Flathead County GIS has unconventional start

Flathead County, Mont., planners have adopted a unique approach in building the county’s GIS land base map. The Geographic Coordinate Data Base Measurement Management (GMM) programs developed by the Bureau of Land Management (BLM) and the University of Maine, and land data maintained by the Montana Department of Revenue (MDR), combined to form a GIS for the county that had unconventional beginnings.

Flathead County’s appeal as a tourist attraction had brought an influx of new residents that strained the county’s limited local resources. County planners needed to be able to process a large amount of information and pass resolutions to meet the needs of the population.

Officials in Flathead County began considering GIS after conducting an emergency evacuation notification exercise at Glacier International Airport. The effort, which required cross-referencing each parcel and owner within the area for notification, took nearly 20 days to complete, while a GIS could have completed the process within hours.

County planners initially expected to use GIS information from the Flathead National Forest and the National Park Service, but their land map base had only a few ground surface points, and the project required a parcelspecific base map. Accessible ground surface points are essential to GIS implementation, and very few National Geodetic Survey control stations were spaced throughout the county’s mostly remote areas.

Flathead County planners had two options: to establish an initial grid with corresponding geodetic coordinates for nearly all points, which would require extensive surveying and financial expense, or to cross-reference all certificates of survey in one central location. Both solutions involved expenses that the county could not afford.

County officials contacted the BLM for assistance because the BLM had faced a similar problem while creating the Geographic Coordinate Data Base and had already adjusted 35 townships, placing a latitude and longitude on all corners of the Public Land Survey System (PLSS) down to the sixteenth corners. GMM was an inexpensive, faster alternative that saved the county an estimated $300,000.

Building the parcel specific base map was next after establishing countywide geographic positions. After scanning and digitizing Flathead County’s 1,776 plat maps, any subsequent information to be added could be done on the system, allowing for ongoing maintenance.

The county now needed a unique parcel identification system. The MDR had developed an approximately 90 percent parcel-specific geocode, which could check for accuracy while expanding specific parcel information by combining resources. Along with GeoSQL in Denver, Col., planners combined the parcel data to the graphics.

Officials selected a CAD-based approach because employee training was available through courses offered at the local community college. Flathead County is in the process of electronically linking all departments with select municipal agencies. This gives potential users the capability to access the large amounts of graphics associated with many GIS applications, and allows for upgrading when new technology becomes available.

GIS information will soon be available to users via computer modem. which will alleviate county employee workloads and cut costs.