Data layers expose trends

Technology explains some problems, prevents others

RALEIGH -- Sure, go ahead and mock the fact that Wednesday was officially GIS Day, but before you do, consider the following:

GIS, or Geographic Information Systems, is being used in North Carolina to prevent syphilis, fight crime and predict landslides.

Those were just a few of the GIS applications on display in downtown Raleigh on Wednesday, as state and local government employees gathered to demonstrate the technology's power.

GIS is software and hardware that enables information to be linked to a specific location, such as a person to an address. Layering more information onto a map enables the creation of a geographic database, which can be analyzed for patterns or trends.

Shannon Schelin, director of UNC-Chapel Hill's Center for Public Technology, said initially it was the real estate community that pushed governments to adopt GIS for the purpose of accessing property tax records.

Schelin said the cost of GIS programs varies widely -- anywhere from thousands to hundreds of thousands of dollars -- and depends on the number of users accessing the data and whether they are available to the public at large.

Although governments lag far behind the private sector when it comes to investing in technology, Schelin said officials are beginning to realize that GIS can both save taxpayers money and improve the delivery of services.

To combat syphilis, officials with the Department of Health and Human Services have been plotting reported cases for years. Dianne Enright, who manages the department's GIS efforts, said such continuous mapping allows health workers to respond to outbreaks quickly and target areas for education.

Enright said GIS also can help show underlying connections, such as when it revealed that syphilis cases along North Carolina interstates declined markedly after the state legislature banned overnight parking in rest areas.

After several powerful hurricanes ripped through Western North Carolina, the Department of Environment and National Resources began using GIS to pinpoint areas that are prone to landslides. The resulting GIS map of Macon County takes into account a range of factors -- surrounding development, existing tree canopy, soil types -- to identify high-risk areas.

In the Triangle, Raleigh and Wake County are known for openly sharing the GIS data that they capture.

When a hazardous waste plant in Apex exploded last month, Wake County GIS workers helped identify residents within the evacuation zone.

Raleigh is currently spending $1 million to have a GIS contractor spend four months driving the streets within its planning jurisdiction. The contractor is taking pictures and recording GPS coordinates every 35 feet, with the goal of cataloguing the location and condition of every sign, traffic signal, fire hydrant and street marking.

The information will be used to create a database for repairing and replacing municipal property.

Raleigh police are using GIS to plot and analyze crime data in districts across the city. The department eventually plans to make the information available online, allowing residents to quickly access the crime history around a specific address.

Technology's limits

Although GIS seems to have an infinite number of applications, the technology is not a panacea. Enright said that when Wake County recently experienced a big increase in the number of rabies cases, her group used GIS to try to explain it.

"We couldn't figure out why [there was an increase]," she said, noting the spike could have been the result of more people bothering to report rabies cases.

North Carolina has created a central Web site, www.nconemap.com, where a number of governments regularly store GIS data. Such a large public database of GIS information should make it easier for residents to develop their own GIS applications.

Michael Evans, 51, who operates a hot dog stand on Fayetteville Street, admitted Wednesday that he uses GIS sparingly. But as he strolled among the colorful maps on display at the GIS Day event, Evans began to imagine how the technology might help him.

"Yeah, they should map them out ... all the hot dog stands," he said. "Then I'd know where the competition's going."