Integration Broadens Appeal of GIS Data
- By Cheryl Gerber
- Oct 31, 1999
State and local government users are on the leading edge when it comes to integrating geographic information systems. Whether they have built GIS into the back ends of other applications or into World Wide Web-based front ends, agencies are confronting disparate data types by using a mix of name-brand products and GIS vendors' tools.
In September, for example, Hurricane Floyd provided an opportunity for the South Carolina Department of Transportation to test a newly integrated GIS system based on Intergraph Corp.'s GeoMedia Web Map product. SCDOT had built the Hurricane Evacuation Decision Support System in June. By September, HEDSS was used to manage the 700,000-person evacuation of the South Carolina coast.
A series of smart maps incorporating evacuation routes, traffic counters, detours and real-time weather data, HEDSS is designed to make fast-changing traffic and weather data available to state emergency personnel from any Web browser. "We took 8,000 hits per day on the Web and thousands of calls during the peak of the flood," said Mark Hooper, manager of Web development for SCDOT. "Information was up to date within minutes of a road closure, so anyone with Web access would know."
Hooper used many Adobe Software Inc. products, Microsoft Corp.'s FrontPage and Macromedia Inc.'s Drum Beat 2000 to produce active server pages for the flood information. He used Adobe Photoshop to highlight areas indicating a partial road closure, full closure or water on the road. "The active server pages made it easy to update the information," he said.
Intergraph and SCDOT built three views of the data: an underlying map of highways, cities and counties with evacuation routes and detours; a layer of weather radar data; and a layer of hurricane tracking data.
HEDSS served up live data from multiple sources, such as the National Oceanic and Atmospheric Administration and the Federal Emergency Management Agency, by using GeoMedia WebMap data servers, which make live connections between multiple data sources without data translation.
One of the biggest challenges was to retrofit existing data into the new system. For example, SCDOT had pushed its traffic recorder data from a legacy system into a Microsoft Excel spreadsheet. Paul Deaver, the Intergraph SCDOT systems consultant, wrote driver code to enable GeoMedia to access traffic counter data directly from Excel.
Although GeoMedia Web Map eased some data integration problems, Hooper and Deaver said data integration is still the biggest challenge for GIS. "If you have software that can only read proprietary data, then data integration becomes a nightmare," said Steve Reed, Intergraph marketing manager.
Application integration is another hurdle. The Open GIS Consortium Inc. has made some progress with its release of the Simple Features Specification, which will make it easier to share data among GIS and non-GIS applications.
However, integrating GIS applications with commercial off-the-shelf products is still a problem because the specification hasn't been out long enough to have been implemented widely, said David Sonnen, president of Integrated Spatial Solutions Inc., Blaine, Wash., and a GIS consultant with International Data Corp.
The Street Division of San Diego's Transportation Department tackled GIS integration when it linked finance, public works and information technology, said Stephen Benner, director of business partner programs at Environmental Systems Research Institute, Redlands, Calif.
To accomplish the integration, the Street Division developed three proj-ect requirements: improve customer service by implementing SAP America Inc.'s sales and distribution module to track interactions with customers; implement SAP's human resources module to automate employee statistics and end the paper system; and take control of GIS assets.
San Diego already had a database in ESRI's ArcInfo and ArcView GIS products, with hooks to an IBM Corp. mainframe system, said Joe Chaffee, public sector manager of Conley, Canitano & Associates (CCAI) Inc., an SAP and Oracle Corp. integrator in Cleveland.
Chaffee was tasked with integrating ESRI and SAP products. He began by creating a spatial interface on SAP using Visual Basic.
But it took 135 custom programs to make the spatial data layer in the SAP relational database functional. All were written in AML, the ESRI-advanced macro language. "We had to clean up the data-eliminate irrelevant data-to make it operational," Chaffee said.
Using ArcInfo and ArcView, CCAI performed geocoding; that is, they took the location of data and plotted it on a map.
At the end of the data integration process, 1 million objects were represented in 15 asset layers, ESRI's Benner noted. The million objects represent Street Division assets such as pavement, stop signs, street lights and even trees.
While GIS is no longer a novelty in many agencies, the integration of that information with enterprise systems, such as enterprise resource planning software, and the broadening of access to GIS data is new, said Henry Morris, IDC vice president of data warehousing and applications.
"A wider audience leverages the benefits of GIS if this information is in places where you didn't have enterprise application suites like SAP or Oracle implemented," he said.
New York state is about to deploy a Web-based front end to broaden GIS access to a wider audience of users who do not have the back end benefits of an ERP system such as SAP.
"We have been using GIS for traditional analytical purposes for years. What's different for us is an Internet application about to go public in a couple of weeks," said Glen King, assistant commissioner for the New York State Division of Housing and Community Renewal, which provides housing for low-income families and the elderly.
This month, the state will launch the Web-based Affordable Housing Directory (AHD) to enable citizens to locate affordable housing by using a Web browser at a local housing office or library. "Users can click on a building, and it'll provide detailed information about the building, the telephone number, the manager, plus other community information, like where day care centers and hospitals are located," said Bob Kelly, chief of data processing services.
The AHD is based on MapInfo Corp.'s MapXtreme, a Web-based map server, and is linked to a back-end Oracle database on a Windows NT server. A GIS developer used Microsoft active server pages and Hypertext Markup Language to create the frames viewed by the Web browser and linked to data from MapXtreme. Users can place a cursor over the object, and it retrieves information for that object, said Keith McKeever, project coordinator for Geographic Data Link LLC, Troy, N.Y.
The ease with which this and other GIS applications are taking on Web front ends shows how quickly GIS is gaining acceptance and becoming so common that it is barely noticed.
"Spatial technology will become increasingly invisible as it grows more integrated into applications and as the Internet makes it really easy to access. All you need is your browser," Sonnen said.
-- Cheryl Gerber is a free-lance writer based in Kingston, N.Y.