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Summer 2007

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Flood Map Modernization at the U.S. Federal Emergency Management Agency

The U.S. Federal Emergency Management Agency (FEMA) manages federal response and recovery efforts after any national incident. In 2003, FEMA became part of the U.S. Department of Homeland Security (DHS). More than 2,600 full-time employees work at FEMA headquarters in Washington, D.C., and around the country. FEMA also has approximately 4,000 standby disaster assistance employees who are available for deployment after disasters.

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FEMA flood hazard maps are integrated with a GIS database that makes data available over the Internet.

FEMA initiates proactive mitigation activities, trains first responders, and manages the National Flood Insurance Program (NFIP). NFIP currently serves 4.5 million policyholders and provides coverage for $650 billion in insured assets to more than 19,700 communities.

Often, FEMA works in partnership with other organizations that are part of the nation's emergency management system. These partners include state and local emergency management agencies, federal agencies, and the American Red Cross.

The Challenge

FEMA developed a five-year plan, Flood Map Modernization (Map Mod), to update the NFIP's digital flood insurance rate maps (DFIRMs). DFIRMs depict potential flood hazard risk for communities throughout the United States and its territories. FEMA uses DFIRMs to delineate a community's special flood hazard areas and risk premium. Because flood hazard conditions are dynamic, DFIRM data needs to be continually updated. FEMA contracts with state, local, and regional mapping partners to keep flood hazard maps current and to produce maps. FEMA needed an integrated software solution that could manage these updates and changes.

The Solution

FEMA chose to manage data for the DFIRMs by integrating flood hazard maps with a GIS database that makes data available over the Internet. The tools used are based on Production Line Tool Set (PLTS) for ArcGIS, which was specifically developed for high-volume database production, maintenance, quality control (QC), and cartographic production projects such as this.

The development of DFIRMs begins with Job Tracking for ArcGIS (JTX), a workflow management application designed to improve the efficiency of multiuser GIS projects. Through Job Tracking for ArcGIS (JTX), FEMA mapping partners create flood hazard products by progressing through a FEMA-defined set of best practices workflow steps. The ability of Job Tracking for ArcGIS (JTX) to facilitate the assignment of work among users allows mapping partners to efficiently manage their DFIRM projects.

Many of the DFIRM workflow steps require the use of ArcMap, an application within ArcGIS Desktop, for data development and review. Upon launching ArcMap via Job Tracking for ArcGIS (JTX), the user can get the toolbars and layers necessary to perform FEMA-specific tasks. FEMA manages symbology requirements with Esri GIS Data ReViewer, which is part of PLTS for ArcGIS. GIS Data ReViewer allows users to employ a set of predefined complex attribute checks to review both spatial layers and business tables. These checks mimic FEMA's independent QC process because users can detect and correct errors early in the DFIRM production process. These checks also help ensure that FEMA-compliant data is created.

The GIS Data ReViewer Error Table tools allow different critics within the mapping partner group (including QC, engineering, and mapping) to review the spatial data. The engineers and QC analysts use notepad features and comments in the Error Table tools to indicate areas in need of revision, which the mapping analysts then correct. The GIS Data ReViewer Error Table tools also facilitate the spatial integration of engineering data.

The Results

FEMA is now able to easily track the mapping process for its flood hazard mapping projects and create the final DFIRM database through best practices using PLTS for ArcGIS. PLTS for ArcGIS streamlines the product development process and allows FEMA mapping partners to work together by project reassignment using Job Tracking for ArcGIS (JTX) within the DFIRM tools environment.

PLTS for ArcGIS also facilitates the spatial and attribute validation process. Using GIS Data ReViewer, FEMA can effectively highlight attribute errors. The GIS Data ReViewer Error Table tools allow QC analysts to locate areas in need of revision in the flood hazard database, track the mapping process of projects, and revise the database.

Once updated, DFIRMs are stored digitally on FEMA's Mapping Information Platform (MIP), which can be viewed on the agency's Web site at

More Information

For more information, contact Melis Mull, FEMA, Mitigation Division (tel.: 202-646-4135), or Jon Nystrom, Esri (e-mail:, tel.: 703-506-9515, ext. 8039).

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