Montana's GIS-Based Cadastre Layered with Riches

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As the fourth largest state in the United States, Montana is synonymous with frontier. Under the state’s famous "big sky" are 145,552 square miles of sparsely populated open land, and– ranked forty-fourth in total population and forty-eighth in population density–Montanans, in general, like it that way. While the state’s demographic database may not be diverse, its geography most certainly is.
Running in a diagonal line from northwest to south-central Montana, the Continental Divide splits and roughly defines the topography of the Big Sky state. West of the divide stand the northern and central Rocky Mountains, while east of the divide are mostly prairies and plains. Meanwhile, rivers; lakes; forests; national parks and monuments; long, lonesome highways; Canada; and four other U.S. states divide, dot, and border Montana’s 56 counties.

Managing all the geographic data associated with a territory as immense as Montana is no small task. The state recognized this challenge and pioneered a geographic information system (GIS)-based statewide cadastral database. Montana’s spatial data infrastructure (SDI), as recognized by the Montana Land Information Council, consists of 14 layers, with the cadastral layer being one of the most mature. The layer is based on the tax cadastre, a legal repository of land records that indentifies the owner, location, boundaries, description, and property rights associated with a parcel of land. Montana’s cadastral layer is most closely associated with the property assessment processes, but usage of the data goes far beyond the state Department of Revenue (DOR).

"More than half of government business processes are associated with parcels," says Montana Base Map Service Center (BMSC) chief Stewart Kirkpatrick. "Questions like, `Who owns that parcel?’ or `What features are associated with this parcel?’ are a constant at the local and state levels. It made sense that we, the State of Montana, had a standardized digital cadastre system that everyone could access."

According to the U.S. Office of Management and Budget’s Federal Enterprise Architecture framework, Kirkpatrick is right. The framework states that 74 percent of government data is location based, and that number is even higher at the state and local levels. Back in 1996, Montana hired Kirkpatrick as the project manager to explore the concept of a statewide cadastre, build a project plan, and obtain funding to collect and maintain tax parcel data in a standardized format. Recognizing how their organizations could benefit from a statewide cadastre, the United States Department of Interior (USDI) Bureau of Land Management (BLM), Montana Power, Burlington Northern, and Montana Dakota Utilities all signed on as major contributors to the project.

With initial funding in place, the conversion of paper records to digital format commenced in 1998, and in 2003, when the new digital tax parcel framework was complete, Montana had the only statewide cadastral database in the nation. Although the data was available by then, full benefits, such as a return on the state’s $3 million cadastre database investment, were not realized until 2005. That initial investment included the development of the cadastral database. It also included the five-year task of paying contractors and state staff to convert, standardize, and integrate mostly paper-based data from approximately 900,000 parcels into the new GIS-based cadastral database. The transformation began paying off faster than the state had even imagined.

By 2009, the state estimated the minimal annual value of its digital parcel and cadastral data at just over $10 million. It figures that the annual return on investment (ROI) is $9,335,700. ROI figures came from a Montana state study that focused on the value and costs associated with the cadastral system including an evaluation of the IT investment in the cadastral layer; identification of business processes, users, and beneficiaries that depend on the cadastral layer; identification of the relationship between the cadastral framework and the other 12 framework layers; and development of a financial analysis that documents the current and ongoing costs and benefits of the cadastral layer.

Just as a cadastre is a cornucopia of information related to land, an abundance of government agencies lend data to the system. DOR and eight counties collect the tax parcel data, while other agencies and interests collect ancillary data on conservation easements; municipal and school district boundaries; special districts like water, sewer, and mosquito; and other data that conveys rights and interest on the land. It is the BMSC’s responsibility to integrate the tax parcels and related data into a statewide database monthly and link the tax parcels to DOR’s computer-assisted mass appraisal (CAMA) system, ORION. BMSC also integrates the BLM’s geographic coordinate database (GCDB) as the digital representation of the public land survey (PLS) in Montana, since the PLS is the foundation of landownership in Montana.

All cadastral data, including parcels, and other spatially coincident feature classes are stored in an Esri geodatabase by BMSC, while DOR’s tabular data is moved to an Oracle database linked to the parcels. The data is housed in an enterprise GIS, then distributed as shapefiles and geodatabases where businesses, organizations, and other interested parties can go for cadastral data and maps.

Citizens, private organizations, and various state and county agencies use the cadastral information in a wide variety of ways. The state’s multiple cadastre-based, public-facing Web sites have been used for anything from pipeline construction to finding a place to hunt. BMSC distributes the information to the public through the Montana Cadastral Mapping Application ( Montana State Library’s GIS portal Web page ( is the distribution point for metadata describing the state’s cadastral database.

POWER Engineers Inc., a global engineering firm based in Hailey, Idaho, is an example of a private organization that appreciates the ease and speed of acquiring data from Montana’s cadastral Web sites. Over the years, the firm has downloaded copious amounts of data for various Montana infrastructure projects, such as routing transmission and telecommunications lines, and subsequent management of rights-of-way acquisitions.

POWER Engineers’ recent business in Montana includes replacing old 115-kilovolt (kV) transmission lines with the larger 230 kV lines. The new transmission system may utilize the same corridor, but in some cases the upgrade requires that more rights-of-way are acquired to accommodate the bigger structures. When routing a proposed power transmission corridor, the cadastral data can be used to minimize easement acquisition costs.

"We get data straight from the Montana cadastre Web sites and plug it into our own GIS," says POWER Engineers consultant Scott Chapman. "It’s as easy as going to the Web site and selecting the county we’re working in, then downloading the data."

When dealing with other states and counties, POWER Engineers occasionally has to get project data from old plat maps, then go through the tedious process of digitizing. Chapman points out that Montana’s cadastre data is standardized, unlike many other states. "The state of Idaho has 44 counties with 44 different standards,"
says Chapman. "Having current and standardized data from Montana’s cadastre saves us a lot of money and time, sometimes even weeks. For POWER, that is a cost benefit for our clients. It’s a huge time-saver for any private company and the public."

While private organizations and the public can access the information-rich cadastral data via the Internet, state, county, and local municipalities can not only access the system but they can also link their own GIS solutions. The GIS-based cadastre has proved to be a significant time-saver for all kinds of small and large government tasks. In addition, BMSC also provides hundreds of hours of assistance annually to local governments maintaining their own cadastral databases and holds educational workshops and seminars to expand cadastral knowledge.

Montana’s Butte-Silver Bow is just one of the many local governments to reap the rewards of the digital cadastre. As the director of Butte-Silver Bow’s Planning Department, Jon Sesso oversees a residential metals abatement program. Having cadastral data easily accessible in a GIS is important to the city-county government, especially when a property is sold. It’s a high priority to test for and abate the presence of toxins, especially at properties where children live, because youth are extremely susceptible to dangerous chemicals, such as lead, found in or around a home.

When a property is sold, it gets recorded in the county’s GIS, which then alerts Sesso’s department. If the property has already been tested, then no action is taken. However, when a property that has not been tested changes ownership, performing a test becomes a high priority since the new owners could have children.

"Once the property is freed of whatever harmful matter it had, the property owner signs a waiver saying that the house is clean, and that gets added to the county land records, which are linked to the local and statewide cadastral system," says Sesso. "Having these land records digitized in the cadastral system has been a tremendous help for us. We have a legal obligation to keep track of where we have tested, where we’ve done abatements, and where we haven’t."

The Montana Department of Natural Resources and Conservation (DNRC) has obligations of its own, and one of the most important is to protect both the land owner’s and the state’s water rights. In addition to linking its water rights database directly to DOR’s ORION system, DNRC also uses the cadastral system for its management of school trust land. The agency manages approximately 5.2 million acres of state school trust land (state land), forests and agricultural, grazing and commercial properties that earn revenue to help fund public schools and universities. Agency Director Mary Sexton points out that most of the western states that were given school trust lands at statehood have long since sold their land, only to gain the interest generated from the sale. But not Montana. "We retained most of our school trust land, and by managing these lands, we generate more than 60 million dollars a year for our schools," says Sexton proudly.

With a standardized, Web GIS system, keeping track of and working with data related to a cadastre doesn’t get much easier, even in a place as massive as the Big Sky state.

Note: For more information, visit or contact Montana Base Map Service Center chief Stewart Kirkpatrick at

Matt Freeman is a writer for Esri.

A 1.963Mb PDF of this article as it appeared in the magazine—complete with images—is available by clicking HERE