GIS helps with flood relief

Federal Emergency Management Agency maps Web site

Geographic information system (GIS) technology is giving federal and state emergency managers a better vantage point to direct their response to recent Mississippi River flooding.

The Federal Emergency Management Agency's Mapping and Analysis Center, using remote-sensing data delivered by the agency's Response and Recovery Directorate, has created several digital maps showing the extent of flooding and saturation in several communities along the Mississippi, as well as the number of people and houses affected.

The mapping center accesses GIS polygon files directly on its network, then creates maps based on what data layers are requested. For example, schools, hospitals and historic places can all be layered according to responders' needs, said Ed Corvi, acting team leader for FEMA's GIS and Internet Development Team.

The maps provide "a broad sweep of the picture," said Leslie Weiner-Leandro, the mapping center's lead geographer, which helps officials "get some understanding of how they need to prepare to respond."

Corvi said that the maps, posted on FEMA's Web site, helped FEMA Director Joe Allbaugh get a visual sense of the flood's extent before his visits to flooded communities last week.

State responders are using GIS extensively as well. When the Mississippi River breached a sandbag levy near LeClaire, Iowa, last week, state officials working at the emergency operations center in Des Moines used GIS software to display an elevation map of the region, enabling them to see the contours of the land along the river and to quickly get an idea of what direction the water would take and how much damage it might do.

The river maps not only show the channels but islands, some of which have houses that could be in danger, said Jake Freier, GIS coordinator for the Iowa Emergency Management Division. In the event of a breach, road maps will help center staff members determine road and bridge closings and plan detours.

As the waters recede in the coming week, the center also will use GIS to assess the damage. Staff members going out into the field will take Global Positioning System units with them to lock in coordinates for flooded properties.