Saturday, July 12, 2008

Insurance Requirements Threaten Slope Stability

Western North Carolina mountain homes and private developments are being evaluated for wildfire threats. As a result property owners are being confronted with the risky choice of whether to minimize an insurable risk or maximize an uninsurable risk.

The 2007 Hazard Assessment and Mitigation Plan for Leatherwood Development provides a look at the issues. This subdivision is located in western Wilkes County. The following was extracted from the Leatherwood Report:
The Leatherwood Development is located in an area with a potential of wildland fires that can threaten the structures within the development. As requested by the Leatherwood Development, the North Carolina Forest Service has surveyed the development for the purpose of assessing the fire hazards and to recommend practices that can lower the overall fire hazard rating.

Development Description:
The development currently includes approximately 120 homes including rental cabins and both part time and full time residences, however many more are planned to be constructed within the next few years. The development is located within an area of timberland that covers approximately 3800 acres. The topography is very steep and rugged with all slope aspect represented.

The structures were evaluated independently throughout the area and the development evaluated as a whole using the NC Division of Forest Resources hazard assessment rating system.
The Leatherwood Development received a high risk score of 111 points just under the >112 extreme risk rating. The Report concluded that:
By applying Firewise principles to the entire development, including additional structures that will be built in the future, the hazard rating can be decreased. The goal should be to decrease the rating to a moderate level, which will be difficult in this particular development.
Poor planning has placed Leatherwood property owners at substantial risk. Homeowners can reduce the probability of fire damage by removing highly flammable vegetation such as cedar, pine, hemlock, and rhododendrons from around their properties but they cannot move their homes, reconfigure roads, or easily provide accessible water. The Leatherwood Report found that:
Slopes range from 10% to 70% with side slopes and ridges that will greatly affect the overall fire behavior of a wildfire in the area. The homes currently located in the development are steep side slopes that are vulnerable to fast approaching upslope fire from below. As new homes are constructed in the rough topography, this will increase because of the limited level homes sites.
It is important to note the following recommendations concerning Fuel Clearance Zones and Vegetation:
Thin out the understory and midstory trees and shrubs within critical areas within the 300 feet zone around the home. Critical areas include areas with thick understory especially on the slopes underneath the structure. Create park like environments in these areas where fuel loading is lowered. The understory shrubs and trees can be felled and the stumps treated with herbicide to prevent resprouting.
Unintended Consequences

Insurers have determined that reimbursing property owners for landslide property damage is an unacceptable expense and as a consequence they have excluded earth movement coverage from all homeowners' policies. Insurance industry professionals have compiled data about the probability of slope failures and according to Robert Hartwig, President of the New York-based Insurance Information Institute, “Homes in these areas ( mountain slopes) are accidents waiting to happen."

The insurance industry is keenly aware of wildfire probability and the expense of insuring against this natural hazard. Homeowners are discovering that the availability and costs of fire insurance are predicated on complying with wildfire mitigation standards.

The Leatherwood Community is located in a fragile environment where erodible soils and landslides are easily activated. If native vegetation is removed to the extent proposed by the Forest Service, this already unstable ground will be further degraded.

Which of the risks should mountain slope property owners address: landslides or wildfires?

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