(NRIS is the Montana State Library's Natural Resource Information System) Description is current as of March 28, 2002 Nature & Purpose of the database: NRIS has a wide variety of natural resource information that is mapped and stored as GIS themes (compatible with ArcInfo and ArcView). The data are listed in a browsable, searchable list and can be downloaded as ArcInfo export (e00) files or ESRI shape files for Arcview. Most of the maps/GIS themes available online are for illustrative purposes or for basin-wide planning at a large scale. In most cases however, the resolution is too coarse and/or the accuracy too uncertain to use for detailed planning purposes. Some of the data sets cover the entire state and some are specific to regions. There are quite a few GIS themes available for the Upper Clark Fork due to the Superfund site work; however, the metadata for these maps is very sketchy. For many the source or accuracy of the map that was digitized is unknown. A summary of some of the available info is listed below and some of the more useful maps highlighted. Location of sample sites/areas assessed: Some of the GIS data layers are statewide, some are region specific (including many for the Upper Clark Fork Basin Superfund sites).
Time frame: Varies with type of information. Mainly from the 1980's and 1990's. Mostly one- time assessments (except for population census). Parameters available to download (brief summaries of each type of data; listed in order found on NRIS GIS web page): Statewide data:
Upper Clark Fork Regional data:
Quality of data: Much of the statewide data are meant to be used at a scale of 1:100,000 or coarser. The Clark Fork regional data vary from 1:100,000 to 1:2400. Metadata varies in quality. Sometimes no scale is given; accuracy is sometimes unknown, or stated qualitatively (fair or poor). Sometimes the source map or source data is inadequately described. Much of the most potentially relevant information is inadequately documented. See metadata for each map for more detail. Relevant reference: see metadata of each map Responsible party contact info: Gerry Daumiller, of NRIS (406) 444-5358 How to access NRIS's online GIS data: http://nris.state.mt.us/gis/gis.html click on 'Browse the GIS data list' to get to http://nris.state.mt.us/gis/datalist.html. Most of these data sets can be downloaded online, but some must be requested. Usefulness to restoration planning: Most of the GIS data available online is of limited usefulness to restoration planning due to its scale or its poor or unknown accuracy. The scale of the statewide data is too coarse. The Clark Fork regional data is of a finer scale (1:24000 down to 1:2400), more useful for restoration planning, but the metadata is often insufficient to determine the accuracy of much of these data. Many of the GIS layers were obtained by digitizing maps developed by consulting firms. Those maps included hand sketches & maps of unknown accuracy. The most useful data appear to be the base maps, photogrammetric data, and the maps from the Clark Fork River and Silver Bow Creek operable units. Of greatest use to restoration planning would be the maps of: 100 year floodplain, fine scale contours, wetland delineations (if of better quality), exposed surface tailings, bank tailings, lateral bank cutting, tailings thickness and saturated tailings It is important to remember that superfund work will alter many of these sites, removing areas of contamination and changing contours. Recommendations for making the info more useful: On the browsable list, state the map scale (1:24000) & a code for accuracy (U=unknown, G = good, F = fair, Q = quantititative data available, see metadata). This will show that most of these maps are not useful for detailed planning & save the user having to browse through the metadata. Provide more data at the 1:24000 scale or finer. Improve the quality of the metadata on the Clark Fork regional data. Where there are several versions of the same information (as with the maps of surface tailings & the 100 year floodplain), it would be a service to users to determine which information is the most reliable and eliminate the other versions from the list. For example, there are 4 sets of streamside tailings data. The CH2M Hill set was digitized by EMSL from a CH2M Hill report |