1. Evaluating the Quality of a Wildfire Defensible Space with Airborne LiDAR and GIS Jason Harshman GEOG 596A Capstone Proposal August 2015 1

2. Presentation Outline Background Project Goals Study Area Methodology Initial Results Future Plans 2 CAL FIRE

3. Background Prolonged drought in California has greatly increased wildfire risk Year-round wildfire season for much of California 11,000 structures lost to wildfires between 2003-2013 in California Over $30 million in damages in 2013 CAL FIRE annual budget over $200 million Wildfire near a San Marcos, CA home, May 2014 (Anthony Carrasco/San Diego Union-Tribune) Wildfire near a San Marcos, CA home, May 2014 (Sean M Haffey/San Diego Union-Tribune) 3

4. What is a defensible space? Prevent structure ignition Requires vegetation maintenance surrounding a structure 100 feet from a structure’s edge May extend beyond 100 feet Requirements can vary between different jurisdictions Split into 2 zones Illustration of a defensible space (CAL FIRE). 4

5. Defensible Space 0 to 30 feet (Zone A) “Free and Clear” Remove tree canopy overlapping structure Remove highly flammable vegetation 30 to 100 feet (Zone B) Reduce vegetation density Reduce ladder fuels Requirements vary depending on slope Illustration of Zone B requirements (CAL FIRE). 5

6. Project Goals Analyze the quality of a structure’s defensible space Quality equates to how well a structure’s defensible space follows defensible space regulations Use LiDAR data to map vegetation and terrain surrounding structures Develop a general methodology that can be applied to other locations 6

7. Project Location Sonoma County, CA 77% of county wildfire responsibility is CAL FIRE 20% is rated “Very High” for wildfire risk Regional location of Sonoma County, CAWildfire responsibility areas in Sonoma County, California 7

8. Locate a Study Area Identify a test location for analysis of a small group of structures o CAL FIRE responsibility area o 1-mile of the last 10 years of fires o “Very High” wildfire hazard areas o “Maximum” wildfire threat areas o Remove conservation/sensitive land and public land o Majority conifer and shrub land cover o Area must have structures 8

9. Study Area Proposed Study AreaSample selection of structures 9

10. LiDAR Data Airborne LiDAR and Orthoimagery collected in late 2013 Currently largest coverage of public domain LiDAR data within California Classified point cloud of LiDAR (http://sonomavegmap.org)http://sonomavegmap.org Structure footprints polygons derived from the LiDAR also available SourceSonoma County Vegetation Mapping and LiDAR Program (http://sonomavegmap.org/) Collected byWatershed Sciences, Inc. (WSI) Altitude900 AGL Laser Pulse Rate105,000 Hz Field of View30° Average Point Density2.88 p/m 2 Horizontal AccuracyNot provided Vertical Accuracy~6 cm LAS ClassificationsUnused (0), Unclassified (1), Ground (2), High Vegetation (5), Buildings (6), Noise (7), Water (9), Excluded (11) LAS Format1.2 10

11. Methodology Overview Create several surface datasets from the LiDAR Separate analysis for Zone A and Zone B Average results from Zone A and B into final score 11

12. Surface Datasets Create several surface datasets from the LiDAR DatasetAcronymResolutionFunction Data TypeInterpolation MethodSource Digital Elevation ModelDEM2 Feet Ground elevation surfaceGrid Natural Neighbors Triangulation Ground classified points, all returns Digital Surface ModelDSM2 Feet Terrain elevation surfaceGrid Natural Neighbors TriangulationFirst return points Canopy Height ModelCHM2 Feet Relative height from the groundGridN/ADSM-DEM SlopeN/A2 Feet Slope of ground surfaceGridN/ADEM Tree Canopy Surface ModelCSM2 Feet Canopy elevation surfaceGridSimple High vegetation classified points, first return Building Surface ModelBSM2 Feet Building elevation surfaceGridSimple Building classified points, all returns 12

13. Zone A Calculate amount of vegetation coverage within Zone A Zone A 30 feet Get count within structure footprints Calculate % of structure with overlap Zone A Value Calculate canopy overlap of structures BSM - CSM Reclassify positive values to 1 Get CSM count within Zone A Calculate % of CSM in Zone A Calculate canopy coverage within Zone A Average values 13 Determine if tree canopy overlaps structure footprint

14. Zone B Determine if distance between tree canopy is sufficient Zone B 30-100 feet Reclassify slope to 1, 2, 3 Create individual tree data with FUSION Plot locations in GIS Buffer based max crown widths Euclidean Distance of crowns Reclass distances of 10, 20, 30 ft to 1, 2, 3 Distance Reclass minus Slope Reclass 14

15. Zone B 15 Slope % ReclassTree Distance Reclass 1 (10 feet)2 (20 Feet)3 (30 Feet) 1 (0-20%) 012 2 (20-40%) 01 3 (40%+) -20 Slope Reclass - Distance Reclass matrix

16. Zone A + Zone B Average Scores together Scores closer to 0 suggest a better quality defensible space 16 0.01.0 High QualityPoor Quality

17. Zone A Initial Results Values range from 0.026 to 0.528 Lower value = higher quality of defensible space 17

18. Zone A Initial Results Lowest Zone A scoreLowest Zone B score 18

19. Zone B 19 Zone AZone B Poor quality Zone B Identify vegetation coverage that exceed minimum requirements Zone A Zone B High quality Zone B

20. Discussion 20 Validity of overall methodology Zone A initial results promising Need quality LiDAR for quality surface datasets Surface datasets key to analysis Justin Sullivan / Getty Images

21. Future Plans Refine methodology Scale-up analysis Diversify landscape types Analysis of other location(s) Build a tool or set of tools? 21 CAL FIRE

22. Timeline 22 August Refine Methodology ID Other Locations & Gather Data Submit Abstract AAG Annual Meeting Perform Analysis OctoberJanuaryMarch 20162015 May 596B Submit Write-up

23. References CAL FIRE. (2013). Wildfire activity statistics. Sacramento, CA: California Department of Forestry and Fire Protection. Retrieved from http://www.fire.ca.gov/downloads/redbooks/2013Redbook/2013_Redbook_Final.pdf http://www.fire.ca.gov/downloads/redbooks/2013Redbook/2013_Redbook_Final.pdf CAL FIRE. (2015a). Defensible space and hardening your home Retrieved from http://www.readyforwildfire.org/docs/files/CALFIRE_Ready_Brochure.pdf http://www.readyforwildfire.org/docs/files/CALFIRE_Ready_Brochure.pdf CAL FIRE. (2015b). Emergency fund fire suppression expenditures. Sacramento, California: California Department of Forestry and Fire Protection. Retrieved from http://www.fire.ca.gov/fire_protection/downloads/SuppressionCostsOnepage.pdfhttp://www.fire.ca.gov/fire_protection/downloads/SuppressionCostsOnepage.pdf Amy Hubbard. (2014, September). California burns through $209-million wildfire budget, taps $70 million more. Los Angeles TImes Retrieved from http://www.latimes.com/local/lanow/la-me-ln-california-exhausts-budget-wildfires-20140930-story.htmlhttp://www.latimes.com/local/lanow/la-me-ln-california-exhausts-budget-wildfires-20140930-story.html San Diego Union-Tribune. (2014). Day 2: San diego county fires. Retrieved from http://www.sandiegouniontribune.com/photos/galleries/2014/may/14/bernardo-fire-14-contained/ http://www.sandiegouniontribune.com/photos/galleries/2014/may/14/bernardo-fire-14-contained/ Alexandra D. Syphard, Teresa J. Brennan, & Jon E. Keeley. (2014). The role of defensible space for residential structure protection during wildfires. International Journal of Wildland Fire,, 1165-1175. doi:10.1071/WF13158 Philip E. Dennison, Simon C. Brewer, James D. Arnold, & Max A. Moritz. (2014). Large wildfire trends in the western united states, 1984–2011. Geophysical Research Letters, 41, 2928-2933. doi:10.1002/2014GL059576 Susan M. Stein, Sara J. Comas, James P. Menakis, Mary A. Carr, Susan I. Stewart, Helene Cleveland, Lincoln Bramwell and Volker C. Radeloff. (2013). Wildfire, wildlands, and people: Understanding and preparing for wildfire in the wildland-urban interface. (). Fort Collins, CO: U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station. Robert J. McGaughey. (2014). FUSION/LDV: Software for LIDAR data analysis and visualization Retrieved from http://forsys.cfr.washington.edu/fusion/FUSION_manual.pdf US Forest Service.Smokey bear. Retrieved from http://www.smokeybear.com/design-resources.asp 23

24. Acknowledgements Doug Miller 24

25. Questions? 25