24.1 Hazard and Risk Assessment

The Topaz Lake community is located in southern Douglas County along US Highway 395 and south of Holbrook Junction (junction with State Route 208), directly adjacent to the California state line. The community is situated on an east-facing slope directly above Topaz Lake. The community is bordered by National Forest lands to the north and west, and by the lake to the east. Approximately 120 homes were observed in the community during the assessment. The hazard assessment resulted in classifying Topaz Lake in the Moderate Hazard category (50 points). A summary of the factors that determine this hazard rating is included in Table 24-2. The primary conditions that affected the community hazard score for the Topaz Lake community were potentially hazardous fire behavior, limited community signage, and architectural features that increase structure ignition potential.

24.1.1 Community Design

The Topaz Lake interface area is characterized by the intermix wildland-urban interface condition. Structures are scattered throughout the wildland area with no clear line of demarcation between wildland fuels and residences in the community. In the intermix condition, parcels are generally greater than one acre (see Figure 24-1).

• Roads: US Highway 395 is the primary access route between the Topaz Lake community and other communities in Douglas County and California. Mark Twain Avenue, Sandy Bowers Avenue, and Topaz Park Road are the primary access roads for the community to access US Highway 395. The roads are paved, usually greater than 24 feet wide, and provide adequate access for fire suppression vehicles. Most of the secondary community roads had adequate turn around space for fire suppression equipment and approximately half of the community roads had a gradient greater than five percent.
• Signage: Street names were adequately identified with reflective lettering. Residential addresses were visible on a majority of the homes assessed. Clear and visible residential addresses are important to aid firefighting personnel in locating homes during low visibility conditions that occur during a wildland fire.
• Utilities: Overhead power lines are present within the community. Power line right-of-ways were not properly maintained, which increases the possibility of power lines sparking during windstorms and starting fires in nearby vegetation. Propane tanks throughout the community lack the minimum ten feet of vegetation clearance in many cases.

24.1.2 Construction Materials

Almost all of the homes assessed are built with fire resistant siding materials and non-combustible roofing materials, mainly composition type roofing. About 55 percent of the homes observed have unenclosed balconies, porches, decks or other architectural features that create drafts and provide areas where sparks and firebrands can be trapped, smolder, ignite, and rapidly spread fire to the home.

24.1.3 Defensible Space

Seventy-six percent of the homes observed in the interface have landscaping that would meet the minimum defensible space requirement to help protect the home from damage or loss during a wildfire.

24.1.4 Suppression Capabilities

Wildfire Protection Resources

Topaz Lake is provided wildland and structure fire protection by the East Fork Fire and Paramedic Districts Topaz Ranch Estates Volunteer Fire Department Station 4 (a combination career/volunteer station with two career members) and the Topaz Lake Volunteer Fire Department Station 5. At the time interviews were conducted for this report the Topaz Lake VFD reported 14 enrolled members who responded to 92 emergency calls in 2003 (East Fork Fire and Paramedic Districts website). See Tables 4-2 and 4-3 for more information on the typical fire suppression response for first-alarm wildland-urban interface fires in Douglas County. Appendix E lists the type and number of fire suppression vehicles located at each EFFPD and Douglas County VFD station.

Water Sources and Infrastructure

Water availability for fire suppression in Topaz Lake includes one 200,000-gallon tank in the community with an emergency generator for the pump that fills the tank. Hydrants are available near Topaz Lodge and the older sections of the community, but not for the entire community. Topaz Lake may be used for helicopter dip sites and as a drafting source.

24.1.5 Factors Affecting Fire Behavior

Vegetation, dead and down fuels, and topographic features contribute to the potential fire hazard around wildland-urban interface communities. The terrain within the Topaz Lake community is gently sloping with average slopes of ten percent; however, just west of the community slopes exceed thirty percent. The fuel hazard on the west side of the Topaz Lake community was considered high, estimated at three to ten tons per acre, depending upon tree density. Vegetation on the west side primarily consists of pinyon pine with big sagebrush, desert peach, Mormon tea, bitterbrush, and rabbitbrush occupying the spaces between trees. Cheatgrass and bottlebrush squirreltail were the dominant grasses.

On the north and east sides of the community, and within the community, the fuel hazard was considered moderate. The primary species present include big sagebrush, desert peach, Mormon tea, bitterbrush, and rabbitbrush; however, the shallow soils limit shrub heights and density. The fuel load was estimated to be one ton per acre in these areas.

Numerous fires have occurred within the vicinity of the community from both human and lightning causes. South of the community the Gate Complex Fire burned over 9,000 acres in 2002. The fuel hazard in the burned areas was considered low where cheatgrass was the dominant species. As the vegetation recovers from the fire, the fuel hazard will likely increase. A 307-acre fire and the sixteen-acre Wildoat Fire occurred northeast of the community in 1994. Numerous other fires have occurred south of the community between 1950 and 1975. The predominant wind direction is from the south especially in the late afternoon.

24.1.6 Fire Behavior Worst Case Scenario

The worst-case scenario for Topaz Lake would likely occur in the event of a lightning or human-caused ignition south of the community near the California state line. With south winds exceeding 25 miles per hour, a fire could rapidly spread through the vegetation and quickly threaten homes. Spot fires could expose numerous community structures to fire. The scenario would be worse if volunteer fire department resources were unavailable at the time of ignition. A minimum of thirty minutes (and more likely one hour) is needed for career-department resources to respond to an emergency in the community.

24.1.7 Ignition Risk Assessment

Topaz Lake has been rated with a high ignition risk, with dry lightning and power lines being the primary risks.

24.2 Risk and Hazard Reduction Recommendations

The Topaz Lake risk and hazard reduction recommendations focus on improving defensible space and promoting homeowner responsibilities. Other recommendations pertain to community coordination efforts that could be initiated to enhance the fire safe nature of Topaz Lake.

24.2.1 Defensible Space Treatments

Property Owner Recommendations

Defensible space treatments are an essential first line of defense for residential structures. Significantly reducing or removing vegetation within a prescribed distance from structures (30 feet to 200 feet depending upon slope and vegetative fuel type) reduces fire intensity and improves firefighter and homeowner chances for successfully defending a structure against an oncoming wildfire.

• Remove, reduce, and replace vegetation around homes according to the guidelines in Appendix D. This area should be kept:
  • Lean: There are only small amounts of flammable vegetation,
  • Clean: There is no accumulation of dead vegetation or other flammable debris,
  • Green: Existing plants are healthy and green during the fire season.
• Maintain the area beneath unenclosed wood decks and porches free of weeds and flammabledebris. Enclose these areas wherever possible.
• Store firewood a minimum distance of thirty feet from structures.
• Clear all vegetation and combustible materials for a minimum of ten feet around propane tanks.
• Install spark-arresting screens on chimneys.
• Cheatgrass or other annual grasses that have become dominant within the defensible space zone should be mowed or treated with an application of pre-emergent herbicide prior to seed set. Treatments may need to be repeated the following year to ensure that the seed bank of unwanted grasses has been depleted. Refer to Appendix D for recommended seed mixes and planting guidelines that can be used in conjunction with removal of this annual grass.
• Thin pinyon and juniper trees in the defensible space area such that tree canopies are spaced a minimum distance of thirty feet from any other trees, shrubs, or residential structures. Limb remaining pinyon and juniper trees within the defensible space area a minimum of four feet from the ground, or no more than one-third the height of the tree. Reduce the needle and cone duff from under the remaining trees to a depth no greater than one-inch.
• Irrigate all trees and shrubs in close proximity to structures to increase their fire resiliency, especially during drought conditions.
• Immediately remove cleared vegetation to an approved disposal site when implementing defensible space treatments. This material dries quickly and presents a fire hazard if left on site.
• Maintain this defensible space as needed to keep the space lean, clean, and green.

24.2.2 Fuel Reduction Treatments

Fuel reduction treatments are applied on a larger scale than defensible space treatments. By permanently changing the fuel structure over large blocks of land to one of a lower volume or reduced flammability (a fuel reduction treatment), the expected result in the event of a catastrophic wildfire would be one of reduced capacity for uncontrolled spread through the treatment area.

Property Owner Recommendations

• Reduce vegetative fuels for a distance of ten feet on both sides of private driveways longer than 200 feet. Remove highly flammable shrubs and pinyon/juniper trees and replace with fire-resistant species such as crested wheatgrass, lawn, or a pre-suppression seed mix. Appropriate seed mixtures and seeding specifications are provided in Appendix D.
• On all private lots with pinyon pine trees, remove ladder fuels (shrubs and grasses) within ten feet of all tree drip lines. Limb pinyon trees a minimum of four feet up from the ground or no more than one-third the height of the trees.
• Coordinate with EFFPD to construct fuel reduction on all private parcels with pinyon pine trees.

East Fork Fire and Paramedic Districts Recommendation

• Coordinate with property owners to construct fuel reduction on private parcels, especially those with a pinyon pine tree canopy.

Douglas County Roads Department Recommendation

• Remove pinyon/juniper trees, shrubs, and weeds for a distance of 25 feet on each side of roads in the community. For an additional 25 feet on each side of the road, reduce pinyon and juniper tree density to less than ten trees per acre.

Utility Company Recommendation

• Remove pinyon pine and shrubs within fifteen feet of power poles and power line throughout the Topaz Lake community.

24.2.3 Community Coordination

Many of the most effective activities aimed at reducing the threat of wildfire for the Topaz Lake community require that individual property owners coordinate with each other and with local fire authorities. Defensible space, for example, is more effective in small communities when applied uniformly throughout entire neighborhoods. Public education and awareness, neighbors helping neighbors, and proactive individuals setting examples for others to follow are just a few of the approaches that will be necessary to meet the fire safe goals in the community. Disposal of biomass generated from defensible space and fuel reduction treatments can sometimes be most efficiently handled through community programs.

Property Owner Recommendations

• Assure addresses are visible from the road on all homes within the community. Address characters should be readily visible from the road, at least four inches tall, and reflective.
• Form a local chapter of the Nevada Fire Safe Council. The Nevada Fire Safe Council proposes to work on solutions that reduce the risk of loss of lives and property from wildfires in Nevada’s communities. Through establishment of a local Chapter, communities become part of a large information-sharing network that receives notifications of programs and funding opportunities for fire mitigation projects such as those listed in this report. The Nevada Fire Safe Council will accept and manage grants and contracts on the Chapter’s behalf through its non-profit status. The Nevada Fire Safe Council provides assistance and support to communities to complete fire safe plans, set priorities, educate and train community members, and promote success stories of its members. For more information on forming a chapter, contact:
  

  Nevada Fire Safe Council
  1187 Charles Drive
  Reno, Nevada 89509
  www.nvfsc.org

East Fork Fire and Paramedic Districts Recommendation

• Distribute copies of the publication “Living With Fire” to all property owners who live in Topaz Lake. This publication is free of charge. Copies can be requested from the University of Nevada Cooperative Extension.

24.3 Summary of Recommendations

Table 24-1. Topaz Lake Priority Recommendations to Reduce Wildfire Risks and Hazards

Involved Party	Recommended Treatment	Recommendation Description
Property Owners	Defensible Space	Remove, reduce, and replace vegetation around homes according to the defensible space guidelines in Appendix D.
	Fuels Reduction	Reduce vegetative fuels for a distance of ten feet on both sides of private driveways longer than 200 feet. On all private lots with pinyon pine trees, remove ladder fuels (shrubs and grasses) within ten feet of all tree drip lines. Limb pinyon trees up a minimum of four feet or no more than one-third the height of the trees. Coordinate with EFFPD to implement fuel reduction on all private parcels with pinyon trees.
	Community Coordination	Assure addresses are visible from the road. Form a local chapter of the Nevada Fire Safe Council.
Douglas County	Fuels Reduction	Remove pinyon/juniper trees, shrubs, and weeds for a distance of 25 feet on each side of roads in the community. For an additional 25 feet on each side of the road, reduce pinyon and juniper tree density to less than ten trees per acre.
Utility Company	Fuels Reduction	Remove trees or trim any branches within fifteen feet of either side of power lines and poles throughout the Topaz Lake community.
East Fork Fire and Paramedic Districts	Fuels Reduction	Coordinate with property owners to implement fuel reduction on private parcels, especially all pinyon pine tree areas throughout the community.
	Community Coordination	Distribute copies of the publication “Living With Fire” to all property owners.

Table 24-2 Topaz Lake Wildfire Hazard Rating Summary

Figure 24-1 Topaz Lake Fire History and Suppression Resources small | large | x-large