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Summer 2002
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Dealing with a "Lake Effect" Snowstorm

Buffalo, New York, Uses GIS in Response to a Natural Emergency

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Map showing structures damaged during the December 2001 snowstorm.

Although other places receive more snow, Buffalo has earned a reputation for the occasional severe snowstorm. Located at the northeast end of Lake Erie, Buffalo is a prime target for "lake effect" snow. As the prevailing winds cross the lake, they pick up moisture and dump snow when the frigid air comes ashore. On Christmas Eve, December 24, 2001, a classic lake effect storm pounded Buffalo and the surrounding communities. This storm broke records not only because of the amount of snow but also because it marked the first time Erie County utilized GIS for emergency response. The County used GIS for tracking and communicating the status of street conditions and storm-damaged structures and to inventory snow-dumping locations, as well as maintain a map history of the response effort.

A Seven-Foot Snowfall

Even though the residents of Buffalo and Erie County are accustomed to dealing with significant amounts of snow, a seven-foot snowfall presents an enormous challenge. Fortunately the storm began Christmas Eve. Schools were not in session, and many people were off work. These two facts spared the area from a real disaster. Stranded students and many more stranded motorists would have seriously complicated a bad situation.

By the afternoon of December 28, it was clear this was no longer a snowplowing effort--it became a snow-removal effort. Six to seven feet of snow clogged roadways and collapsed roofs and even entire structures. Abandoned vehicles made roads impassable. Snowplows could not function in many areas. Neighborhood streets, and everything on them, disappeared under the snow. Travel bans went into effect throughout the region. In Buffalo, more than 70 percent of the streets were either totally impassable or had only one lane open.

Applying GIS to the Emergency

The magnitude of the snowstorm drew assistance from the National Guard, neighboring counties, even crews from Toronto, Canada. When coupled with the local highway crews, there was a lot of equipment available--the problem was where to deploy it. The County established an Emergency Operations Center (EOC) to coordinate the efforts.

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Streets Management System, an ArcView extension.

The New York State Department of Transportation (NYSDOT) set up shop at the EOC. While NYSDOT typically uses a five-level rating system for evaluating highway conditions, the decision was made to use just three levels for this emergency. Roads were color coded

  • Red for impassable
  • Yellow for one-lane passable
  • Green for two lanes open

The EOC sent out road assessment teams on four-hour shifts with paper maps and color markers to record road conditions and to report back to the EOC.

EOC officials called the Erie County Office of Geographic Information Services to assemble a GIS operation at the EOC. Within hours, the office moved three computers, a large-format plotter, and a printer to the EOC. GIS personnel from several local public agencies and private firms were brought in to the EOC, in some cases by the National Guard in Humvees.

This rapid response was due to a fortunate turn of events. Just weeks preceding the snowstorm, the GIS Resource Group of D'Alba & Donovan GIS Consultants (Williamsville, New York), an Esri Business Partner, and Mark Harris of GeoSnap (Lackawanna, New York) developed a Streets Management System for the City of Buffalo. This ArcView extension allowed users to rapidly assign a status (open, closed, restricted) and an explanation (construction, parades, plowing, etc.) to selected streets. Users could select individual street segments or draw polygons to select large groupings of segments. The group modified the tool to accept the NYSDOT red, yellow, and green road status, and the GIS was operational.

Using the Streets Management System, GIS staff entered the NYSDOT assessment team data into the GIS and calculated the total miles of road in each category. The EOC sent the teams back out with fresh maps to continually reassess the conditions. With each update, NYSDOT, County, and City officials directed plow crews to the areas in need. This interaction between the ArcView application and road assessment teams continued 24 hours a day for the first five days.

To help the crews haul the snow away, locations of snow dumpsites were entered into ArcView. This information was especially useful to out-of-town crews unfamiliar with the local streets.

As damage reports came into the EOC from local emergency response officials, building locations were geocoded to display collapsed, damaged, or hazardous conditions (gas leaks, no heat, etc.).

A complete history of the response efforts was mapped in ArcView. Plots were produced every five to seven hours and posted on the EOC walls. At the same time, PDFs were generated and posted on the Web for public officials. The resulting maps became part of the record reviewed by the Federal Emergency Management Agency (FEMA). While not yet final, local officials have estimated the cost of the snowstorm in excess of $30 million.

Lessons Learned

This experience underscored some important points.

  • Staffing is critical--Maintaining a 24-hour GIS operation is exhausting. Access to experienced ArcView users, whether on staff, loaned, or volunteers, was essential. A local ArcInfo/ArcView user group may be a valuable source to tap during an emergency.
  • The infrastructure for an emergency GIS operation should be in place beforehand--While a permanent GIS reserved for emergency operations is not cost effective, lists should be maintained of what is needed and where items such as routers, cables, computers, plotters, printers, and even power strips are located.
  • Handheld devices running ArcPad would eliminate redundant data entry and improve accuracy--Customized ArcPad applications, now available in ArcPad 6, will be developed for future events. Wireless communications is the goal.
  • Standardized forms for collection of building conditions and guidelines with visual examples are necessary--This would ensure consistency of the data for the road and building assessment teams.
  • CDs containing recent parcel information, local street data (suitable for geocoding and routing), and aerial photography should be made before an emergency--This would eliminate the need to hunt for data under pressure and save critical time.
  • While the PDF files worked, an ArcIMS solution would have been better--At the time of this snowstorm, the Erie County Office of Geographic Information Services was creating an Internet Mapping Cooperative among local governments. As this ArcIMS-based initiative takes shape over the next several months, it will become essential to the County's emergency response efforts.


ArcView proved to be a valuable tool that contributed greatly to the response efforts. According to Erie County Emergency Services Commissioner Michael Walters, "GIS was essential for helping to manage the various resources used in the response effort. The follow-up to any emergency is securing funding from the Federal Emergency Management Agency. The record of the storm's cleanup that was provided by GIS was a major factor in gaining a disaster declaration."

Many were surprised at how quickly the staff could generate updated maps and how useful this information proved to be in the response effort. Further evidence of the acceptance of GIS during this event were the lines of individuals waiting to request updated or special interest maps.

For more information, contact Graham S. Hayes (tel.: 716-667-6608, e-mail:, and Dale J. Morris, director of the Erie County Office of Geographic Information Services (tel.: 716-858-7422, e-mail:

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