ects. But the seven themes, as now defined, may not fulfill the needs for more local studies by states, tribal nations, cities, and counties, for two reasons:

  1. The information the seven themes encompass is required in greater detail at the local level. For example, roads may have to be described by their edges instead of by their centerline. Property owners and local officials often need to define and locate the right of way between an individual’s property and a road. Tax maps are often the most critical resource in resolving local land use and zoning conflicts. These maps must also be integrated with the location of specific buildings and the location of utility infrastructure networks. It simply is not feasible to accurately depict these features at the map scale used by federal mapping organizations. In fact, the largest scale federal map series is still the USGS 1:24,000 series of 7.5-minute topographic quadrangles. In the local mapping community, maps of this scale would be considered small scale with a map accuracy of approximately 40 feet, based on the statistical methods advocated in the FGDC standard for specification of spatial accuracy. The base maps for large-scale mapping are often legally required to be of a scale of 1 inch to 100 feet or 1:1200.

    The requirement for large-scale source materials is critical for the development of federal-local partnerships. It must be noted that this is not the first time that a NRC committee has highlighted the need for federal support for the development of a nation-wide database that accurately depicts individual property ownership records (see Box 5). The committee is pleased to note that the FGDC has recognized this need for increased resolution, concluding in its 2000 assessment of the Community Demonstration Projects that “…many federal datasets lack sufficient resolution to support local planning needs…” and advocating that “…federal agencies should continue to enhance the quality of data using the latest technology…” (FGDC, 2001).

  2. Additional themes may be needed at the state, tribal nation, county, and city levels: for example, water rights in the western United States, or utility information at municipal levels. It is clear that not



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