GIS...or GI Ain't your baby?

Dave Reinke
Infolink Project Manager
APWA Washington office

Since this issue of the APWA Reporter addresses technology and software in public works, it seems a good time to address some of the latest advances in Geospatial technology, as utilized by Geographic Information Systems (GIS). GIS technology continues to evolve, and advances in availability of data and interoperability make it more compelling than ever. The Internet makes it easier to access base data and finished applications, and with the continued growth of GPS (Global Positioning Systems) and the introduction of systems such as in-vehicle navigation displays and cell phone Location-Based Services, GIS will play an increasingly important part in our everyday lives.

There are a number of software firms specializing in GIS, but the market is largely powered by a few big players. ESRI is the biggest player in specialty GIS software, with their ArcGIS suite (ArcIMS 4 is their latest web-based application). MapGuide by Autodesk is also targeted to Internet GIS delivery, as is the GeoMedia package offered by Intergraph. All of these vendors have a host of partners and developers delivering targeted solutions for vertical markets, including public works. In addition to these commercial vendors, information and support for users can be found in associations. APWA offers information, resources, and technical committees to help users choose and implement technology, and other associations such as the Urban and Regional Information Systems Association (URISA) and the Geospatial Information and Technology Association (GITA) specialize in geospatial issues and educational opportunities. URISA is even examining the possibility of offering GIS certification for specialists in this growing field.

The basics of any GIS software are the same: GIS takes data and gives it a geographic perspective, which allows users to examine that data in new ways, discern new relationships, and manage it in new ways. All the systems have three basic requirements: first, the need to have access to base data; secondly, the system needs to process and display that data; and thirdly, the user needs to manipulate and analyze the data.

For the first step, the Internet is greatly expanding the availability of data for use in a GIS system. Raw data such as population and census figures is readily accessible from government servers, and connections with real-time data sources from Intelligent Traffic Systems (ITS) allow cities such as Seattle to post maps showing up-to-the-minute information on delays and closures (this is also available for handheld devices).

Another data source increasingly available is Orthophotography (commonly referred to as aerial photography), which serves as one data layer in GIS applications. This data can be supplied at different resolutions, provided by either aircraft or satellites. The City of Edmonton, Alberta supplies photogrammetric coverage to users at different costs based on required resolution. In addition to widely available visible images, different datasets can also be imaged, from Infrared to technologies such as LIDAR (Light Detection and Ranging), used in special circumstances such as "seeing" through cloud cover or smoke. LIDAR imaging greatly assisted the GIS recovery efforts at Ground Zero in New York in the immediate aftermath of September 11, as users were able to map the damage through the smoke.

In fact, GIS is at the heart of many infrastructure protection and emergency response systems. One of the earliest uses of GIS was modeling nuclear and chemical hazards, and many municipalities are recognizing the value of knowing, and having access to, the precise locations of buried utilities, water systems, and control points. They are also increasingly aware of the need to secure access to this information, and limit use to authorized personnel. ESRI is offering a series of seminars at different locations across the country this summer entitled "SafeCities—GIS for Homeland Security," and has also announced a grant program for municipalities interested in GIS as it applies to infrastructure protection.

As more and more agencies at the federal, state, and local level are using GIS, the ability to use and share data between organizations also becomes increasingly important. Standards set by federal organizations help foster interoperability by defining technical requirements, and groups like the Federal Geographic Data Committee (FGDC) are working on standards through National Spatial Data Infrastructure (NSDI). Other organizations are also involved, such as the Open GIS Consortium (OGC), which brings together over 200 industry, academic, and government participants to standardize data as it is used by GIS systems, and the Geospatial Leadership Committee (GLC), which is working to involve the end-user communities.

While the Internet is enabling increased access to data and GIS applications, and the interoperability of those systems, the transition to wireless delivery promises even more uses. Ubiquitous wireless access can deliver GIS data to handheld PDAs like Palm, cell phones, and in-vehicle displays, and increase even more our interactions with GIS in all its forms. Think about how GIS might impact your current job, or will in the future, and learn more about it. GIS links for all of the above-mentioned sites, as well as additional resources, can be found on www.apwa-infolink.com under the Agency listing "GIS."

To reach Dave Reinke, call (202) 408-9541 or send e-mail to dreinke@apwa.net.