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I Name 93flood Metadato date 1998 Feature Polygon Ori inator Federal Emergency Mana ement Agency The Q3 Flood Data are derived from the Flood Insurance Rate Maps ( FIRMS) published by the Federal Emergency Management Agency ( FEMA) . The file is georeferenced to the Description earth 's surface using the Universal Transverse Mercator ( UTMI projection and a zonal coordinate system (units in meters . Specifications for the horizontal control of Q3 Flood Data files are consistent with those required for mapping of a scale of 1 :24000. Purpose Purpose: The FIRM is the basis for floodplain management, mitigation, and insurance activities for the National Flood Insurance Program (NFIP) . Insurance applications include enforcement of the mandatory purchase requirement of the Flood Disaster Protection Act, which "requires the purchase of flood insurance by property owners who are being assisted by Federal programs or by Federally supervised, regulated, or insured agencies or institutions in the acquisition or improvement of land facilities located or to be located in identified areas having special flood hazards" (Section 2 ( b) � 4) of the 1973 Flood Disaster Protection Acts . In addition to the identification of Special Flood Hazard Areas (SFHAs) , the risk zones shown on the FIRMS are the basis for the establishment of premium rates for food insurance coverage offered through the NFIP. Q3 Flood Data files convey certain key features from the existing hard copy FIRM. Edge-matching errors, overlaps and deficiencies in coverage, and similar problems are not corrected during digitizing or post-processing . The Q3 Flood Data files are intended to provide users with automated flood risk data that may be used to locate SFHAs . More detailed information may be obtained from the paper FIRM . film a Period of Content Calendar Date: 1998 Status Progress : Complete Maintenance and Update Frequency: Irregular Contact Organization: Federal Emergency Management Agency, Mitigation Directorate ' Contact Address Address: 500 C Street, S.W . Point of Contact City: Washington State or Province: District of Columbia Postal Code: 20472 Contact voice Telephone: 1 -800-358-9616 Attribute Definitions Fips: County code, Long: Longitude Lit: Latitude State: State code etc . 03 Flood Data were produced by eithersconning and vectoraing or manually digitizing a hardcopy version of the graphic materials. The scanning and veciorizarion process captured the digital data os rosier data that were vectorfzed and attributed on an interactive editing station. The manual digitizing process used a digitizing fable to capfure the digital data; attribution was performed either as the data were digitized or on on Interactive edit station atter the digitizing was completed. The determination of the production methodology was based on various criteria, including availability of producrion systems. Four to nine control points per FIRM panel were used for registration during manual digitizing. A projective transformation was performed on the coordinates used in the data collection and editing systems to register the dig;toi data to the Universol Transverse Mercator (UTM) grid coordinates. An ARCINFO coverage of the Q3 Flood Data was Process Steps generated and used to create the 03-DLG file. The 03 Flood Data were checked for position and attribute accuracy by comparing plots of the digital data tothe source graphic and by symbolized display on an interactive computer system. Selected attributes that could not be visuaily verified were individually queried In addition, an ARCINFO Arc Macro Language (AivQ software progrom was applied to the dataset to test the attributes against a master set of valid attributes for the specific data category and o complete set of valid atinbute combinations. Source graphics were revised to reflect updates effected by Letters of Map Change (Leiferof Map Revision [LOMRJ, Letter of Map Amendment (LOMAJ) . These revisions were included in the Q3 Flood Data if they were mappable at the publication scale of the source graphic. Once final, the ARCiNFO coverage is projected into a geographic grid system, using decimal degree latitude and longitude coordinates and then converted into on ARCINFO Ex ort file. 6-28 GIS Needs Assessment and Implementation Plan Chapter 6 - Data Standards and Transfer