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Dealing with Data Distribution Issues
By Christopher Thomas, Government Solutions Industry Manager

Sooner or later, every GIS manager gets a request to provide GIS data to a consultant or third party. On the surface this seems like a simple and straightforward request. It usually starts with an exchange like this:

"Hello, I am a consultant for the city, and my company needs some of your GIS data to complete a city project."

A variant of this request is:

"I am a local developer, and I need your map data to bring companies to the community."

Does this sound familiar? Depending on where your city or county is in the implementation life cycle, you will probably give one of the five responses listed below.

  • We've just begun building our GIS and the data is not ready for distribution. (Translation: I do not have confidence in my data yet, and I am not prepared to take criticism so I am going to stall any and all requests.)
  • We have been building our GIS infrastructure for some time and have tested the data so we have confidence in it. (Translation: We invested a lot of money in this GIS. This data is worth a lot of money. Stall all requests.)
  • Our data is available for sale. (Translation: We are convinced we can pay for or offset the costs of our GIS by selling our data. Stall all requests until we receive a check.)
  • Doesn't anyone want to buy my data? (Translation: While the requests for GIS data came in occasionally, there hasn't been a mad rush to buy it. Taking a proactive approach to selling and marketing the data could take a lot of resources and detract from the department's real work. Besides, we really didn't make a lot of money on the data we did sell.)
  • I need to figure out a mechanism to deliver data to consultants and outside requestors. (Translation: The GIS was implemented to support our organization's projects. I need to develop a way of fulfilling requests.)

As the requirement to make GIS data available becomes pressing, GIS managers face issues that the managers of other departments and persons outside of government may not fully appreciate. These issues range from balancing the Freedom of Information Act with concerns for public safety stemming from more recent homeland security measures. Often this is complicated by concerns over protecting the government entity from lawsuits related to misuse, misinterpretation, or misrepresentation of raw GIS data.

Distributing raw data can also cause more work for the GIS department. GIS staff may spend time fielding questions posed by outside interests who may not be GIS savvy or understand the data design. Unfortunately, the government entity becomes the de facto technical support mechanism for the recipients of GIS data whether there are resources for this task or not. The result is that these inquiries may detract from city work.

Once the data leaves the organization, there is no compelling argument for the requestor to obtain updates and nothing stopping the requestor from passing the data on to another party. Consequently, in this scenario, a government agency cannot prevent the use of old data on projects.

However, there are two strategies that can help GIS managers respond to requests for data by consultants or third parties. Serving maps and data via a GIS-enabled Web site powered by ArcIMS is one approach. Publishing portable map documents that can be viewed and queried using the ArcGIS Publisher extension with the free ArcReader is another method.

Using ArcIMS helps government agencies handle many of the issues associated with providing access to spatial data. A GIS Web site provides both citizens and businesses with access to this data 24 hours a day, seven days a week. New and innovative government services have been developed using GIS data and ArcIMS applications. Current data, along with metadata, can be made available. Safeguards—such as data reformatting—protect individuals' records, and applications that prevent the misuse or misinterpretation of data can be incorporated into the site.

Many government sites allow data to be downloaded through a data portal similar to the Geography Network, but not all agencies have embraced this idea. For these agencies, ArcGIS Publisher may provide a solution for data distribution. This extension to ArcGIS ArcInfo, ArcEditor, or ArcView gives governments another vehicle for sharing data and distributing maps. With ArcGIS Publisher, data and maps can be assembled and delivered on CD-ROM, over the Internet, or from a local area network. The end user can interact with the map data using the no-cost ArcReader application. ArcReader is a simple solution that eliminates many of the technical support and data issues that often occur when extending GIS to new users.

With ArcGIS Publisher, access to enterprise data can be provided but controlled. ArcGIS Publisher provides options for password protecting the content, the data can be set to expire and time out, or the data can be linked to an ArcIMS or Web services site so the data remains current. This prevents the use of outdated datasets while providing security.

Either strategy or both can be used to handle data distribution challenges faced by GIS managers. Implementing a data delivery strategy will let the GIS department respond in a way that benefits the city or county, protects it from liability, and does not burden staff. For more on using ArcIMS for data distribution, visit To learn more about using the ArcGIS Publisher extension with ArcReader, visit

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