Graphic: Aerial photo overlaid with the county highway map and home locations from a local high school project. The program has already located and assessed approximately 100,000 residential structures. As of early 2006, an estimated 400,000 point features have been collected.

On July 4, 1999, Minnesota experienced a "blowdown" -- a windstorm that flattened 600 square miles of forest in the Boundary Waters Canoe Area. After a massive rescue effort of holiday visitors, the state was left with a very large fire hazard. "We had a fuel load that was in excess of anything we had seen before," said William Glesener, Firewise specialist for the Minnesota Department of Natural Resources. "Since then, we've had several fires up there, and we recognized that we needed to manage the Wildland/Urban Interface. So the state of Minnesota got on board with the national Firewise program, and started looking at things we could do, and things we might need in case of a catastrophic event."

At the time, incident management teams were doing some mapping of homes. "Tom Eiber was the person in charge of the DNR's Firewise program at the time," said Glesener, and it soon became apparent that there was a lot at stake and a bigger view was needed. "We needed to know where the homes were," said Glesener, "where the hydrants were, where the fire stations, nursing homes and hospitals were."

In addition, said Glesener, there was a need to track hazards to low-flying aircraft. "There are three different entities that are tracking stuff above the treeline," said Glesener. "The FCC tracks things that broadcast, the FAA tracks things that are over 110 feet tall, but you have a potential for a local building that is above the treeline but is not 110 feet tall such as a lookout of fire tower that isn't registered ... In helicopter operations during wildfires, that can be a great concern, so we starting looking around to get all that data together."

The result was a comprehensive aerial obstruction dataset, and momentum that carried forward into discussions with the DNR's Management Information Systems staff -- as well as other federal and state agencies -- to find a better way to help emergency managers.

"The premise of the program," said Glesener, "is basically 250 features that Tom originally identified. We were collecting the point attributes, but as the thing built, and we got over 120,000 homes into the system, we realized we wanted to add attributes. There are 10 static attributes we collect, such as the feature type, the location, who actually got the information, and when it was collected, verified and approved. Those are static."

"We also have flex fields," said Glesener, "15 other attributes in the database. It's just a column, but it gets tied back to the actual feature type. The flex field one for a fire department is the station number. For a home, it is the E-911 address. But if you open up the database, you can see all that stuff in the same column. That's where the Java-based Web application comes into play."

The system utilizes Spatial Oracle, UMN MapServer and Java. Javascripting builds the front end html code for Web display.

"We're allowing that one big dataset to be displayed and have those flex fields displayed with other values based on the scripting behind the scenes. One of the nice things about that, is that we're able to attach files to these point locations. So conceivably, we could attach 15 files to a single point -- they can be PDFs, Word documents, spreadsheets, etc. It could be another database. So you can exponentially increase the amount of

Wayne Hanson  |  Senior Executive Editor, Center For Digital Government