Bitterroot Valley Wildfire Response Guide

The Responsibilities Homeowners Have When Living in the Wildland Urban Interface (WUI):

People live in Western Montana for many different reasons.  Some people live here for the solitude and tranquilty of the area and others for the great sense of community, spirit, and pride.  Still others choose to live here for the beauty of the mountains and the trees and to enjoy nature at its fullest.  Fire, too is a natural part of the ecosystem where we all choose to live and play.

Historically, wildfires burned as often as every 7 years in the lower elevation ponderosa pine/Douglas fir fuel types of the Bitterroot Valley. These are also the areas where many people have built and continue to build homes and this area is known as the Wildland Urban Interface (WUI) or the area where structures and other human development intermix with the undeveloped wildland fuels. As more people build in and near the WUI, the complexity of fighting wildfires for structure and wildland firefighters and the risk to them and the public continues to increase.  In addition to this higher risk, there is also a continued increase in the cost of fighting fires within these areas.

There are, however, measures responsible homeowners can take to minimize the threat that wildfires pose to their homes, their neighbors homes, to firefighters and to the public. These “Firewise” steps are described below and are designed to mitigate to some extent the risk of wildfires igniting structures. There are, however, no guaranteed “safe” techniques to provide to people who chose to live in the WUI. Living in the WUI involves accepting a measure of risk of loss due to wildfires.

The immediate area around a structure is known as the “home ignition zone” and is the area where most of the effort should be placed when addressing wildfire mitigation and survivability of a structure (see the figure below). The type and condition of the fuels and the topography where your home is built will determine how far from the structure one must treat fuels.  At a minimum, one should treat fuels for at least 30 feet from the structure, but this distance may need to be as much as 100-200 feet.   Fire requires three basic elements to exist; a heat source, fuel and oxygen.  Reducing hazardous fuels immediately around the home and using non-flammable materials for construction will reduce the potential for fire spread within the home ignition zone.

Pre Fuels Treatment (Photos by Bitterroot RC&D)

Post Fuels Treatment (Photos by Bitterroot RC&D)

Firewise construction of non-flammable materials is important to use in home construction and remodeling.   Homes and structures should have;

• roofing and siding made of non- flammable materials
• vents and other openings such as chimney flues screened with a metal mesh of 1/8” to ¼” to prevent flying embers from entering the area
• double-paned windows to protect against exposure to radiant heat
• decks which have been closed off or screened across the lower side
• wood piles, mulch or other materials moved away from the home

How fire behaves and reacts is based on three factors; fuels, topography and weather. If your home is already built, then the most easily mitigating factor is the fuels component.

 Firewise landscaping addresses fuels issues both adjacent to the structure and further away. These are tasks which need to be reviewed annually;

• clean leaves and needles out of gutters and out from under open decks and spaces.
• keep trees and shrubs pruned to reduce ladder fuels
• remove dead plant material including leaves, needles, grass and other combustible vegetation from the home ignition zone
• landscape with fire resistant plants near the structure
• keep grass immediately around structure mowed and watered
• Maintain  a good access for emergency responders.  Assure streets are clearly named and homes are clearly numbered.

Check the links side bar on the ‘Welcome Page’ for more information. Use the Homeowner Assessment Checklist and the FireWise Web site to keep your home safe!