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Lost Creek Wildfire Assessment

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A risk assessment for wildfires affecting Lost Creek.

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Lost Creek Wildfire Assessment

  1. 1. Lost Creek Wildfire AssessmentLost Creek Wildfire Assessment Paul Schumann Lost Creek Civic Organization September 28, 2016
  2. 2. September 28, 2016 Lost Creek Civic Organization 2 Topics Executive Summary Research Analysis Conclusions Maps Appendix
  3. 3. September 28, 2016 Lost Creek Civic Organization 3 Executive Summary The purposes of this research was to: ● Give homeowners in Lost Creek whose property is adjacent a wildlands or natural area some information about the risk they have of wildfire spreading onto their property and potentially damaging their home ● Give homeowners in the WUI (wildlands urban interface) an idea about the defensibility of their property to a wildfire ● Suggest priorities for mitigation of the wildfire risk in the wildland areas adjacent to Lost Creek. ● Identify the owners of the wildlands whose property is a high priority risk of wildfire encroachment into Lost Creek residences. ● Provide an analysis that will become a key component in Lost Creek's Fire Adapted Communities Plan. The following are the conclusions reached: ● Lost Creek has a serious wildfire risk ● Homeowners in Lost Creek in the WUI have limited capability to protect their homes by themselves ● Because the City of Austin's Barton Creek Wilderness Area in our WUI is also covered by the Canyonlands Wildlife Preserve (BCP), there are severe limitations as to what can be done and when, this area should be planned first ● The combination of wildfire characteristics and homeowner land defensibility appears to provide a method to prioritize the areas of Lost Creek we need to focus on
  4. 4. September 28, 2016 Lost Creek Civic Organization 4 Research The purpose of this research was to give homeowners in Lost Creek whose property is adjacent a wildlands or natural area some information about the risk they have of wildfire spreading onto their property and potentially damaging their home and an idea about the defensibility of their property to a wildfire. The second purpose of this research was to suggest priorities for mitigation of the wildfire risk in the wildland areas adjacent to Lost Creek. The third purpose of this research was to identify the owners of the wildlands whose property is a high priority risk of wildfire encroachment into Lost Creek residences. This analysis will become a key component in Lost Creek's Fire Adapted Communities Plan. All the data used in this analysis came from three sources: City of Austin Development Map (http://www.austintexas.gov/GIS/DevelopmentWebMap/Viewer.aspx) This map requires Internet Explorer and Silverlight. The Purpose of the Planning and Zoning Department is to provide planning, preservation and design services to make Austin the most livable city in the country. The City of Austin is committed to improving the experience of residents, small businesses, developers and other stakeholders who need planning-related services. The Planning and Zoning Department (PAZ) has undergone an extensive process to lay the groundwork to making necessary changes for Austin's future. Texas Wildfire Risk Portal (https://www.texaswildfirerisk.com/) TxWRAP is the primary mechanism for the Texas A&M Forest Service to deploy risk information and create awareness about wildfire issues across the state. TxWRAP is comprised of a suite of applications tailored to support specific workflow and information requirements for the public, local community groups, government officials, professional hazard-mitigation planners, and wildland fire managers. Collectively these applications will provide the baseline information needed to support mitigation and prevention efforts across the state. This portal has computer models that generate data with 100 foot resolution on 22 variables in four categories: wildfire risks, wildfire behavior, landscape characteristics and historical wildfire occurrence.
  5. 5. September 28, 2016 Lost Creek Civic Organization 5 The complete report generated by the portal for Lost Creek and 3 mile circumference around Lost Creek is available at http://tinyurl.com/hcrnyut. To accomplish the purpose of this research, the analysis had to be at a street level customized to Lost Creek. Travis County Property Search (http://www.traviscad.org/property_search.html) To address the defensibility of homes in Lost Creek at the Wildlands – Urban Interface (WUI), the principles of Firewise (http://www.firewise.org/) were applied. Brush, grass and forest fires don’t have to be disasters. NFPA’s Firewise Communities Program encourages local solutions for safety by involving homeowners in taking individual responsibility for preparing their homes from the risk of wildfire. Firewise is a key component of Fire Adapted Communities – a collaborative approach that connects all those who play a role in wildfire education, planning and action with comprehensive resources to help reduce risk. The program is co-sponsored by the USDA Forest Service, the US Department of the Interior, and the National Association of State Foresters. To save lives and property from wildfire, NFPA's Firewise Communities program teaches people how to adapt to living with wildfire and encourages neighbors to work together and take action now to prevent losses. We all have a role to play in protecting ourselves and each other from the risk of wildfire. The concept of the home ignition zone was developed by USDA Forest Service fire scientist Jack Cohen in the late 1990s, following some breakthrough experimental research into how homes ignite due to the effects of radiant heat. For more than 15 years, NFPA’s wildfire safety recommendations have been shaped by this fire science and because of it, is able to provide actionable guidance for homeowners to help them prepare homes/home landscapes to resist wildfire. The primary goal for Firewise landscaping is fuel reduction — limiting the amount of flammable vegetation and materials surrounding the home and increasing the moisture content of remaining vegetation. The home itself and everything around it up to 100 – 200 feet is known as the ‘home ignition zone'. In areas across the country where the risk of wildfire is high, the home ignition zone extends up to 200 feet
  6. 6. September 28, 2016 Lost Creek Civic Organization 6 beyond the actual home structure. Within this 200 foot area, there are three zones: Zone 1 encircles the structure and all its attachments (wooden decks, fences, and boardwalks) for at least 30 feet on all sides. Note: the 30-foot number comes from the very minimum distance, on flat ground, that a wood wall can be separated from the radiant heat of large flames without igniting. In this area: ● Plants should be carefully spaced, low-growing and free of resins, oils and waxes that burn easily. ● Mow the lawn regularly. Prune trees up six to ten feet from the ground. ● Space conifer trees 30 feet between crowns. Trim back trees that overhang the house. ● Create a ‘fire-free’ area within five feet of the home, using non-flammable landscaping materials and/or high-moisture-content annuals and perennials. ● Remove dead vegetation from under deck and within 10 feet of house. ● Consider fire-resistant material for patio furniture, swing sets, etc. ● Remove firewood stacks and propane tanks; they should not be located in this zone. ● Water plants, trees and mulch regularly. ● Consider xeriscaping if you are affected by water-use restrictions. Zone 2 is 30 to 100 feet from the home, and plants in this zone should be low-growing, well irrigated and less flammable. In this area: ● Leave 30 feet between clusters of two to three trees, or 20 feet between individual trees. ● Encourage a mixture of deciduous and coniferous trees. ● Create ‘fuel breaks’, like driveways, gravel walkways and lawns. ● Prune trees up six to ten feet from the ground.
  7. 7. September 28, 2016 Lost Creek Civic Organization 7 Zone 3 is 100 to 200 feet from the home and this area should be thinned, although less space is required than in Zone 2. NOTE: Because of other factors such as topography, the recommended distances to mitigate for radiant heat exposure actually extend between 100 to 200 feet from the home – on a site-specific basis. In this area: ● Remove smaller conifers that are growing between taller trees. Remove heavy accumulation of woody debris. ● Reduce the density of tall trees so canopies are not touching. 0 30 ft 100 ft 200 ft This three zone ignition model was used to determine defensibility of the home depending upon the distance of the house from the WUI. If the homeowner could only apply zone 1 recommendations to his or her own property, then the defensibility was rated low because the homeowner is dependent upon the woodlands owner for complete defensibility. If the homeowner could apply all the recommendations for all three zones, he or she can adopt the best practices to lower the risk that a wildfire would damage their home. All property owners, regardless of the number of zones they can apply to their property, and even if their house not on an WUI, need to address the "little things" first: NFPA* advises property owners to start with the house and work their way out. Having a nonflammable roof covering and assembly adds an enormous safety measure. Keeping roofs and gutters clean and clear of leaves or needles is critical to minimizing ignition from embers. Flammable attachments (e.g., untreated wooden decks) * Home Ignition Zone Structure Assessment Guide in Appendix
  8. 8. September 28, 2016 Lost Creek Civic Organization 8 are very vulnerable to ignition and can carry fire to the main structure. Keep flat surfaces clear of debris. Clean out any leaves, needles or stored material that could burn from under decks, porches or eaves. During this high fire danger season, remove large potential heat sources such as piles of firewood, spare building materials, vehicles - anything that could catch embers or ignite by flames in the grass needs to be as far away from dwellings as possible. For reference purposes only I have named 9 zones in Lost Creek with WUI as shown in the graphic adjacent. These zones in combination with street names should help identify problem areas. The green areas in this map represent the Barton Creek Wilderness Area and are owned by the City of Austin, There is an additional overlay on this area called the Balcones Canyonlands Wildlife Preserve (next page). The Balcones Canyonlands Preserve (BCP) is not one single tract of land but a system of preserves that exists as a multi-agency conservation effort operating under a
  9. 9. September 28, 2016 Lost Creek Civic Organization 9 Lost Creek
  10. 10. September 28, 2016 Lost Creek Civic Organization 10 regional 10(a) permit issued under the Endangered Species Act by the U.S. Fish & Wildlife Service (USFW). The permit was issued jointly to the BCP's two managing partners, the City of Austin and Travis County, in 1996, though several other organizations own and manage land dedicated to the BCP. Ultimately, the goal is to set aside 30,428 acres in western Travis County as habitat for eight endangered species-two neotropical migratory songbirds and six karst invertebrates-and 27 species of concern. This overlay which covers all of Y Canyon and part of Barton Creek zones named in Lost Creek. This severely limits what and when any wildfire mitigation efforts can be done in the BCP. The ownership of the WUI land is shown in the adjacent graphic. The private land is owned by Hill County Golf Inc.(109602), Johnson Trust No. 1 (109610), and Dan Marshall II et al (109592). Travis County Property Search showed unknown owner for 816142. All the results are shown graphically in maps. These are shown full page for improved resolution. Private Lost Creek Limited District City of Austin Ownership of Land Unknown Travis County Trustee
  11. 11. September 28, 2016 Lost Creek Civic Organization 11 Analysis Wildfire parameters that apply to all of Lost Creek Several of the wildfire parameters apply to all of Lost Creek. These are shown in maps 1 – 5. ● Wildland Urban Interface (WUI): 0.5 to 3 homes/acre. Depicts where humans and their structures meet or intermix with wildland fuel ● WUI Response Index:Most Negative Impact. Represents a rating of the potential impact of a wildfire on values and assets ● Wildfire Threat: Moderate to high. Likelihood of a wildfire occurring or burning into an area ● Dozer Operability Rating: Significant operating limitations to inoperable in almost all of the WUI. This is the result of the homes being built on ridges with steep slopes behind them. The implication is that a wildfire would have to fought by hand. The map adjacent shows Lost Creek aerial view on which all the wildfire data is plotted.
  12. 12. September 28, 2016 Lost Creek Civic Organization 12 ● Surface Fuels*: FM9 HWD - Hardwood litter (fluffy), FM 8 – Closed timber litter (compact), and GS 2 – Moderate load, dry climate grass. Contains the parameters needed to compute surface fire behavior characteristics. * In the wildlands.
  13. 13. September 28, 2016 Lost Creek Civic Organization 13 Wildfire parameters that vary within Lost Creek Many of the wildfire parameters indicate differences within Lost Creek. These are shown in maps 6 – 9. ● Ignition Density: Low to Very High. Likelihood of a wildfire starting based on historical ignition patterns ● Fire Intensity: From low to high/very high. Quantifies the potential fire intensity for an area by orders of magnitude ● Rate of Spread: 5/10 chains per hour to 30/40 chains per hour* (5.5 to 44 feet per minute). Represents the speed with which a fire moves in a horizontal direction across the landscape ● Fire Type: Surface fire to canopy fire. Represents the potential fire type (surface or canopy) under the extreme percentile weather category * I chain is 66 feet so 5 chains per hour is 5.5 feet per minute Ignition Density
  14. 14. September 28, 2016 Lost Creek Civic Organization 14 Defensibility of homes Measured by how many of the three ignition zones specified in Firewise, the rating of homes on the WUI ranged from Low (red) to Medium (orange) to High (blue) (Map 10) Summary by Area The data on the maps are summarized in a table on the next page. The percentage numbers are representative of the scale of the legend on the maps: ● Ignition Density: 1 to 7, low to very high ● Fire Intensity: 1 to 5, very low to very high ● Defensibility: 1 to 3, Zone 1 only – all three zones For example an average ignition density in an area of 4.5 would be 64% of the scale.
  15. 15. September 28, 2016 Lost Creek Civic Organization 15 Area Ignition Density Fire Intensity Rate of Spread Fire type Defensibility of Homes Number of Homes Barton Creek 43% 90% 33 – 44 ft/min Canopy 59% 13 Barton Creek North 50% 90% 55 – 165 ft/min Canopy 100% 4 Barton Creek South 14% 88% 33 – 44 ft/min Canopy Some Surface 47% 15 Barton Creek SW 14% 90% 33 – 44 ft/min Canopy 33% 6 Barton Creek West 28% 80% 33 – 44 ft/min Canopy 33% 8 + condos Big Canyon 28% 88% 33 – 44 ft/min Canopy 44% 22 Country Club 28% 88% 55 – 165 ft/min Canopy 100% 21 Cypress Canyon 21% 90% 33 – 44 ft/min Canopy 54% 53 Indian Canyon 71% 90% 33 – 44 ft/min Canopy 50% 34 Marshal Ranch 100% 85% 33 – 44 ft/min Canopy Some Surface 37% 21 Sedgefield Canyon 43% 90% 33 – 44 ft/min Canopy Some Surface 50% 32 Y Canyon 93% 90% 33 – 44 ft/min Canopy Some Surface 45% 66 Y Canyon South 43% 90% 33 – 44 ft/min Canopy 64% 23
  16. 16. September 28, 2016 Lost Creek Civic Organization 16 The table on the following page displays the results based on ranking – what area's had the worst to best conditions. In order to compare all of the results, defensibility was changed to vulnerability so that the number 1 ranking was the least defensible. The page following the table shows the total score for each area of Lost Creek assuming all the parameters are weighted equally, i.e. each parameter is of equal importance. Individuals in the community might weigh the factors different. Using this scoring method, the top four rated areas are: 1. Y Canyon 2. Marshall Ranch* 3. Indian Canyon 4. Cypress Canyon * Marshall Ranch has been modified since these maps were created. The top of the ridge was bulldozed in preparation of development.
  17. 17. September 28, 2016 Lost Creek Civic Organization 17 Rank Ignition Density Fire Intensity Spread Rate Vulnerability Number of Homes 1 Marshall Ranch Barton Creek Barton Creek North Barton Creek SW Cypress Canyon Indian Canyon Sedgefield Canyon Y Canyon Y Canyon South Barton Creek North Country Club Barton Creek SW Barton Creek Y Canyon 2 Y Canyon * * Marshal Ranch Cypress Canyon 3 Indian Canyon Big Canyon Indian Canyon 4 Barton Creek North Y Canyon Sedgefield Canyon 5 Barton Creek Sedgefield Canyon Barton Creek South Y Canyon South * All the rest tied for 2nd
  18. 18. September 28, 2016 Lost Creek Civic Organization 18 BartonCreek BartonCreekNorth BartonCreekSouth BartonCreekSW BartonCreekWest BigCanyon CountryClub CypressCanyon IndianCanyon MarshalRanch SedgefieldCanyon YCanyon YCanyonSouth 0 0.5 1 1.5 2 2.5 3 3.5 4 Summary of Risks Number of Homes Vulnerability Rate of Spread Fire Intensity Ignition Density Area in Lost Creek TotalScore
  19. 19. September 28, 2016 Lost Creek Civic Organization 19 Conclusions The following are the conclusions reached: ● Lost Creek has a serious wildfire risk. Even though the overall risk of a wildfire is only moderate to high, the consequences of a wildfire due to a large WUI are extremely large. There are about 310 of the 1,250 homes in Lost Creek in the WUI. ● Homeowners in Lost Creek in the WUI have limited capability to protect their homes by themselves. On average, only about 50% of the protection required by Firewise can be implemented by the homeowners themselves. As a result, we are dependent on the adjacent property landowners to provide the full protection required. These land owners fall in three categories – City of Austin, Lost Creek Limited District and private. We only control the Limited District. ● While we are not in a drought period now, it can return quickly, so we must plan and act. ● Because the City of Austin's Barton Creek Wilderness Area in our WUI is also covered by the Canyonlands Wildlife Preserve (BCP), there are severe limitations as to what can be done and when, this WUI should be planned first. This will require a deep engagement with possibly the city, county, state and federal officials. Houses, that were established before the BCP and lives need to be protected as well as wildlife. ● The combination of wildfire characteristics and homeowner land defensibility appears to provide a method to prioritize the areas of Lost Creek we need to focus on. Given an equal weighting of the ranking of the characteristics, the following area priorities emerge with adjacent property owner: ➔ Y Canyon (City of Austin) ➔ Marshall Tract (Dan Marshal) ➔ Indian Canyon (LCLD) ➔ Cypress Canyon (LCLD) If the community decides it would like to weight the variables differently, I will accommodate that analysis.
  20. 20. September 28, 2016 Lost Creek Civic Organization 20 Maps 1. Lost Creek 2. WUI 3. WUI Response Index 4. Dozer Operability Rating 5. Surface Fuels 6. Ignition Density 7. Fire Intensity 8. Rate of Spread 9. Fire Type 10.Defensibility of Homes
  21. 21. September 28, 2016 Lost Creek Civic Organization 21 1. Lost Creek
  22. 22. September 28, 2016 Lost Creek Civic Organization 22 2. WUI
  23. 23. September 28, 2016 Lost Creek Civic Organization 23 3. WUI Response Index
  24. 24. September 28, 2016 Lost Creek Civic Organization 24 4. Dozer Operating Rating
  25. 25. September 28, 2016 Lost Creek Civic Organization 25 5. Surface Fuels
  26. 26. September 28, 2016 Lost Creek Civic Organization 26 6. Ignition Density
  27. 27. September 28, 2016 Lost Creek Civic Organization 27 7. Fire Intensity
  28. 28. September 28, 2016 Lost Creek Civic Organization 28 8. Rate of Spread
  29. 29. September 28, 2016 Lost Creek Civic Organization 29 9. Fire Type
  30. 30. September 28, 2016 Lost Creek Civic Organization 30 10. Defensibility of Homes Red – Low Orange – Medium Blue - High
  31. 31. September 28, 2016 Lost Creek Civic Organization 31 Appendix
  32. 32. September 28, 2016 Lost Creek Civic Organization 32 Paul Schumann President Lost Creek Civic Organization 3300 Bee Cave Road, Suite 650 #1152, Austin TX 78746 512.632.6586 info@lostcreekcivicorganization.org Www.lostcreekcivicorganization.org https://www.facebook.com/lostcreekcivicorganization/ @CivicOrg

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