/html5/thumbnails/8.jpg)
Slope Length/Steepness (LS)
LS = (a/22.13)0.4 (s/0.0896)1.3
DEM
![Page 9: Evaluating Increased Erosion Potential due to Wildfires](https://reader035.vdocument.in/reader035/viewer/2022062814/56816830550346895dddd80a/html5/thumbnails/9.jpg)
Land Cover Factor (C)• Ratio of soil loss based on vegetative cover
![Page 10: Evaluating Increased Erosion Potential due to Wildfires](https://reader035.vdocument.in/reader035/viewer/2022062814/56816830550346895dddd80a/html5/thumbnails/10.jpg)
Conservation Practice Factor (P)
• Reflects impact of erosion-reduction practices
![Page 11: Evaluating Increased Erosion Potential due to Wildfires](https://reader035.vdocument.in/reader035/viewer/2022062814/56816830550346895dddd80a/html5/thumbnails/11.jpg)
Total Sediment Potential (A)
Aave = 30.7 ton/acre/yr
Aave = 1,295 ton/acre/yr
![Page 12: Evaluating Increased Erosion Potential due to Wildfires](https://reader035.vdocument.in/reader035/viewer/2022062814/56816830550346895dddd80a/html5/thumbnails/12.jpg)
Remaining Tasks
• Adjustments to current pre-fire calculation– Check for unit consistency– Search for more representative R-Factor– Ensure that LS value is accurate
• Modify factors to model post-fire conditions– Increase C-Factor
![Page 13: Evaluating Increased Erosion Potential due to Wildfires](https://reader035.vdocument.in/reader035/viewer/2022062814/56816830550346895dddd80a/html5/thumbnails/13.jpg)
Resources
• DEM: http://seamless.usgs.gov/
• NHD: http://nhd.usgs.gov/data.html
• USDA Soils: http://www.ncgc.nrcs.usda.gov/products/datasets/statsgo/
• Fire Info: http://map.sdsu.edu/fireweb/
![Page 14: Evaluating Increased Erosion Potential due to Wildfires](https://reader035.vdocument.in/reader035/viewer/2022062814/56816830550346895dddd80a/html5/thumbnails/14.jpg)
Questions?