Geographic Information Systems (GIS)

Purpose & Definition

Under the Superfund program, and with a grant from the Atlantic Richfield Company (ARCO), the Butte-Silver Bow Geographic Information System (GIS) Department was initiated in 1990-91. The GIS Department is charged with providing timely and accurate GIS information to all Butte-Silver Bow local government departments, as well as various state, federal, and private entities.

A large part of the information provided is in the form of hard copy maps, which are generated using ARCInfo GIS software then plotted on an inkjet plotter. The textbook definition of GIS is "an organized collection of computer hardware, software, geographic data, and personnel designed to efficiently capture, store, update, manipulate, analyze, and display all forms of geographically referenced information."

Plot Maps

Data or information used to plot maps are derived from a variety of sources. Various scale plan metrics (or topology) for features such as roads, streams, railroads, building roof prints, contours, transmission lines, etc., are produced from aerial photography, which has been photogrammetrically processed by various commercial vendors or by state or federal government mapping agencies.

Political and administrative boundaries such as fire districts, legislative boundaries, precinct boundaries, and commissioner districts are created by digitizing the original hard copy maps and using the recorded legal boundary descriptions for reference.

Land Records Data

At the heart of Butte-Silver Bow lies the ownership or land records data. Land records data, known also as the cadastral or ownership base, have long been generated using existing Montana Department of Revenue parcel base maps, mining claims maps, and property legal descriptions. Information about each parcel is contained in the Montana Department of Revenue's Computer Assisted Mass Appraisal System (CAMA) data, which is updated on a regular basis.

The CAMA data provides owner name, address, property type, building information, and much more. To download the data for Butte-Silver Bow, visit the GIS website, choose data from the menu on the left side of the page.You will see a directory of counties in Montana. Choose Silverbow, then download the files you need.

Data Acquisition

In combination with the CAMA data described above, the land records data is used for both mapping purposes and for producing reports listing information such as ownership, addresses, assessed valuation, building information, zoning, and so on. Acquisition of this data was driven by the necessity for Butte-Silver Bow, along with ARCO and the Environmental Protection Agency (EPA), to be able to identify properties affected by or affecting Superfund sites. BSB GIS has completed digital land records for all the urban area and a good share of the neighboring communities and rural areas in Silver Bow County as well as for the Anaconda-Opportunity-Warm Springs Superfund area in Deer Lodge County.

Partial List of Data Available from GIS

All of the following data carries with it relevant attributes or information in database format; thus the data can be extracted and/or spatially analyzed for display purposes and/or for supplying a digital or hard copy report. In addition, BSB GIS has a Global Positioning System (GPS) with which the location of any feature(s) on the ground can be collected and entered into the GIS, and ultimately mapped and/or analyzed.

  • Ownership/Land records (by section) and appraisal data, mining claims
  • U.S. Public Land Survey - township, range, and section lines
  • Zoning and Master Plan boundaries
  • Administrative and political boundaries (fire districts, legislative districts, precincts, school districts, commissioner districts, etc.)
  • Superfund (waste dumps, reclaimed areas, soil sampling sites/data monitoring wells, mine shafts, operable unit boundaries, etc.)
  • Soils data (not yet completed for Silver Bow County)
  • Floodplain (revision by FEMA pending)
  • Topologic features (roads, hydrography, buildings, railroads, contours, wooded areas, etc.)
  • Infrastructure (water mains, sanitary and storm sewer lines)
  • Parks and Recreation (parks, fields, trails, and trailheads)
  • Vegetative cover, Digital Elevation Models (DEMs)
  • U.S. Census data
  • Historic information and features
  • Miscellaneous other data (Inquiry with GIS Department)

Other Data Map Sources for Butte-Silver Bow

  • Aerial photography
  • Montana Cadastral
  • Montana GIS Clearinghouse
  • Montana Department of Natural Resources - DNRC
  • Montana Department of Transportation - MDT
  • Public Land Survey System - PLSS
  • Natural Resource Information System - NRIS
  • EPA (Superfund)
  • Topofinder, interactive map selection
  • Historic maps and data

Please visit our Maps & Related Data page above to view and download maps available on our website.