Title:
Wildland Urban Interface of Idaho
Abstract:
For the purposes of this analysis, Wildland Urban Interface is mapped using 2000 Census data and the communities listed in Idaho as "at risk" in the 2001 Federal Register (Vol. 66, Number 160, August 17, 2001), buffered by 1 mile. There were weaknesses with both data sets; data representing "urban wildland communities" are commonly not incorporated communities, nor are they areas that can be precisely located from a geographic standpoint. The Census data accounts for permanent residences only; it does not account for seasonal residences (e.g., summer cabins and ski area condominiums), or residences occurring on public lands (e.g. leased cabin sites).
Supplemental information:
Because of weaknesses with these data, a conservative approach in delineating the wildland-urban interface was used. The point layer (representing urban wildland communities) and the raster layer (representing inhabited areas) were buffered by 1-mile and then merged to develop a single layer representing the "wildland-urban interface".
The Wildlife Spatial Analysis Lab (University of Montana) reprocessed the 2000 Census data for this assessment, using a sequence of GIS filters to reassign people counted by the 2000 Census to map units that were smaller than the available block-level data. The first step involved redefining inhabited areas by excluding public lands, Plum Creek Timberlands, water features, railroad and highway corridors, steep slopes, and other local lands designated by the Census as being non-populated (e.g., commercial zones). The population counts within the inhabited areas were then redistributed using relative weights of percent slope and distance-from-roads. The weighting functions for slope and roads were determined using approximately 90,000 points representing homes that were obtained from county E911 databases (Kootenai and Idaho Counties, Idaho; Gallatin County, Montana) and electric meter locations provided by Flathead Electric Cooperative. For example, analysis of these data sets suggested that 99 percent of all people live within 1-mi of a road and on slopes less than 43 percent. Furthermore, 59 percent of all people live within 90-m of a road and on slopes less than 6 percent. A population density derived from this process was simplified into 2 classes representing inhabited and uninhabited areas.
These data were designed to characterize mid-scale patterns across Idaho of the Wildland Urban Interface, and Inhabited Areas. They were developed specifically for use in characterizing relative fire behavior which was then used to assess the risks of wildland fire to communities.
This dataset was used in the "Idaho Interagency Assessment of Wildland Fire Risk to Communities, 2007", Map 6 ("Wildland Urban Interface"), and Map 6A ("Inhabited Areas") . It was created for the Statewide Interagency National Fire Plan Working Group to which the Bureau of Land Management (BLM), Idaho is a member. It has also been used in other BLM planning efforts such as Resource Management Plans, Fire Management Plans, and NEPA analysis.
General Limitations
These data were designed to characterize mid-scale patterns across the state of Idaho at a scale of approximately 1:100,000. The use of these data at scales less than 1:100,000 is not recommended without field verification.
Although the resolution of this theme is a 90-m cell, the expected accuracy does not warrant its use for geographic extents smaller than approximately 10,000 acres. That is, these data were not designed to be used for "project level" assessments that typically require 1:24,000 scale data.
Are there legal restrictions on access or use of the data?Access constraints: Public
Use constraints:
No warranty is made by the Bureau of Land Management as to the accuracy, reliability, or completeness of these data for individual use or aggregate use with other data.
These data were designed to characterize mid-scale patterns across the state of Idaho at a scale of approximately 1:100,000. The use of these data at scales less than 1:100,000 is not recommended without field verification.
This data set is provided "as-is" without warranty of any kind, including, but not limited to, the implied warranties of merchantability and fitness or a particular purpose. The user assumes all responsibility for the accuracy and suitability of this dataset for a specific application. In no event will the creators or USDA Forest Service be liable for any damages, including lost profits, lost savings, or other incidental or consequential damages arising from the use of or inability to use this data set. Use of these data may require the ability to read ArcInfo Grid datasets.
Although the resolution of the Burn Probability theme is a 90-m cell, the expected accuracy does not warrant its use for geographic extents smaller than approximately 10,000 acres. That is, these data were not designed to be used for "project level" assessments that typically require 1:24,000 scale data.