When a fire, burglary or accident occurs in Rappahannock County, Va., the citizens call the county sheriff's office. That's the way emergencies have always been handled in the quaint rural county nestled among the Blue Ridge foothills. Up until about 10 years ago, callers only had to give their names or describe where they lived, and the sheriff's dispatcher usually knew where to send the emergency units.
      That small-town atmosphere changed, however, in the 1980s when the pristine countryside began luring in retirees looking for a peaceful place to settle, and the inexpensive real estate drew baby-boomers who didn't mind the 90 minute commute to Washington, D.C. In less than a decade, the population of Rappahannock County grew substantially, and the quiet county was suddenly too big for the sheriff's office to know everyone on a first-name basis.
      "The growth made it more difficult to provide adequate emergency services," said John McCarthy, Rappahannock county administrator. "The dispatcher couldn't possibly know where everybody lived, and the new people often were not familiar enough with the area to give directions over the phone."
      In 1989, the County Board of Supervisors began looking at 911 systems that could provide the emergency response services suited to the needs of the growing county. The 911 service is an emergency telephone response system available to 70 percent of the U.S. population but accessible in only 25 percent of the nation's geographic area. Like many rural counties, Rappahannock was in the region without 911 and also had no street name and house numbering system, which made emergency response an even greater challenge.

The 911 Options
Most jurisdictions equipped with a 911 service have Enhanced 911 (E911), which is a product provided by the local telephone company. E911 uses Caller ID technology to determine the location of the incoming call and display the caller's address on a dispatch screen. Many cities and counties have upgraded their E911 with computer-aided dispatch systems offered by third-party vendors. These systems tie into E911 and display additional information that assists the dispatcher in locating the emergency and sending the correct response units to the scene.
      "Right from the start we realized we needed two things from a 911 dispatch system - graphic maps and database capabilities," said Rappahannock County Sheriff John Woodward.
       The sheriff explained that maps were a necessity because the dispatcher needed to see where the emergency was located to properly direct the response crews through the maze of hills and hollows in the mountainous county. Years of experience also told Woodward that dispatchers need database access to correctly locate emergencies in the many instances when the distress call originates from another location.
       A county advisory committee conferred with surrounding counties, examined the 911 products available, and by mid-1992 decided to purchase E911 from the local phone company a computer-aided dispatch and map display system called View 911™ from Autometric Inc. of Alexandria, Va.
      Rappahannock chose this particular commercial product because of its interactive map display and database capabilities, according to John McCarthy. While the other computer-aided dispatch products display vector maps that show no building structures or physical features, View 911 was more appealing due to its use of digital U.S. Geological Survey topographic quadrangle maps.
      "Vector maps are too difficult to read and don't contain enough information," said McCarthy. "But everybody in a rural area has seen and knows how to read USGS topos."
      In creating the dispatch product, Autometric tapped into its 35 years of experience developing remote sensing, digital mapping and spatial database systems for the U.S. government. Autometric employed a digitizing software called Arc Digital Raster Graphics (ADRG), developed by the Defense Mapping Agency, to scan the topographic quad maps for inclusion as the basemap in View 911.
      "The ADRG process makes our product possible. Compiling the digital USGS database with any other system would simply have been too expensive," said Chris Salmon, Autometric's project supervisor for the Rappahannock system. "ADRG scans the maps, rectifies them and creates a seamless map database in any scale or map format the customer needs."
     Autometric developed the 911 dispatch system with a spatial data processing toolkit software called GeoServer™. This commercial software gives the 911 system database functionality similar to that found in many geographic information systems. Once the system is fully operational in the Rappahannock Sheriff's Dispatching Center in Washington, Va., several other county offices plan to access the database for a variety of demographic and administrative functions.

Preparing for 911
Even the basic 911 service is useless without street names and house numbers to help direct emergency crews to the right location. As part of its contract to provide the dispatch system, Autometric was responsible for developing an address system for the county.
      "Naming the roads was a real public relations challenge," said Autometric's Salmon. "In rural communities, people generally don't like having street signs posted for aesthetic reasons. And sometimes just getting them to agree on one name for a road can be difficult."
      The Rappahannock Fire & Rescue Association took the lead in establishing road names. In most situations, a road already had a commonly accepted name. But in some cases, roads that stretched across the county had several names in different areas. Those decisions were eventually left up to the citizens, and only one roadway still changes its names in the middle.
      In Rappahannock, 82 percent of all emergency calls come from residences on private roads. These were all named as "Lanes" so that responding emergency crews would know to expect a trip down a dirt or gravel road.
      To conduct the building numbering, teams of off-duty firemen, paramedics and sheriff deputies were hired to scout the area on foot, assigning numbers and verifying the accuracy of the topo quads. House numbers were assigned sequentially along each road starting from the south or west.
      A total of 200 numbers per mile were assigned so the house address would correlate directly to its location from the beginning of the road. That would help emergency crews find the structure even if its number weren't posted outside.
      The survey crews walked every road and driveway in the county assigning numbers. They used GPS equipment to verify the location of all building structures on the topo maps and add new structures to the map database.
      "House locations already marked on the topo maps were seldom off by more than 30 feet," said Salmon.
      The crews entered a physical description of the house's exterior and made notes about gates, bridges and other property features that may impede emergency units. The inhabitants of each home were interviewed to determine how many occupants normally lived there or if anyone had medical conditions that may require special care.
      All of this information was loaded into the dispatch and map database. Naming, numbering and accumulation of this correlative data took about two years to complete.
      "One of the interesting side-benefits of this approach was that our emergency personnel became reacquainted with every road and structure in their service area," said McCarthy.

Operating the System
Autometric installed the View 911 system in the sheriff's dispatching center in April 1994. It runs on a standard Unix-based 486 personal computer with a 21-inch color monitor. By May 1, 1995, Sprint Centel, the local phone company, will install a Liberty 911 console, which is equipped with an external port to transmit data directly to the computer-aided dispatch system.
      In a typical emergency situation, a caller anywhere in Rappahannock County dials 911 and the call is routed directly to the sheriff's dispatch center. The E911 system traces the origin of the call and identifies the address. This data is instantaneously ported to the View 911 system where the database is queried to retrieve all information about that address and display it on the dispatcher's screen.
      The dispatcher sees a 1:12,000 scale color map with a flashing arrow pointing to the caller's location, which is always displayed at screen center. Unless the dispatcher chooses a different scale, the displayed map covers about three square miles around the emergency location. All standard USGS map symbols are shown in color to indicate the presence of roads, driveways, buildings, woods, water bodies and other significant features. Locations of police and fire stations have been highlighted for quick identification.
      Several text boxes appear with the map to provide database information. The most important is the Emergency Response Code, which tells the dispatcher what rescue units are responsible for any given emergency address. In a typical fire situation, the dispatcher sends a primary unit and a backup, both identified by the system. If additional units are needed for large emergencies, the dispatcher can examine the map to determine which other companies should respond, based on their proximity.
      "There are six [emergency response] due areas in the county," said Sheriff Woodward. "In the past, the dispatcher had to guess which company was responsible for emergencies on the border of two due areas. This system eliminates that problem."
      Another text box provides the address and physical description of the emergency location. It notifies the dispatcher of any features, such as a narrow drive or weight-restricted bridge that may impede a rescue. In that case, the dispatcher may direct the Flint Hill or Washington fire companies to send their brush trucks instead of a large pumper unit.
      The database also provides other crucial information that was gathered by the personal interviews. For instance, if the text display reveals a resident at the emergency scene has a history of heart trouble, the dispatcher knows to scramble the cardiac unit from either the Washington or Amissville rescue companies.
      "This minimizes the information that must be supplied by the caller," said Woodward, noting that the panicky caller often depicted on TV shows also exists in real life and sometimes gives incorrect information.
      To relay the emergency information, the dispatcher radios the necessary units and gives them verbal instructions. Each fire, sheriff and paramedic unit in the county carries a hardcopy map set of the topographic quads. If they are unfamiliar with the address, they can identify the emergency location on the map using a simple grid identifier supplied by the dispatcher.
      If the crew still has trouble finding the address or if the site is located far off the roadway, the dispatcher can use the mouse to click on the screen and measure the distance from a major intersection to the desired location. The dispatcher can then verbally guide the emergency personnel to the scene.
      In the event of a serious accident in remote parts of the county, medivac helicopters are called in. The color-coded topo map allows the dispatcher to guide the pilot to a safe landing in a clearing near the mishap. The dispatcher can also provide latitude-longitude for the helicopter's inertial navigation system.

Using the Database
Sheriff Woodward pointed out that many 911 calls originate from a location other than where the emergency is actually occurring, and that is when he feels the database capabilities really come in handy. View 911 allows the dispatcher to perform database searches with several different query parameters.
      For instance, if a neighbor reports the house next door is burning, the system shows the location of the caller, not the burning house. The dispatcher can point and click with a mouse on the house next to the caller's and get its address and all relevant information. All the caller has to do is provide the dispatcher with a last name, phone number, address or good geographic description of the emergency scene, and the dispatcher can query the system either by point and click or direct data input.
      Although Rappahannock's system will not be completely functional until June 1995, the database has already provided assistance in several situations where E911 would have been insufficient. In the following situations, E911 had not yet been hooked into View 911, so the dispatcher had to query the database manually. In the most dramatic instance, a woman from another county called the Rappahannock sheriff to report that her sister, a county resident, had telephoned her and said she was being beaten by her husband. The woman didn't know her sister's address, but she knew the phone number. The dispatcher entered it into the system and found the address. Deputies interceded in the dispute.
      During the summer, a young boy called from a remote cabin to say he was alone and scared because his father had been away for several hours. Luckily, the child was able to give his last name which the dispatcher plugged into the system to find the cabin's location in the woods. A deputy waited with the boy until his father returned.
     Late in the summer, a light plane crashed deep in the woods of the nearby Shenandoah National Park. Once the crash site was identified from the air, Rappahannock's View 911 system was used to determine which route ground rescuers should take to get the scene.

Editing and GIS Capabilities
With the rapid growth underway throughout the county, new houses and roads are constantly under construction. Updating the database will be a constant process. The dispatch crew has been trained in both operating and editing functions. During off-peak hours, they will input new information.
      "The system has been equipped with an on-line editing function so that new features can be added directly to the digital basemap as if they were marked on the original topo maps," said Salmon. "The dispatcher needs about two hours training to use the system and about another two hours to learn the editing tools."
      At least four other county offices, including the county administrator's, will be equipped with View 911 terminals in the next 18 months to make use of its GIS functions, said John McCarthy.
      "The planning department will use it to decide where new roads must be built or widened, and the school board will add demographic information so that bus routes can be planned," he said. "We will add a security system to the database so that private information is not available to all offices."
      McCarthy laughed at the suggestion View 911 is a more robust system than a small county needs. "Rural counties have to be more responsive to growth because we have less money and less margin for error," he said. "We have to get it right the first time."

About the Author:
Kevin P. Corbley is director of Corbley Communications, which provides PR and marketing services to remote sensing, GIS and GPS firms. He is located in Denver, Colo., and may be reached at: telephone, 303-750-8011, or e-mail, [email protected]

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