Q3 FLOOD DATA SPECIFICATIONS DRAFT May 1998 TRADEMARKS ARC/INFO, ArcView, ArcCAD, ARC Macro Language (AML), and ARC/INFO LIBRARIAN are trademarks of Environmental Systems Research Institute, Inc., Redlands, CA. AutoCAD is a trademark of AutoDesk, Inc, San Rafael, CA. EIS is a trademark of Emergency Information Systems International, Rockville, MD. GENAMAP is a trademark of GenaSys, Fort Collins, CO. MapInfo and ArcLink are trademarks of MapInfo Corporation, Troy, NY. MGE GIS Translator is a trademark of Intergraph Corporation, Huntsville, AL. MicroStation is a trademark of Bentley Systems, Inc., Exton, PA. TABLE OF CONTENTS Introduction . . . . . . . . . . . . . . . . . . v Part 1 BACKGROUND . . . . . . . . . . . . . . . 1 History of the National Flood Insurance Program1 Automation of NFIP Mapping. . . . . . . . . 2 Q3 Flood Data Product History . . . . . . . 2 Future of NFIP Digital FIRM Products. . . . 3 Part 2 NFIP DIGITAL FIRM PRODUCTS AND THEIR APPLICATIONS5 Digital Flood Insurance Rate Map (DFIRM). . 5 Q3 Flood Data . . . . . . . . . . . . . . . 6 Part 3 Q3 FLOOD DATA QUALITY. . . . . . . . . .11 Attribute Accuracy. . . . . . . . . . . . .11 Topology. . . . . . . . . . . . . . . . . .11 Logical Consistency . . . . . . . . . . . .11 Completeness. . . . . . . . . . . . . . . .12 Currentness . . . . . . . . . . . . . . . .12 Part 4 USE POLICY . . . . . . . . . . . . . . .13 Standards of Care . . . . . . . . . . . . .13 Community Rating System . . . . . . . . . .13 Flood Determinations. . . . . . . . . . . .14 The "Good Faith Standard" . . . . . . . . .14 Use of Q3 Coastal Barrier Resources System Data16 Part 5 Q3 FLOOD DATA DISTRIBUTION . . . . . . .17 Available Formats . . . . . . . . . . . . .17 Conversion to Other GIS Formats . . . . . .18 Projections . . . . . . . . . . . . . . . .19 File Naming . . . . . . . . . . . . . . . .19 Ordering Instructions . . . . . . . . . . .19 Data Organization . . . . . . . . . . . . .20 User Support. . . . . . . . . . . . . . . .21 Q3 Flood Data Counties. . . . . . . . . . .21 Revisions/Updates . . . . . . . . . . . . .21 Part 6 FEMA'S USES OF Q3 FLOOD DATA . . . . . .23 Objective . . . . . . . . . . . . . . . . .23 SFHA Library Themes . . . . . . . . . . . .24 Deliverables. . . . . . . . . . . . . . . .25 FEMA's GIS Environment. . . . . . . . . . .25 Q3 Flood Data Tiling Structure. . . . . . .26 Data Storage Requirements . . . . . . . . .26 SFHA Library Directory Structure. . . . . .26 Part 7 VECTOR Q3 FLOOD DATA SPECIFICATIONS. . .29 Definition. . . . . . . . . . . . . . . . .29 Data Capture Methods. . . . . . . . . . . .30 Horizontal Control. . . . . . . . . . . . .30 Tiling. . . . . . . . . . . . . . . . . . .30 Data Sources. . . . . . . . . . . . . . . .30 Attribute Information . . . . . . . . . . .31 Part 8 Q3 FLOOD DATA ARC/INFO COVERAGE SPECIFICATIONS35 Projection/Coordinate System. . . . . . . .35 Tolerances/Precision. . . . . . . . . . . .35 File Naming . . . . . . . . . . . . . . . .35 Attribute Definition. . . . . . . . . . . .36 Part 9 Q3 FLOOD DATA MAPINFO FILE SPECIFICATIONS49 Projection/Coordinate System. . . . . . . .49 Tolerances/Precision. . . . . . . . . . . .49 File Naming . . . . . . . . . . . . . . . .50 Attribute Definition. . . . . . . . . . . .50 Part 10 Q3 FLOOD DATA DLG SPECIFICATIONS. . . .53 Projection/Coordinate System. . . . . . . .53 Tolerances/Precision. . . . . . . . . . . .53 File Naming . . . . . . . . . . . . . . . .54 Digital Line Graph Structure. . . . . . . .54 File Header Information . . . . . . . . . .59 Data Record Information . . . . . . . . . .63 Attribute Definition. . . . . . . . . . . .63 Part 11 Q3 FLOOD DATA METADATA SPECIFICATIONS .75 Why Metadata? . . . . . . . . . . . . . . .75 Q3 Flood Data Metadata Description. . . . .76 Metadata File Naming. . . . . . . . . . . .76 Non-Standard Q3 Flood Data Metadata Entry Definition77 APPENDIX A - Sample Q3 Flood Data ARC/INFO Coverage MetadataA-1 APPENDIX B - Sample Q3 Flood Data MapInfo File MetadataB-1 APPENDIX C - Sample Q3 Flood Data DLG Metadata C-1 APPENDIX D - UTM Zones . . . . . . . . . . . . D-1 APPENDIX E - Glossary. . . . . . . . . . . . . E-1 REFERENCES LIST OF FIGURES Figure 1 DFIRM and Q3 Flood Data Contents. . 8 Figure 2 DFIRM and Q3 Flood Data Characteristics9 Figure 3 File Format Comparison. . . . . . .18 Figure 4 Q3 Flood Data Product Formats . . .20 Figure 5 SFHA Data Library Thematic Layers .24 Figure 6 SFHA Data Library Storage Estimates26 Figure 7 FEMA SFHA Data Library Diagram. . .27 Figure 8 Q3 Flood Data ARC/INFO Coverage Attribute Definition37 Figure 9 Q3 Flood Data ARC/INFO Coverage SFHA Zone Definition40 Figure 10 Q3 Flood Data ARC/INFO Coverage Floodway Area Definition43 Figure 11 Q3 Flood Data ARC/INFO Coverage Coastal Barrier Resources System Area Definition. . . . . . . . . . . .44 Figure 12 Q3 Flood Data ARC/INFO Coverage FIRM Panel Type Definition . . . . . . . . . . . . . . . . . . .45 Figure 13 Q3 Flood Data ARC/INFO Coverage Polygon Shades 46 Figure 14 Q3 Flood Data ARC/INFO Coverage Attribute Combinations47 Figure 15 ARC/INFO to MapInfo Feature Translation51 Figure 16 Q3-DLG Attribute Coding . . . . . .65 Figure 17 Q3-DLG Attribute Code Domain. . . .73 INTRODUCTION This document is intended to provide users of Q3 Flood Data with detailed information regarding the contents of the Q3 Flood Data files. An overview of the Q3 Flood Data product may be found in the Q3 Flood Data Users Guide. This document is presented in seven main parts. They are: 1. Background - This section summarizes the history of the National Flood Insurance Program (NFIP), the automation of its mapping program, the Q3 Flood Data product, and the future of NFIP digital Flood Insurance Rate Map (FIRM) products. 2. NFIP Digital FIRM Products and Their Applications - This section compares the contents and applications of the Federal Emergency Management Agency's (FEMA's) two digital FIRM products, the Digital Flood Insurance Rate Map (DFIRM) and the Q3 Flood Data. 3. Q3 Flood Data Quality - This section presents an overview of the quality of the Q3 Flood Data files with information about their attribute accuracy, topology, logical consistency, completeness, and currency. 4. Use Policy - This section presents FEMA's use policy regarding the Q3 Flood Data. It provides separate policy statements for standards of care, Community Rating System, and flood determination uses, explains the "Good Faith Standard," and provides guidance on the use of Coastal Barrier Resources System data. 5. Q3 Flood Data Distribution - This section discusses distribution issues including available file formats, conversion to other Geographic Information System (GIS) formats, map projections for the various formats, file naming conventions, ordering instructions, organization of the Q3 Flood Data, user support, the Q3 Flood Data counties, and FEMA's revision/update plans for the Q3 Flood Data. 6. FEMA's Uses of Q3 Flood Data - This section describes FEMA's in-house uses of the Q3 Flood Data within the context of the Special Flood Hazard Area (SFHA) Data Library. It presents the objectives, data themes, deliverables, GIS environment, Q3 Flood Data tiling structure, storage requirements, and directory structure of the SFHA Data Library. 7. Vector Q3 Flood Data Specifications - This section presents information that is common to the three vector file formats of Q3 Flood Data: the vector file definition, data capture methods, horizontal control, tiling, data sources, and attribute information. 8. Q3 Flood Data ARC/INFO Coverage Specifications - This section presents the specifications for the vector Q3 Flood Data in ARC/INFO format but discusses only items that differ between vector file formats. (Items common to all vector formats are discussed in Part 7, the Vector Q3 Flood Data Specifications.) These items are the projection, coordinate system, tolerances, precision, file naming, and attribute definition of the Q3 Flood Data ARC/INFO coverages. 9. Q3 Flood Data MapInfo File Specifications - This section presents the specifications for the vector Q3 Flood Data in MapInfo format but discusses only items that differ between vector file formats. (Items common to all vector formats are discussed in Part 7, the Vector Q3 Flood Data Specifications.) These items are the projection, coordinate system, tolerances, precision, file naming, and attribute definition of the Q3 Flood Data MapInfo files. 10. Q3 Flood Data DLG Specifications - This section presents the specifications for the vector Q3 Flood Data in Digital Line Graph (DLG) format but discusses only items that differ between vector file formats. (Items common to all vector formats are discussed in Part 7, the Vector Q3 Flood Data Specifications.) These items are the projection, coordinate system, tolerances, precision, file naming, DLG structure, file header information, data record information, and attribute definition of the Q3 Flood Data DLG files. 11. Q3 Flood Data Metadata Specifications - This section presents an overview of FEMA's Metadata requirements. It explains the importance of metadata, describes the Q3 Flood Data metadata, tells how the metadata files are named, and gives definitions for non-standard metadata entries. 12. Appendices - These include three sample metadata files, a listing of the Universal Transverse Mercator (UTM) zones, and a glossary of terms and acronyms. Part 1 BACKGROUND This section summarizes the history of the National Flood Insurance Program, the automation of its mapping program, the Q3 Flood Data product, and the future of NFIP digital FIRM products. History of the National Flood Insurance Program In response to increasing losses from flood hazards nationwide, the Congress of the United States passed the National Flood Insurance Act of 1968 which established the National Flood Insurance Program (NFIP). The 1968 Act provided for the availability of flood insurance within communities that were willing to adopt floodplain management programs to mitigate future flood losses. The act also required the identification of all floodplain areas within the United States and the establishment of flood-risk zones within those areas. As a result of the 1972 Hurricane Agnes flooding along the East coast, the 1968 Act was expanded by the Flood Disaster Protection Act of 1973. The 1973 Act added the mandatory purchase requirement and increased the awareness of floodplain mapping needs throughout the country. The responsibility for administration of the NFIP falls with the Federal Insurance Administration of the Federal Emergency Management Agency (FEMA). The risk data to identify floodplain areas, as required by the Act, are acquired through Flood Insurance Studies (FISs). FISs are hydrologic and hydraulic studies of flood risks developed by FEMA. Using the results of a FIS, FEMA prepares a Flood Insurance Rate Map (FIRM) that depicts the spatial extent of Special Flood Hazard Areas (SFHAs) and other thematic features related to flood risk assessment. SFHAs are areas subject to inundation by a flood having a one-percent or greater probability of being equaled or exceeded during any given year. This flood, which is referred to as the 1% annual chance flood (or base flood), is the national standard on which the floodplain management and insurance requirements of the NFIP are based. FEMA publishes the FIRM and distributes it to a wide range of users: private citizens, community officials, insurance agents and brokers, lending institutions, and other Federal agencies. The FIRM is the basis for floodplain management, mitigation, and insurance activities of the NFIP. Uses of the FIRM for insurance activities include enforcement of the mandatory purchase requirement of the 1973 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 or facilities located or to be located in identified areas having special flood hazards" (Section 2(b)(4) of the 1973 Act). In addition to the identification of SFHAs, the risk zones shown on the FIRMs are the basis for the establishment of premium rates for flood coverage offered through the NFIP. At present, FISs have been completed and FIRMs published for virtually all communities in the nation having flood risks. Flood risks have been assessed in approximately 20,400 communities nationwide. These studies, conducted at a cost of over $900 million, have resulted in the publication of over 80,000 individual FIRM panels. Typically, 6 to 8 million FIRMs are distributed to users each year by FEMA. Over 2.5 million flood insurance policies have been written through the NFIP, providing coverage against flood loss for over $200 billion in property nationwide. In addition to initial FISs, FEMA is responsible for maintaining the FIRMs as communities grow, as new or better scientific and technical data concerning flood risks becomes available, and as some FISs become outdated by the construction of flood control projects or the urbanization of rural watersheds. Several thousand FIRMs need to be updated per year. Automation of NFIP Mapping Developments in the fields of automated cartography and Geographic Information Systems (GIS) technology led FEMA to study the potential of automating NFIP mapping and engineering. After a series of technology assessment and pilot projects, FEMA concluded that existing technology made the automation of NFIP mapping and engineering feasible. In Fiscal Year 1992, FEMA implemented a ten-year automation program, beginning with the conversion of FIRMs to a digital format. Q3 Flood Data Product History Starting with Hurricane Hugo in 1989, FEMA has attempted to support disaster relief operations with digital FIRMs. Disaster loan closings by the Small Business Administration (SBA), Temporary Housing Programs, and Individual Assistance and Family Grant Programs all require a flood hazard assessment. With automated flood map reading to support these assessments, significant time can be saved and map reading quality improved, thus resulting in faster disaster relief for victims. More recently, increased funding for post-disaster mitigation activities has led to the extensive use of GIS and digital FIRMs for planning activities. Applications include selection of sites for relocation, prioritizing eligibility for home buyout programs, and identifying repeatedly damaged properties in SFHAs. To support disaster recovery operations, FEMA has developed specifications for a digital product named the Q3 Flood Data. This product has the advantage of being far less costly in time and resources to produce than FEMA's other digital FIRM product, the Digital Flood Insurance Rate Map (DFIRM). The Q3 Flood Data product is designed to serve FEMA's Response and Recovery activities as well as flood insurance policy marketing initiatives. This product is designed to allow rapid access to and distribution of digital FIRM data, and is compatible with all existing digital FIRM data already available and underway. Future of NFIP Digital FIRM Products Digital Line Graph Level 3 (DLG3) was adopted by FEMA as the appropriate data model for the distribution and storage of digital FIRM products. DLG3 shall function as FEMA's data distribution format until specifications for data distribution that meet Spatial Data Transfer Standards (SDTS) (FIPS 173) can be implemented. Many software vendors have implemented, or are in the process of implementing, SDTS translators. With development continuing on all aspects of these data models, immediate application of the SDTS is not feasible. FEMA plans to adopt the SDTS standards for distribution of its geospatial digital data in compliance with the Federal standards, when development of appropriate specifications and mechanisms have been finalized. Part 2 NFIP DIGITAL FIRM PRODUCTS AND THEIR APPLICATIONS This section compares the contents and applications of FEMA's two digital FIRM products, the Digital Flood Insurance Rate Map (DFIRM) and the Q3 Flood Data. The conversion of FIRMs to a digital format is expected to have many benefits. However, users must bear in mind that the simple conversion of FIRMs to a digital format does not inherently improve the engineering quality of the product. Many of the same difficulties with interpretation of flood risk data remain unchanged, as does the requirement to use sound judgment in selecting methods for decision making and map interpretation. FEMA distributes digital FIRM data in two basic product levels. These are the DFIRM (including the hardcopy DFIRM and the DFIRM-DLG) and the Q3 Flood Data. These two products differ in their contents, quality, and intended use. Digital Flood Insurance Rate Map (DFIRM) DFIRM Contents The DFIRM is comprised of all digital data required to create the hardcopy FIRM. This includes base map information, graphics, text, shading, and other geographic and graphic data required to create the final hardcopy FIRM product to FEMA standards and specifications (see the Standards for Digital Flood Insurance Rate Maps, Reference 1). This product serves the purpose of map design and provides the database from which the DLG thematic product of the flood risks is extracted to create the DFIRM-DLG. This product is generally produced in a countywide format. DFIRMs are subjected to community review and approval and are, therefore, the official basis for implementing the regulations and requirements of the NFIP within the community. Specifications for digitizing DFIRMs are consistent with those required for mapping at a scale of 1:24,000, or larger. The DFIRM-DLGs are created by extracting only the flood risk thematic data from the DFIRM. The format of this product is the U.S. Geological Survey Digital Line Graph Level 3 Optional format, as described in the Standards for Digital Flood Insurance Rate Maps. The DFIRM-DLG does not include base map information, nor does it include graphic data required to create a hardcopy FIRM. This product is intended to be the primary means of transferring flood risk data depicted by FIRMs to GISs through a public domain data exchange format. The DFIRM-DLGs are tiled to the U.S. Geological Survey 1:24,000 scale topographic map series. DFIRM Applications The hardcopy DFIRM replaces the hardcopy FIRM as the official basis for implementing the regulations and requirements of the NFIP within the community. The DFIRM-DLG thematic data is simply a digital version of the hardcopy DFIRM. Thus, any revisions, appeals, or other requests for changes to DFIRMs can be made under the same mechanisms as those developed for the hardcopy format FIRMs. The only change the DFIRM-DLG represents is the format of the data. Existing NFIP regulations and procedures are not impacted by this change. However, the end user does have the option of submitting requests for revisions to FEMA in a digital format. With increasing frequency, highly detailed large scale digital mapping is becoming available. DFIRMs may utilize this data as a source (new engineering data collected using photogrammetric techniques) or as a base map. Communities whose digital base mapping files were utilized as the base map for the DFIRM will find that they may use the DFIRM-DLG files for all determination and enforcement regulations. Q3 Flood Data Q3 Flood Data Contents Q3 Flood Data are developed by scanning the existing hardcopy FIRM and vectorizing a thematic overlay of flood risks. Vector Q3 Flood Data files contain only certain features from the existing hardcopy FIRM. The features contained in the vector Q3 Flood Data files include the following:  1% and 0.2% annual chance floodplain areas, including Zone V areas, certain floodway areas, and zone designations;  Coastal Barrier Resources System (CBRS) areas;  political areas, including community identification number;  FIRM panel areas, including panel number and suffix;  7.5-minute quadrangle areas; and  mappable Letters of Map Change (LOMCs). Sources that reflect updates effected by Letters of Map Change (Letter of Map Revision, Letter of Map Amendment) are utilized in the preparation of vector Q3 Flood Data files. These revisions are included in the vector Q3 Flood Data if they are mappable at the publication scale of the source graphic. The vector Q3 Flood Data files do NOT include the following:  base map data (streets, etc.);  base flood elevation lines and elevations;  cross sections and letter identifiers;  elevation reference marks and their elevations;  floodways if not shown on the FIRM;  internal boundaries of contiguous CBRS areas; and  prohibition dates associated with individual CBRS areas. Edge-matching errors, overlaps and underlaps in coverage, and similar problems are not corrected during digitizing or scanning and vectorizing. The hardcopy FIRMs from which the vector Q3 Flood Data are extracted contain no horizontal control. The specifications for the horizontal control of Q3 Flood Data vector data are consistent with those required for mapping at the scale of 1:24,000. The horizontal controlling of these data is typically performed by fitting the vectors to a georeferenced raster 7.5-minute quadrangle file. The raster files generated by scanning the hardcopy FIRMs are not georeferenced. The vector Q3 Flood Data are contained in one single countywide file, including all incorporated and unincorporated areas of a county. The feature items and attributes are defined in detail later in this document. The means for linking other associated NFIP data to these files can be derived from the attributes contained within the files. For instance, the currently effective FIRM panel from the Community Status Book (Reference 2) or the Flood Map Status Information System can be compared to the FIRM panel information in the Q3 Flood Data files to determine if the Q3 Flood Data files reflect the most current mapping. Q3 Flood Data Applications The Q3 Flood Data do not replace the existing hardcopy FIRM or, if one exists, DFIRM product. The product has been designed to support planning activities, some Community Rating System (CRS) activities, insurance marketing, and mortgage portfolio review. It does not provide base flood elevation information; thus, it has limited application for engineering analysis, particularly for site design or rating of flood insurance policies for properties located within SFHAs. Vector Q3 Flood Data are not tied to a base map, are not used to produce a new version of the hardcopy FIRM, and are not subjected to community review. Q3 Flood Data are intended to provide users with automated flood risk data suitable for determining whether features are within or outside the SFHA. The vector Q3 Flood Data product can be a valuable tool to assist in screening property addresses within a GIS to determine flood risks. However, as the geographic processing performed to develop the Q3 Flood Data may introduce differences with the source hardcopy FIRMs, users must apply considerable care and judgment in the application of this product. For instance, the Q3 Flood Data may be overlaid on highly detailed large scale community base mapping data, but, if parcel level determinations are made, they must be prefaced with information about the accuracy of the data from which they are derived. The following two tables (Figures 1 and 2) compare the contents of the DFIRM and Q3 Flood Data files. DFIRM and Q3 Flood Data Contents DFIRM DFIRM-DLG Vector Q3 Flood Data 1% Annual Chance Floodplain Boundary û û û 0.2% Annual Chance Floodplain Boundary û û û Floodway û û Some Gutters (Zone Breaks) û û û Political Boundaries û û û FIRM Neatline û û û Quad Neatline û û LOMCs û û û Coastal Barrier Resources System areas û û Outer boundary only Base Flood Elevations û û Cross Sections û û Elevation Reference Marks û û Base Map (Streets, etc.) û Figure 1 DFIRM and Q3 Flood Data Characteristics DFIRM DFIRM-DLG Vector Q3 Flood Data Tiling FIRM panel 7.5' quad County Number of Thematic Layers --- 4 1 Line Attributes? --- Yes No Area Attributes? --- Yes Yes Attributes --- Variable Fixed Recommended Buffer --- 50' 250' Horizontal Accuracy FIRM scale FIRM scale 1:24,000 Engineering Use Recommended? Yes Yes No Community Review? Yes Yes No Figure 2 Part 3 Q3 FLOOD DATA QUALITY This section presents an overview of the quality of the Q3 Flood Data files. It provides information about their attribute accuracy, topology, logical consistency, completeness, and currency. Although FEMA has established no independent quality control/quality assurance program for the Q3 Flood Data, the Q3 Flood Data files are distributed only after they have passed checking routines contained in FEMA's Q3 Quality Assurance (Q3QA) Checking Software. The data are accompanied by documentation showing that the files have been evaluated and passed. FEMA has established a User Support mechanism through which any problems found with the data can be identified and channeled back to FEMA for resolution. Attribute Accuracy The attribute accuracy of the Q3 Flood Data vector files is tested by manual comparison of source FIRM with hardcopy plots and a symbolized display on an interactive computer graphic system. Selected attributes that cannot be visually verified are individually queried. In addition, FEMA's Q3QA Checking Software program is applied to the dataset to test the attributes against a master set of valid attributes and attribute combinations. Topology Polygon and line topology are present in Q3 Flood Data vector files. Certain node-area-line relationships are collected or generated to satisfy topological requirements, including the following:  lines begin and end at nodes;  lines connect to each other at nodes;  lines do not extend through nodes;  left and right areas are defined for each line segment and are consistent throughout the files; and  the lines representing the limits of the file neatlines are free of gaps. Logical Consistency Tests of logical consistency are performed by ARC/INFO software modules. Check plots are made to test for closure of all internal polygons. Completeness Data completeness for Q3 Flood Data files reflect the content and completeness of the source FIRM. Features may have been eliminated or generalized on the FIRM due to scale and legibility constraints. Edge-matching errors, overlaps and underlaps in coverage, and similar problems are not corrected during digitizing or scanning and vectorizing the Q3 Flood Data. The flood risk data presented in the FIRM are developed only for communities participating in the NFIP for use in insurance rating and for floodplain management. Flood hazard areas are determined using the following sources:  statistical analysis of records of river flow, storm tides, and rainfall;  information obtained through consultation with the communities;  floodplain topographic surveys; and  hydrologic and hydraulic analyses. Both detailed and approximate hydrologic and hydraulic analyses are employed. Generally, detailed analyses are used to generate flood risk data for developed or developing areas of communities. For undeveloped areas where little or no development is expected to occur, FEMA uses approximate analyses to generate flood risk data. Typically, only drainage areas that are greater than one square mile are studied. Currentness Flood Insurance Rate Maps continually undergo revisions and updates. Some of these revisions are effected by letter (Letter of Map Change). Q3 Flood Data may not reflect the most current information or information that is not mappable at the published scale of the FIRM. Users who need these updates should contact FEMA to obtain them in hardcopy format. To determine if the Q3 Flood Data files contain the most current map information, users may compare the FIRM publication date contained in the source information section of the Q3 Flood Data metadata file to the date listed in FEMA's Community Status Book for that community. If the Community Status Book lists a more recent map date, users may contact FEMA's Map Service Center to obtain copies of the newer maps. Part 4 USE POLICY This section presents FEMA's use policy regarding the Q3 Flood Data. It provides separate policy statements for standards of care, Community Rating System, and flood determination uses, explains the "Good Faith Standard," and provides guidance on the use of CBRS data. Standards of Care For the development of applications using the Q3 Flood Data, the user has the following responsibilities:  to obtain and review the technical documentation of the Q3 Flood Data, with particular regard to the limitation of this product;  to establish minimum mapping and accuracy standards required for the proposed application;  to obtain digital base maps and ancillary data of appropriate scale, resolution, and accuracy to support the applications; and  to determine whether Q3 Flood Data is based on the currently effective FIRM panel. The quality, accuracy, and reasonableness of any applications developed using Q3 Flood Data are the sole responsibility of the end-user. The Q3 Flood Data product is not suitable for engineering applications such as detailed site design and development plans, Letters of Map Change, or submittal of FIRM Map Revisions. Community Rating System For the purposes of the Community Rating System (CRS), Q3 Flood Data may be used in the following ways:  for calculations of SFHA areas and similar applications that require geographic calculations and measures;  for partial fulfillment of GIS provisions per the provisions of Section 440, "Flood Data Maintenance," as described in the National Flood Insurance Program Community Rating System Coordinator's Manual (Reference 3); and  for development of "notification" lists of potentially flood-prone properties, per the provisions of Section 330; and  for partial fulfillment of credits for the performance of flood determinations, when performed in conformance with guidelines for determination presented below. Flood Determinations The Q3 Flood Data can support flood determinations in a limited fashion, in conformance with the "Good Faith" standard, if used within the following guidelines:  The end user has obtained a source of address or property location data and combined it with Q3 Flood Data in a manner that conforms to the Standards of Care outlined above.  The end user has made no determinations as to the flood prone status of a property that is within 250 feet of an SFHA boundary. This requirement is due to the accuracy, resolution, and variations of the Q3 Flood Data relative to the source FIRMs.  The end user has verified that the Q3 Flood Data FIRM panel and suffix conform to the panel and suffix of the currently effective FIRM.  The end user has confirmed the availability of flood insurance in the community for which the determination is to be offered.  The end user has confirmed the zone and BFE with the source FIRM or DFIRM for properties located within 250 feet of the SFHA boundary or within the SFHA. The "Good Faith Standard" The mandatory flood insurance purchase requirements of the 1973 National Flood Insurance Act apply only when a structure is located in an SFHA in a community that is participating in the NFIP. Such a structure must be insurable under the rules of the NFIP. Even though a portion of the land parcel upon which the structure is planned or built may be within an SFHA, the mandatory purchase requirement is triggered only if the structure itself is within an SFHA. The compliance of lenders with the mandatory flood insurance purchase requirements of the 1973 Act is based on the "good faith standard." Determining whether a structure is located in an area of special flood hazard requires the examination of the location of the structure in relationship to the areas of special flood hazard as shown on the applicable FIRM. The good faith standard recognizes that despite FEMA's best efforts to make the FIRMs as useful as possible, the descriptions of SFHA areas, as depicted by some maps, may, in some instances, not be clear enough to permit lenders to decide with certainty and precision whether or not property that is the security for a loan or that is the subject of financial assistance is located in such an area. It is for this reason that FEMA has recommended a "good faith standard." The good faith standard requires lenders to exercise "due diligence and good faith" in determining the location of a property that is the subject of a loan relative to areas of special flood hazards as shown on a FIRM. This guidance is further explained, with additional information on the 1973 Act, in the publication Mandatory Purchase of Flood Insurance Guidelines (Reference 4). When determinations are being made by lenders, or firms or individuals retained by lenders to assist in these endeavors, collateral data in addition to the FIRM is frequently required. FIRMs do not include all roads within communities, nor do they depict address, property boundary, or structure location information. As a result, determinations frequently can be made only by using an ancillary source of data, such as a land parcel map, to determine the location of a property on the FIRM. Digital address range data, land parcel, and structure information is available for many communities across the nation. Using these digital data and GIS technology, it is possible to make determinations relative to the 1973 Act and meet the good faith standard. However, the lenders must assure that due diligence and good faith are exercised in application of digital mapping systems to make determinations. Because of both the increased complexity and analytical capabilities of GIS, assuring compliance with the good faith standard may require additional effort relative to use of paper maps. A prime concern is to assure that the accuracy of the digital base map and structure location data are appropriate for use with the chosen digital FIRM data set (DFIRM or Q3 Flood Data) to make determinations relative to the 1973 Act. The concern for accuracy of the ancillary data used with DFIRMs should increase in direct proportion to the relative closeness of the property under analysis to the SFHA boundary. Thus, lenders might not find it prudent to use digital data at the 1:100,000 scale as the primary source of information upon which to make a determination regarding a property located within 250 feet of an SFHA. Such caveats should be carefully considered when U.S. Bureau of the Census TIGER data are used as the source from which property determinations will be made. In some instances, GIS technology will enable the use of large-scale land parcel, topographic, structure, and other information, with digital FIRM data to make determinations. GIS technology allows maps to be created at any user-specified scale. Enlargement of scales does allow for precise determinations to be made. However, precise measurements are not inherently accurate. Accuracy can only be assessed from an appraisal of the quality of source data. SFHA boundary information conveyed by Q3 Flood Data files was developed to overlay USGS 7.5-minute topographic maps at a scale of 1:24,000. Thus, Q3 Flood Data cannot be assumed to have an accuracy of better than 40 feet. Due to other limitations, FIA recommends that determinations using GIS technology and Q3 Flood Data generally be made only when structures are located 250 or more feet outside an SFHA boundary. In cases where the structure is within 250 feet of the SFHA or inside the SFHA, data such as the Base Flood Elevation (BFE) determined from a FIS flood profile and the surveyed lowest adjacent grade and/or lowest floor elevation should be used to make a determination. Prudence may require that a more conservative margin than 250 feet be used to determine the need for ancillary data to support a GIS determination. Terrain variations, the nature of flood hazards in the area, and the quality of all digital data being used to make the determination should be considered when establishing the need for collecting survey and flood profile data. Use of Q3 Coastal Barrier Resources System Data The CBRS data presented within the Q3 Flood Data files carry the same limitations and use-restrictions as the floodplain boundary data. Because the CBRS data were captured from FIRMs that, in all likelyhood utilized an older public domain base map than what today's users will be using with Q3 Flood Data, care must be taken in making determinations. Users must determine if a subject property or structure falls near the boundary of an area designated as being within the CBRS and then consult the FIRM to determine the exact location of the subject property or structure relative to the CBRS boundary. In addition to these limitations, users should also be aware that the CBRS is comprised of many individual units, often contiguous to each other but carrying different Federal funding and Federal flood insurance prohibitions. Q3 Flood Data files only include the external boundaries of the CBRS as a whole. Boundaries between CBRS units of differing classifications and prohibition dates were not added to the Q3 Flood Data files. In addition, the Q3 Flood Data files do not indicate the specific classification of CBRS areas nor do they specify the prohibition dates unique to each individual area. The FIRM is the only reliable source to determine the exact Federal funding and Federal flood insurance prohibition dates for a given property or structure. Part 5 Q3 FLOOD DATA DISTRIBUTION This section discusses distribution issues including available file formats, conversion to other GIS formats, map projections for the various formats, file naming conventions, ordering instructions, organization of the Q3 Flood Data, user support, the Q3 Flood Data counties, and FEMA's revision/update plans for the Q3 Flood Data. Available Formats Q3 Flood Data products are provided in a public domain data transfer format (DLG) as well as proprietary formats (ARC/INFO and MapInfo). Although the Federal government supports several digital geospatial data models, the USGS DLG standard offers one of the more efficient and widely recognized data formats for the distribution of vector data. DLG-3 supports basic topology (spatial relationships between data elements) in a vector data model, but is limited in the area of feature annotation, non-numeric data elements, and named features. FEMA is in the process of developing specifications for data sets in SDTS, and when this effort is complete, it is expected that SDTS will replace DLG as FEMA's distributed public domain vector format. ARC/INFO and MapInfo files are used by FEMA as internal working files; however, due to the popularity and utility of these two formats, they are distributed as well. Figure 3 provides a comparison of the three vector file formats in which the Q3 Flood Data are available. File Format Comparison DLG ARC/INFO MapInfo # Attributes 28 21 21 Projection/coordinate system UTM/meters Geographic/decimal degrees Geographic/decimal degrees Horizontal datum NAD27 NAD27 NAD27 Maximum # Points/polygon 4000 4000 4000 Precision Single Double Single Format Digital Line Graph ARC/INFO export file MapInfo native tables Figure 3 Conversion to Other GIS Formats The Q3 Flood Data files are distributed by FEMA in three formats: DLG, ARC/INFO, and MapInfo. These formats may be accessed directly by the following GIS software packages:  ARC/INFO  ArcView  ArcCAD  MapInfo  GENAMAP Some GIS software packages, such as MicroStation, provide utilities to convert DLG files into their own proprietary format. The MicroStation MGE GIS Translator module provides a utility for converting DLG files to MicroStation format (design files). Other CADD and GIS software packages, such as AutoCAD, may require the Q3 Flood Data to be translated using a third party utility. Projections FEMA utilizes the UTM projection and coordinate systems for its DLG vector data (both Q3-DLGs and DFIRM-DLGs). The geographic projection and coordinate system are used for the production of Q3 Flood Data in ARC/INFO and MapInfo formats. The Q3 Raster FIRMs are not georeferenced. File Naming In order to provide for efficient file retrieval and indexing, a standardized naming convention for Q3 Flood Data was established. The following convention is DOS compatible and allows for the unique identification of any county area of digital FIRM data. All file names are in lower case letters. The vector file names are: cssccc where: c = the character 'c' ss = State FIPS code (numeric code) ccc = County FIPS code (numeric code) and: an extension specific to the file format follows. One metadata file will accompany each county file. The metadata files will be named using the same naming convention as the other files, with the exception of the letter "m" at the end (e.g., c06048.dlm, c06048m, c06048.tfm). Ordering Instructions The Q3 Flood Data are distributed on CD-ROM and will be distributed through FEMA's Internet server as the files become available. Internet users may download sample data along with associated data standards and metadata files by accessing FEMA's Map Service Center through FEMA's World Wide Web site. FEMA's address is http://www.fema.gov. Approximate download times based on file sizes will be included at this site. FEMA's Community Status Book is also available to Internet users through FEMA's Web site. CD-ROMs containing the Q3 Flood Data files may be ordered from FEMA's Map Service Center at the following address: Map Service Center P.O. Box 1038 Jessup, Maryland 20794-1038 Telephone: 1-800-358-9616 FEMA's Community Status Book and hardcopy map products are also available from FEMA's Map Service Center at the above address. Requests for maps and map products should include the full name of the community or county and the FIRM panel number(s) covered by the request. The following table (Figure 4) presents the available formats of the Q3 Flood Data products and their sources. Q3 Flood Data Product Formats Vector Q3 Flood Data DFIRM-DLG Paper FIRM LOMC Internet û (Future) û (Future) CD-ROM û û (Future) Hardcopy û û Figure 4 Data Organization Q3 Flood Data are grouped by logical geographic areas by state for distribution on CD-ROM. An indexing scheme has been developed for each state, and the indexing scheme will be available on the Internet. Each CD-ROM contains all three file formats of each dataset and associated metadata. Small states may be grouped together on one CD-ROM. Large states will be split onto several CD-ROMs. In addition, an edition numbering scheme (month/year) has been developed in order to track the currency of the Q3 Flood Data CD-ROMs. The data documentation, including this document and the Q3 Flood Data Users Guide (Reference 5), will also be distributed. User Support User support for the Q3 Flood Data products is available through FEMA's Map Service Center's toll-free number at 1-800-358-9616. Any questions about the data or problems found with the data can be directed to that number. Any problems that require FEMA's attention will be channeled back to FEMA for resolution. Q3 Flood Data Counties Approximately 880 counties were chosen for the initial phase of Q3 Flood Data production to provide maximum digital FIRM coverage in areas having high population density or growth, significant risk (from hurricanes or other flood events), or a history of repetitive losses. These counties were published on CD-ROM in 1996. Approximately 380 additional counties have been produced since 1996 and are scheduled for release in the summer of 1998. A listing of the counties targeted for Q3 Flood Data production is provided in the Q3 Flood Data Users Guide and FEMA's World Wide Web pages. Future data updates will be released in increments as the data are completed. Each release will include all FEMA supported formats of the same geographic area (i.e. DLG, ARC/INFO, and MapInfo files for the same counties). All metadata for these files will be posted on the Internet as the data are released. Revisions/Updates Revisions to Q3 Flood Data sets will begin after all initial data capture is completed. The maintenance phase of Q3 Flood Data production provides for a review of all Q3 counties on the six month anniversary of their initial data capture to determine their update needs. One exception to this procedure is when an effective DFIRM is issued prior to the six month anniversary date. When DFIRMs become effective, Q3 Flood Data will be generated from the DFIRM files as part of the DFIRM issuance procedures. Part 6 FEMA'S USES OF Q3 FLOOD DATA This section describes FEMA's in-house uses of the Q3 Flood Data within the context of the Special Flood Hazard Area (SFHA) Data Library. The objectives, data themes, deliverables, GIS environment, Q3 Flood Data tiling structure, storage requirements, and directory structure of the SFHA Data Library are presented. Objective FEMA has established a GIS environment that includes the SFHA data as one of its major components. The objective of the FEMA SFHA Data Library is to establish a library of digital geospatial data that will serve the needs of FEMA for both Response and Recovery activities and NFIP flood insurance policy marketing activities. The design of the library is intended to meet three primary requirements. 1. It must allow rapid access to and distribution of SFHA data in a variety of formats to meet specific end-user requirements. 2. It must allow utilization of existing FIRM-DLG and DFIRM-DLG data in addition to newly created Q3 Flood Data sets. The library's data design must accommodate the use, retrieval, and update of significant data from these data sets, including data sets that contain more features than the Q3 Flood Data files. 3. It must accommodate a wide variety of applications, both current and future, and allow for easy maintenance, retrieval, and query of the available data. SFHA Data Library Themes FEMA's SFHA Data Library is currently designed to maintain the Q3 Flood Data in addition to other thematic data needed for GIS applications and analysis. Selected themes are described below. SFHA Data Library Thematic Layers Theme Name Feature Type Vector Flood Insurance Rate Maps (ARC/INFO) Q3 Flood Data Vector Polygons Vector Flood Insurance Rate Maps (MapInfo) Q3 Flood Data Vector Polygons National Inventory of Structures Vector Points Street and Address Data Vector Lines Figure 5 Vector Q3 Flood Data The vector Q3 Flood Data files are currently the most important component of the FEMA SFHA Data Library. The vector Q3 Flood Data files are maintained in FEMA's SFHA Data Library as ARC/INFO polygon coverages and MapInfo native table files. Both file formats are tiled by U.S. Bureau of the Census county equivalent units, and both are delivered and maintained in decimal degrees (geographic coordinates) horizontally referenced to the North American Datum of 1927 (NAD27). The same data are distributed to the public. National Inventory of Structures Many of FEMA's GIS services involve the need to determine if a structure is in or out of the SFHA. Thus, the outline of the SFHA is one of the most critical components of the SFHA Data Library. The location of the structure may be estimated in one of several ways. FEMA's proposed National Inventory of Structures will contain highly accurate structures locations for individual addresses. Until this proposed inventory is implemented, structure information is expected to be derived from somewhat less accurate sources, including U.S. Census Bureau TIGER Line files. The structure data will take the form of geographic point locations with associated relational attributes, including the address, that allow linkage to ownership and flood insurance policy information. Deliverables Deliverables to FEMA's SFHA Data Library of Q3 Flood Data items will be on magnetic medium, in UNIX format, archived using the tape archive format (tar). The files will be contained in directories and named using the directory and naming convention outlined later in this section. (See Figure 7). FEMA's GIS Environment FEMA's GIS environment includes many different hardware and software tools. The mixed environment includes both UNIX and DOS/Windows based hardware running MapInfo, ARC/INFO, and Emergency Information System (EIS) software. In addition, many custom applications have been developed that utilize the SFHA data. The Environmental Systems Research Institute, Inc. (ESRI) ARC/INFO data format for UNIX workstations has been chosen for the FEMA SFHA Data Library because it offers the greatest flexibility and utility for development, applications, and management of digital geospatial SFHA data. Conversion from the ARC/INFO data format to the MapInfo format is provided by the MapInfo program ArcLink. EIS has adopted the ESRI ArcView2 desktop mapping software as its platform for map display and query. The GIS services currently required of the FEMA SFHA Data Library include activities that are commonly reported by U.S. Bureau of the Census county equivalent units. Thus, the county equivalent unit is used as the tiling structure for data in the FEMA SFHA Data Library. This allows for a way to filter queries and store the data using a "Librarian" concept. This librarian concept is currently based on the ARC/INFO LIBRARIAN utility. The structure, purpose, and capabilities of the ARC/INFO LIBRARIAN utility are fully documented and illustrated in the ARC/INFO User's Guide, Using Map Libraries: Spatial Management and Librarian Command References (Reference 6). Q3 Flood Data Tiling Structure In some cases, the county boundaries shown on the FIRM maps will not correspond to the county equivalent boundaries in the U.S. Census Bureau TIGER Line files. Where this is the case, an ARC/INFO coverage containing the revised county boundary (based on the FIRM county boundary) will be submitted with the Q3 Flood Data allowing insertion in the county boundary tiling and indexing file. This will eliminate gaps in FIRM coverage that could be created if the tiling boundary did not correspond to the coverage boundary. If included, the naming convention for this file will be consistent with the other file names for the county, with the extension of the letter "b" added (e.g. c06048b). Data Storage Requirements Estimates of the data storage requirements for nationwide coverage is presented in Figure 6. SFHA Data Library Storage Estimates Theme Space Format Flood Insurance Rate Maps 5 GB ARC/INFO Polygon Coverages Figure 6 Based on these estimates, complete on-line storage of the vector Q3 Flood Data layers is reasonable using magnetic disk technology. Associated vector base mapping datasets used in the GIS applications of the SFHA data may consume an additional 50 GB of storage space. SFHA Library Directory Structure As stated above, the county boundary is used as the tiling structure for Q3 Flood Data and base mapping data layers in the FEMA SFHA Data Library. This allows for a way to filter queries and store the data using the Librarian concept. Data sets are entered into the FEMA SFHA Data Library as county equivalent units. The county tiling structure defines the spatial organization of the data and allows the data to be indexed much like the index of an atlas. Each tile in the SFHA Library is defined as a directory, named using the State and County FIPS codes as follows: cssccc where: c = the character "c" ss = the two-digit State FIPS code ccc = the three-digit County FIPS code Within each library tile directory (one per county), the vector Q3 Flood Data (ARC/INFO, MapInfo, and DLG files) will be stored. Each file will be followed by an extension that indicates its file type (e.g., c06048.dlg). These files will also be named using the State and County FIPS code naming convention discussed above (e.g., c06048). A suffix of '-a', '-b', ...'-z' may be used for counties delineated by more than one non-contiguous area. The metadata files will be named using the same naming convention as the files, with the addition of the letter "m" at the end (e.g., c06048m). See Figure 7, FEMA SFHA Data Library Diagram. FEMA SFHA Data Library Diagram Figure 7 Part 7 VECTOR Q3 FLOOD DATA SPECIFICATIONS This section presents information that is common to the three vector file formats of Q3 Flood Data: the vector file definition, data capture methods, horizontal control, tiling, data sources, and attribute information. Definition The features contained in the vector Q3 Flood Data files include the following:  1% and 0.2% annual chance floodplain areas, including Zone V areas, certain floodway areas, and zone designations;  Coastal Barrier Resources System (CBRS) areas;  political areas, including community identification number;  FIRM panel areas, including panel number and suffix;  7.5-minute quadrangle areas; and  mappable Letters of Map Change (LOMCs). The vector Q3 Flood Data files do NOT include the following:  base map data (streets, etc.);  Base Flood Elevation (BFE) lines and elevations;  cross sections and letter identifiers;  Elevation Reference Marks (ERMs) and their elevations;  floodways if not shown on the FIRM,  internal boundaries of contiguous CBRS areas; and  prohibition dates associated with individual CBRS areas. Edge-matching errors, overlaps and underlaps in coverage, and similar problems are not corrected during digitizing or scanning and vectorizing. The vector Q3 Flood Data are contained in one single countywide file, including all incorporated and unincorporated areas of a county. The feature items and attributes are defined in detail later in this document. The means for linking other associated NFIP data to these files can be derived from the attributes contained within the files. For instance, the currently effective FIRM panel from the Community Status Book or the Flood Map Information System can be compared to the FIRM panel information in the Q3 Flood Data files to determine if the Q3 Flood Data files reflect the most current mapping. Data Capture Methods Data capture methods for the vector Q3 Flood Data vary, but include one or more of the following:  scanning and heads-up (or on-screen) digitizing of the effective FIRMs;  board (or table) digitizing of the effective FIRMs; and/or  derivation from already existing digital files such as FIRM-DLGs or DFIRM-DLGs. All of the above methods have as their end result a file meeting FEMA's Q3 Flood Data Specifications. Horizontal Control The hardcopy FIRMs from which the vector Q3 Flood Data are extracted contain no horizontal control. The horizontal controlling of these data is typically performed by fitting the vectors to a georeferenced raster or vector 7.5-minute quadrangle file. The horizontal control of Q3 Flood Data vector data is consistent with that required for mapping at the scale of 1:24,000. Tiling The vector Q3 Flood Data files are tiled by U.S. Bureau of the Census county equivalent units. The county boundaries shown on the FIRM maps will, in some cases, not correspond to the county equivalent boundaries in the U.S. Census Bureau TIGER Line files. Where this is the case, the FIRM county boundary is used as the bounding and tiling extents of the Q3 Flood Data files. Data Sources Q3 Flood Data are developed by scanning the existing hardcopy FIRM and vectorizing a thematic overlay of flood risks. Vector Q3 Flood Data files contain only certain features from the existing hardcopy FIRM. Sources that reflect updates effected by Letters of Map Change (Letter of Map Revision, Letter of Map Amendment) are utilized in the preparation of vector Q3 Flood Data files. These revisions are included in the vector Q3 Flood Data if they are mappable at the published scale of the FIRM. The vector Q3 Flood Data files may have been derived from DFIRM-DLGs, from FIRM-DLGs, or from FIRMs digitized previously for emergency applications, or they may be newly created files. Q3 Flood Data derived from previously created files may not contain certain items or may contain items that have been captured differently from the current vector Q3 Flood Data specifications. Items that may not be included in selected vector Q3 Flood Data files include the following:  floodways  CBRS boundaries  gutters (or zone breaks) The attribute code "IN" is used in Q3 Flood Data files for generic SFHA areas where no gutters differentiate between SFHAs of different types.  0.2% annual chance floodplains The attribute code "OUT" is used in Q3 Flood Data files for generic Zone X areas where no 0.2% annual chance floodplain boundary was captured.  FIRM panel neatlines for unprinted panels If these features are not present, the area(s) covered by these undifferentiated unprinted areas will be coded as community-based- or countywide-panel not printed areas, with the fields for panel number and panel suffix being coded with zeroes.  FIRM panel type attributes If these features are not present, the attribute code for panel type will not be populated. Panel numbers will still be present. In addition, the horizontal control of older data sets may have been consistent with that required for mapping at the scale of 1:100,000 instead of 1:24,000. Attribute Information The following clarifications on how attributes should be applied to unusual cases are included for informational purposes. This list should not be considered to be all-inclusive.  Q3 Flood Data files will show only Extraterritorial Jurisdictional Boundaries (ETJs) and no corporate limits, when both exist on the FIRMs, with the area inside the ETJs coded as within the community.  Multi-county communities will be shown in their respective counties (i.e. split by the county boundary) where both counties are in the same digital format (i.e. both Q3). If the adjacent county has not yet been digitized, the community will be shown in its entirety, with the area belonging to the adjacent county "hooked onto" the digitized county. The "hook-on" area will be coded with its appropriate county attribute codes. When the adjacent county is converted to Q3 Flood Data format, the "hook-on" area will be added to its rightful county.  "Pseudo-countywide" map panels will be coded as community based panels. Each community area will be coded individually with its appropriate county and community identification numbers.  The community based panel codes should be used when converting community based panels to Q3 Flood Data format. The countywide code should be used when coding panels shown as DFIRMs or when countywide FIRM panels are converted to Q3 Flood Data files.  For areas of communities or counties covered by panels not printed, the preferred sources of political boundaries (by order of preference) are as follows: 1. adjacent FIRM 2. FIRM index panel 3. TIGER files  For Q3 Flood Data files that are referenced to the Universal Transverse Mercator (UTM) projection and coordinate system, only one UTM zone will be used for a county. This must be reflected consistently in both the metadata and the coordinate values of the features in the files. The westernmost UTM zone for the county will be used if the county falls within more than one UTM zone.  Placeholding zeroes will be used in Q3 Flood Data files for any item for which a value is not available or appropriate.  The bounding coordinates shown in the metadata files for all vector Q3 Flood Data files will be the outside corners of the 7.5-minute quadrangle sheets that form an even rectangle around the county. If the 7.5-minute quadrangle corners fall in open bodies of water, are mapped on adjacent quads, etc., the corners of the quad will be generated based on the theoretical extent of the 7.5-minute quadrangle area (i.e., the quad outline will be completed and the corners of the completed quad will be used).  A given area should be covered by only one FIRM panel. In situations where multiple FISs are being mapped in digital format, the FIRM panel neatline code may identify a line that defines the perimeter of the intersection of the FIRM panel with the political boundary. The Q3 Flood Data file would thus potentially show the corporate boundary of a community as the FIRM panel neatline.  All FIRM panel neatlines and 7.5-minute quadrangle neatlines will stop at the county boundary for the studied county. If the county boundary is not available from the FIRM panel source maps, the U.S. Census Bureau county equivalent area outline shall be used.  In areas where FIS data overlaps, a determination should be made as to which FIS is most accurate. Typically, it is the more detailed study, or the most recent. The panel code entered in the area of overlap should correspond to the panel number of the study that was used to determine the flood hazard zone.  Floodway, Flowage Easement, and State Encroachment Areas are included in the Q3 Flood Data files if they are portrayed on the source graphic (the FIRM) used for data capture. If they are portrayed on a separate map panel (the Flood Boundary Floodway Map), they will not be digitized at this time.  Independent cities that have their own county equivalent FIPS codes will be treated the same way as counties. They will be stored and delivered in separate files named by their county equivalent FIPS codes. Part 8 Q3 FLOOD DATA ARC/INFO COVERAGE SPECIFICATIONS This section presents the specifications for the vector Q3 Flood Data in ARC/INFO format but discusses only items that differ between vector file formats. (Items common to all vector formats are discussed in Part 7, the Vector Q3 Flood Data Specifications.) These items are the projection, coordinate system, tolerances, precision, file naming, and attribute definition of the Q3 Flood Data ARC/INFO coverages. Projection/Coordinate System The Q3 Flood Data ARC/INFO coverages are created and distributed using decimal degrees in geographic coordinates, horizontally referenced to the North American Datum of 1927 (NAD27). Tolerances/Precision The Q3 Flood Data ARC/INFO coverages are delivered and maintained in double precision format. Polygon definition is limited to no more that 4000 points per polygon. Polygons of greater size (except the universal polygon) are split into smaller areas. The tolerances for data in this format in decimal degrees are as follows, with their approximate distance in meters noted: Dangle Length = 0.000000 = 0.0m Fuzzy Tolerance = 0.000009 = 1.0m Weedtolerance = 0.000009 = 1.0m Graintolerance = 0.000018 = 2.0m Editdistance = 0.000137 = 15.0m Nodesnap = 0.000018 = 2.0m Arcsnap = 0.000009 = 1.0m File Naming Each Q3 Flood Data file in ARC/INFO format is named using the State and County FIPS codes as follows: cssccc where: c = the character "c" ss = the two-digit State FIPS code ccc = the three-digit County FIPS code Each file is followed by an extension that indicates its type. ARC/INFO export files are followed by the extension .e00 (e.g., c06048.e00). The Q3 Flood Data ARC/INFO coverage metadata files are named using the same naming convention as the coverages, with the addition of the letter "m" at the end (e.g., c06048m). One metadata file will accompany each countywide Q3 Flood Data ARC/INFO coverage. arcÄÄÄÄÄÂÄ c06048.e00 ÀÄ c06048m Attribute Definition All polygon features in the Q3 Flood Data ARC/INFO coverages are described by a series of attributes that provide information about their flood hazard zone, community number, FIRM panel number, and USGS 7.5-minute quadrangle number. The following tables (Figures 8 - 14) define these attributes. Please note that the items AREA and PERIMETER are system-defined items, and their width is based on the precision, units, and geographic location of the coverage. Their width may vary, and all subsequent item positions may also vary. Q3 Flood Data ARC/INFO Coverage Attribute Definition Q3.PAT DEFINITION POS ITEM NAME W W T D DESCRIPTION 1 AREA 8 12 F 6 Polygon area 9 PERIMETER 8 12 F 6 Polygon perimeter 17 Q3# 4 5 B 0 Record number 21 Q3-ID 4 5 B 0 Polygon ID 25 FIPS 5 5 C - State and County FIPS codes 30 COMMUNITY 4 4 C - FEMA Community ID number 34 FIRM_PANEL 11 11 C - FIRM panel number 45 QUAD 8 8 C - USGS quadrangle identifier (Key to RQUAD files) 53 ZONE 5 5 C - Flood hazard zone (See Table 4) 58 FLOODWAY 5 5 C - Floodway type (See Table 5) 63 COBRA 9 9 C - COBRA identifier (See Table 6) 72 SFHA 3 3 C - In/Out determination 76 SYMBOL 4 5 B - Polygon shade symbol (See Tables 4 and 8) 79 PANEL_TYP 4 4 C - Type of FIRM panel (See Table 7) REDEFINED ITEMS 25 ST-FIPS 2 2 C - State FIPS code 27 CO-FIPS 3 3 C - County FIPS code 34 STATE 2 2 C - State FIPS code 36 PCOMM 4 4 C - FIRM community/county identifier 40 PANEL 5 5 C - FIRM panel number and suffix (Key to RFIRM files) 45 LAT 2 2 C - Origin latitude of 7.5-minute quad 47 LONG 3 3 C - Origin longitude of 7.5-minute quad 51 QUAD_UNIT 2 2 C - Index number to 7.5-minute quad Figure 8 FIPS This item contains the five-digit State and County FIPS code, as defined in the Federal Information Processing Standard Publication 6-4 (FIPS PUB 6-4) (Reference 7), published by the National Institute of Standards and Technology. The State and County FIPS codes are further separated by the redefined items ST-FIPS and CO-FIPS. COMMUNITY This item contains the four-digit community identification number assigned by FEMA to each community that participates in the NFIP. This number may be found in the title block of each FIRM panel, or in the NFIP Community Status Book. FIRM_PANEL This item contains the eleven-digit FIRM panel number. The FIRM panel number is found in the title block of each FIRM panel. The FIRM panel number is further separated into its components by the redefined items STATE (contains the State FIPS code), PCOMM (for countywide panels, this is the County FIPS code plus the letter "c"; for community based panels, this is the community identification number), and PANEL (the panel number and suffix). QUAD This item contains the eight-digit USGS quadrangle identification number. It identifies the alphanumeric map sheet identifier used by the USGS. The list of values for each state is published by USGS in the State Indexes to Topographic and Other Map Coverage (Reference 8). This item is further separated into its components by three redefined items. They are LAT (the latitude, rounded down to the nearest whole degree, of the 7.5-minute quadrangle map sheet), LONG (the longitude, rounded down to the nearest whole degree, of the 7.5-minute quadrangle map sheet), and QUAD_UNIT (the alphanumeric map sheet identifier used by USGS, A1 through H8). ZONE This item contains a representation of the flood hazard zone designator. The flood hazard zones are defined in Figure 9, Q3 Flood Data ARC/INFO Coverage SFHA Zone Definition. FLOODWAY This item contains a representation of the floodway type. The floodway types are defined in Figure 10, Q3 Flood Data ARC/INFO Coverage Floodway Area Definition. Floodway, Flowage Easement, and State Encroachment Areas are included in the Q3 Flood Data files if they are portrayed on the source graphic (the FIRM) used for data capture. If they are portrayed on a separate map panel (the Flood Boundary Floodway Map), they will not be included in the Q3 Flood Data files. COBRA This item indicates whether the area is inside or outside of a designated Coastal Barrier Resources System area. Only the extents of the Coastal Barrier Resources System area boundaries are portrayed in the Q3 Flood Data files. The boundaries between Coastal Barrier Resources System areas with different designation dates are not included in the Q3 Flood Data files. Users should refer to the FIRM for such information. The COBRA types are defined in Figure 11, Q3 Flood Data ARC/INFO Coverage Coastal Barrier Area Definition. SFHA This item indicates whether the area is in or out of the SFHA. It is derived from the area's flood hazard zone designation. The SFHA definitions that correspond with each of the flood hazard zone types are shown in Figure 9. Please note that areas whose ZONE is listed as Area Not Included (ANI) are given the SFHA attribute of "OUT," even though their SFHA designation is unknown at this time. SYMBOL This item represents a polygon shade symbol that is unique to the Zone, Floodway, and COBRA area definitions. See Figure 13. Users should note that in order to replicate these colors, a Q3 Flood Data Shadeset must be installed. PANEL_TYP This item contains a representation of the FIRM panel type. See Figure 12, Q3 Flood Data ARC/INFO Coverage FIRM Panel Type Definition. Figure 9: Q3 Flood Data ARC/INFO Coverage SFHA Zone Definition Zone Name ZONE SFHA SYMBOL Description Zone V V In 1 An area inundated by 1% annual chance flooding with velocity hazard (wave action); no BFEs have been determined. Zone VE VE In 2 An area inundated by 1% annual chance flooding with velocity hazard (wave action); BFEs have been determined. Zone A A In 3 An area inundated by 1% annual chance flooding, for which no BFEs have been determined. Zone AE AE In 4 An area inundated by 1% annual chance flooding, for which BFEs have been determined. Zone AO AO In 5 An area inundated by 1% annual chance flooding (usually sheet flow on sloping terrain), for which average depths have been determined; flood depths range from 1 to 3 feet. Zone AO (Alluvial Fan) AOVEL In 6 An alluvial fan inundated by 1% annual chance flooding (usually sheet flow on sloping terrain), for which average flood depths and velocities have been determined; flood depths range from 1 to 3 feet. Zone AH AH In 7 An area inundated by 1% annual chance flooding (usually an area of ponding), for which BFEs have been determined; flood depths range from 1 to 3 feet. Zone A99 A99 In 8 An area inundated by 1% annual chance flooding, for which no BFEs have been determined. This is an area to be protected from the 1% annual chance flood by a Federal flood protection system under construction. Zone D D Out 9 An area of undetermined but possible flood hazards. Zone AR (Future) AR In 10 An area inundated by flooding, for which BFEs or average depths have been determined. This is an area that was previously, and will again, be protected from the 1% annual chance flood by a Federal flood protection system whose restoration is Federally funded and underway. Zone X (0.2% Annual Chance) X500 Out 11 An area inundated by 0.2% annual chance flooding; an area inundated by 1% annual chance flooding with average depths of less than 1 foot or with drainage areas less than 1 square mile; or an area protected by levees from 1% annual chance flooding. Zone X X Out 12 An area that is determined to be outside the 1% and 0.2% annual chance floodplains. 1% Annual Chance Flood Discharge Contained in Channel 100IC In 13 An area where the 1% annual chance flooding is contained within the channel banks and the channel is too narrow to show to scale. An arbitrary channel width of 3 meters is shown. BFEs are not shown in this area, although they may be reflected on the corresponding profile. 0.2% Annual Chance Flood Discharge Contained in Channel 500IC Out 14 An area where the 0.2% annual chance flooding is contained within the channel banks and the channel is too narrow to show to scale. An arbitrary channel width of 3 meters is shown. Floodway Contained in Channel FWIC In 15 An area where the floodway is contained within the channel banks and the channel is too narrow to show to scale. An arbitrary channel width of 3 meters is shown. BFEs are not shown in this area, although they may be reflected on the corresponding profile. Flood Prone Area FPQ In 16 An area designated as a "Flood Prone Area" on a map prepared by USGS and the Federal Insurance Administration. This area has been delineated based on available information on past floods. This is an area inundated by 1% annual chance flooding for which no BFEs have been determined. Area in SFHA IN In 17 An area designated as within a "Special Flood Hazard Area" (or SFHA) on a FIRM. This is an area inundated by 1% annual chance flooding for which BFEs or velocity may have been determined. No distinctions are made between the different flood hazard zones that may be included within the SFHA. These may include Zones A, AE, AO, AH, A99, AR, V, or VE. Area Outside SFHA OUT Out 18 An area designated as outside a "Special Flood Hazard Area"(or SFHA) on a FIRM. This is an area inundated by 0.2% annual chance flooding; an area inundated by 1% annual chance flooding with average depths of less than 1 foot or with drainage areas less than 1 square mile; an area protected by levees from 1% annual chance flooding; or an area that is determined to be outside the 1% and 0.2% annual chance floodplains. No distinctions are made between these different conditions. These may include both shaded and unshaded areas of Zone X. Area Not Included ANI Out 0 An area that is located within a community or county that is not mapped on any published FIRM. Area of Undesignated Flood Hazard UNDES Out 0 A body of open water, such as a pond, lake, ocean, etc., located within a community's jurisdictional limits, that has no defined flood hazard. Figure 9 Q3 Flood Data ARC/INFO Coverage Floodway Area Definition Floodway Type FLOODWAY Symbol Description Floodway FW See Figure 13 An area that includes the channel of a river or other watercourse and the adjacent land areas that must be reserved in order to discharge the base flood without cumulatively increasing the water-surface elevation by more than a designated height. (Note: this area is normally in Zone AE.) Flowage Easement Area EASE See Figure 13 An area within a community, usually bordering a stream, that has more restrictive floodplain development criteria imposed upon it by the governing body (town, city, etc.) than the criteria imposed as a prerequisite to participation in the NFIP. (Note: Unlike the floodway, this area may overlap any other flood zone.) State Encroachment Area STATE See Figure 13 An area within a community, usually bordering a stream, that has more restrictive floodplain development criteria imposed upon it by the state, than the criteria imposed as a prerequisite to participation in the NFIP. (Note: Unlike the floodway, this area may overlap any other flood zone.) Figure 10 Q3 Flood Data ARC/INFO Coverage Coastal Barrier Resources System Area Definition COBRA Type COBRA Symbol Description Inside Coastal Barrier Resources System area COBRA_IN See Figure 13 An area designated as within the Coastal Barrier Resources System in which flood insurance is unavailable for structures newly built or substantially improved after the Coastal Barrier date. The specific Coastal Barrier designation date is available on the printed FIRM. Outside Coastal Barrier Resources System area COBRA_OUT See Figure 13 An area outside the Coastal Barrier Resources System. Figure 11 Q3 Flood Data ARC/INFO Coverage FIRM Panel Type Definition FIRM Panel Type PANEL_TYP Description Community based - panel printed CBPP The portion of a community covered by a community based map sheet (panel). A community may consist of more than one FIRM panel. The FIRM panel is further identified by its FIRM panel number and its suffix. Community based - panel not printed CBNP The portion of a community covered by a community based map sheet (panel) that is not printed. The FIRM panel is further identified by its FIRM panel number and its suffix. Countywide - panel printed CWPP The portion of a community covered by a countywide map sheet (panel). A community may consist of more than one FIRM panel. The FIRM panel is further identified by its FIRM panel number and its suffix. Countywide - panel not printed CWNP The portion of a community covered by a countywide map sheet (panel) that is not printed. The FIRM panel is further identified by its FIRM panel number and its suffix. Area outside FIRM panel neatline AOPN Any unpanelled areas of a participating county. It should be used to identify any areas that fall within a participating community but outside of the defined panelling scheme. It should not be confused with the Unmapped Community attribute, which should be used for unmapped or non-participating communities. Unmapped community UNMC A jurisdiction that has not been mapped or identified by the National Flood Insurance Program (NFIP). It may be applied to a jurisdiction that has no maps because it has no Special Flood Hazard Area, or it may be applied to a jurisdiction that is not identified by the NFIP or is not participating in the NFIP. Figure 12 Q3 Flood Data ARC/INFO Coverage Polygon Shades Q3 Flood Data ARC/INFO Coverage Attribute Combinations FIPS COMM-ID PANEL# QUAD# ZONE FLOODWAY COBRA SFHA SYMBOL PANEL_TYP 5-Digit FIPS Code 4-Digit CID 11-Digit FIRM Panel # 7-Digit USGS Quad # V Blank COBRA_IN COBRA_OUT In 1 CBPP CBNP CWPP CWNP AOPN VE In 2 A In 3 AE FW EASE STATE Blank In 4 AO In 5 AOVEL In 6 AH In 7 A99 In 8 D Blank Out 9 AR (Future) EASE STATE Blank In 10 X500 EASE STATE Blank Out 11 X Out 12 CBPP CBNP CWPP CWNP UNMC 100IC FW EASE STATE Blank In 13 CBPP CBNP CWPP CWNP AOPN 500IC EASE STATE Blank Out 14 FWIC FW In 15 FPQ Blank In 16 IN FW Blank In 17 OUT Blank Out 18 0000 00000000000 ANI COBRA_OUT Out* 0 CWPP CWNP UNMC AOPN 4-Digit CID 11-Digit FIRM Panel # UNDES COBRA_IN COBRA_OUT Out 0 CWPP CWNP CBPP CBNP AOPN Figure 14 Part 9 Q3 FLOOD DATA MAPINFO FILE SPECIFICATIONS This section presents the specifications for the vector Q3 Flood Data in MapInfo format but discusses only items that differ between vector file formats. (Items common to all vector formats are discussed in Part 7, the Vector Q3 Flood Data Specifications.) These items are the projection, coordinate system, tolerances, precision, file naming, and attribute definition of the Q3 Flood Data MapInfo files. Q3 Flood Data in the MapInfo Information Systems Corporation format was included in the FEMA SFHA Data Library because the MapInfo Desktop mapping software (both UNIX and PC-Windows versions) is currently used by FEMA for hazard identification, risk assessment, and disaster response and recovery efforts. During disaster events, the Q3 Flood Data have proven to be a valuable tool for estimating the potential for loss and are used in the development of briefing maps in support of Emergency Support Function 5 (ESF-5) of the Federal Response Plan. Projection/Coordinate System The Q3 Flood Data MapInfo files are created and distributed using decimal degrees in geographic coordinates, horizontally referenced to the North American Datum of 1927 (NAD27). Tolerances/Precision The Q3 Flood Data MapInfo files are delivered and maintained in single precision format. Polygon definition is limited to no more that 4000 points per polygon. Polygons of greater size (except the universe polygon) are split into smaller areas. The tolerances for data in this format in decimal degrees are as follows, with their approximate distance in meters noted: Dangle Length = 0.000000 = 0.0m Fuzzy Tolerance = 0.000009 = 1.0m Weedtolerance = 0.000009 = 1.0m Graintolerance = 0.000018 = 2.0m Editdistance = 0.000137 = 15.0m Nodesnap = 0.000018 = 2.0m Arcsnap = 0.000009 = 1.0m File Naming Each Q3 Flood Data file in MapInfo format is named using the State and County FIPS codes as follows: cssccc where: c = the character "c" ss = the two-digit State FIPS code ccc = the three-digit County FIPS code Each file is followed by an extension that indicates its type. MapInfo files are followed by the extensions .tab, .dat, .map, and .id (e.g., c06048.tab). The Q3 Flood Data MapInfo metadata files are named using the same naming convention as the coverages, with the addition of the extension .mim at the end (e.g., c06048.mim). One metadata file will accompany each set of countywide Q3 Flood Data MapInfo files. mapÄÄÄÂÄ c06048p.tab ÃÄ c06048p.dat ÃÄ c06048p.map ÃÄ c06048p.id ÀÄ c06048.mim Attribute Definition MapInfo format files are produced by direct translation of the Q3 Flood Data ARC/INFO coverages using the MapInfo ArcLink program. All data from the original ARC/INFO coverage is exported and converted. All attributes and attribute names are equivalent in the MapInfo version of the Q3 Flood Data and the corresponding tables describing this information (Figures 8-14) for the Q3 Flood Data ARC/INFO coverages may be used for reference. The ArcLink translator adds one logical item to the attribute list described in Figure 8. It is named SPLIT. SPLIT is used as a flag to indicate that a polygon from the original Q3 Flood Data ARC/INFO coverage has been bisected in translation. There are differences in terminology for ARC/INFO and MapInfo files. ARC/INFO features are translated into MapInfo features according to Figure 15. ARC/INFO to MapInfo Feature Translation ARC/INFO MapInfo points, nodes, tics points arcs lines or polylines polygons regions annotation text data data with no graphic objects Figure 15 All information pertinent to the data definition of the MapInfo format files is described in Part 8, Q3 Flood Data ARC/INFO Coverage Specifications. Part 10 Q3 FLOOD DATA DLG SPECIFICATIONS This section presents the specifications for the vector Q3 Flood Data in Digital Line Graph (DLG) format but discusses only items that differ between vector file formats. (Items common to all vector formats are discussed in Part 7, the Vector Q3 Flood Data Specifications.) These items are the projection, coordinate system, tolerances, precision, file naming, DLG structure, file header information, data record information, and attribute definition of the Q3 Flood Data DLG files. Projection/Coordinate System The Q3 Flood Data in DLG format (Q3-DLGs) are distributed using the Universal Transverse Mercator (UTM) projection and coordinates, horizontally referenced to NAD27. If a county falls within more than one UTM zone, the zone to the west will be used for the entire county. Some user applications may be facilitated by converting the Q3-DLG files to other coordinate systems. UTM data may be easily reprojected using a public domain software module such as USGS' General Cartographic Transformation Package (GCTP). The use of UTM is intended to facilitate the integration of FEMA data with other USGS data sets, such as US Geodata (DLG), Digital Orthoquads (DOQ), or Digital Raster Graphic (DRG). Tolerances/Precision Polygon definition is limited to no more that 4000 points per polygon. Polygons of greater size (except the outside area polygon) are split into smaller areas. Q3-DLGs will contain no duplicate vertices. The line record listings of the x and y coordinates of the nodes and vertices that define the linear features will contain no duplicate records. The tolerances used for the collection of the Q3-DLG data are as follows: Dangle Length = 0.0m Fuzzy Tolerance = 1.0m Weedtolerance = 1.0m Graintolerance = 2.0m Editdistance = 15.0m Nodesnap = 2.0m Arcsnap = 1.0m File Naming Each Q3-DLG is named using the State and County FIPS codes as follows: cssccc where: c = the character "c" ss = the two-digit State FIPS code ccc = the three-digit County FIPS code Each file is followed by an extension that indicates its type. DLG files are followed by the extension .dlg (e.g., c06048.dlg). The Q3-DLG metadata files are named using the same naming convention as the files, with the addition of the extension .dlm at the end (e.g., c06048.dlm). One metadata file will accompany each countywide Q3-DLG file. dlgÄÄÄÂÄ c06048.dlg ÀÄ c06048.dlm Digital Line Graph Structure The Q3-DLG file structure is designed to accommodate all categories of spatial data represented on a conventional map. Node, line, and area data types are accepted. The attribute coding scheme is designed to accommodate basic thematic data categories such as flood hazard zone features. Additional information regarding the structure of DLG files may be found in the Standards for Digital Line Graphs published by the U. S. Geological Survey (Reference 9). DLG-3 Topology Current Q3 Flood Data collection is directed toward producing fully topologically structured DLG data, referred to as DLG-3. The DLG-3 concept is based on graph theory in which a two-dimensional diagram is expressed as a directed graph composed of a set of nodes (topologically significant points), lines, and areas in a manner that explicitly expresses logical relationships. Applied to a map, this concept is used to encode the digital data with the spatial relationships between map elements that are obvious when the map is examined visually. The spatial relationships include such concepts as adjacency, proximity, and connectivity between features on the map. The abstraction of the map data according to the rules of graph theory preserves the spatial relationships inherent in the map graphic and creates a logical and consistent data file structure for computer processing. A digital file of cartographic or geographic data that maintains the spatial relationships inherent in the map is called a topologically structured data file. A topologically structured data file can support simple graphic applications, such as plotting, as well as more advanced applications, such as computations and analysis involving areas and lines and their spatial relationships. Topological Elements A DLG-3 file is composed of three separate, but related, elements: nodes, lines, and areas.  Nodes define the location of the endpoints of every line, and a single node may mark the start or end of one or more lines. Thus, nodes occur at intersections of linear features and at other places on linear features where the feature is subdivided into separate line segments.  Lines are ordered sets of points that describe the position and shape of a linear feature on the map. Each line starts at a node and ends at a node, has an area to the left of its direction of travel, and has an area to the right of its direction of travel. The direction of travel is arbitrarily determined at the time of data capture. Lines connect to each other at nodes, and a line does not cross itself or any other line. A line may describe the boundary between two areal map features, such as counties, or may define a map feature by itself, such as a stream. A special line, called a degenerate line, is used to define features symbolized as isolated (non-connecting) point features on a map. A degenerate line starts and ends at the same node, has two identical coordinate pairs, has zero length, and has the same area to the left and right of the direction of travel; that is, it is totally enclosed inside one map area. Topologically, a degenerate line is considered to be a fully connected line, since the attached node has a node-line list count of two.  Areas are continuous, unbroken regions of the map bounded by lines. Each area is identified in a DLG-3 data file by a unique area point located inside the area it represents. Also, every DLG data file will have at least two areas identified: one representing the area covered by the file and the other representing the area outside the coverage of the file. Polygons as unique features are not defined explicitly in a DLG file. However, polygons can be constructed using line-area linkages built into the DLG data structure. Attribute Codes In addition to locational and topological information, DLG data elements have explicitly encoded attributes. Attribute codes are used to describe the map information represented by a node, area, or line. For example, the attribute code for an area might identify a Zone AE. A listing of all the attribute codes currently assigned and used in Q3-DLG files is contained in this document. Each attribute code identifies the major category to which a data element belongs, as well as the specific nature of the element. Codes also may provide additional descriptive information. All Q3 Flood Data elements are described by fourteen attribute codes for a complete description. Since multiple attributes are needed to describe an element, the order is significant. A DLG attribute code is composed of two distinct numeric fields: a three-digit major code, which identifies the major category to which the element belongs, and a four-digit minor code, which specifically describes the element. In the digital file, the major and minor attributes are encoded in two integer fields of six digits, right justified with leading blanks (FORTRAN 2I6 format). In this document, major codes are presented as three digits, and minor codes are presented as four digits. Leading zeros are shown only for clarity; for example: 440 0153.  Major Attribute Codes The first two digits of the major code uniquely identify the category to which the described element belongs. The third digit of the major code is used to modify the minor code in two ways: - If zero, the minor code represents a description or classification of the element. - If non-zero, the minor code which follows is a parameter requiring special interpretation according to instructions given in the codes for each category.  Minor Attribute Codes The first digit of the minor code is normally zero. If non-zero, it is used as a modifier to provide additional information. The remaining three digits are normally used to indicate the cartographic interpretation to be applied to specific elements. The type of element described by a particular code usually can be determined from the range of value of the last three digits: 001 - 099 = nodes 100 - 199 = areas 200 - 299 = lines 300 - 399 = degenerate lines 400 - 499 = codes which may be applied to any element type (nodes, lines, areas, or points) 601 - 699 = general descriptive codes Only area codes are contained in the Q3-DLGs. The last three digits (and occasionally all four digits) also may be used as a parameter code. Parameters are used when a minor code can legitimately assume a range of values, such as a panel number. The meaning of a parameter code is indicated by the (non-zero) third digit of the major code. An example of a Major/Minor code pair is 440 0153, which indicates that an area is being described. The definition of the minor attribute codes is found in the following section. Every area within a Q3 Flood Data county is identified using fourteen Major/Minor attribute code pairs. They are arranged in the following order: 410 ---, 410 State FIPS, 411 County FIPS, 412 CID, 420 ----, 421 Panel #, 422 Suffix, 420 170, 426 Latitude, 427 Longitude, 428 Quad ID, 440 Zone, 440 Floodway, 440 COBRA. Placeholders of zero are used for any item that does not require an attribute code or parameter code. Cell Size and File Extent The Q3-DLGs are stored and distributed in county units. The file extents will be the outermost four corners of the USGS 7.5-minute quadrangle map sheets on which the county falls. "Optional" Format The Optional distribution format was designed to facilitate data usage. The topological relationships explicitly encoded include starting node, ending node, area to the left of direction of travel, and area to the right of the direction of travel for line elements, bounding lines for area elements, and bounded lines for node elements. These files can simplify processing requirements. For example, because topological linkages are explicitly encoded for all line, node, and area elements, a polygon data structure can be easily created. These linkages facilitate GIS applications of Q3-DLG data as well as generation of graphic products. The files are physically comprised of ASCII characters organized into fixed-length logical records of 80 characters (bytes). Bytes 1-72 of each record contain DLG data, and bytes 73-80 may be blank or contain a record sequence number. The record types used in the Optional DLG distribution format may be categorized as header and data records. Sequence of Records The actual sequence of records in an Optional distribution format DLG file is as follows: 1. Header records Ten file identification and description records Control point identification records (one per control point) Data category identification records (one per data category in the file) 2. Data records Node identification record Repeated Node-to-line linkage record(s) for each Attribute Code record(s) node within a data category Area identification record Repeated Area-to-line linkage record(s) for each Attribute code record(s) area within a data category Line identification record Repeated Coordinate string record(s) for each Attribute code record(s) line within a data category File Header Information The header file is physically comprised of 8-bit ASCII characters organized into a fixed length logical record of 80 characters. The header information includes the name of the digital cartographic unit, map scale, date of original source material, date of last revision, and a banner. The following further defines the aforementioned. Banner: Defines the banner, which is comprised of information unique to the Q3 Flood Data file. The banner is a string of up to 72 alphanumeric characters, with the following record format. All fields except the FIPS codes are left justified with trailing spaces. FEMA Identifier. FEMA-Q3 Record length 12 Data Category. Flood Hazard Zones Record length 20 County, State. County the Q3-DLG covers, followed by a comma and its two-character state abbreviation. Record length 30. State FIPS code. State code should be two digits with leading zero if necessary. Record length 2. County FIPS code. County code should be three digits with leading zero(s), if necessary, followed by trailing space. Record length 4. Name of Cartographic Unit: Defines the name of the county, followed by the state two-character designator. The name is a string of up to 40 alphanumeric characters. Date of Original Source, Date of Revision: Defines the year of the original digitization of the Flood Insurance Rate Map followed by a comma and the year of the latest revision date if applicable. The date may be a string of up to 10 alphanumeric characters. Revision Date Qualifier: Qualifier to discriminate revision date if present. Code is: R = Restudy, L = Limited Map Maintenance Program (LMMP), V = Revision under parts 65, 67, 70. Scale of Source Material: Defines the map scale. Usually 24000. UTM Coordinate Zone: Defines the zone in the ground planimetric reference system. Appendix E lists the UTM coordinate zone codes. Resolution: Defines the true ground distance corresponding to one unit (0.001 inch at map scale) in the file internal coordinate system used in data collection. Scale Resolution 1:24,000 0.61M 1:25,000 0.635M 1:48,000 1.22M 1:62,500 1.587M Horizontal Datum: Defines the horizontal datum of the Q3-DLG. Options are: 0 = NAD 27 1 = NAD 83 2 = Puerto Rico 3 = Old Hawaiian 4 = Local Vertical Datum: Defines the vertical datum of the Q3-DLG. Options are: 0 = NGVD 29 1 = NAVD 88 2 = Local Mean Sea Level Map Projection Parameters: The Optional DLG distribution format includes 15 fields reserved for map projection parameters. These parameters are typically used as input for a coordinate transformation package. When the ground coordinate system of a DLG is the Universal Transverse Mercator system, as in the case for all Q3-DLGs, only the first two of the 15 parameter fields are used: 1. Longitude of any point in UTM zone. Normally placed at the 2. Latitude of any point in UTM zone. center of the DLG cell. 3-15. Not used (=0). A transformation to or from UTM using a coordinate transformation package can be controlled by specifying the UTM zone or by supplying the geographic coordinate in parameters 1 and 2, from which the UTM zone is computed. FEMA Q3-DLGs require both to be present. The parameters are encoded as packed, degrees-minutes-seconds (DMS) as follows: degrees * 1000000 + minutes * 1000 + seconds Example: If degrees = +50, minutes = 30, and seconds = 36.25, then the parameter value is 50030036.25 stored as a REAL*8 variable, and "bbb0.500300362500000D 08" encoded in FORTRAN D24.15 format. Control Point Label with Latitude and Longitude and X,Y Coordinates: Defines a list of four control points, one for each corner of the map sheet with their latitude and longitude values in decimal degrees and the corresponding X,Y coordinates of each point in units of the ground planimetric coordinate system. Data Category Identification Record: Identifies the data category. Flood Hazard Zones Sample Header File An example of a Q3-DLG header file is as follows: FEMA-Q3 FLOOD HAZARD ZONES FAIRFIELD CO, CT 09001 FAIRFIELD COUNTY, CT 1992 24000 3 1 18 2 0.61000000000D+00 4 0 4 1 1 1 -0.730180450000000D+08 0.410030450000000D+08 0.000000000000000D+00 0.000000000000000D+00 0.000000000000000D+00 0.000000000000000D+00 0.000000000000000D+00 0.000000000000000D+00 0.000000000000000D+00 0.000000000000000D+00 0.000000000000000D+00 0.000000000000000D+00 0.000000000000000D+00 0.000000000000000D+00 0.000000000000000D+00 0.10000000000D+01 0.00000000000D+00 0.00000000000D+00 0.00000000000D+00 SW 41.000000 -73.375000 636671.25 4539816.86 NW 41.125000 -73.375000 636412.66 4553693.75 NE 41.125000 -73.250000 646906.37 4553897.09 SE 41.000000 -73.250000 647184.87 4540020.07 FLOOD HAZARD ZONES 0 8 8 010 6 6 010 12 12 1 Data Record Information In the Optional DLG distribution format, topological linkages are explicitly encoded for node and area elements as well as for line elements. Seven types of records are considered data records:  Node and area identification records  Node-to-line linkage records  Area-to-line linkage records  Line identification records (also contains line-to-node and line-to-area linkages)  Coordinate string records  Attribute code records  Text records (not currently used) USGS's Standards for Digital Line Graphs (Reference 9) lists the record contents for DLG files in Optional format. Refer to this listing for additional data record specifications. Attribute Definition All area features in the Q3-DLG files are described by a series of attributes that provide information about their flood hazard zone, community number, FIRM panel number, and USGS 7.5-minute quadrangle number. Figure 15, Q3-DLG Attribute Coding, defines these attributes. Figure 16 provides information on the Q3-DLG attribute code domains. The following clarifications are provided for three unique attribute definitions. Outside Area Each DLG provides a coherent description of that portion of the earth's surface covered by a county cell. To maintain topological consistency and to facilitate the combination (integration) of multiple counties, the area outside the county cell is specifically identified for each Q3-DLG. This area element, which must be the first area present in each Q3-DLG file, is assigned fourteen major and minor codes, all equal to zero. Placeholding Zeroes For all features contained in the Q3-DLG for which no attribute code has been explicitly defined, the attribute code records must be zero. Attribute codes of 0 are used as placeholders to allow for adjoining areas to be readily combined with a minimum of additional processing. Placeholding zeroes will be used for any minor code field for which a value is not available or appropriate. The appropriate major code will be retained whenever possible. Attribute Code Order Every area within the county should be identified using fourteen Major/Minor attribute code pairs. They should be arranged in the following order: 410 ---, 410 State FIPS, 411 County FIPS, 412 CID, 420 ----, 421 Panel #, 422 Suffix, 420 170, 426 Latitude, 427 Longitude, 428 Quad ID, 440 Zone, 440 Floodway, 440 COBRA. Figure 16: Q3-DLG Attribute Coding Position Major Code Minor Code Descriptor Comments OUTSIDE AREA 000 0000 Outside Area Each Q3-DLG provides a coherent description of that portion of the earth's surface covered by a county cell. To maintain topological consistency and to facilitate the combination (integration) of multiple counties, the area outside the cell is specifically identified for each Q3-DLG file. This area element, which must be the first area present, is assigned a series of fourteen attribute codes with major and minor codes all equal to zero. POLITICAL AREAS Major1/ Minor1 410 0101 Community Area This code identifies a county, city, village, town, borough, township, or hamlet, or political subdivision thereof. The community has authority to adopt and enforce floodplain management regu- lations for the areas within its jurisdiction. The community is further identified by its state FIPS code (parameter code 410 00--), its county FIPS code (parameter code 411 0---), and its community number (parameter code 412 ----). 410 0150 Undefined Political Area This code identifies an area outside the political boundaries of the studied community or county. Major2/ Minor2 410 00-- State FIPS Code Right justified; 2 digits. Major3/ Minor3 411 0--- County or County Equivalent FIPS Code Right justified; 3 digits. Major4/ Minor4 412 ---- Community Identification Number Right justified; 4 digits. Figure 16: Q3-DLG Attribute Coding Position Major Code Minor Code Descriptor Comments FEMA MAP PANEL AREAS Major5/ Minor5 420 0150 Community-based FIRM Panel This code identifies the portion of a community covered by a community-based map sheet (panel). A community may consist of more than one FIRM panel. The FIRM panel is further identified by its FIRM panel number (parameter code 421 ----) and its suffix (parameter code 422 00--). 420 0151 Area Outside FIRM Panel Neatline This code identifies any unpanelled areas of a participating county. It should be used to identify any areas that fall within a participating community but outside of the defined panelling scheme. It should not be confused with the Unmapped Community attribute, which should be used for unmapped or non-participating communities. 420 0152 Community-based Panel Not Printed This code identifies the portion of a community covered by a community-based map sheet (panel) that is not printed. The FIRM panel is further identified by its FIRM panel number (parameter code 421 ----) and its suffix (parameter code 422 00--). 420 0153 Countywide FIRM Panel This code identifies the portion of a community covered by a countywide map sheet (panel). A community may consist of more than one FIRM panel. The FIRM panel is further identified by its FIRM panel number (parameter code 421 ----) and its suffix (parameter code 422 00--). 420 0154 Countywide FIRM Panel Not Printed This code identifies the portion of a community covered by a countywide map sheet (panel) that is not printed. The FIRM panel is further identified by its FIRM panel number (parameter code 421 ----) and its suffix (parameter code 422 00--). Figure 16: Q3-DLG Attribute Coding Position Major Code Minor Code Descriptor Comments Major 5/ Minor 5 (cont'd) 420 0155 Unmapped Community This code identifies a jurisdiction that has not been mapped or identified by the National Flood Insur- ance Program (NFIP). It may be applied to a juris- diction that has no maps because it has no Special Flood Hazard Area, or it may be applied to a jurisdiction that is not identified by the NFIP or is not participating in the NFIP. Major6/ Minor6 421 ---- FIRM Panel Number Right justified; 4 digits. Major7/ Minor7 422 00-- FIRM Panel Suffix This code is used to encode the alphabetic portion of the map panel number. The code substitutes the numeric equivalent 01 to 26 for the letters A to Z. It is right justified; two digits. USGS QUADRANGLE AREAS Major8/ Minor8 420 0170 USGS Quadrangle This code identifies the portion of the county covered by a given USGS 7.5-minute quadrangle map sheet. Major9/ Minor9 426 ---- Latitude This code identifies the latitude, rounded down to the nearest whole degree, of the 7.5-minute quadrangle map sheet. A map sheet whose southeast corner coordinates were -89ø 15', 42ø 30' would be represented by the Latitude code 42. Major10/Minor10 427 ---- Longitude This code identifies the longitude, rounded down to the nearest whole degree, of the 7.5-minute quadrangle map sheet. A map sheet whose southeast corner coordinates were -89ø 15', 42ø 30' would be represented by the Longitude code 89. Major11/Minor11 428 ---- Quadrangle Identifier This code identifies the alphanumeric map sheet identifier used by the USGS. Refer to the list of USGS codes published in the State Indexes to Topographic and Other Map Coverage for a list of these values. The alphabetic portion of the identifier is translated to its numeric equivalent by substituting the numbers 1 to 8 for the letters A to H. Thus, the map sheet identifier A1 would be represented by 11, and H8 would be represented by 88. Figure 16: Q3-DLG Attribute Coding Position Major Code Minor Code Descriptor Comments FLOOD HAZARD ZONE AREAS Major12/Minor12 440 0150 Zone V This code identifies an area inundated by 1% annual chance flooding with velocity hazard (wave action); no BFEs have been determined. 440 0151 Zone VE This code identifies an area inundated by 1% annual chance flooding with velocity hazard (wave action); BFEs have been determined. 440 0152 Zone A This code identifies an area inundated by 1% annual chance flooding, for which no BFEs have been deter- mined. 440 0153 Zone AE This code identifies an area inundated by 1% annual chance flooding, for which BFEs have been deter- mined. 440 0154 Zone AO This code identifies an area inundated by 1% annual chance flooding (usually sheet flow on sloping terrain), for which average depths have been determined; flood depths range from 1 to 3 feet. 440 0155 Zone AO (Alluvial Fan) This code identifies an alluvial fan inundated by 1% annual chance flooding (usually sheet flow on sloping terrain), for which average flood depths and velocities have been determined; flood depths range from 1 to 3 feet. 440 0156 Zone AH This code identifies an area inundated by 1% annual chance flooding (usually an area of ponding), for which BFEs have been determined; flood depths range from 1 to 3 feet. Figure 16: Q3-DLG Attribute Coding Position Major Code Minor Code Descriptor Comments Major12/Minor12 (cont'd) 440 0157 Zone A99 This code identifies an area inundated by 1% annual chance flooding, for which no BFEs have been deter- mined. This is an area to be protected from the 1% annual chance flood by a Federal flood protection system under construction. 440 0158 Zone D This code identifies an area of undetermined but possible flood hazards. 440 0159 Zone AR (Future) This code identifies an area inundated by flooding, for which BFEs or average depths have been determined. This is an area that was previously, and will be again, protected from the 1% annual chance flood by a Federal flood protection system and whose restoration is Federally funded and underway. 440 0160 Zone X (0.2% Annual Chance) This code identifies an area inundated by 0.2% annual chance flooding; an area inundated by 1% annual chance flooding with average depths of less than 1 foot or with drainage areas less than 1 square mile; or an area protected by levees from 1% annual chance flooding. 440 0161 Zone X This code identifies an area that is determined to be outside the 1% and 0.2% annual chance floodplains. 440 0170 1% Annual Chance Flood Discharge Contained in Channel This code identifies an area where the 1% annual chance flooding is contained within the channel banks and the channel is too narrow to show to scale. An arbitrary channel width of 3 meters is shown. BFEs are not shown in this area, although they may be reflected on the corresponding profile. It is labeled with the note "1% annual chance flood dis- charge contained in channel." 440 0171 0.2% Annual Chance Flood Discharge Contained in Channel This code identifies an area where the 0.2% annual chance flooding is contained within the channel banks and the channel is too narrow to show to scale. An arbitrary channel width of 3 meters is shown. It is labeled with the note "0.2% annual chance flood discharge contained in channel." Figure 16: Q3-DLG Attribute Coding Position Major Code Minor Code Descriptor Comments Major12/Minor12 (cont'd) 440 0172 Floodway Contained in Channel This code identifies an area where the floodway is contained within the channel banks and the channel is too narrow to show to scale. An arbitrary channel width of 3 meters is shown. BFEs are not shown in this area, although they may be reflected on the corresponding profile. It is labeled with the note "Floodway contained in channel." 440 0175 Flood Prone Area This code identifies an area designated as a "Flood Prone Area" on a map prepared by USGS and the Federal Insurance Administration. This area has been delineated based on available information on past floods. This is an area inundated by 1% annual chance flooding, for which no BFEs have been deter- mined. 440 0176 Area In SFHA This code identifies an area designated as within a "Special Flood Hazard Area" (or SFHA) on a FIRM. This is an area inundated by 1% annual chance flooding for which BFEs or velocity may have been determined. No distinctions are made between the different flood hazard zones that may be included within the SFHA. These may include Zones A, AE, AO, AH, A99, AR, V, or VE. 440 0177 Area Outside SFHA This code identifies an area designated as outside a "Special Flood Hazard Area" (or SFHA) on a FIRM. This is an area inundated by 0.2% annual chance flooding; an area inundated by 1% annual chance flooding with average depths of less than 1 foot or with drainage areas less than 1 square mile; an area protected by levees from 1% annual chance flooding; or an area that is determined to be outside the 1% and 0.2% annual chance floodplains. No distinctions are made between these different conditions. These may include both shaded and unshaded areas of Zone X. 440 0181 Area Not Included This code identifies an area that is located within a community or county that is not mapped on any published FIRM. Figure 16: Q3-DLG Attribute Coding Position Major Code Minor Code Descriptor Comments Major12/Minor12 (cont'd) 440 0191 Area of Undesignated Flood Hazard This code identifies a body of open water, such as a pond, lake, ocean, etc., located within a community's jurisdictional limits, that has no defined flood hazard. FLOODWAY AREAS Major13/Minor13 440 0710 Floodway This code identifies an area that includes the channel of a river or other watercourse and the adjacent land areas that must be reserved in order to discharge the base flood without cumulatively increasing the water-surface elevation by more than a designated height. (Note: This area is normally in Zone AE; therefore, attribute code 440 0153 will also normally be used with this feature.) 440 0712 Flow Easement This code identifies an area within a community, usually bordering a stream, that has more restrictive floodplain development criteria imposed upon it by the governing body (town, city, etc.) than the criteria imposed as a prerequisite to participation in the NFIP. (Note: Unlike the floodway, this area may overlap any other flood zone and will normally be associated with the attribute code for that zone.) 440 0713 State Encroachment Area This code identifies an area within a community, usually bordering a stream, that has more restrictive floodplain development criteria imposed upon it by the state than the criteria imposed as a prerequisite to participation in the NFIP. (Note: Unlike the floodway, this area may overlap any other flood zone and will normally be associated with the attribute code for that zone.) Figure 16: Q3-DLG Attribute Coding Position Major Code Minor Code Descriptor Comments COASTAL BARRIER RESOURCES SYSTEM AREAS Major14/Minor14 440 0162 Inside Coastal Barrier Resources System area This code identifies an area designated as within a Coastal Barrier Resources System area in which flood insurance is unavailable for structures newly built or substantially improved after the Coastal Barrier date. The specific Coastal Barrier designation date is available on the printed FIRM. 440 0163 Outside Coastal Barrier Resources System area This code identifies any area outside a Coastal Barrier Resources System area. Q3-DLG Attribute Code Domain Position Domain Major 1 410 Minor 1 101 or 150 Major 2 410 Minor 2 State FIPS code Major 3 411 Minor 3 County FIPS code Major 4 412 Minor 4 Community ID number Major 5 420 Minor 5 150, 151, 152, 153, 154, or 155 Major 6 421 Minor 6 FIRM panel number Major 7 422 Minor 7 FIRM suffix (as numeric) Major 8 420 Minor 8 170 Major 9 426 Minor 9 Latitude of SE corner of quad Major 10 427 Minor 10 Longitude of SE corner of quad Major 11 428 Minor 11 Quadrangle identifier (11-88) Major 12 440 Minor 12 Zone (150-161, 170-177, 181, or 191) Major 13 440 Minor 13 Floodway type (710, 712, or 713) Major 14 440 Minor 14 COBRA identifier (162 or 163) Figure 17 Part 11 METADATA FILES This section presents an overview of FEMA's Metadata requirements, including sections on why metadata are important, a description of Q3 Flood Data metadata, metadata file naming, and definitions for non-standard field entries. Why Metadata? As part of FEMA's compliance with the Federal Geographic Data Committee's (FGDC) proposed FIPS standards, "metadata," or data about data, have become a significant concern in the storage and distribution of digital data. Metadata provide the user with detailed information concerning data sources, preparers, characteristics, and other pertinent issues, such as data dictionaries. Metadata also provide information about data availability, data applicability (fitness of use), and issues pertaining to access and transfer of data. In sum, Metadata are a necessary component of digital data for three reasons: - metadata maintain data integrity; - metadata provide information for the facilitation of data distribution; - metadata supply information required to process and interpret data from an external source. Metadata standardization is one critical part of the establishment of a National Spatial Data Infrastructure (NSDI) (Executive Order 12906) and the National Geospatial Data Clearinghouse or "Clearinghouse." The Clearinghouse is designed as a distributed network of geospatial data producers, managers, and users linked electronically, through a network such as the Internet. Metadata data standards are designed to provide flexibility for Clearinghouse participants. Among the initial actions for Clearinghouse development is the implementation of "Standardized Documentation of Data." This step calls for the creation of an inventory of currently available digital geospatial data. Following the data inventory, participants are expected to develop a plan, in consultation with FGDC, for Clearinghouse implementation. Procedurally, once an inventory of digital geospatial data has been generated (i.e., Standardized Documentation of Data), an agency must adopt a plan of public access to geospatial data. Concurrent with the creation of public access procedures, an agency must adopt internal procedures to ensure that the agency accesses the Clearinghouse before it expends funds for new data acquisition, in an effort to reduce data redundancy and duplication of efforts. Q3 Flood Data Metadata Description In order to facilitate FEMA's participation in the Clearinghouse and compliance with the FGDC guidelines, a metadata file shall accompany all Q3 Flood Data products. One metadata file shall be produced for each product type for each county that is maintained in digital format. The metadata file shall be in the form of a text file on the electronic medium containing the digital files. It shall follow the format described by the FGDC in Content for Digital Geospatial Data Metadata (Reference 10) and contain all pertinent items. Metadata File Naming The vector Q3 Flood Data metadata files will be named using the same naming convention as the Q3 Flood Data files with the addition of the letter "m" at the end (e.g., c06048m or c06048.dlm). 06ÄÄÄÂÄ c06048ÄÄÄÄÄ 060124ÄÄÄÄÄ 0001b.tif ÀÄ c06048.tfm ÚÄ c06048.e00 ÃÄ c06048m ³ ÃÄ c06048.tab ÃÄ c06048.dat 06ÄÄÄÄÄ c06048ÄÄÄÄÄ ÃÄ c06048.map ÃÄ c06048.ind ÃÄ c06048.id ÃÄ c06048.mim ³ ÃÄ c06048.dlg ÀÄ c06048.dlm Three examples are provided of the metadata that accompany the Q3 Flood Data products: the Q3 Flood Data ARC/INFO Coverage, the Q3 Flood Data MapInfo File, and the Q3-DLG file. These examples may be found in Appendixes A - C. Instructions for entering items that differ between the four files follows. Non-Standard Metadata Entry Definitions Metadata File Name, Data File Name, Metadata Date Information unique to each file and accompanying metadata file. Publication Date/Calendar Date The date the digital files are completed and ready for publication. Year is mandatory, month is optional. County Name The county covered by the digital files. County and State names are provided. Bounding Coordinates The four corners in latitude and longitude of the four outside corners of the 7.5-minute quadrangle sheets that form an even rectangle around the county. If the 7.5-minute quadrangle corners fall in open bodies of water, are mapped on adjacent quads, etc., the corners of the quad will be generated based on the theoretical extent of the 7.5-minute quadrangle area (i.e., the quad outline will be completed and the corners of the completed quad will be used). The bounding coordinates should be the same as the four control points in the Q3-DLG header file. Cross Reference All other available FEMA FIRM data products are referenced as applicable. This may include Q3 ARC/INFO Coverages, Q3 MapInfo files, Q3-DLGs, and DFIRM-DLGs. Source Information This section lists all source documents used to generate the Q3 Flood Data files. It includes hardcopy sources, softcopy sources, and LOMCs. For the vector Q3 Flood Data files, the metadata source list will be the list of hardcopy FIRMs or DFIRMs, any study contractor workmaps or digital files incorporated into the data sets, and any LOMCs that apply to the county. For Q3 Flood Data generated from non-countywide sources (e.g., community based FIRMs, FIRM-DLGs), the metadata source list includes all communities included within the county. For Q3 Flood Data generated from countywide sources (including effective DFIRMs), the list will include all countywide panels. The FIRM source information includes the community name, effective date, scale, list of effective panels, and abbreviation (e.g., FIRM1). With the exception of scale and abbreviation, this information may be obtained from FEMA's Community Information System (CIS). The LOMC source information requirement includes the community name, determination date, title (e.g., LOMA, LOMR-F, etc.), affected panel(s), case number, type (e.g., 218-70), identifier (address, property description, etc.), determination (e.g., BFE Increase, Out as shown, etc.), whether the LOMC is included in the Q3 Flood Data file or not, and an abbreviation (e.g., LOMC1). All LOMCs that affect the county should be listed, whether they are all included or not. This information may also be derived from FEMA's CIS. Process Steps The list of source abbreviations (e.g., FIRM1 - FIRM23 and LOMC1) and a process date (year is mandatory, month is optional) are provided. Object Count For vector Q3 Flood Data files, point and vector object counts are provided for points, lines, and areas. These are derived from the Q3 Flood Data ARC/INFO Coverage. Spatial Reference Information For Q3-DLGs, the UTM zone number is entered. Metadata Date Should be the same date as the publication date. APPENDIX A SAMPLE Q3 FLOOD DATA ARC/INFO COVERAGE METADATA SAMPLE METADATA FILE FOR Q3 ARC/INFO COVERAGE METADATA FILE NAME: c12005m Q3 ARC/INFO COVERAGE: c12005 METADATA DATE: 19951120 FGDC-Compliant Metadata for Q3 ARC/INFO Coverage Identification Information Citation Originator: Federal Emergency Management Agency Publication Date: 1995 Title: Q3 Flood Data, BAY COUNTY, FLORIDA Publication Information Publication Place: Washington, DC Publisher: Federal Emergency Management Agency Description Abstract: 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 earth's surface using the geographic projection and the decimal degree coordinate system. Specifications for the horizontal control of Q3 Flood Data files are consistent with those required for mapping at a scale of 1:24000. 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 Act). 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 flood 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. Time Period of Content Single Date/Time Calendar Date: 1995 Currentness Reference: Publication date Status Progress: Complete Maintenance and Update Frequency: Irregular Spatial Domain Bounding Coordinates West Bounding Coordinate: -86.000 East Bounding Coordinate: -85.375 North Bounding Coordinate: 30.625 South Bounding Coordinate: 29.875 Keywords Theme Theme Keyword Thesaurus: None Theme Keyword: FEMA Flood Hazard Zones Theme Keyword: Q3 Flood Data Theme Keyword: Q3 Coverage Theme Keyword: Special Flood Hazard Areas Theme Keyword: Digital Flood Insurance Rate Maps Place Place Keyword Thesaurus: None Place Keyword: BAY COUNTY Place Keyword: FLORIDA Place Keyword: USA Access Constraints: None Use Constraints: None. Acknowledgment of FEMA would be appreciated in products derived from these data. Point of Contact Contact Organization Primary Contact Organization: Federal Emergency Management Agency, Mitigation Directorate Contact Address Address Type: mailing address Address: 500 C Street, S.W. City: Washington State or Province: District of Columbia Postal Code: 20472 Contact Voice Telephone: 1-800-358-9616 Native Data Set Environment: Original data development environment varies. Additional manipulation, topological structuring, and attribute encoding were undertaken using ARC/INFO software on a UNIX-based workstation. Cross Reference Cross Reference Citation Originator: Federal Emergency Management Agency Publication Date: 1995 Title: Q3 DLG, BAY COUNTY, FL Publication Information Publication Place: Washington, DC Publisher: Federal Emergency Management Agency Cross Reference Citation Originator: Federal Emergency Management Agency Publication Date: 1995 Title: Q3 Raster FIRM, BAY COUNTY, FL Publication Information Publication Place: Washington, DC Publisher: Federal Emergency Management Agency Cross Reference Citation Originator: Federal Emergency Management Agency Publication Date: 1995 Title: EFIRM, BAY COUNTY, FL Publication Information Publication Place: Washington, DC Publisher: Federal Emergency Management Agency Data Quality Information Attribute Accuracy Attribute Accuracy Report: The Q3 Flood Data are countywide vector files derived from FEMA FIRMs. The attribute definitions may be found in the "Q3 Flood Data Specifications." Attribute accuracy was tested by manual comparison of source graphic with hardcopy plots and a symbolized display on an interactive computer system. Selected attributes that could not be visually verified were individually queried. In addition, an ARC/INFO Arc Macro Language (AML) software program was applied to the dataset to test the attributes against a master set of valid attributes for the specific data category and a complete set of valid attribute combinations. (See also Entity Attribute Information.) Logical Consistency Report: Polygon and chain-node topology are present. Certain node-area-line relationships are collected or generated to satisfy topological requirements. Some of these requirements include the following: lines must begin and end at nodes, lines must connect to each other at nodes, lines do not extend through nodes, left and right areas are defined for each line segment and are consistent throughout the files, and the lines representing the limits of the file neatlines are free of gaps. Tests of logical consistency were performed by ARC/INFO software modules. Check plots were made to test for leaks in all internal polygons. Completeness Report: Data completeness for Q3 Flood Data files reflects the content of the source graphic. Features may have been eliminated or generalized on the source graphic, due to scale and legibility constraints. Flood risk data are developed for communities participating in the NFIP for use in insurance rating and for floodplain management. Flood hazard areas are determined using statistical analysis of records of river flow, storm tides, and rainfall; information obtained through consultation with the communities; floodplain topographic surveys; and hydrologic and hydraulic analysis. Both detailed and approximate analyses are employed. Generally, detailed analyses are used to generate flood risk data only for developed or developing areas of communities. For undeveloped areas where little or no development is expected to occur, FEMA uses approximate analyses to generate flood risk data. Typically, only drainage areas that are greater than one square mile are studied. Q3 Flood Data may be derived from DFIRM-DLGs, from FIRM-DLGs, or from FIRMs digitized previously for emergency applications, or they may be newly created files. In Q3 Flood Data derived from older data sets, certain items may not have been captured or may have been captured differently from the current Q3 Flood Data specifications. In some cases, preliminary FIRM data have been included in the Q3 Flood Data files. These data have been provided to the community for review and comment, and may be subject to change before their final publication date. In addition, in some cases, areas designated as Flood Prone Areas on maps prepared by USGS and FIA have been included in the Q3 Flood Data files. These areas were delineated based on available information on past floods and are described by a unique attribute code that distinguishes them from areas of 1% annual chance flooding derived from FIRMs. Flood Insurance Rate Maps continually undergo revisions and updates. Some of these revisions are effected by letter (Letter of Map Revision [LOMR], Letter of Map Amendment [LOMA]). Q3 Flood Data may not reflect the most current information or information that is not mappable at the publication scale of the FIRM. To obtain the latest information, contact the address listed under distributor. Positional Accuracy Horizontal Positional Accuracy Horizontal Positional Accuracy Report: Specifications for the digitizing of FIRMs to create the Q3 Flood Data are consistent with those requirements for mapping at a scale of 1:24000. Horizontal control of Q3 Flood Data was established using USGS quadrangle maps at 1:24000 or other standard scales. Users should assess the horizontal positional accuracy of the Q3 Flood Data with regard to the selected base map sources and the requirements of their application. With increased frequency, large-scale spatial data sets are becoming widely available for computer-based geographic information systems. Q3 Flood Data may be used in combination with other digital spatial data; however, users should be aware that scalar enlargements do not enhance the relative accuracy of the Q3 Flood Data. Lineage Source Information Source Citation Originator: Federal Emergency Management Agency Publication Date: 19920602 Title: Flood Insurance Rate Map, BAY COUNTY (Unincorporated Areas), FL Geospatial Data Presentation Form: map Publication Information Publication Place: Washington, DC Publisher: Federal Emergency Management Agency Other Citation Details Panel: 1200040000 Panel: 1200040010D Panel: 1200040015D Panel: 1200040016D Panel: 1200040017D Panel: 1200040018D Panel: 1200040019D Panel: 1200040050D Panel: 1200040075D Panel: 1200040100D Panel: 1200040125D Panel: 1200040131D Panel: 1200040132D Panel: 1200040135D Panel: 1200040139D Panel: 1200040145D Panel: 1200040150D Panel: 1200040165E Panel: 1200040175D Panel: 1200040180D Panel: 1200040185D Panel: 1200040190D Panel: 1200040195D Panel: 1200040205D Panel: 1200040210D Panel: 1200040215D Panel: 1200040220D Panel: 1200040230D Panel: 1200040233D Panel: 1200040234D Panel: 1200040235D Panel: 1200040240D Panel: 1200040241D Panel: 1200040242D Panel: 1200040243D Panel: 1200040244D Panel: 1200040252D Panel: 1200040255D Panel: 1200040256D Panel: 1200040260D Panel: 1200040261D Panel: 1200040275D Panel: 1200040285D Panel: 1200040305D Panel: 1200040310D Panel: 1200040320D Panel: 1200040330D Panel: 1200040335D Panel: 1200040340E Panel: 1200040345E Panel: 1200040351D Panel: 1200040352D Panel: 1200040353D Panel: 1200040354D Panel: 1200040357D Panel: 1200040358D Panel: 1200040360D Panel: 1200040362D Panel: 1200040364D Panel: 1200040365D Panel: 1200040366D Panel: 1200040368D Panel: 1200040370D Panel: 1200040390D Panel: 1200040400D Panel: 1200040405E Panel: 1200040410E Panel: 1200040430E Panel: 1200040435D Panel: 1200040440E Panel: 1200040445E Panel: 1200040455D Panel: 1200040460D Panel: 1200040465D Panel: 1200040470D Panel: 1200040485E Panel: 1200040505E Panel: 1200040510E Source Scale Denominators: 6000, 12000, 24000 Type of Source Media: paper Source Time Period of Content Single Date/Time Calendar Date: 19920602 Source Currentness Reference: Effective Date Source Citation Abbreviation: FIRM2 Source Contribution: spatial and attribute information Source Information Source Citation Originator: Federal Emergency Management Agency Publication Date: 19860430 Title: Flood Insurance Rate Map, CITY OF CALLAWAY, FL Geospatial Data Presentation Form: map Publication Information Publication Place: Washington, DC Publisher: Federal Emergency Management Agency Other Citation Details Panel: 1200050000 Panel: 1200050001C Panel: 1200050002C Source Scale Denominator: 6000 Type of Source Media: paper Source Time Period of Content Single Date/Time Calendar Date: 19860430 Source Currentness Reference: Effective Date Source Citation Abbreviation: FIRM3 Source Contribution: spatial and attribute information Source Information Source Citation Originator: Federal Emergency Management Agency Publication Date: 19801205 Title: Flood Insurance Rate Map, TOWN OF CEDAR GROVE, FL Geospatial Data Presentation Form: map Publication Information Publication Place: Washington, DC Publisher: Federal Emergency Management Agency Other Citation Details Panel: 1200060001B Source Scale Denominator: 12000 Type of Source Media: paper Source Time Period of Content Single Date/Time Calendar Date: 19801205 Source Currentness Reference: Effective Date Source Citation Abbreviation: FIRM4 Source Contribution: spatial and attribute information Source Information Source Citation Originator: Federal Emergency Management Agency Publication Date: 19860430 Title: Flood Insurance Rate Map, CITY OF LYNN HAVEN, FL Geospatial Data Presentation Form: map Publication Information Publication Place: Washington, DC Publisher: Federal Emergency Management Agency Other Citation Details Panel: 1200090005D Source Scale Denominator: 12000 Type of Source Media: paper Source Time Period of Content Single Date/Time Calendar Date: 19860430 Source Currentness Reference: Effective Date Source Citation Abbreviation: FIRM5 Source Contribution: spatial and attribute information Source Information Source Citation Originator: Federal Emergency Management Agency Publication Date: 19860103 Title: Flood Insurance Rate Map, CITY OF MEXICO BEACH, FL Geospatial Data Presentation Form: map Publication Information Publication Place: Washington, DC Publisher: Federal Emergency Management Agency Other Citation Details Panel: 1200100001D Source Scale Denominator: 6000 Type of Source Media: paper Source Time Period of Content Single Date/Time Calendar Date: 19860103 Source Currentness Reference: Effective Date Source Citation Abbreviation: FIRM6 Source Contribution: spatial and attribute information Source Information Source Citation Originator: Federal Emergency Management Agency Publication Date: 19860103 Title: Flood Insurance Rate Map, CITY OF PANAMA CITY BEACH, FL Geospatial Data Presentation Form: map Publication Information Publication Place: Washington, DC Publisher: Federal Emergency Management Agency Other Citation Details Panel: 1200130000 Panel: 1200130005C Panel: 1200130010C Source Scale Denominator: 12000 Type of Source Media: paper Source Time Period of Content Single Date/Time Calendar Date: 19860103 Source Currentness Reference: Effective Date Source Citation Abbreviation: FIRM7 Source Contribution: spatial and attribute information Source Information Source Citation Originator: Federal Emergency Management Agency Publication Date: 19860103 Title: Flood Insurance Rate Map, CITY OF PANAMA CITY, FL Geospatial Data Presentation Form: map Publication Information Publication Place: Washington, DC Publisher: Federal Emergency Management Agency Other Citation Details Panel: 1200120000 Panel: 1200120005D Panel: 1200120010D Source Scale Denominator: 12000 Type of Source Media: paper Source Time Period of Content Single Date/Time Calendar Date: 19860103 Source Currentness Reference: Effective Date Source Citation Abbreviation: FIRM8 Source Contribution: spatial and attribute information Source Information Source Citation Originator: Federal Emergency Management Agency Publication Date: 19860430 Title: Flood Insurance Rate Map, CITY OF PARKER, FL Geospatial Data Presentation Form: map Publication Information Publication Place: Washington, DC Publisher: Federal Emergency Management Agency Other Citation Details Panel: 1200110001B Source Scale Denominator: 6000 Type of Source Media: paper Source Time Period of Content Single Date/Time Calendar Date: 19860430 Source Currentness Reference: Effective Date Source Citation Abbreviation: FIRM9 Source Contribution: spatial and attribute information Source Information Source Citation Originator: Federal Emergency Management Agency Publication Date: 19810817 Title: Flood Insurance Rate Map, CITY OF SPRINGFIELD, FL Geospatial Data Presentation Form: map Publication Information Publication Place: Washington, DC Publisher: Federal Emergency Management Agency Other Citation Details Panel: 1200140001B Source Scale Denominator: 6000 Type of Source Media: paper Source Time Period of Content Single Date/Time Calendar Date: 19810817 Source Currentness Reference: Effective Date Source Citation Abbreviation: FIRM10 Source Contribution: spatial and attribute information Source Information Source Citation Originator: Federal Emergency Management Agency Publication Date: 19860306 Title: 102, CITY OF SPRINGFIELD, FL Geospatial Data Presentation Form: map Publication Information Publication Place: Washington, DC Publisher: Federal Emergency Management Agency Other Citation Details: Panel: 1200140001B Case No.: Type: 102 Identifier: WATSON BAYOU TRIBUTARY Included in Q3?: Yes Flooding Source: WATSON BAYOU TRIBUTARY Determination: SUSPENDED Type of Source Media: Paper Source Time Period of content Single Date/Time Calendar Date: 19860306 Source Currentness Reference: Determination Date Source Citation Abbreviation: LOMC1 Source Contribution: spatial and attribute information Process Step Process Description: Q3 Flood Data were produced by either scanning and vectorizing or manually digitizing a hardcopy version of the graphic materials. The scanning and vectorization process captured the digital data as raster data that were vectorized and attributed on an interactive editing station. The manual digitizing process used a digitizing table to capture the digital data; attribution was performed either as the data were digitized or on an interactive edit station after the digitizing was completed. The determination of the production methodology was based on various criteria, including availability of production 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 digital data to the Universal Transverse Mercator (UTM) grid coordinates. An ARC/INFO coverage of the Q3 Flood Data was generated and used to create the Q3-DLG file. The Q3 Flood Data were checked for position and attribute accuracy by comparing plots of the digital data to the source graphic and by symbolized display on an interactive computer system. Selected attributes that could not be visually verified were individually queried. In addition, an ARC/INFO Arc Macro Language (AML) software program was applied to the dataset to test the attributes against a master set of valid attributes for the specific data category and a complete set of valid attribute combinations. Source graphics were revised to reflect updates effected by Letters of Map Change (Letter of Map Revision [LOMR], Letter of Map Amendment [LOMA]). These revisions were included in the Q3 Flood Data if they were mappable at the publication scale of the source graphic. Once final, the ARC/INFO coverage was projected into a geographic grid system, using decimal degree latitude and longitude coordinates and then converted into an ARC/INFO Export file and MapInfo native table files. In addition, the ARC/INFO coverage in UTM coordinates was converted into a Digital Line Graph file. All final files were checked for logical consistency and completeness. Source Contribution: spatial and attribute information Source Used Citation Abbreviation: FIRM1-FIRM10, LOMC1 Process Date: 1995 Spatial Data Organization Information Direct Spatial Reference Method: Vector Point and Vector Object Information SDTS Terms Description SDTS Point and Vector Object Type: Point Point and Vector Object Count: 2011 SDTS Point and Vector Object Type: String Point and Vector Object Count: 4791 SDTS Point and Vector Object Type: GT-polygon composed of chains Point and Vector Object Count: 2012 Spatial Reference Information Horizontal Coordinate System Definition Geographic Latitude Resolution: .000009 Longitude Resolution: .000009 Geographic Coordinate Units: Decimal Degrees Geodetic Model Horizontal Datum Name: North American Datum of 1927 Ellipsoid Name: Clarke 1866 Semi-major Axis: 6378206.4 Denominator of Flattening Ratio: 294.98 Entity/Attribute Information Overview Description Entity and Attribute Overview: In addition to locational and topological information, Q3 Flood Data elements are explicitly encoded using attribute items. Each attribute item identifies characteristics about the Flood Hazard Area, COBRA, Floodway, Political Jurisdiction, Quadrangle, or FIRM panel. All polygon data elements may be encoded with one or more feature characteristics. Entity and Attribute Detail Citation: The FEMA "Q3 Flood Data Specifications" contains a detailed description of each attribute code and a reference to other relevant information. Detailed Description Number of Attributes in Entity: 21 Entity Type Entity Type label: .PAT Entity Type Definition: Polygon attribute table comprising 21 items. Entity Type Definition Source: FEMA FIRM, digital data sources, or other information as appropriate. Attribute Attribute Label Attribute Definition: Polygon attribute table comprising 21 data fields. Attribute Definition Source: FEMA FIRM, digital data sources, or other information as appropriate. Attribute Attribute Label: AREA Attribute Definition: Area of polygon/region in square coverage units. Attribute Definition Source: Computed Attribute Domain Values Enumerated Domain Enumerated Domain Value: Positive real numbers Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: PERIMETER Attribute Definition: Perimeter of polygon/region in coverage units Attribute Definition Source: Computed Attribute Domain Values Enumerated Domain Enumerated Domain Value: Positive real numbers Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: # Attribute Definition: Internal feature number Attribute Definition Source: Computed Attribute Domain Values Enumerated Domain Enumerated Domain Value: Sequential unique positive integer Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: -ID Attribute Definition: User-assigned feature number Attribute Definition Source: User-defined Attribute Domain Values Enumerated Domain Enumerated Domain Value: Integer Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: FIPS Attribute Definition: Standard 5-digit State and County FIPS codes Attribute Definition Source: Federal Information Processing Standard (FIPS), National Institute of Standards & Technology (NIST) Attribute Domain Values Codeset Domain: Federal Information Processing Standard (FIPS) Codeset Source: National Institute of Standards & Technology (NIST) Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: COMMUNITY Attribute Definition: Identifies a county, city, or other community responsible for floodplain management. Numeric value assigned by FEMA. Attribute Definition Source: FEMA FIRM Attribute Domain Values Range Domain Range Domain Minimum: 0 Range Domain Maximum: 9999 Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: FIRM_PANEL Attribute Definition: Eleven-digit alpha-numeric code identifies portion of community covered or not covered by a FIRM panel. Attribute Definition Source: FEMA FIRM Attribute Domain Values Unrepresentable Domain: Code comprises a unique alpha-numeric sequence based on FIPS and FEMA Community and Panel identification numbers Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: QUAD Attribute Definition: USGS 7.5-minute quadrangle identifier Attribute Definition Source: USGS Quadrangle Index Attribute Domain Values Unrepresentable Domain: Unique sequence based on latitude and longitude Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: ZONE Attribute Definition: Flood hazard zone designation Attribute Definition Source: FEMA FIRM Attribute Domain Values Enumerated Domain Enumerated Domain Value: Multiple Codes--refer to "Q3 Flood Data Specifications" Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: FLOODWAY Attribute Definition: Channel, river, or watercourse reserved for flood discharge. Attribute Definition Source: FEMA FIRM Attribute Domain Values Enumerated Domain Enumerated Domain Value: Multiple Codes--refer to "Q3 Flood Data Specifications" Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: COBRA Attribute Definition: Undeveloped Coastal Barrier Area Attribute Definition Source: FEMA FIRM Attribute Domain Values Enumerated Domain Enumerated Domain Value: Multiple Codes--refer to "Q3 Flood Data Specifications" Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: SFHA Attribute Definition: In/Out of flood zone designation Attribute Definition Source: Determined from data topology Attribute Domain Values Enumerated Domain Enumerated Domain Value: "In" Enumerated Domain Value Definition: Area located within Special Flood Hazard Area (SFHA) Enumerated Domain Value: "Out" Enumerated Domain Value Definition: Area located outside of SFHA or within area not included Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: SYMBOL Attribute Definition: Polygon shade symbols for graphic output Attribute Definition Source: Based on polygon codes Attribute Domain Values Enumerated Domain Enumerated Domain Value: Multiple Codes--refer to "Q3 Flood Data Specifications" Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: PANEL_TYP Attribute Definition: Type of FIRM panel represented Attribute Definition Source: FEMA FIRM Attribute Domain Values Enumerated Domain Enumerated Domain Value: Multiple Codes--refer to "Q3 Flood Data Specifications" Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: ST-FIPS Attribute Definition: State FIPS code Attribute Definition Source: Federal Information Processing Standard (FIPS)-NIST Attribute Domain Values Codeset Domain: Federal Information Processing Standard (FIPS) Codeset Source: National Institute of Standards & Technology (NIST) Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: CO-FIPS Attribute Definition: County FIPS code Attribute Definition Source: Federal Information Processing Standard (FIPS)-NIST Attribute Domain Values Codeset Domain: Federal Information Processing Standard (FIPS) Codeset Source: National Institute of Standards & Technology (NIST) Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: STATE Attribute Definition: State FIPS code Attribute Definition Source: Federal Information Processing Standard (FIPS)-NIST Attribute Domain Values Codeset Domain: Federal Information Processing Standard (FIPS) Codeset Source: National Institute of Standards & Technology (NIST) Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: PCOMM Attribute Definition: FIRM Community/County Identifier Attribute Definition Source: FEMA FIRM Attribute Domain Values Unrepresentable Domain: Code comprises a unique alpha-numeric sequence based on FIPS and FEMA Community and Panel identification numbers Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: PANEL Attribute Definition: FIRM Panel number and suffix Attribute Definition Source: FEMA FIRM Attribute Domain Values Unrepresentable Domain: Unique sequence based on FEMA FIRM Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: LAT Attribute Definition: Origin latitude (degrees) of 7.5-minute quadrangle Attribute Definition Source: USGS Quadrangle Index Attribute Domain Values Range Domain Range Domain Minimum: +0000 Range Domain Maximum: +0090 Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: LONG Attribute Definition: Origin longitude (degrees) of 7.5-minute quadrangle Attribute Definition Source: USGS Quadrangle Index Attribute Domain Values Range Domain Range Domain Minimum: -0180 Range Domain Maximum: +0180 Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: QUAD_UNIT Attribute Definition: Index number to 7.5-minute quadrangle Attribute Definition Source: USGS Quadrangle Index Attribute Domain Values Unrepresentable Domain: Unique numeric sequence Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Distribution Information Distributor Contact Information Contact Organization Primary: Federal Emergency Management Agency, Map Service Center Contact Address Address Type: mailing address Address: P.O. Box 1038 City: Jessup State or Province: Maryland Postal Code: 20794-1038 Contact Voice Telephone: 1-800-358-9616 Contact Instructions: Data requests should include the full name of the community or county and the Flood Insurance Rate Map panel number(s) or the 7.5-minute quadrangle sheet area(s) covered by the request. Distribution Liability: No warranty expressed or implied is made by FEMA regarding the utility of the data on any other system nor shall the act of distribution constitute any such warranty. FEMA will warrant the delivery of this product in a computer-readable format and will offer appropriate adjustment of credit when the product is determined unreadable by correctly adjusted computer input peripherals or when the physical medium is delivered in damaged condition. Requests for adjustment of credit must be made within 90 days from the date of this shipment from the ordering site. Standard Order Process Non-digital Form: Printed Flood Insurance Rate Maps that match this data set are available from FEMA at the Map Service Center, cited above. Digital Form: ARC/INFO Export File Format Digital Transfer Options Online Option Computer Contact Information Network Address Network Resource Name: http://www.fema.gov Dialup Instructions: Access Instructions Online Computer and Operating System: Offline Option Offline Media: CD-ROM Recording Format: ISO 9660 Metadata Reference Information Metadata Date: 19951120 Metadata Contact Contact Organization Primary: Federal Emergency Management Agency, Mitigation Directorate Contact Address: Address Type: mailing address Address: 500 C Street, S.W. City: Washington State or Province: District of Columbia Postal Code: 20472 Contact Voice Telephone: 1-800-358-9616 Metadata Standard Name: FGDC Content Standards for Digital Geospatial Metadata Metadata Standard Version: 19940608 APPENDIX B SAMPLE Q3 FLOOD DATA MAPINFO FILE METADATA SAMPLE METADATA FILE FOR Q3 MAPINFO FILE METADATA FILE NAME: c12005.mim Q3 MAPINFO FILE: c12005p.tab METADATA DATE: 19951120 FGDC-Compliant Metadata for Q3 MapInfo File Identification Information Citation Originator: Federal Emergency Management Agency Publication Date: 1995 Title: Q3 Flood Data, BAY COUNTY, FLORIDA Publication Information Publication Place: Washington, DC Publisher: Federal Emergency Management Agency Description Abstract: 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 earth's surface using the geographic projection and the decimal degree coordinate system. Specifications for the horizontal control of Q3 Flood Data files are consistent with those required for mapping at a scale of 1:24000. 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 Act). 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 flood 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. Time Period of Content Single Date/Time Calendar Date: 1995 Currentness Reference: Publication date Status Progress: Complete Maintenance and Update Frequency: Irregular Spatial Domain Bounding Coordinates West Bounding Coordinate: -86.000 East Bounding Coordinate: -85.375 North Bounding Coordinate: 30.625 South Bounding Coordinate: 29.875 Keywords Theme Theme Keyword Thesaurus: None Theme Keyword: FEMA Flood Hazard Zones Theme Keyword: Q3 Flood Data Theme Keyword: Q3 Coverage Theme Keyword: Special Flood Hazard Areas Theme Keyword: Digital Flood Insurance Rate Maps Place Place Keyword Thesaurus: None Place Keyword: BAY COUNTY Place Keyword: FLORIDA Place Keyword: USA Access Constraints: None Use Constraints: None. Acknowledgment of FEMA would be appreciated in products derived from these data. Point of Contact Contact Organization Primary Contact Organization: Federal Emergency Management Agency, Mitigation Directorate Contact Address Address Type: mailing address Address: 500 C Street, S.W. City: Washington State or Province: District of Columbia Postal Code: 20472 Contact Voice Telephone: 1-800-358-9616 Native Data Set Environment: Original data development environment varies. Additional manipulation, topological structuring, and attribute encoding were undertaken using ARC/INFO software on a UNIX-based workstation. Cross Reference Cross Reference Citation Originator: Federal Emergency Management Agency Publication Date: 1995 Title: Q3 DLG, BAY COUNTY, FL Publication Information Publication Place: Washington, DC Publisher: Federal Emergency Management Agency Cross Reference Citation Originator: Federal Emergency Management Agency Publication Date: 1995 Title: Q3 Raster FIRM, BAY COUNTY, FL Publication Information Publication Place: Washington, DC Publisher: Federal Emergency Management Agency Cross Reference Citation Originator: Federal Emergency Management Agency Publication Date: 1995 Title: EFIRM, BAY COUNTY, FL Publication Information Publication Place: Washington, DC Publisher: Federal Emergency Management Agency Data Quality Information Attribute Accuracy Attribute Accuracy Report: The Q3 Flood Data are countywide vector files derived from FEMA FIRMs. The attribute definitions may be found in the "Q3 Flood Data Specifications." Attribute accuracy was tested by manual comparison of source graphic with hardcopy plots and a symbolized display on an interactive computer system. Selected attributes that could not be visually verified were individually queried. In addition, an ARC/INFO Arc Macro Language (AML) software program was applied to the dataset to test the attributes against a master set of valid attributes for the specific data category and a complete set of valid attribute combinations. (See also Entity Attribute Information.) Logical Consistency Report: Polygon and chain-node topology are present. Certain node-area-line relationships are collected or generated to satisfy topological requirements. Some of these requirements include the following: lines must begin and end at nodes, lines must connect to each other at nodes, lines do not extend through nodes, left and right areas are defined for each line segment and are consistent throughout the files, and the lines representing the limits of the file neatlines are free of gaps. Tests of logical consistency were performed by ARC/INFO software modules. Check plots were made to test for leaks in all internal polygons. Completeness Report: Data completeness for Q3 Flood Data files reflects the content of the source graphic. Features may have been eliminated or generalized on the source graphic, due to scale and legibility constraints. Flood risk data are developed for communities participating in the NFIP for use in insurance rating and for floodplain management. Flood hazard areas are determined using statistical analysis of records of river flow, storm tides, and rainfall; information obtained through consultation with the communities; floodplain topographic surveys; and hydrologic and hydraulic analysis. Both detailed and approximate analyses are employed. Generally, detailed analyses are used to generate flood risk data only for developed or developing areas of communities. For undeveloped areas where little or no development is expected to occur, FEMA uses approximate analyses to generate flood risk data. Typically, only drainage areas that are greater than one square mile are studied. Q3 Flood Data may be derived from DFIRM-DLGs, from FIRM-DLGs, or from FIRMs digitized previously for emergency applications, or they may be newly created files. In Q3 Flood Data derived from older data sets, certain items may not have been captured or may have been captured differently from the current Q3 Flood Data specifications. In some cases, preliminary FIRM data have been included in the Q3 Flood Data files. These data have been provided to the community for review and comment, and may be subject to change before their final publication date. In addition, in some cases, areas designated as Flood Prone Areas on maps prepared by USGS and FIA have been included in the Q3 Flood Data files. These areas were delineated based on available information on past floods and are described by a unique attribute code that distinguishes them from areas of 1% annual chance flooding derived from FIRMs. Flood Insurance Rate Maps continually undergo revisions and updates. Some of these revisions are effected by letter (Letter of Map Revision [LOMR], Letter of Map Amendment [LOMA]). Q3 Flood Data may not reflect the most current information or information that is not mappable at the publication scale of the FIRM. To obtain the latest information, contact the address listed under distributor. Positional Accuracy Horizontal Positional Accuracy Horizontal Positional Accuracy Report: Specifications for the digitizing of FIRMs to create the Q3 Flood Data are consistent with those requirements for mapping at a scale of 1:24000. Horizontal control of Q3 Flood Data was established using USGS quadrangle maps at 1:24000 or other standard scales. Users should assess the horizontal positional accuracy of the Q3 Flood Data with regard to the selected base map sources and the requirements of their application. With increased frequency, large-scale spatial data sets are becoming widely available for computer-based geographic information systems. Q3 Flood Data may be used in combination with other digital spatial data; however, users should be aware that scalar enlargements do not enhance the relative accuracy of the Q3 Flood Data. Lineage Source Information Source Citation Originator: Federal Emergency Management Agency Publication Date: 19920602 Title: Flood Insurance Rate Map, BAY COUNTY (Unincorporated Areas), FL Geospatial Data Presentation Form: map Publication Information Publication Place: Washington, DC Publisher: Federal Emergency Management Agency Other Citation Details Panel: 1200040000 Panel: 1200040010D Panel: 1200040015D Panel: 1200040016D Panel: 1200040017D Panel: 1200040018D Panel: 1200040019D Panel: 1200040050D Panel: 1200040075D Panel: 1200040100D Panel: 1200040125D Panel: 1200040131D Panel: 1200040132D Panel: 1200040135D Panel: 1200040139D Panel: 1200040145D Panel: 1200040150D Panel: 1200040165E Panel: 1200040175D Panel: 1200040180D Panel: 1200040185D Panel: 1200040190D Panel: 1200040195D Panel: 1200040205D Panel: 1200040210D Panel: 1200040215D Panel: 1200040220D Panel: 1200040230D Panel: 1200040233D Panel: 1200040234D Panel: 1200040235D Panel: 1200040240D Panel: 1200040241D Panel: 1200040242D Panel: 1200040243D Panel: 1200040244D Panel: 1200040252D Panel: 1200040255D Panel: 1200040256D Panel: 1200040260D Panel: 1200040261D Panel: 1200040275D Panel: 1200040285D Panel: 1200040305D Panel: 1200040310D Panel: 1200040320D Panel: 1200040330D Panel: 1200040335D Panel: 1200040340E Panel: 1200040345E Panel: 1200040351D Panel: 1200040352D Panel: 1200040353D Panel: 1200040354D Panel: 1200040357D Panel: 1200040358D Panel: 1200040360D Panel: 1200040362D Panel: 1200040364D Panel: 1200040365D Panel: 1200040366D Panel: 1200040368D Panel: 1200040370D Panel: 1200040390D Panel: 1200040400D Panel: 1200040405E Panel: 1200040410E Panel: 1200040430E Panel: 1200040435D Panel: 1200040440E Panel: 1200040445E Panel: 1200040455D Panel: 1200040460D Panel: 1200040465D Panel: 1200040470D Panel: 1200040485E Panel: 1200040505E Panel: 1200040510E Source Scale Denominators: 6000, 12000, 24000 Type of Source Media: paper Source Time Period of Content Single Date/Time Calendar Date: 19920602 Source Currentness Reference: Effective Date Source Citation Abbreviation: FIRM2 Source Contribution: spatial and attribute information Source Information Source Citation Originator: Federal Emergency Management Agency Publication Date: 19860430 Title: Flood Insurance Rate Map, CITY OF CALLAWAY, FL Geospatial Data Presentation Form: map Publication Information Publication Place: Washington, DC Publisher: Federal Emergency Management Agency Other Citation Details Panel: 1200050000 Panel: 1200050001C Panel: 1200050002C Source Scale Denominator: 6000 Type of Source Media: paper Source Time Period of Content Single Date/Time Calendar Date: 19860430 Source Currentness Reference: Effective Date Source Citation Abbreviation: FIRM3 Source Contribution: spatial and attribute information Source Information Source Citation Originator: Federal Emergency Management Agency Publication Date: 19801205 Title: Flood Insurance Rate Map, TOWN OF CEDAR GROVE, FL Geospatial Data Presentation Form: map Publication Information Publication Place: Washington, DC Publisher: Federal Emergency Management Agency Other Citation Details Panel: 1200060001B Source Scale Denominator: 12000 Type of Source Media: paper Source Time Period of Content Single Date/Time Calendar Date: 19801205 Source Currentness Reference: Effective Date Source Citation Abbreviation: FIRM4 Source Contribution: spatial and attribute information Source Information Source Citation Originator: Federal Emergency Management Agency Publication Date: 19860430 Title: Flood Insurance Rate Map, CITY OF LYNN HAVEN, FL Geospatial Data Presentation Form: map Publication Information Publication Place: Washington, DC Publisher: Federal Emergency Management Agency Other Citation Details Panel: 1200090005D Source Scale Denominator: 12000 Type of Source Media: paper Source Time Period of Content Single Date/Time Calendar Date: 19860430 Source Currentness Reference: Effective Date Source Citation Abbreviation: FIRM5 Source Contribution: spatial and attribute information Source Information Source Citation Originator: Federal Emergency Management Agency Publication Date: 19860103 Title: Flood Insurance Rate Map, CITY OF MEXICO BEACH, FL Geospatial Data Presentation Form: map Publication Information Publication Place: Washington, DC Publisher: Federal Emergency Management Agency Other Citation Details Panel: 1200100001D Source Scale Denominator: 6000 Type of Source Media: paper Source Time Period of Content Single Date/Time Calendar Date: 19860103 Source Currentness Reference: Effective Date Source Citation Abbreviation: FIRM6 Source Contribution: spatial and attribute information Source Information Source Citation Originator: Federal Emergency Management Agency Publication Date: 19860103 Title: Flood Insurance Rate Map, CITY OF PANAMA CITY BEACH, FL Geospatial Data Presentation Form: map Publication Information Publication Place: Washington, DC Publisher: Federal Emergency Management Agency Other Citation Details Panel: 1200130000 Panel: 1200130005C Panel: 1200130010C Source Scale Denominator: 12000 Type of Source Media: paper Source Time Period of Content Single Date/Time Calendar Date: 19860103 Source Currentness Reference: Effective Date Source Citation Abbreviation: FIRM7 Source Contribution: spatial and attribute information Source Information Source Citation Originator: Federal Emergency Management Agency Publication Date: 19860103 Title: Flood Insurance Rate Map, CITY OF PANAMA CITY, FL Geospatial Data Presentation Form: map Publication Information Publication Place: Washington, DC Publisher: Federal Emergency Management Agency Other Citation Details Panel: 1200120000 Panel: 1200120005D Panel: 1200120010D Source Scale Denominator: 12000 Type of Source Media: paper Source Time Period of Content Single Date/Time Calendar Date: 19860103 Source Currentness Reference: Effective Date Source Citation Abbreviation: FIRM8 Source Contribution: spatial and attribute information Source Information Source Citation Originator: Federal Emergency Management Agency Publication Date: 19860430 Title: Flood Insurance Rate Map, CITY OF PARKER, FL Geospatial Data Presentation Form: map Publication Information Publication Place: Washington, DC Publisher: Federal Emergency Management Agency Other Citation Details Panel: 1200110001B Source Scale Denominator: 6000 Type of Source Media: paper Source Time Period of Content Single Date/Time Calendar Date: 19860430 Source Currentness Reference: Effective Date Source Citation Abbreviation: FIRM9 Source Contribution: spatial and attribute information Source Information Source Citation Originator: Federal Emergency Management Agency Publication Date: 19810817 Title: Flood Insurance Rate Map, CITY OF SPRINGFIELD, FL Geospatial Data Presentation Form: map Publication Information Publication Place: Washington, DC Publisher: Federal Emergency Management Agency Other Citation Details Panel: 1200140001B Source Scale Denominator: 6000 Type of Source Media: paper Source Time Period of Content Single Date/Time Calendar Date: 19810817 Source Currentness Reference: Effective Date Source Citation Abbreviation: FIRM10 Source Contribution: spatial and attribute information Source Information Source Citation Originator: Federal Emergency Management Agency Publication Date: 19860306 Title: 102, CITY OF SPRINGFIELD, FL Geospatial Data Presentation Form: map Publication Information Publication Place: Washington, DC Publisher: Federal Emergency Management Agency Other Citation Details: Panel: 1200140001B Case No.: Type: 102 Identifier: WATSON BAYOU TRIBUTARY Included in Q3?: Yes Flooding Source: WATSON BAYOU TRIBUTARY Determination: SUSPENDED Type of Source Media: Paper Source Time Period of content Single Date/Time Calendar Date: 19860306 Source Currentness Reference: Determination Date Source Citation Abbreviation: LOMC1 Source Contribution: spatial and attribute information Process Step Process Description: Q3 Flood Data were produced by either scanning and vectorizing or manually digitizing a hardcopy version of the graphic materials. The scanning and vectorization process captured the digital data as raster data that were vectorized and attributed on an interactive editing station. The manual digitizing process used a digitizing table to capture the digital data; attribution was performed either as the data were digitized or on an interactive edit station after the digitizing was completed. The determination of the production methodology was based on various criteria, including availability of production 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 digital data to the Universal Transverse Mercator (UTM) grid coordinates. An ARC/INFO coverage of the Q3 Flood Data was generated and used to create the Q3-DLG file. The Q3 Flood Data were checked for position and attribute accuracy by comparing plots of the digital data to the source graphic and by symbolized display on an interactive computer system. Selected attributes that could not be visually verified were individually queried. In addition, an ARC/INFO Arc Macro Language (AML) software program was applied to the dataset to test the attributes against a master set of valid attributes for the specific data category and a complete set of valid attribute combinations. Source graphics were revised to reflect updates effected by Letters of Map Change (Letter of Map Revision [LOMR], Letter of Map Amendment [LOMA]). These revisions were included in the Q3 Flood Data if they were mappable at the publication scale of the source graphic. Once final, the ARC/INFO coverage was projected into a geographic grid system, using decimal degree latitude and longitude coordinates and then converted into an ARC/INFO Export file and MapInfo native table files. In addition, the ARC/INFO coverage in UTM coordinates was converted into a Digital Line Graph file. All final files were checked for logical consistency and completeness. Source Contribution: spatial and attribute information Source Used Citation Abbreviation: FIRM1-FIRM10, LOMC1 Process Date: 1995 Spatial Data Organization Information Direct Spatial Reference Method: Vector Point and Vector Object Information SDTS Terms Description SDTS Point and Vector Object Type: Point Point and Vector Object Count: 2011 SDTS Point and Vector Object Type: String Point and Vector Object Count: 4791 SDTS Point and Vector Object Type: GT-polygon composed of chains Point and Vector Object Count: 2012 Spatial Reference Information Horizontal Coordinate System Definition Geographic Latitude Resolution: .000009 Longitude Resolution: .000009 Geographic Coordinate Units: Decimal Degrees Geodetic Model Horizontal Datum Name: North American Datum of 1927 Ellipsoid Name: Clarke 1866 Semi-major Axis: 6378206.4 Denominator of Flattening Ratio: 294.98 Entity/Attribute Information Overview Description Entity and Attribute Overview: In addition to locational and topological information, Q3 Flood Data elements are explicitly encoded using attribute items. Each attribute item identifies characteristics about the Flood Hazard Area, COBRA, Floodway, Political Jurisdiction, Quadrangle, or FIRM panel. All polygon data elements may be encoded with one or more feature characteristics. Entity and Attribute Detail Citation: The FEMA "Q3 Flood Data Specifications" contains a detailed description of each attribute code and a reference to other relevant information. Detailed Description Number of Attributes in Entity: 21 Entity Type Entity Type label: .PAT Entity Type Definition: Polygon attribute table comprising 21 items. Entity Type Definition Source: FEMA FIRM, digital data sources, or other information as appropriate. Attribute Attribute Label Attribute Definition: Polygon attribute table comprising 21 data fields. Attribute Definition Source: FEMA FIRM, digital data sources, or other information as appropriate. Attribute Attribute Label: AREA Attribute Definition: Area of polygon/region in square coverage units. Attribute Definition Source: Computed Attribute Domain Values Enumerated Domain Enumerated Domain Value: Positive real numbers Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: PERIMETER Attribute Definition: Perimeter of polygon/region in coverage units Attribute Definition Source: Computed Attribute Domain Values Enumerated Domain Enumerated Domain Value: Positive real numbers Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: # Attribute Definition: Internal feature number Attribute Definition Source: Computed Attribute Domain Values Enumerated Domain Enumerated Domain Value: Sequential unique positive integer Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: -ID Attribute Definition: User-assigned feature number Attribute Definition Source: User-defined Attribute Domain Values Enumerated Domain Enumerated Domain Value: Integer Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: FIPS Attribute Definition: Standard 5-digit State and County FIPS codes Attribute Definition Source: Federal Information Processing Standard (FIPS), National Institute of Standards & Technology (NIST) Attribute Domain Values Codeset Domain: Federal Information Processing Standard (FIPS) Codeset Source: National Institute of Standards & Technology (NIST) Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: COMMUNITY Attribute Definition: Identifies a county, city, or other community responsible for floodplain management. Numeric value assigned by FEMA. Attribute Definition Source: FEMA FIRM Attribute Domain Values Range Domain Range Domain Minimum: 0 Range Domain Maximum: 9999 Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: FIRM_PANEL Attribute Definition: Eleven-digit alpha-numeric code identifies portion of community covered or not covered by a FIRM panel. Attribute Definition Source: FEMA FIRM Attribute Domain Values Unrepresentable Domain: Code comprises a unique alpha-numeric sequence based on FIPS and FEMA Community and Panel identification numbers Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: QUAD Attribute Definition: USGS 7.5-minute quadrangle identifier Attribute Definition Source: USGS Quadrangle Index Attribute Domain Values Unrepresentable Domain: Unique sequence based on latitude and longitude Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: ZONE Attribute Definition: Flood hazard zone designation Attribute Definition Source: FEMA FIRM Attribute Domain Values Enumerated Domain Enumerated Domain Value: Multiple Codes--refer to "Q3 Flood Data Specifications" Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: FLOODWAY Attribute Definition: Channel, river, or watercourse reserved for flood discharge. Attribute Definition Source: FEMA FIRM Attribute Domain Values: Enumerated Domain Enumerated Domain Value: Multiple Codes--refer to "Q3 Flood Data Specifications" Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: COBRA Attribute Definition: Undeveloped Coastal Barrier Area Attribute Definition Source: FEMA FIRM Attribute Domain Values Enumerated Domain Enumerated Domain Value: Multiple Codes--refer to "Q3 Flood Data Specifications" Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: SFHA Attribute Definition: In/Out of flood zone designation Attribute Definition Source: Determined from data topology Attribute Domain Values Enumerated Domain Enumerated Domain Value: "In" Enumerated Domain Value Definition: Area located within Special Flood Hazard Area (SFHA) Enumerated Domain Value: "Out" Enumerated Domain Value Definition: Area located outside of SFHA or within area not included Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: SYMBOL Attribute Definition: Polygon shade symbols for graphic output Attribute Definition Source: Based on polygon codes Attribute Domain Values Enumerated Domain Enumerated Domain Value: Multiple Codes--refer to "Q3 Flood Data Specifications" Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: PANEL_TYP Attribute Definition: Type of FIRM panel represented Attribute Definition Source: FEMA FIRM Attribute Domain Values Enumerated Domain Enumerated Domain Value: Multiple Codes--refer to "Q3 Flood Data Specifications" Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: ST-FIPS Attribute Definition: State FIPS code Attribute Definition Source: Federal Information Processing Standard (FIPS)-NIST Attribute Domain Values Codeset Domain: Federal Information Processing Standard (FIPS) Codeset Source: National Institute of Standards & Technology (NIST) Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: CO-FIPS Attribute Definition: County FIPS code Attribute Definition Source: Federal Information Processing Standard (FIPS)-NIST Attribute Domain Values Codeset Domain: Federal Information Processing Standard (FIPS) Codeset Source: National Institute of Standards & Technology (NIST) Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: STATE Attribute Definition: State FIPS code Attribute Definition Source: Federal Information Processing Standard (FIPS)-NIST Attribute Domain Values Codeset Domain: Federal Information Processing Standard (FIPS) Codeset Source: National Institute of Standards & Technology (NIST) Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: PCOMM Attribute Definition: FIRM Community/County Identifier Attribute Definition Source: FEMA FIRM Attribute Domain Values Unrepresentable Domain: Code comprises a unique alpha-numeric sequence based on FIPS and FEMA Community and Panel identification numbers Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: PANEL Attribute Definition: FIRM Panel number and suffix Attribute Definition Source: FEMA FIRM Attribute Domain Values Unrepresentable Domain: Unique sequence based on FEMA FIRM Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: LAT Attribute Definition: Origin latitude (degrees) of 7.5-minute quadrangle Attribute Definition Source: USGS Quadrangle Index Attribute Domain Values Range Domain Range Domain Minimum: +0000 Range Domain Maximum: +0090 Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: LONG Attribute Definition: Origin longitude (degrees) of 7.5-minute quadrangle Attribute Definition Source: USGS Quadrangle Index Attribute Domain Values Range Domain Range Domain Minimum: -0180 Range Domain Maximum: +0180 Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: QUAD_UNIT Attribute Definition: Index number to 7.5-minute quadrangle Attribute Definition Source: USGS Quadrangle Index Attribute Domain Values Unrepresentable Domain: Unique numeric sequence Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Distribution Information Distributor Contact Information Contact Organization Primary: Federal Emergency Management Agency, Map Service Center Contact Address Address Type: mailing address Address: P.O. Box 1038 City: Jessup State or Province: Maryland Postal Code: 20794-1038 Contact Voice Telephone: 1-800-358-9616 Contact Instructions: Data requests should include the full name of the community or county and the Flood Insurance Rate Map panel number(s) or the 7.5-minute quadrangle sheet area(s) covered by the request. Distribution Liability: No warranty expressed or implied is made by FEMA regarding the utility of the data on any other system nor shall the act of distribution constitute any such warranty. FEMA will warrant the delivery of this product in a computer-readable format and will offer appropriate adjustment of credit when the product is determined unreadable by correctly adjusted computer input peripherals or when the physical medium is delivered in damaged condition. Requests for adjustment of credit must be made within 90 days from the date of this shipment from the ordering site. Standard Order Process Non-digital Form: Printed Flood Insurance Rate Maps that match this data set are available from FEMA at the Map Service Center, cited above. Digital Form: MapInfo Native Table Digital Transfer Options Online Option Computer Contact Information Network Address Network Resource Name: http://www.fema.gov Dialup Instructions: Access Instructions Online Computer and Operating System: Offline Option Offline Media: CD-ROM Recording Format: ISO 9660 Metadata Reference Information Metadata Date: 19951120 Metadata Contact Contact Organization Primary: Federal Emergency Management Agency, Mitigation Directorate Contact Address: Address Type: mailing address Address: 500 C Street, S.W. City: Washington State or Province: District of Columbia Postal Code: 20472 Contact Voice Telephone: 1-800-358-9616 Metadata Standard Name: FGDC Content Standards for Digital Geospatial Metadata Metadata Standard Version: 19940608 APPENDIX C SAMPLE Q3 FLOOD DATA DLG METADATA SAMPLE METADATA FILE FOR Q3 DLG FILE METADATA FILE NAME: c12005.dlm Q3 DLG FILE NAME: c12005.dlg METADATA DATE: 19951120 FGDC-Compliant Metadata for Q3 DLG-3 File Identification Information Citation Originator: Federal Emergency Management Agency Publication Date: 1995 Title: Q3 Flood Data, BAY COUNTY, FLORIDA Publication Information Publication Place: Washington, DC Publisher: Federal Emergency Management Agency Description Abstract: 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 earth's surface using the geographic projection and the decimal degree coordinate system. Specifications for the horizontal control of Q3 Flood Data files are consistent with those required for mapping at a scale of 1:24000. 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 Act). 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 flood 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. Time Period of Content Single Date/Time Calendar Date: 1995 Currentness Reference: Publication date Status Progress: Complete Maintenance and Update Frequency: Irregular Spatial Domain Bounding Coordinates West Bounding Coordinate: -86.000 East Bounding Coordinate: -85.375 North Bounding Coordinate: 30.625 South Bounding Coordinate: 29.875 Keywords Theme Theme Keyword Thesaurus: None Theme Keyword: FEMA Flood Hazard Zones Theme Keyword: Q3 Flood Data Theme Keyword: Q3 DLG Theme Keyword: Special Flood Hazard Areas Theme Keyword: Digital Flood Insurance Rate Maps Place Place Keyword Thesaurus: None Place Keyword: BAY COUNTY Place Keyword: FLORIDA Place Keyword: USA Access Constraints: None Use Constraints: None. Acknowledgment of FEMA would be appreciated in products derived from these data. Point of Contact Contact Organization Primary Contact Organization: Federal Emergency Management Agency, Mitigation Directorate Contact Address Address Type: mailing address Address: 500 C Street, S.W. City: Washington State or Province: District of Columbia Postal Code: 20472 Contact Voice Telephone: 1-800-358-9616 Native Data Set Environment: Original data development environment varies. Additional manipulation, topological structuring, and attribute encoding were undertaken using ARC/INFO software on a UNIX-based workstation. Cross Reference Cross Reference Citation Originator: Federal Emergency Management Agency Publication Date: 1995 Title: Q3 Flood Data Coverage, BAY COUNTY, FL Publication Information Publication Place: Washington, DC Publisher: Federal Emergency Management Agency Cross Reference Citation Originator: Federal Emergency Management Agency Publication Date: 1995 Title: Q3 Raster FIRM, BAY COUNTY, FL Publication Information Publication Place: Washington, DC Publisher: Federal Emergency Management Agency Cross Reference Citation Originator: Federal Emergency Management Agency Publication Date: 1995 Title: EFIRM, BAY COUNTY, FL Publication Information Publication Place: Washington, DC Publisher: Federal Emergency Management Agency Data Quality Information Attribute Accuracy Attribute Accuracy Report: The Q3 Flood Data are countywide vector files derived from FEMA FIRMs. The attribute definitions may be found in the "Q3 Flood Data Specifications." Attribute accuracy was tested by manual comparison of source graphic with hardcopy plots and a symbolized display on an interactive computer system. Selected attributes that could not be visually verified were individually queried. In addition, an ARC/INFO Arc Macro Language (AML) software program was applied to the dataset to test the attributes against a master set of valid attributes for the specific data category and a complete set of valid attribute combinations. (See also Entity Attribute Information.) Logical Consistency Report: Polygon and chain-node topology are present. Certain node-area-line relationships are collected or generated to satisfy topological requirements. Some of these requirements include the following: lines must begin and end at nodes, lines must connect to each other at nodes, lines do not extend through nodes, left and right areas are defined for each line segment and are consistent throughout the files, and the lines representing the limits of the file neatlines are free of gaps. Tests of logical consistency were performed by ARC/INFO software modules. Check plots were made to test for leaks in all internal polygons. Completeness Report: Data completeness for Q3 Flood Data files reflects the content of the source graphic. Features may have been eliminated or generalized on the source graphic, due to scale and legibility constraints. Flood risk data are developed for communities participating in the NFIP for use in insurance rating and for floodplain management. Flood hazard areas are determined using statistical analysis of records of river flow, storm tides, and rainfall; information obtained through consultation with the communities; floodplain topographic surveys; and hydrologic and hydraulic analysis. Both detailed and approximate analyses are employed. Generally, detailed analyses are used to generate flood risk data only for developed or developing areas of communities. For undeveloped areas where little or no development is expected to occur, FEMA uses approximate analyses to generate flood risk data. Typically, only drainage areas that are greater than one square mile are studied. Q3 Flood Data may be derived from DFIRM-DLGs, from FIRM-DLGs, or from FIRMs digitized previously for emergency applications, or they may be newly created files. In Q3 Flood Data derived from older data sets, certain items may not have been captured or may have been captured differently from the current Q3 Flood Data specifications. In some cases, preliminary FIRM data have been included in the Q3 Flood Data files. These data have been provided to the community for review and comment, and may be subject to change before their final publication date. In addition, in some cases, areas designated as Flood Prone Areas on maps prepared by USGS and FIA have been included in the Q3 Flood Data files. These areas were delineated based on available information on past floods and are described by a unique attribute code that distinguishes them from areas of 1% annual chance flooding derived from FIRMs. Flood Insurance Rate Maps continually undergo revisions and updates. Some of these revisions are effected by letter (Letter of Map Revision [LOMR], Letter of Map Amendment [LOMA]). Q3 Flood Data may not reflect the most current information or information that is not mappable at the publication scale of the FIRM. To obtain the latest information, contact the address listed under distributor. Positional Accuracy Horizontal Positional Accuracy Horizontal Positional Accuracy Report: Specifications for the digitizing of FIRMs to create the Q3 Flood Data are consistent with those requirements for mapping at a scale of 1:24000. Horizontal control of Q3 Flood Data was established using USGS quadrangle maps at 1:24000 or other standard scales. Users should assess the horizontal positional accuracy of the Q3 Flood Data with regard to the selected base map sources and the requirements of their application. With increased frequency, large-scale spatial data sets are becoming widely available for computer-based geographic information systems. Q3 Flood Data may be used in combination with other digital spatial data; however, users should be aware that scalar enlargements do not enhance the relative accuracy of the Q3 Flood Data. Lineage Source Information Source Citation Originator: Federal Emergency Management Agency Publication Date: 19920602 Title: Flood Insurance Rate Map, BAY COUNTY (Unincorporated Areas), FL Geospatial Data Presentation Form: map Publication Information Publication Place: Washington, DC Publisher: Federal Emergency Management Agency Other Citation Details Panel: 1200040000 Panel: 1200040010D Panel: 1200040015D Panel: 1200040016D Panel: 1200040017D Panel: 1200040018D Panel: 1200040019D Panel: 1200040050D Panel: 1200040075D Panel: 1200040100D Panel: 1200040125D Panel: 1200040131D Panel: 1200040132D Panel: 1200040135D Panel: 1200040139D Panel: 1200040145D Panel: 1200040150D Panel: 1200040165E Panel: 1200040175D Panel: 1200040180D Panel: 1200040185D Panel: 1200040190D Panel: 1200040195D Panel: 1200040205D Panel: 1200040210D Panel: 1200040215D Panel: 1200040220D Panel: 1200040230D Panel: 1200040233D Panel: 1200040234D Panel: 1200040235D Panel: 1200040240D Panel: 1200040241D Panel: 1200040242D Panel: 1200040243D Panel: 1200040244D Panel: 1200040252D Panel: 1200040255D Panel: 1200040256D Panel: 1200040260D Panel: 1200040261D Panel: 1200040275D Panel: 1200040285D Panel: 1200040305D Panel: 1200040310D Panel: 1200040320D Panel: 1200040330D Panel: 1200040335D Panel: 1200040340E Panel: 1200040345E Panel: 1200040351D Panel: 1200040352D Panel: 1200040353D Panel: 1200040354D Panel: 1200040357D Panel: 1200040358D Panel: 1200040360D Panel: 1200040362D Panel: 1200040364D Panel: 1200040365D Panel: 1200040366D Panel: 1200040368D Panel: 1200040370D Panel: 1200040390D Panel: 1200040400D Panel: 1200040405E Panel: 1200040410E Panel: 1200040430E Panel: 1200040435D Panel: 1200040440E Panel: 1200040445E Panel: 1200040455D Panel: 1200040460D Panel: 1200040465D Panel: 1200040470D Panel: 1200040485E Panel: 1200040505E Panel: 1200040510E Source Scale Denominators: 6000, 12000, 24000 Type of Source Media: paper Source Time Period of Content Single Date/Time Calendar Date: 19920602 Source Currentness Reference: Effective Date Source Citation Abbreviation: FIRM2 Source Contribution: spatial and attribute information Source Information Source Citation Originator: Federal Emergency Management Agency Publication Date: 19860430 Title: Flood Insurance Rate Map, CITY OF CALLAWAY, FL Geospatial Data Presentation Form: map Publication Information Publication Place: Washington, DC Publisher: Federal Emergency Management Agency Other Citation Details Panel: 1200050000 Panel: 1200050001C Panel: 1200050002C Source Scale Denominator: 6000 Type of Source Media: paper Source Time Period of Content Single Date/Time Calendar Date: 19860430 Source Currentness Reference: Effective Date Source Citation Abbreviation: FIRM3 Source Contribution: spatial and attribute information Source Information Source Citation Originator: Federal Emergency Management Agency Publication Date: 19801205 Title: Flood Insurance Rate Map, TOWN OF CEDAR GROVE, FL Geospatial Data Presentation Form: map Publication Information Publication Place: Washington, DC Publisher: Federal Emergency Management Agency Other Citation Details Panel: 1200060001B Source Scale Denominator: 12000 Type of Source Media: paper Source Time Period of Content Single Date/Time Calendar Date: 19801205 Source Currentness Reference: Effective Date Source Citation Abbreviation: FIRM4 Source Contribution: spatial and attribute information Source Information Source Citation Originator: Federal Emergency Management Agency Publication Date: 19860430 Title: Flood Insurance Rate Map, CITY OF LYNN HAVEN, FL Geospatial Data Presentation Form: map Publication Information Publication Place: Washington, DC Publisher: Federal Emergency Management Agency Other Citation Details Panel: 1200090005D Source Scale Denominator: 12000 Type of Source Media: paper Source Time Period of Content Single Date/Time Calendar Date: 19860430 Source Currentness Reference: Effective Date Source Citation Abbreviation: FIRM5 Source Contribution: spatial and attribute information Source Information Source Citation Originator: Federal Emergency Management Agency Publication Date: 19860103 Title: Flood Insurance Rate Map, CITY OF MEXICO BEACH, FL Geospatial Data Presentation Form: map Publication Information Publication Place: Washington, DC Publisher: Federal Emergency Management Agency Other Citation Details Panel: 1200100001D Source Scale Denominator: 6000 Type of Source Media: paper Source Time Period of Content Single Date/Time Calendar Date: 19860103 Source Currentness Reference: Effective Date Source Citation Abbreviation: FIRM6 Source Contribution: spatial and attribute information Source Information Source Citation Originator: Federal Emergency Management Agency Publication Date: 19860103 Title: Flood Insurance Rate Map, CITY OF PANAMA CITY BEACH, FL Geospatial Data Presentation Form: map Publication Information Publication Place: Washington, DC Publisher: Federal Emergency Management Agency Other Citation Details Panel: 1200130000 Panel: 1200130005C Panel: 1200130010C Source Scale Denominator: 12000 Type of Source Media: paper Source Time Period of Content Single Date/Time Calendar Date: 19860103 Source Currentness Reference: Effective Date Source Citation Abbreviation: FIRM7 Source Contribution: spatial and attribute information Source Information Source Citation Originator: Federal Emergency Management Agency Publication Date: 19860103 Title: Flood Insurance Rate Map, CITY OF PANAMA CITY, FL Geospatial Data Presentation Form: map Publication Information Publication Place: Washington, DC Publisher: Federal Emergency Management Agency Other Citation Details Panel: 1200120000 Panel: 1200120005D Panel: 1200120010D Source Scale Denominator: 12000 Type of Source Media: paper Source Time Period of Content Single Date/Time Calendar Date: 19860103 Source Currentness Reference: Effective Date Source Citation Abbreviation: FIRM8 Source Contribution: spatial and attribute information Source Information Source Citation Originator: Federal Emergency Management Agency Publication Date: 19860430 Title: Flood Insurance Rate Map, CITY OF PARKER, FL Geospatial Data Presentation Form: map Publication Information Publication Place: Washington, DC Publisher: Federal Emergency Management Agency Other Citation Details Panel: 1200110001B Source Scale Denominator: 6000 Type of Source Media: paper Source Time Period of Content Single Date/Time Calendar Date: 19860430 Source Currentness Reference: Effective Date Source Citation Abbreviation: FIRM9 Source Contribution: spatial and attribute information Source Information Source Citation Originator: Federal Emergency Management Agency Publication Date: 19810817 Title: Flood Insurance Rate Map, CITY OF SPRINGFIELD, FL Geospatial Data Presentation Form: map Publication Information Publication Place: Washington, DC Publisher: Federal Emergency Management Agency Other Citation Details Panel: 1200140001B Source Scale Denominator: 6000 Type of Source Media: paper Source Time Period of Content Single Date/Time Calendar Date: 19810817 Source Currentness Reference: Effective Date Source Citation Abbreviation: FIRM10 Source Contribution: spatial and attribute information Source Information Source Citation Originator: Federal Emergency Management Agency Publication Date: 19860306 Title: 102, CITY OF SPRINGFIELD, FL Geospatial Data Presentation Form: map Publication Information Publication Place: Washington, DC Publisher: Federal Emergency Management Agency Other Citation Details: Panel: 1200140001B Case No.: Type: 102 Identifier: WATSON BAYOU TRIBUTARY Included in Q3?: Yes Flooding Source: WATSON BAYOU TRIBUTARY Determination: SUSPENDED Type of Source Media: Paper Source Time Period of content Single Date/Time Calendar Date: 19860306 Source Currentness Reference: Determination Date Source Citation Abbreviation: LOMC1 Source Contribution: spatial and attribute information Process Step Process Description: Q3 Flood Data were produced by either scanning and vectorizing or manually digitizing a hardcopy version of the graphic materials. The scanning and vectorization process captured the digital data as raster data that were vectorized and attributed on an interactive editing station. The manual digitizing process used a digitizing table to capture the digital data; attribution was performed either as the data were digitized or on an interactive edit station after the digitizing was completed. The determination of the production methodology was based on various criteria, including availability of production 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 digital data to the Universal Transverse Mercator (UTM) grid coordinates. An ARC/INFO coverage of the Q3 Flood Data was generated and used to create the Q3-DLG file. The Q3 Flood Data were checked for position and attribute accuracy by comparing plots of the digital data to the source graphic and by symbolized display on an interactive computer system. Selected attributes that could not be visually verified were individually queried. In addition, an ARC/INFO Arc Macro Language (AML) software program was applied to the dataset to test the attributes against a master set of valid attributes for the specific data category and a complete set of valid attribute combinations. Source graphics were revised to reflect updates effected by Letters of Map Change (Letter of Map Revision [LOMR], Letter of Map Amendment [LOMA]). These revisions were included in the Q3 Flood Data if they were mappable at the publication scale of the source graphic. Once final, the ARC/INFO coverage was projected into a geographic grid system, using decimal degree latitude and longitude coordinates and then converted into an ARC/INFO Export file and MapInfo native table files. In addition, the ARC/INFO coverage in UTM coordinates was converted into a Digital Line Graph file. All final files were checked for logical consistency and completeness. Source Contribution: spatial and attribute information Source Used Citation Abbreviation: FIRM1-FIRM10, LOMC1 Process Date: 1995 Spatial Data Organization Information Direct Spatial Reference Method: Vector Point and Vector Object Information SDTS Terms Description SDTS Point and Vector Object Type: Point Point and Vector Object Count: 2011 SDTS Point and Vector Object Type: String Point and Vector Object Count: 4791 SDTS Point and Vector Object Type: GT-polygon composed of chains Point and Vector Object Count: 2012 Spatial Reference Information Horizontal Coordinate System Definition Planar Grid Coordinate System Grid Coordinate System Name: Universal Transverse Mercator UTM Zone Number: 17 Planar Coordinate Information Planar Coordinate Encoding Method: Coordinate Pair Coordinate Representation Abscissa Resolution: 0.61 Ordinate Resolution: 0.61 Planar Distance Units: meters Geodetic Model Horizontal Datum Name: North American Datum of 1927 Ellipsoid Name: Clarke 1866 Semi-major Axis: 6378206.4 Denominator of Flattening Ratio: 294.98 Entity/Attribute Information Overview Description Entity and Attribute Overview: In addition to locational and topological information, Q3 Flood Data elements are explicitly encoded using 14 MAJOR/MINOR code pairs that identify characteristics about the attribute items. Each attribute item identifies characteristics about the Flood Hazard Area, COBRA, Floodway, Political Jurisdiction, Quadrangle, or FIRM panel. All polygon data elements are encoded with fourteen feature characteristics. Entity and Attribute Detail Citation: The FEMA "Q3 Flood Data Specifications" contains a detailed description of each attribute code and a reference to other relevant information. Detailed Description Number of Attributes in Entity: 28 Entity Type Entity Type label: Flood Hazard Zones Entity Type Definition: Flood Hazard Zones are defined in Q3 Flood Data files by 28 items that describe their Flood Hazard Area, COBRA, Floodway, Political Jurisdiction, Quadrangle, or FIRM Panel. Entity Type Definition Source: FEMA FIRM, digital data sources, or other information as appropriate. Attribute Attribute Label: Flood Hazard Zones Attribute Definition: Data record comprising 28 fields. Attribute Definition Source: FEMA FIRM, digital data sources, or other information as appropriate. Attribute Attribute Label: MAJOR1 Attribute Definition: 3-digit Political Area attribute code Attribute Definition Source: FEMA FIRM, "Q3 Flood Data Specifications" Attribute Domain Values Enumerated Domain Enumerated Domain Value: 410 Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: MINOR1 Attribute Definition: 4-digit Political Area attribute code Attribute Definition Source: FEMA FIRM, "Q3 Flood Data Specifications" Attribute Domain Values Enumerated Domain Enumerated Domain Value: Multiple codes--refer to "Q3 Flood Data Specifications" Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: MAJOR2 Attribute Definition: 3-digit Political Area attribute code: State FIPS Attribute Definition Source: FEMA FIRM, "Q3 Flood Data Specifications" Attribute Domain Values Enumerated Domain Enumerated Domain Value: 410 Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: MINOR2 Attribute Definition: State FIPS code Attribute Definition Source: Federal Information Processing Standard (FIPS)--NIST Attribute Domain Values Codeset Domain: Federal Information Processing Standard (FIPS) Codeset Source: National Institute of Standards & Technology (NIST) Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: MAJOR3 Attribute Definition: 3-digit Political Area attribute code: County or Equivalent FIPS Attribute Definition Source: FEMA FIRM, "Q3 Flood Data Specifications" Attribute Domain Values Enumerated Domain Enumerated Domain Value: 411 Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: MINOR3 Attribute Definition: County or equivalent FIPS code Attribute Definition Source: Federal Information Processing Standard (FIPS)--NIST Attribute Domain Values Codeset Domain: Federal Information Processing Standard (FIPS) Codeset Source: National Institute of Standards & Technology (NIST) Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: MAJOR4 Attribute Definition: 3-digit Political Area attribute code: Community Number Attribute Definition Source: FEMA FIRM, "Q3 Flood Data Specifications" Attribute Domain Values Enumerated Domain Enumerated Domain Value: 412 Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: MINOR4 Attribute Definition: 4-digit Political Area attribute code: Community Number Attribute Definition Source: FEMA FIRM, "Q3 Flood Data Specifications" Attribute Domain Values Unrepresentable Domain: FEMA Community Identification Number Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: MAJOR5 Attribute Definition: 3-digit Map Panel Area attribute code Attribute Definition Source: FEMA FIRM, "Q3 Flood Data Specifications" Attribute Domain Values Enumerated Domain Enumerated Domain Value: 420 Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: MINOR5 Attribute Definition: 4-digit Map Panel Area attribute code Attribute Definition Source: FEMA FIRM, "Q3 Flood Data Specifications" Attribute Domain Values Enumerated Domain Enumerated Domain Value: Multiple codes--refer to "Q3 Flood Data Specifications" Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: MAJOR6 Attribute Definition: 3-digit Map Panel Area attribute code: FIRM Panel Number Attribute Definition Source: FEMA FIRM, "Q3 Flood Data Specifications" Attribute Domain Values Enumerated Domain Enumerated Domain Value: 421 Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: MINOR6 Attribute Definition: 4-digit Map Panel Area attribute code: FIRM Panel Number Attribute Definition Source: FEMA FIRM, "Q3 Flood Data Specifications" Attribute Domain Values Unrepresentable Domain: Unique numeric sequence derived from FIRMs Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: MAJOR7 Attribute Definition: 3-digit Map Panel Area attribute code: FIRM Panel Alpha Character numeric equivalent Attribute Definition Source: FEMA FIRM, "Q3 Flood Data Specifications" Attribute Domain Values Enumerated Domain Enumerated Domain Value: 422 Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: MINOR7 Attribute Definition: 3-digit Map Panel Area attribute code: FIRM Panel Alpha Character numeric equivalent Attribute Definition Source: FEMA FIRM, "Q3 Flood Data Specifications" Attribute Domain Values Range Domain Range Domain Minimum: 0001 [equivalent to "A"] Range Domain Maximum: 0026 [equivalent to "Z"] Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: MAJOR8 Attribute Definition: 3-digit USGS 7.5-minute Quadrangle Area attribute Attribute Definition Source: USGS Quadrangle Index, "Q3 Flood Data Specifications" Attribute Domain Values Enumerated Domain Enumerated Domain Value: 420 Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: MINOR8 Attribute Definition: 3-digit USGS 7.5-minute Quadrangle Area attribute Attribute Definition Source: USGS Quadrangle Index, "Q3 Flood Data Specifications" Attribute Domain Values Enumerated Domain Enumerated Domain Value: 170 Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: MAJOR9 Attribute Definition: 3-digit USGS 7.5-minute Quadrangle Area parameter attribute code: Latitude (degrees) Attribute Definition Source: USGS Quadrangle Index, "Q3 Flood Data Specifications" Attribute Domain Values Enumerated Domain Enumerated Domain Value: 426 Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: MINOR9 Attribute Definition: 4-digit USGS 7.5-minute Quadrangle Area parameter attribute Code: Latitude (degrees) Attribute Definition Source: USGS Quadrangle Index, "Q3 Flood Data Specifications" Attribute Domain Values Range Domain Range Domain Minimum: +0000 Range Domain Maximum: +0090 Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: MAJOR10 Attribute Definition: 3-digit USGS 7.5-minute Quadrangle Area parameter attribute code: Longitude (degrees) Attribute Definition Source: USGS Quadrangle Index, "Q3 Flood Data Specifications" Attribute Domain Values Enumerated Domain Enumerated Domain Value: 427 Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: MINOR10 Attribute Definition: 4-digit USGS 7.5-minute Quadrangle Area parameter attribute code: Longitude (degrees) Attribute Definition Source: USGS Quadrangle Index, "Q3 Flood Data Specifications" Attribute Domain Values Range Domain Range Domain Minimum: -0180 Range Domain Maximum: +0180 Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: MAJOR11 Attribute Definition: 3-digit USGS 7.5-minute Quadrangle Area parameter attribute code: Identifier Attribute Definition Source: USGS Quadrangle Index, "Q3 Flood Data Specifications" Attribute Domain Values Enumerated Domain Enumerated Domain Value: 428 Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: MINOR11 Attribute Definition: 4-digit USGS 7.5-minute Quadrangle Area parameter attribute code: Identifier Attribute Definition Source: USGS Quadrangle Index, "Q3 Flood Data Specifications" Attribute Domain Values Range Domain Range Domain Minimum: 0011 ["A1" numeric equivalent] Range Domain Maximum: 0088 ["H8" numeric equivalent] Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: MAJOR12 Attribute Definition: 3-digit Flood Hazard Zone Area attribute code Attribute Definition Source: FEMA FIRM, "Q3 Flood Data Specifications" Attribute Domain Values Enumerated Domain Enumerated Domain Value: 440 Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: MINOR12 Attribute Definition: 4-digit Flood Hazard Zone Area attribute code Attribute Definition Source: FEMA FIRM, "Q3 Flood Data Specifications" Attribute Domain Values Enumerated Domain Enumerated Domain Value: Multiple codes--refer to "Q3 Flood Data Specifications" Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: MAJOR13 Attribute Definition: 3-digit Flood Hazard Zone Area attribute code: Floodway Attribute Definition Source: FEMA FIRM, "Q3 Flood Data Specifications" Attribute Domain Values Enumerated Domain Enumerated Domain Value: 440 Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: MINOR13 Attribute Definition: 4-digit Flood Hazard Zone Area attribute code: Floodway Attribute Definition Source: FEMA FIRM, "Q3 Flood Data Specifications" Attribute Domain Values Enumerated Domain Enumerated Domain Value: Multiple codes--refer to "Q3 Flood Data Specifications" Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: MAJOR14 Attribute Definition: 3-digit Undeveloped Coastal Barrier Area attribute code: Floodway Attribute Definition Source: FEMA FIRM, "Q3 Flood Data Specifications" Attribute Domain Values Enumerated Domain Enumerated Domain Value: 440 Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Attribute Attribute Label: MINOR14 Attribute Definition: 4-digit Undeveloped Coastal Barrier Area attribute code: Floodway Attribute Definition Source: FEMA FIRM, "Q3 Flood Data Specifications" Attribute Domain Values Enumerated Domain Enumerated Domain Value: Multiple codes--refer to "Q3 Flood Data Specifications" Attribute Value Accuracy Information Attribute Measurement Frequency: Unknown Distribution Information Distributor Contact Information Contact Organization Primary: Federal Emergency Management Agency, Map Service Center Contact Address Address Type: mailing address Address: P.O. Box 1038 City: Jessup State or Province: Maryland Postal Code: 20794-1038 Contact Voice Telephone: 1-800-358-9616 Contact Instructions: Data requests should include the full name of the community or county and the Flood Insurance Rate Map panel number(s) or the 7.5-minute quadrangle sheet area(s) covered by the request. Distribution Liability: No warranty expressed or implied is made by FEMA regarding the utility of the data on any other system nor shall the act of distribution constitute any such warranty. FEMA will warrant the delivery of this product in a computer-readable format and will offer appropriate adjustment of credit when the product is determined unreadable by correctly adjusted computer input peripherals or when the physical medium is delivered in damaged condition. Requests for adjustment of credit must be made within 90 days from the date of this shipment from the ordering site. Standard Order Process Non-digital Form: Printed Flood Insurance Rate Maps that match this data set are available from FEMA at the Map Service Center, cited above. Digital Form: DLG Format Version Number: 3 Format Specification: Optional Digital Transfer Options Online Option Computer Contact Information Network Address Network Resource Name: http://www.fema.gov Dialup Instructions: Access Instructions Online Computer and Operating System: Offline Option Offline Media: CD-ROM Recording Format: ISO 9660 Metadata Reference Information Metadata Date: 19951120 Metadata Contact Contact Organization Primary: Federal Emergency Management Agency, Mitigation Directorate Contact Address: Address Type: mailing address Address: 500 C Street, S.W. City: Washington State or Province: District of Columbia Postal Code: 20472 Contact Voice Telephone: 1-800-358-9616 Metadata Standard Name: FGDC Content Standards for Digital Geospatial Metadata Metadata Standard Version: 19940608 APPENDIX D UTM ZONES Codes for UTM Coordinate Zones West Longitude degrees Zone 180-174 1 174-168 2 168-162 3 162-156 4 156-150 5 150-144 6 144-138 7 138-132 8 132-126 9 126-120 10 120-114 11 114-108 12 108-102 13 102- 96 14 96- 90 15 90- 84 16 84- 78 17 78- 72 18 72- 66 19 66- 60 20 APPENDIX E GLOSSARY OF TERMS AND ACRONYMS GLOSSARY OF TERMS Accuracy - In mapping, the reduction of positional and attribute errors based on information sources and data input instruments. Data precision must reflect, not exceed its accuracy. ARC Macro Language (AML) - A fourth generation programming language with facilities to use named variables, perform logical branching and loops, perform arithmetic and trigonometric operations, make calls and pass variables to other programs, and perform selected Geographic Information Systems operations. It also provides facilities to design and create custom menus. AML is also used to refer to a program written using the ARC macro language. ASCII American Standard Code for Information Exchange - A popular standard for the exchange of alphanumeric data. ARC/INFO - A software package that provides a menu and key-in operator interface with commands for generating, editing, and analyzing graphics and data. It is vector geo-relational software (Environmental Systems Research Institute, Inc., Redlands, CA). Attribute - Descriptive characteristic or quality of a feature. Attributes may be represented by locational or non-locational descriptive information about a feature. Base Flood Elevation (BFE) - The elevation associated with the flood having a one-percent annual chance of being equalled or exceeded in any given year. It is shown on the Flood Insurance Rate Map. Base Map - Map of the community that depicts cultural features (roads, railroad, bridges, dams, culverts, etc.), drainage features, and the corporate limits. Buffer Zone - An area of specified distance (radius) around a map item or items. CCITT Group 4 Compression - An internationally accepted digital file compression scheme for black-and-white (1-bit) TIFF image data. TIFF data may also be stored as uncompressed files. Coastal Barrier Resources System (CBRS) - Areas set aside by the Coastal Barrier Resources Act, an act of Congress, signed into law in 1982 and amended in 1990. The CBRS is comprised of units of land consisting of undeveloped coastal barriers and other areas located on the coast and Great Lakes of the U.S.. Flood insurance is not available for structures built after the coastal barrier was identified. Compact Disk Read Only Memory (CD-ROM) - A digital medium for the storage of data in a standardized format (ISO 9660). Community Identification (CID) - A unique six-digit number assigned to each community by FEMA and used for identity in computer databases; it is shown on the FIS, FIRM, and in the Q3 Flood Data files. The first two digits of the number are always the State FIPS code. Community Rating System (CRS) - A program created by FEMA to provide new incentive for activities that reduce flood losses and support the sale of flood insurance. Any community participating in the NFIP may apply for CRS classification by demonstrating that it is implementing floodplain management and public information activities that exceed the minimum requirements of the NFIP. Once qualified, the community benefits by obtaining flood insurance premium rate credits for its residents. The credits vary by the level of activities undertaken by the community. Control Point - Any station in a horizontal or vertical control network that is identified in a data set or photograph and used for correlating the data shown in the data set or photograph. Coordinate System - A particular kind of reference frame or system, such as plane rectangular coordinates or spherical coordinates, which uses linear or angular values to designate the position of points within that particular reference frame or system, e.g., State Plane, UTM. Database - A collection of information related by a common fact or purpose. Data Capture - Series of operations required to encode data in a computer-readable form (digitizing). Data Layer - Refers to data having similar characteristics being contained in the same plane or overlay (e.g., roads, rivers). Usually information contained in a data layer is related and is designed to be used with other layers. Data Set or Data File - A named collection of logically related data records arranged in a prescribed manner. The physical set of data of one data type being referred to or being used in the context of a data processing operation. Digital Data - Data displayed, recorded, or stored in binary notation. Digital Flood Insurance Rate Map - (DFIRM) - The Digital Flood Insurance Rate Map (DFIRM) is comprised of all digital data required to create the hardcopy FIRM. This includes base map information, graphics, text, shading, and other geographic and graphic data required to create the final hardcopy FIRM product to FEMA standards and specifications. These data serve the purpose of map design and provide the database from which the Digital Line Graph thematic product of the flood risks can be extracted to create the DFIRM-DLG. These products are generally produced in a countywide format. DFIRMs are subjected to community review and approval and are, therefore, the official basis for implementing the regulations and requirements of the NFIP within the community. Digital Flood Insurance Rate Map -DLG (DFIRM - DLG) - This product is created by extracting the flood risk thematic data from the DFIRM. The format of this product is the U.S. Geological Survey Digital Line Graph Level 3 Optional format, as described in the FEMA specifications for digital FIRMs. The DFIRM-DLG does not include base map information, nor does it include graphic data required to create a hardcopy FIRM. This product is intended to be the primary means of transferring flood risk data depicted by FIRMs to GISs through a public domain data exchange format. The DFIRM-DLGs are tiled to the U.S. Geological Survey 1:24,000 scale topographic map series. Digital Line Graph (DLG) - A computer file format for mapping data that provides a topological structure to describe points, lines, and polygons. A DLG may contain lists of point coordinates describing boundaries, drainage lines, and other linear or area features, which are organized by USGS quadrangle areas. These data are the digital equivalent of the linear hydrographic and cultural data on a topographic base map. The flood risk thematic layers developed by FEMA will fit the quadrangle as an overlay. The U.S. Geological Survey Digital Line Graph Level 3 Optional format has been adopted by FEMA for the purposes of the National Flood Insurance Program mapping and engineer requirements. Level 3 data files are fully topologically structured and are designed to be integrated into GISs. Digitizing - A process of converting an analog image or map into a digital format usable by a computer. Edge Matching - The comparison and graphic adjustment of features to obtain agreement along the edges of adjoining map sheets. Elevation Reference Mark (ERM) - A point of vertical ground elevation reference shown on the FIRM for comparison to the BFE. ERMs are referenced to the National Geodetic Vertical Datum (NGVD) or the North American Vertical Datum (NAVD) or an alternative local datum if applicable. Federal Emergency Management Agency (FEMA) - The agency reporting directly to the President and responsible for identifying and mitigating natural and man-made hazards. Federal Geographic Data Committee (FGDC) - An interagency committee, established by the Office of Management and Budget, that promotes the coordinated development, use, sharing, and dissemination of geospatial data on a national basis. The FGDC is composed of representatives from 14 Cabinet level and independent Federal agencies. Federal Information Processing Standards (FIPS) - The official source within the Federal government for information processing standards, which are developed and published by the Institute for Computer Sciences and Technology at the National Institute of Standards and Technology (NIST). Federal Insurance Administration (FIA) - An administration within FEMA that provides flood and crime insurance. Flood Insurance Rate Map (FIRM) - A map on which the 100- and 500-year floodplains, BFEs, and risk premium zones are delineated to enable insurance agents to issue accurate flood insurance policies to homeowners in communities participating in the NFIP. Flood Insurance Study (FIS) - An examination, evaluation, and determination of the flood hazards, and if appropriate, the corresponding water-surface elevations. FIRM-DLG - The FIRM-DLG is a product developed by digitizing and/or scanning the existing hardcopy FIRM to create a thematic overlay of flood risks. These products differ from the DFIRM as they are not tied to a base map, not used to produce a new version of the hardcopy FIRM, and not subjected to community review. FIRM-DLGs are intended to faithfully duplicate the existing hardcopy FIRM and provide users with automated flood risk data that is comparable to what they would derive from the hardcopy FIRM. To this end, edge-matching errors, overlaps and underlaps in coverage, and similar problems are not corrected during digitizing or scanning as they are during the DFIRM-DLG production. Geographic Information System (GIS) - System of computer hardware, software, and procedures designed to support the capture, management, manipulation, analysis, modeling, and display of spatially referenced data for solving complex planning and management problems. Geocoding - Associating either geographic coordinates or grid cell identifiers to data, points, lines, and shapes. Geographic Coordinates - Coordinate system in which horizontal and vertical distances on a planimetric map are represented in units of latitude and longitude rather than feet or meters. Georeference System - An X,Y or X,Y,Z coordinate system that locates points on the surface of the earth as a reference to points on a map. Geo-relational - Geometry of the spatial data. Housed separately from its attributes. Gutter (or Zone Break) - A line shown on the FIRM as a white line within the screened SFHA. This line separates different risk premium zones. Horizontal Control - Network of stations of known geographic or grid positions referred to a common horizontal datum, which controls the horizontal positions of mapped features with respect to parallels and meridians or northing and easting grid lines shown on the map. Layer - Refers to the various "overlays" of data, each of which normally deals with one thematic topic. These overlays are registered to each other by the common coordinate system of the database. In GIS, a layer or a theme represents a specific kind of data. Letter of Map Amendment (LOMA) - An official determination that a specific structure or property is not within the 1% annual chance floodplain; a LOMA amends the effective FIRM. Letter of Map Revision (LOMR) - A letter that revises BFEs, flood hazard zones, floodplain boundaries, or floodways that are shown on an effective FIRM or FBFM. Letter of Map Correction (LOMC) - A term used to refer to all letters that revise FIRMs, both LOMAs and LOMRs. Line - A level of spatial measurement referring to a one-dimensional defined object having a length and direction, and connecting at least two points. Macro - A series of instructions combined to be executed with a single command. MapInfo - A desktop mapping system that combines map graphics and a relational database for cartographic display and spatial analysis (MapInfo Corporation, Troy, NY). Menu- A list of options on a screen display or pallet allowing an operator to select the next operations by indicating one or more choices with a pointing device. Merge - To combine items from two or more similarly ordered sets into one set that is arranged in the same order. In a GIS, to splice separate but adjacent mapped areas into a single data set. Metadata - Literally, metadata are "data about data," or descriptive information about the contents of a digital geospatial data file. Metadata standards have been developed by the FGDC to govern the content and order of the information so that it may be readily queried by users to determine if the data meet their needs. MicroStation - A software package that provides a menu and key-in operator interface with commands for generating and editing graphics and data (Bentley Systems, Inc., Exton, PA). National Flood Insurance Program (NFIP) - The Federal regulatory program under which flood-prone areas are identified and flood insurance is made available to residents of participating communities. Node - A point at which two or more lines meet; called an edge or vertex in graph theory. Operating System - The master control program that governs the operation of a computer system, running job entry, input/output services, data management, and supervision or housekeeping. Planimetric Map - Map representing only horizontal positions from features represented; distinguished from a topographic map by the omission of relief in measurable form. A planimetrically accurate map shows accurate horizontal distances between features. Pixel - Short for "picture element." The smallest discrete element that makes up an image. Point - A level of spatial measurement referring to an object that has no dimension. Point Data - In a vector structure, data consisting of a single, distinct X,Y coordinate pair. In a raster structure, point data are represented by single cells. Polygon - A two-dimensional figure with three or more sides intersecting at a like number of points. In Geographic Information Systems, an area. Projection - The mathematical transformation of three-dimensional space into a two-dimensional (flat) surface. Projection formulae are dependent on a variety of spherical models (spheroids) that distort the spatial characteristics of a location. Quad (also USGS Quad) - A U.S. Geological Survey (USGS) topographic map; Quad stands for "Quadrangle." Quality Assurance/Quality Control (QA/QC) - Intermediate and final review of the FIS and FIRM performed to ensure compliance with FEMA standards. Q3 Flood Data - A digital FIRM product developed and distributed by FEMA. Q3 Flood Data are developed by scanning and vectorizing the existing hardcopy FIRM to create a raster product suitable for viewing or printing, as well as a thematic vector overlay of flood risks. Q3 Flood Data capture all FIRM data in the raster file, but vectorize only certain features. Raster Data - The representation of spatial data as regular grid cells or tessellations. Cells may be subdivided or aggregated depending on the variety and density of features to be modeled. Read Only Memory (ROM) - A microcircuit containing programs or data that cannot be erased. When new data or programs can replace old ones, the microcircuit is called an EROM, for erasable read only memory, or PROM, for programmable read only memory. Record - A groups of items in a file treated as a unit. For example, all data items for a census tract can be grouped as a record and assigned to a single segment of a magnetic tape or other media file for convenient storage and retrieval. Scale - A representative fraction of a paper map distance to ground distance. Example: 1:12,000 is the representative fraction in which one unit of measure on the map is equal to 12,000 of the same units of measure on the ground. FEMA map scales are expressed in a ratio of 1" of map distance equal to a given number of feet on the ground. Scanner - Any device that systematically decomposes a sensed image or scene into pixels and then records some attribute of each pixel. Scanning - Process of using an electronic input device to convert analog information such as maps, photographs, overlays, etc., into a digital format usable by a computer. Spatial Data Transfer Standards (SDTS) - A FIPS standard (FIPS 173) developed as a mechanism for the transfer of digital spatial data between different computer systems. It specifies exchange constructs, addressing formats, structure, and content for spatially referenced vector and raster data. Special Flood Hazard Area (SFHA) - Any area inundated by the base (1% annual chance) flood; these areas are identified on the FIRM as Zones A, AE, AH, AO, AR, A1-30, A99, V, VE, and V1-30. Thematic Layer - A data layer containing selected information relating to a specific theme, such as soils, vegetation, land use, etc. TIFF - Tagged Image File Format, a standard exchange format for raster or image files. Tags or identifiers are used to structure the raster data such that blocks of data may be interpreted based on tags that identify them. TIFF images may be black and white, gray scale, or color, and may be compressed using a variety of compression types. TIGER -- Topologically Integrated Geographic Encoding and Referencing File - The nationwide digital database of planimetric base map features developed by the U.S. Bureau of the Census for the 1990 Census. Topology - A branch of non-euclidean geometry that analyzes the spatial relationships and connectivity of graphs and their components. In GIS, topology is a key element used in a number of data models, such as ARC/INFO. U.S. Geological Survey (USGS) - The Federal agency responsible for nationwide civilian mapping projects and standards development. UTM Grid - The Universal Transverse Mercator grid, a system of plane coordinates based upon 60 north-south trending zones, each 6 degrees of longitude wide, that circle the globe. Vector Data - Coordinate-based data used to represent linear geographic features. Each linear feature is represented as an ordered list of vertices. GLOSSARY OF ACRONYMS AML ARC Macro Language ASCII American Standard Code of Information Interchange BFE Base Flood Elevation CBRS Coastal Barrier Resources System CCITT Conseil Consultif Internationale de Telegraphique et Telephonique (International Consultive Committee for Telegraphy and Telephony) CD ROM Compact Disk Read-Only Memory CID Community Identification CRS Community Rating System DFIRM Digital Flood Insurance Rate Map DFIRM-DLG Digital Flood Insurance Rate Map - Digital Line Graph DLG Digital Line Graph DOS Disk Operating System ERM Elevation Reference Mark FEMA Federal Emergency Management Agency FGDC Federal Geographic Data Committee FIA Federal Insurance Administration FIPS Federal Information Processing Standards FIRM Flood Insurance Rate Map FIRM-DLG Flood Insurance Rate Map - Digital Line Graph GIS Geographic Information System LOMA Letter of Map Amendment LOMC Letter of Map Change LOMR Letter of Map Revision NFIP National Flood Insurance Program Q3 Quality Level 3 QA/QC Quality Assurance/Quality Control SBA Small Business Administration SDTS Spatial Data Transfer Standards SFHA Special Flood Hazard Area TIFF Tagged Image File Format TIGER Topologically Integrated Geographic Encoding and Referencing USGS United States Geological Survey UTM Universal Transverse Mercator REFERENCES REFERENCES 1. Federal Emergency Management Agency, FIA-21, Standards for Digital Flood Insurance Rate Maps, October 1993, Federal Emergency Management Agency, Washington, D.C. 2. Federal Emergency Management Agency, Community Status Book, updated regularly, Federal Emergency Management Agency, Washington, D.C. 3. Federal Emergency Management Agency, FIA-15, National Flood Insurance Program Community Rating System Coordinator's Manual, August 31, 1993, Federal Emergency Management Agency, Washington, D.C. 4. Federal Emergency Management Agency, Publication 186, Mandatory Purchase of Flood Insurance Guidelines, October 1989, Federal Emergency Management Agency, Washington, D.C. 5. Federal Emergency Management Agency, Q3 Flood Data Users Guide, Draft March 1996, Federal Emergency Management Agency, Washington, D.C. 6. Environmental Systems Research Institute, Inc., Using Map Libraries: Spatial Management and Librarian Command References, Environmental Systems Research Institute, Inc., Redlands, California. 7. National Institute of Standards and Technology, Publication 6-4, Federal Information Processing Standard 6-4, August 31, 1990, National Institute of Standards and Technology, Gaithersburg, Maryland. 8. U.S. Geological Survey, State Indexes to Topographic and Other Map Coverage, U.S. Geological Survey, Reston, Virginia. 9. U.S. Geological Survey, Standards for Digital Line Graphs, U.S. Geological Survey, Reston, Virginia. 10. Federal Geographic Data Committee, Content Standards for Digital Geospatial Metadata, June 8, 1994, Federal Geographic Data Committee, Washington, D.C.