8.1 Hazard and Risk Assessment

Mark Twain is a rapidly growing community that is located on the north side of Dayton Valley and to the north of US Highway 50 (see Figure 8-1). The valley is bordered on the north by the Virginia Range and on the south by the Pine Nut Range. The population estimate for the Mark Twain community is believed to have been included with Dayton in the 2000 census. (Dayton was estimated at 5,907 by the US Census Bureau, 2000).

In the Mark Twain community, 344 urban-interface residences were evaluated during the assessment. The risk/hazard assessment resulted in classifying the Mark Twain Community in the Moderate Hazard category (55 points). The moderate community hazard rating is attributed primarily to homes lacking visible addresses and limited emergency access on narrow dirt roads. The specific findings for each of the wildland fire assessment parameters are reported below. The community wildfire hazard score sheet is provided at the end of this section.

8.1.1 Community Design

The urban interface condition in Mark Twain can be described as both intermix and classic interface. Newer subdivisions have been built with a clear line of demarcation between the wildland fuels and the residences. However, homes built on larger lots often have continuous expanses of wildland fuels between structures. Lot sizes vary throughout Mark Twain. Approximately half of the lots are less than one acre in size, and half are in the one to 10 acre size range. Structure spacing in the community varies according to lot size.

Roads: The primary access route in Mark Twain is US Highway 50, which is a paved highway greater than 24 feet wide. Other primary roads include Six Mile Canyon (paved) and Rainbow Road (dirt), which are both greater than 24 feet wide allowing adequate room for fire suppression equipment to maneuver. Most of the secondary roads in the community are dirt roads less than 24 feet wide.

Signage: Most streets in the Mark Twain community have standard metal street signs that are highly visible and easy to read. Street signage throughout Mark Twain will assist fire suppression personnel in locating streets. Approximately one-fourth of residential addresses are not easily visible from residential streets. Some residences would be difficult to locate during poor visibility conditions that may exist during a wildland fire.

Utilities: The utilities that serve Mark Twain are a combination of above ground and below ground power lines, with larger lots generally served by propane and above ground power lines. Newer subdivisions in the area are served by below ground power lines. In general, utilities have adequately maintained right-of-ways and pose only a low ignition risk to the community.

8.1.2 Construction Materials

A majority of the homes observed in the interface area were built with fire resistant siding materials and had fire resistant roof materials such as composition shingles, metal, or tile roofing. Less than one-fourth of the homes observed had unenclosed balconies, porches, decks or other architectural features that can create drafty areas where sparks and embers can be trapped, smolder, and ignite, rapidly spreading fire to the home.

8.1.3 Defensible Space

Approximately three-fourths of the homes had landscaping that would meet the defensible space landscape requirement to protect the home from damage or minimize loss during a wildfire.

8.1.4 Suppression Capabilities

Wildfire Protection Resources

The Central Lyon County Fire Protection District provides wildfire protection. Refer to Section 4.2 for more information on equipment and resource availability. Some fire suppression equipment is stationed in the Mark Twain Volunteer Fire Department building, but there is no longer an active VFD in the Mark Twain community at this time. The fire station location is shown in Figure 8-1.

Water Sources and Infrastructure

Water availability for fire suppression in the Mark Twain community includes:

• Two community wells with storage tanks 179,000 gallons and 450,000 gallons. The community is in the process of acquiring a third tank with a capacity of two-million gallons
• 500 gpm hydrants within 500 feet of structures in the new developments. Community lots larger than one-acre have no hydrants nearby.

The community water system operates on electrical pumps. There is no backup emergency generator to run the pumps in case of a power failure.

8.1.5 Factors Affecting Fire Behavior

The fuel type around Mark Twain was comprised of a shrub layer of sagebrush, rabbitbrush, spiny hopsage, and littleleaf horsebrush with a grass understory of bottlebrush squirreltail, Indian ricegrass, and cheatgrass. Shrub density was sparse to moderately spaced. Shrubs were generally one to two feet in height on upper elevations and three to four feet in height on the valley bottom. The fuel load around Mark Twain was estimated at one to two tons per acre and considered a moderate fuel hazard.

Topography in the Mark Twain area is generally flat with slopes less than five percent. Steeper mountains and foothills lie directly north of the community.

8.1.6 Fire Behavior Worst-case Scenario

The worst-case fire behavior scenario would likely occur on a windy, low humidity summer afternoon in a normal to above normal precipitation year with high cheatgrass production. A lightning ignition west of the community could spread rapidly toward the community by west or southwest winds.

8.1.7 Ignition Risk Assessment

There is a moderate potential for fire ignition to occur in the vicinity of the Mark Twain community due to lightning associated with summer afternoon thunderstorms.

8.2 Risk and Hazard Reduction Recommendations, Roles, and Responsibilities

The responsibility to keep a community fire safe falls not only on the local fire protection district but also on the residents of the community, businesses, and local governments. The recommendations for Mark Twain focus primarily on additional efforts that can be taken by community members and public agencies to increase wildfire safety through reduction of hazardous fuels. Other recommendations pertain to community coordination and public education efforts that could be undertaken to promote fire safety in Mark Twain. The recommendations are detailed below and summarized in Table 8-1.

8.2.1 Defensible Space Treatments

The density and type of fuel around a home affects the potential fire exposure levels to the home. The goals of defensible space are to reduce the chances of a wildfire spreading onto adjacent property and igniting homes, and to reduce the risk of loss of property from wildfire. General guidelines for creating defensible space around residences and structures in the community are given below and are described in detail in Appendix E.

Property Owner Responsibilities

• Remove, reduce, and replace vegetation to create defensible space around homes according to the guidelines in Appendix E. 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.
• Immediately dispose of cleared vegetation when implementing defensible space treatments. This material dries quickly and poses a fire hazard if left on site.
• Maintain defensible space as needed to keep the space lean, clean, and green.
• Store firewood a minimum distance of 30 feet from structures.
• Mow or remove brush growing against wood fences in the community.
• Maintain areas under wood decks and porches free of weeds and other flammable debris. Install screens around unenclosed overhangs where possible.
• Clear all vegetation and combustible materials around propane tanks for a minimum distance of 10 feet.

8.2.2 Community Coordination

Coordination among local, state, and federal fire suppression agencies is important in the day-to-day fire prevention activities and becomes critical in the event of a wildland fire. During a wildfire event, firefighters from other communities and states may be dispatched to protect areas they have never been before. This is particularly true in areas that have limited fire suppression resources and will most likely depend on outside assistance in the event of a catastrophic wildland fire. The following recommendations should be implemented in Mark Twain to promote agency and community coordination.

Property Owner Responsibilities

• Form a local chapter of the Nevada Fire Safe Council. The Nevada Fire Safe Council facilitates solutions to reduce the loss of lives and property from the threat of wildfire in Nevada’s communities. Through the establishment of a local chapter, local communities will become part of a large network for sharing information and receive 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 will provide assistance and support to communities to complete fire safe plans, set priorities, educate and train community members, and promote success stories of its members. To form a local chapter, or for more information contact the:
  

  Nevada Fire Safe Council
  1187 Charles Drive
  Reno, Nevada 89509
  (775) 322-2413
  www.nvfsc.org

• Assure that residential addresses are visible from the road. Address characters should be at least four inches high, reflective, and composed of non-flammable material. Improving visibility of addresses will make it easier for those unfamiliar with the area to navigate under smoky conditions in the event of a wildland fire.

8.2.3 Public Education

Public education about how to become more fire safe is critical in communities that have rapidly growing populations, especially when many of the areas being developed are larger lots intermixed with wildland fuels. People moving into the area may be unfamiliar with fire-prone environments.

Central Lyon County Fire Protection District Responsibilities

• Distribute copies of the publication Living with Fire to all property owners. This publication is free of charge. Copies can be requested from the University of Nevada Cooperative Extension.
• Enforce or develop county laws, regulations, and ordinances that support implementation and maintenance of defensible space and address fuel reduction responsibilities for absentee homeowners and vacant lots.
• Contact the University of Nevada Cooperative Extension and the BLM Carson City Field Office for assistance with public education.

8.3 Summary of Recommendations

Table 8-1. Mark Twain Risk/Hazard Reduction Priority Recommendations

Responsible Party	Recommended Treatment	Recommendation Description
Property Owners	Defensible Space Treatments	Remove, reduce, and replace vegetation around homes according to the guidelines in Appendix E. Maintain defensible space as needed to keep the space lean, clean, and green.
	Community Coordination	Form a local chapter of the Nevada Fire Safe Council. Improve address visibility.
Central Lyon County Fire Protection District	Public Education	Distribute copies of the publication Living with Fire to all property owners. Enforce or develop county laws and ordinances for defensible space and fuel reduction responsibilities for absentee owners and vacant lots. Contact Nevada Cooperative Extension and the BLM for assistance with public education.

Figure 8-1 Fire History and Suppression Resources for the Community of Mark Twain small | large | x-large

Mark Twain Wildfire Hazard Rating Summary