Guidelines & Specifications for Flood Hazard Mapping Partners [April 2003] 

Appendix L
Guidance for Preparing Draft Digital Data and DFIRM Database

The following Summary of Changes details revisions of Appendix L subsequent to the initial publication of 
the Guidelines in February 2002. These changes represent new or updated guidance for Flood Hazard 
Mapping Partners. 

Date Affected 
Section(s) 
Summary of Change 
April 2003 Purpose Clarified that the FEMA Lead assigns tasks to the Mapping 
Partner(s). 
April 2003 L.1 Corrected typographic errors. 
April 2003 L.1 Expanded the description of the Standard and Enhanced 
DFIRM Databases. 
April 2003 L.1 Rearranged table L-1 alphabetically. 
April 2003 L.1 Removed L_Riv_Model from t able L-1. 
April 2003 L.1 Removed duplicate L_Stn_Start from table L-1. 
April 2003 L.1 Added the Enhanced DFIRM Database tables to table L-1. 
April 2003 L.1 Removed L_Cst_Model from table L-2. 
April 2003 L.1 Removed L_Riv_Model from table L-2. 
April 2003 L.1 Added the Enhanced DFIRM Database tables to table L-2. 
April 2003 L.1 Added a discussion on Database Design Decisions. 
April 2003 L.1.2 Expanded the discussion on what option Mapping Partners 
should follow for their submission. 
April 2003 L.1.2 Corrected section cross -references. 
April 2003 L.1.2 
Clarified that Mapping Partners submitting Draft digital 
data may use either Preliminary and Final DFIRM Data 
structure or Draft Digital Data structure. 
April 2003 L.1.2 Corrected typographic errors. 
April 2003 L.2.1 Corrected typographic error. 
April 2003 L.2.1 Clarified that the Appendix provides a standard schema. 
April 2003 L.2.4 Corrected typographic error. 
April 2003 L.2.4 Clarified the requirements for the studys projection. 
April 2003 L.2.5 Clarified that the arrangements are made with the FEMA 
Lead. 
April 2003 L.2.5.3 Corrected typographic error. 
April 2003 L.2.5.3 Corrected formatting error. 
April 2003 L.2.5.8 Added PLSS tables to base map tables that need not follow 
the DFIRM structure if existing data is used. 


April 2003 L.2.5.8 Corrected typographic error. 
April 2003 L.2.5.8 Modified discussion to explain the relationship between the 
base map to the flood hazard data. 
April 2003 L.2.5.8 Removed the flood hazard data tables from Table L-5. 
April 2003 L.2.5.9 
Clarified that attribute tables are required to have a primary 
key that matches the spatial data table only when attribute 
data and spatial data are stored in separate files such as 
with a CADD data format or when attributes for GIS data 
are stored in a separate RDBMS. 
April 2003 L.2.5.9 Corrected section cross -references. 
April 2003 L.2.5.10 Added a discussion on Standard and Enhanced required 
components. 
April 2003 L.2.5.10 Described the Standard/Enhanced code used L.4 and L.7. 
April 2003 L.2.5.10 
Enhanced discussion of Null values for various data types. 
Added discussion of Not Populated values for situations 
where data does not follow requirements of specification. 
April 2003 L.2.5.10 Added discussion of true/false fields in the DFIRM 
database. 
April 2003 L.2.5.10 Corrected typographic errors. 
April 2003 L.2.6 Corrected section cross -references. 
April 2003 L.2.6 Corrected typographic error. 
April 2003 L.2.7 Clarified that metadata file is provided in ASCII text 
format. 
April 2003 L.2.7.2 Corrected section cross -references. 
April 2003 L.2.7.2 Corrected typographic error. 
April 2003 L.2.7.2 Added SID and PNG as acceptable raster formats. 
April 2003 L.2.7.2 Changed references to orthophotos to the less restrictive 
description of raster base maps. 
April 2003 L.2.7.2 Modified the data directory structure. 
April 2003 L.2.8 Corrected typographic error. 
April 2003 L.2.8 Corrected structure of metdata file name. 
April 2003 L.3.2.1 Corrected typographic error. 
April 2003 L.3.2.1 Corrected section cross -references. 
April 2003 L.3.5 Corrected section cross -references. 
April 2003 L.3.5.1 Clarified discussion of Tiling. 
April 2003 L.3.5.2 Clarified discussion of nodes and vertices for Topology. 
April 2003 L.3.5.3 Corrected section cross -references. 
April 2003 L.3.5.4 Corrected section cross -references. 
April 2003 L.3.5.5 Corrected section cross -references. 
April 2003 L.3.5.6 Clarified that issues will be resolved the the FEMA Lead. 
April 2003 L.3.5.7 Corrected sectio n cross -references. 
April 2003 L.3.5.8 
Added PLSS tables to base map tables that need not follow 
the DFIRM structure if existing data is used. Clarified the 
tables to which this exception applies. 
April 2003 L.3.5.8 Modified discussion to explain the relationship between the 
base map to the flood hazard data. 
April 2003 L.3.5.8 Removed the flood hazard data tables from Table L-7. 
April 2003 L.3.5.11 Added a discussion on Standard and Enhanced required 


components. 
April 2003 L.3.5.11 Described the Standard/Enhanced code used L.4 and L.7. 
April 2003 L.3.5.11 
Enhanced discussion of Null values for various data types. 
Added discussion of Not Populated values for situations 
where data does not follow requirements of specification. 
April 2003 L.3.5.11 Corrected typographic error. 
April 2003 L.3.5.11 Added discussion of true/false fields in the DFIRM 
database. 
April 2003 L.3.7 Clarified that the Mapping Partner should submit the 
FEMA Mapping Information Checklist. 
April 2003 L.3.7 Clarified that the FIS text should be in PDF format with 
appropriate bookmarks. 
April 2003 L.3.7.2 Corrected typographic error. 
April 2003 L.3.7.2 Changed references to orthophotos to the less restrictive 
description of raster base maps. 
April 2003 L.3.7.2 Corrected reference to format of preliminary data files for 
QA/QC. 
April 2003 L.3.7.2 Modified the data directory structure. 
April 2003 L.3.8 Corrected typographic error. 
April 2003 L.3.8 Corrected structure of metdata file name. 
April 2003 
L.4 
S_BFE 
Corrected typogra phic error. 
April 2003 
L.4 
S_BFE 
Renamed UNITS_LID field to LEN_LID. 
April 2003 
L.4 
S_CBRS 
Changed CBRS_LID and CBRS_DATE to required if 
applicable instead of required. 
April 2003 
L.4 
S_CBRS 
Expanded description of the CBRS_TF field. 
April 2003 
L.4 
S_CBRS 
Clarified description of the S_CBRS table. 
April 2003 
L.4 
S_CBRS 
Clarified description of the CBRS_DATE field. 
April 2003 
L.4 
S_Cst_Gage 
Added the S_Cst_Gage table. 
April 2003 
L.4 
S_Cst_Tsct_Ln 
Removed CST_MDL_ID. 
April 2003 
L.4 
S_Cst_Tsct_Ln 
Added Enhanced attributes. 
April 2003 
L.4 
S_DOQ_Index 
Renamed the S_DOQ_Index table to S_Base_Index. 
April 2003 
L.4 
S_DOQ_Index 
Renamed DOQ_ID field to BASE_ID. 
April 2003 
L.4 
S_DOQ_Index 
Renamed DOQ_DATE field to BASE_DATE. 
April 2003 
L.4 
S_DOQ_Index 
Changed references to orthophotos to the less restrictive 
description of raster base maps. 
April 2003 
L.4 
S_FIRM_Pan 
Changed the requirement for panels that extend past the 
administrative boundaries of the area mapped to extend out 


to the mapped panel neatlines rather than be clipped to the 
boundary of the area mapped. 
April 2003 
L.4 
S_FIRM_Pan 
Changed capitalization of PNP_REASON. 
April 2003 
L.4 
S_Fld_Haz_Ar 
Expanded description of SFHA_TF field. 
April 2003 
L.4 
S_Fld_Haz_Ar 
Clarified that the units field applies to depths as well as 
BFEs. 
April 2003 
L.4 
S_Fld_Haz_Ar 
Added a DEP_REVERT field to hold a depth value for AR 
zones that required depths for the reverted zone. 
April 2003 
L.4 
S_Fld_Haz_Ar 
Expanded discussion of SOURCE_CIT to say that the 
flood zones will be divided to track the sources of the most 
recent revision, but not previous revisions. 
April 2003 
L.4 
S_Fld_Haz_Ar 
Renamed UNIT_LID field to LEN_LID. 
April 2003 
L.4 
S_Fld_Haz_Ar 
Renamed VEL_UNITS field to VEL_LID. 
April 2003 
L.4 
S_Fld_Haz_Ar 
Added Enhanced attributes. 
April 2003 
L.4 
S_Fld_Haz_Ln 
Removed the SOURCE_CIT field. 
April 2003 
L.4 
S_Gen_Struct 
Changed the field WTR_NM to WTR_LID. 
April 2003 
L.4 
S_Label_Ld 
Corrected typographic error. 
April 2003 
L.4 
S_Label_Pt 
Expanded description of DEGREES field. 
April 2003 
L.4 
S_LOMR 
Clarified that the polygon is the outline shown on the 
LOMR attachment. 
April 2003 
L.4 
S_LOMR 
Added Enhanced attributes. 
April 2003 
L.4 
S_Nodes 
Added the S_Nodes table. 
April 2003 
L.4 
S_Ovrbnkln 
Added the S_Ovrbnkln table. 
April 2003 
L.4 
S_Perm_Bmk 
Corrected typographic error. 
April 2003 
L.4 
S_PFD_Ln 
Added the S_PFD_Ln table. 
April 2003 
L.4 
S_PLSS_Ar 
Corrected typographic error. 
April 2003 
L.4 
S_PLSS_Ln 
Changed the requirements for PLSS data to be analogous to 
Transportation and Water features. Existing data used for a 
DFIRM is not required to be restructured to follow the 
DFIRM database specification. The table is not required if 
the data used for the hard copy map is not available for free 
public distribution by FEMA. 
April 2003 L.4 Fixed confusion between the COMM_NO and the CID 


S_Pol_Ar fields. The CID field is the concatenation of the two -digit 
state FIPs code and COMM_NO. 
April 2003 
L.4 
S_Pol_Ar 
Added text values to use for COMM_NO when local 
jurisdiction does not apply to an area. 
April 2003 
L.4 
S_Pol_Ar 
Fixed capitalization of POL_NAME1 and POL_NAME2. 
April 2003 
L.4 
S_Pol_Ar 
Expanded description of ANI_TF field. 
April 2003 
L.4 
S_Pol_Ar 
Removed SOURCE_CIT field. 
April 2003 
L.4 
S_Pol_Ar 
Corrected typographic error. 
April 2003 
L.4 
S_Precip_Gage 
Added the S_Precip_Gage table. 
April 2003 
L.4 
S_Profil_Basln 
Added the S_Profil_Basln table. 
April 2003 
L.4 
S_Quad 
Renamed table S_Quad to S_Quad_Index. 
April 2003 
L.4 
S_Shore_Ln 
Added the S_Shore_Ln table . 
April 2003 
L.4 
S_Stn_Start 
Added the S_Stn_Start table. 
April 2003 
L.4 
S_Subbasins 
Added the S_Subbasins table. 
April 2003 
L.4 
S_Trnsport_Ln 
Changed NM_TYP field to NM_LID. 
April 2003 
L.4 
S_Trnsport_Ln 
Changed references to orthophotos to the less restrictive 
description of raster base maps. 
April 2003 
L.4 
S_Trnsport_Ln 
Clarified that FEAT_NM1 should also be used for route 
numbers and Intercoastal Waterway. 
April 2003 
L.4 
S_Water_Gage 
Added the S_Water_Gage. 
April 2003 
L.4 
S_Wtr_Ar 
Changed references to orthophotos to the less restrictive 
description of raster base maps. 
April 2003 
L.4 
S_Wtr_Ar 
Changed reference to table name D_Wtr_Typ to 
D_Water_Typ. 
April 2003 
L.4 
S_Wtr_Ln 
Changed references to orthophotos to the less restrictive 
description of raster base maps. 
April 2003 
L.4 
S_Wtr_Ln 
Changed reference to table name D_Wtr_Typ to 
D_Water_Typ. 
April 2003 
L.4 
S_XS 
Added fields for vertical datum and units that apply to the 
WSEL_100 field. 
April 2003 
L.4 
S_XS 
Removed field XS_NO. 
April 2003 
L.4 
S_XS 
Renamed WSEL_100 field to WSEL_REG. 
April 2003 L.4 Renamed UNITS_LID field to LEN_LID. 


S_XS 
April 2003 
L.4 
S_XS 
Corrected typographic error by renaming V_DATUM_LID 
field to V_DATM_LID. 
April 2003 
L.4 
S_XS 
Removed the RIV_MDL_ID field. 
April 2003 
L.4 
S_XS 
Fixed formatting error. 
April 2003 
L.4 
S_XS 
Clarified that XS_LTR can be either a letter or a number. 
April 2003 
L.4 
S_XS 
Added Enhanced attributes. 
April 2003 
L.4 
Study_Info 
Changed the STUDY_PRE field and JURIS_TYP field to 
required if applicable rather than required. 
April 2003 
L.4 
Study_Info 
Expanded description of OPP_TF field. 
April 2003 
L.4 
Study_Info 
Expanded description of CW_TF field. 
April 2003 
L.4 
Study_Info 
Expanded description of RTROFT_TF field. 
April 2003 
L.4 
Study_Info 
Added META_NM field. 
April 2003 
L.4 
Study_Info 
Removed UNIT_LID from matrix. 
April 2003 
L.4 
Study_Info 
Added Enhanced attributes. 
April 2003 
L.4 
L_Aux_Data 
Added the S_Aux_Data table. 
April 2003 
L.4 
L_Case_Info 
Added the S_Case_Info table. 
April 2003 
L.4 
L_Comm_Info 
Clarified that all communities within the area of study are 
included in the table. 
April 2003 
L.4 
L_Comm_Info 
Changed REPOS_ADR2 to required if applicable rather 
than required. 
April 2003 
L.4 
L_Comm_Info 
Expanded description of REPOS_ST . 
April 2003 
L.4 
L_Comm_Info 
Expanded description of IN_ID_DAT field. 
April 2003 
L.4 
L_Comm_Info 
Expanded description of IN_NFIP_DT field. 
April 2003 
L.4 
L_Comm_Info 
Expanded description of IN_FRM_DAT field. 
April 2003 
L.4 
L_Comm_Info 
Expanded description of IN_RECENT_DAT field. 
April 2003 
L.4 
L_Cst_Model 
Removed from Standard. Existing attributes and additional 
attributes were added as part of the Enhanced. 
April 2003 
L.4 
L_Hydra_Model 
Added the L_Hydra_Model table. 


April 2003 
L.4 
L_Hydro_Model 
Added the L_Hydro_Model table. 
April 2003 
L.4 
L_Media 
Added the L_Media table. 
April 2003 
L.4 
L_MT1_LOMC 
Added a value of redetermined for LOMCs included in 
Draft Digital Data submissions. 
April 2003 
L.4 
L_MT1_LOMC 
Changed the description of the FIRM_PAN field so that it 
is not described as a foreign key. 
April 2003 
L.4 
L_Node_Disch 
Added the L_Node_Disch table. 
April 2003 
L.4 
L_Pan_Revis 
Added REVIS_ID field as primary key. 
April 2003 
L.4 
L_Pan_Revis 
Changed description of FIRM_PAN field so that it is not 
described as a primary key. 
April 2003 
L.4 
L_Pol_FHBM 
Changed the name of the COMM_NO field to CID to 
remain consistent with the S_Pol_Ar table. 
April 2003 
L.4 
L_Pol_FHBM 
Added FHBM_ID as a primary key. 
April 2003 
L.4 
L_Pol_FHBM 
Changed description of CID so that it is not described as a 
primary key. 
April 2003 
L.4 
L_Regression 
Added the L_Regression table. 
April 2003 
L.4 
L_Riv_Model 
Removed the L_Riv_Model table. 
April 2003 
L.4 
L_Stn_Start 
Clarified that multiple reaches can share the same entry . 
April 2003 
L.4 
L_Stn_Start 
Added a requirement to include units of measure in the 
start description. 
April 2003 
L.4 
L_Stn_Start 
Removed the SOURCE_CIT field. 
April 2003 
L.4 
L_Storm_Curve 
Added the L_Storm_Curve table. 
April 2003 
L.4 
L_Storm_Info 
Added the L_Storm_Info table. 
April 2003 
L.4 
L_Subbas_Disch 
Added the L_Subbas_Disch table. 
April 2003 
L.4 
L_Wtr_Nm 
Removed L_Cst_Model table and L_Riv_Model table from 
WTR_NM_LID fields description. 
April 2003 
L.4 
L_XS_Ratings 
Added the L_XS_Ratings table . 
April 2003 L.4 
Replaced the previous chart showing table structure in 
Microsoft Access with detailed table structure for 
Microsoft Access, ESRI Shapefile, ESRI Coverage and 
MapInfo table formats for all tables. 
April 2003 L.4 
Removed acceptable domain values from this section and 
replaced them with detailed table structure for Microsoft 
Access, ESRI Shapefile, ESRI Coverage and MapInfo table 
formats. Added a new Section L.9 listing acceptable 


values for all standardized domains. 
April 2003 L.4 Some domain tables had additional values added and 
typographic corrections made. 
April 2003 
L.4 
D_Area_Units 
Added the D_Area_Units table. 
April 2003 
L.4 
D_CBRS_Typ 
Corrected typographic error. 
April 2003 
L.4 
D_Discharge_Units 
Added the D_Discharge_Units table. 
April 2003 
L.4 
D_Eros_Method 
Added the D_Eros_Method table. 
April 2003 
L.4 
D_Frequency 
Added the D_Frequency table. 
April 2003 
L.4 
D_Gage 
Added the D_Gage table. 
April 2003 
L.4 
D_Label_Typ 
Corrected typographic error. 
April 2003 
L.4 
D_Ln_Typ 
Corrected typographic error. 
April 2003 
L.4 
D_Ln_Typ 
Capitalized pct in LN_TYP field description and domain 
values. 
April 2003 
L.4 
D_Ln_Typ 
Added a discussion regarding the lines for SFHA 
boundaries. 
April 2003 
L.4 
D_Ln_Typ 
Added line type MEANDER to precedence for PLSS data. 
April 2003 
L.4 
D_Method 
Added the D_Method table. 
April 2003 
L.4 
D_Nodes 
Added the D_Nodes table. 
April 2003 
L.4 
D_Runup_Mdl 
Added the D_Runup_Mdl table. 
April 2003 
L.4 
D_Shr_Rough 
Added the D_Shr_Rough table. 
April 2003 
L.4 
D_Shr_Typ 
Added the D_Shr_Typ table. 
April 2003 
L.4 
D_Storms 
Added the D_Storms table. 
April 2003 
L.4 
D_Surge_Mdl 
Added the D_Surge_Mdl table. 
April 2003 
L.4 
D_Time_Units 
Added the D_Time_Units table. 
April 2003 
L.4 
D_Trans_Typ 
Added dis cussion on when the value undefined should be 
used. 
April 2003 
L.4 
D_Units 
Replaced with D_Length_Units. 
April 2003 
L.4 
D_Velocity_Units 
Added the D_Velocity_Units table. 


April 2003 
L.4 
D_Volume_Units 
Added the D_Volume_Units table. 
April 2003 
L.4 
D_VZone 
Added the D_VZone table. 
April 2003 
L.4 
D_Water_Typ 
Increased the width of the WATER_TYP field. 
April 2003 
L.4 
D_Wave_Mdl 
Added the D_Wave_Mdl table. 
April 2003 
L.4 
D_Zone 
Corrected typographic errors. 
April 2003 
L.4 
D_Zone 
Capitalized pct in FLD_ZONE field description and 
domain values. 
April 2003 L.5 Corrected typographic error. 
April 2003 L.5 Added SID and PNG to list of raster data formats. 
April 2003 L.6 Modified the metadata to be processed by mp with fewer 
errors. 
April 2003 L.6 Removed Right of ways as a format for road data. 
April 2003 L.6 Removed L_Riv_Model from the tables in the data set. 
April 2003 L.6 Changed metadata file name. 
April 2003 L.6 Added indents to clarify data structure relative to FGDC 
metadata standards. 
April 2003 
L.7 
S_Base_Index 
Corrected typographic error. 
April 2003 
L.7 
S_BFE 
Renamed UNITS field to LEN_UNIT. 
April 2003 
L.7 
S_BFE 
Corrected typographic error. 
April 2003 
L.7 
S_CBRS 
Changed CBRS_TYP and CBRS_DATE to required if 
applicable instead of required. 
April 2003 
L.7 
S_CBRS 
Expanded description of the CBRS_TF field. 
April 2003 
L.7 
S_CBRS 
Clarified description of the S_CBRS table. 
April 2003 
L.7 
S_CBRS 
Clarified description of the CBRS_DATE field. 
April 2003 
L.4 
S_Cst_Gage 
Added the S_ Cst_Gage table. 
April 2003 
L.7 
S_Cst_Tsct_Ln 
Removed CST_MDL_ID field. 
April 2003 
L.7 
S_Cst_Tsct_Ln 
Added Enhanced attributes. 
April 2003 
L.7 
S_DOQ_Index 
Renamed the S_DOQ_Index table to S_Base_Index. 
April 2003 
L.7 
S_DOQ_Index 
Renamed DOQ_ID field t o BASE_ID. 
April 2003 
L.7 
S_DOQ_Index 
Renamed DOQ_DATE field to BASE_DATE. 


April 2003 
L.7 
S_DOQ_Index 
Changed references to orthophotos to the less restrictive 
description of raster base maps. 
April 2003 
L.7 
S_FIRM_Pan 
Changed the requirement for panels that extend past the 
administrative boundaries of the area mapped to extend out 
to the mapped panel neatlines rather than be clipped to the 
boundary of the area mapped. 
April 2003 
L.7 
S_FIRM_Pan 
Changed capitalization of PNP_REASON. 
April 2003 
L.7 
S_Fld_Haz_Ar 
Corrected typographic error. 
April 2003 
L.7 
S_Fld_Haz_Ar 
Capitalized pct in FLD_ZONE field description. 
April 2003 
L.7 
S_Fld_Haz_Ar 
Expanded description of SFHA_TF field. 
April 2003 
L.7 
S_Fld_Haz_Ar 
Renamed UNITS field to LEN_UNIT. 
April 2003 
L. 7 
S_Fld_Haz_Ar 
Clarified that the units field applies to depths as well as 
BFEs. 
April 2003 
L.7 
S_Fld_Haz_Ar 
Renamed VEL_UNITS to VEL_UNIT. 
April 2003 
L.7 
S_Fld_Haz_Ar 
Added a DEP_REVERT field to hold a depth value for AR 
zones that required depths for the reverted zone. 
April 2003 
L.7 
S_Fld_Haz_Ar 
Expanded discussion of SOURCE_CIT to say that the 
flood zones will be divided to track the sources of the most 
recent revision, but not previous revisions. 
April 2003 
L.7 
S_Fld_Haz_Ar 
Added Enhanced attributes. 
April 2003 
L.7 
S_Fld_Haz_Ln 
Corrected typographic error. 
April 2003 
L.7 
S_Fld_Haz_Ln 
Removed the SOURCE_CIT field. 
April 2003 
L.7 
S_Label_Ld 
Corrected typographic error. 
April 2003 
L.7 
S_Label_Pt 
Expanded description of DEGREES field. 
April 2003 
L.7 
S_LOMR 
Clarified that the polygon is the outline shown on the 
LOMR attachment. 
April 2003 
L.7 
S_LOMR 
Added Enhanced attributes. 
April 2003 
L.7 
S_Nodes 
Added the S_Nodes table. 
April 2003 
L.7 
S_Ovrbnkln 
Added the S_Ovrbnkln table. 
April 2003 
L.7 
S_Perm_Bmk 
Corrected typographic error. 
April 2003 
L.7 
S_PFD_Ln 
Added the S_PFD_Ln table. 


April 2003 
L.7 
S_PLSS_Ar 
Changed the requirements for PLSS data to be analogous to 
Transportation and Water features. Existing data used for a 
DFIRM is not required to be restructured to follow the 
DFIRM database specification. The table is not required if 
the data used for the hard copy map is not available for free 
public distribution by FEMA. 
April 2003 
L.7 
S_PLSS_Ar 
Corrected typographic errors. 
April 2003 
L.7 
S_PLSS_Ln 
Changed the requirements for PLSS data to be analogous to 
Transportation and Water features. Existing data used for a 
DFIRM is not required to be restructured to follow the 
DFIRM database specification. The table is not required if 
the data used for the hard copy map is not available for free 
public distribution by FEMA. 
April 2003 
L.7 
S_PLSS_Ln 
Corrected typographic errors. 
April 2003 
L.7 
S_Pol_Ar 
Fixed confusion between the COMM_NO and the CID 
fields. The CID field is the concatenation of the two digit 
state FIPs code and COMM_NO. 
April 2003 
L.7 
S_Pol_Ar 
Added text values to use for COMM_NO when local 
jurisdiction does not apply to an area. 
April 2003 
L.7 
S_Pol_Ar 
Fixed capitalization of POL_NAME1 and POL_NAME2. 
April 2003 
L.7 
S_Pol_Ar 
Expanded description of ANI_TF field. 
April 2003 
L.7 
S_Pol_Ar 
Removed SOU RCE_CIT field. 
April 2003 
L.7 
S_Pol_Ar 
Corrected typographic error. 
April 2003 
L.7 
S_Precip_Gage 
Added the S_Precip_Gage table. 
April 2003 
L.7 
S_Profil_Basln 
Added the S_Profil_Basln table. 
April 2003 
L.7 
S_Quad 
Renamed table S_Quad to S_Quad_Index. 
April 2003 
L.7 
S_Shore_Ln 
Added the S_Shore_Ln table. 
April 2003 
L.7 
S_Stn_Start 
Added the S_Stn_Start table. 
April 2003 
L.7 
S_Subbasins 
Added the S_Subbasins table. 
April 2003 
L.7 
S_Trnsport_Ln 
Changed references to orthophotos to the less restrictive 
description of raster b ase maps. 
April 2003 
L.7 
S_Trnsport_Ln 
Clarified that FEAT_NM1 should also be used for route 
numbers and Intercoastal Waterway. 
April 2003 
L.7 
S_Trnsport_Ln 
Corrected typographic error. 
April 2003 
L.7 
S_Water_Gage 
Added the S_Water_Gage table. 


April 2003 
L.7 
S_Wtr_Ar 
Increased the width of the WATER_TYP field. 
April 2003 
L.7 
S_Wtr_Ar 
Changed references to orthophotos to the less restrictive 
description of raster base maps. 
April 2003 
L.7 
S_Wtr_Ar 
Changed reference to table name D_Wtr_Typ to 
D_Water_Typ. 
April 2003 
L.7 
S_Wtr_Ln 
Increased the width of the WATER_TYP field. 
April 2003 
L.7 
S_Wtr_Ln 
Changed references to orthophotos to the less restrictive 
description of raster base maps. 
April 2003 
L.7 
S_Wtr_Ln 
Changed reference to table name D_Wtr_Typ to 
D_Water_Typ. 
April 2003 
L.7 
S_XS 
Added fields for vertical datum and units that apply to the 
WSEL_100 field. 
April 2003 
L.7 
S_XS 
Removed field XS_NO. 
April 2003 
L.7 
S_XS 
Renamed WSEL_100 field to WSEL_REG. 
April 2003 
L.7 
S_XS 
Renamed UNITS field to LEN_UNIT. 
April 2003 
L.7 
S_XS 
Removed the RIV_MDL_ID field. 
April 2003 
L.7 
S_XS 
Fixed formatting error. 
April 2003 
L.7 
S_XS 
Clarified that XS_LTR can be either a letter or a number. 
April 2003 
L.7 
S_XS 
Added Enhanced attributes. 
April 2003 
L.7 
Study_Info 
Changed the STUDY_PRE field and JURIS_TYP field to 
required if applicable rather than required. 
April 2003 
L.7 
Study_Info 
Expanded description of OPP_TF field. 
April 2003 
L.7 
Study_Info 
Expanded description of CW_TF field. 
April 2003 
L.7 
Study_Info 
Expanded description of RTROFT_TF field. 
April 2003 
L.7 
Study_In fo 
Added META_NM field. 
April 2003 
L.7 
Study_Info 
Removed UNITS from the matrix. 
April 2003 
L.7 
Study_Info 
Added Enhanced attributes. 
April 2003 
L.7 
L_Aux_Data 
Added the L_Aux_Data table. 
April 2003 
L.7 
L_Case_Info 
Added the L_Case_Info table. 
April 2003 L.7 Removed from Standard. Existing attributes and additional 


L_Cst_Model attributes were added as part of the Enhanced. 
April 2003 
L.7 
L_Comm_Info 
Clarified that all communities within the area of study are 
included in the table. 
April 2003 
L.7 
L_Comm_Info 
Changed REPOS_ADR2 to required if applicable rather 
than required. 
April 2003 
L.7 
L_Comm_Info 
Expanded description of REPOS_ST. 
April 2003 
L.7 
L_Comm_Info 
Expanded description of IN_ID_DAT field. 
April 2003 
L.7 
L_Comm_Info 
Expanded description of IN_NFIP_DT field. 
April 2003 
L.7 
L_Comm_Info 
Expanded description of IN_FRM_DAT field. 
April 2003 
L.7 
L_Comm_Info 
Expanded description of IN_RECENT_DAT field. 
April 2003 
L.7 
L_Hydra_Model 
Added the L_Hydra_Model table. 
April 2003 
L.7 
L_Hydro_Model 
Added the L_Hydro_Model table. 
April 2003 
L.7 
L_Media 
Added the L_Media table. 
April 2003 
L.7 
L_MT1_LOMC 
Added a value of redetermined for LOMCs included in 
Draft Digital Data submissions. 
April 2003 
L.7 
L_MT1_LOMC 
Changed the description of the FIRM_PAN field so that it 
is not described as a foreign key. 
April 2003 
L.7 
L_Node_Disch 
Added the L_Node_Disch table. 
April 2003 
L.7 
L_Pan_Revis 
Added REVIS_ID field as primary key. 
April 2003 
L.7 
L_Pan_Revis 
Changed description of FIRM_PAN field so that it is not 
described as a primary key. 
April 2003 
L.7 
L_Pol_FHBM 
Changed the name of the COMM_NO field to CID to 
remain consistent with the S_Pol_Ar table. 
April 2003 
L.7 
L_Pol_FHBM 
Added FHBM_ID as a primary key. 
April 2003 
L.7 
L_Pol_FHBM 
Changed description of CID so that it is not described as a 
primary key. 
April 2003 
L.7 
L_Regression 
Added the L_Regression table. 
April 2003 
L.7 
L_Riv_Model 
Removed the L_Riv_Model table. 
April 2003 
L.7 
L_Stn_Start 
Clarified that multiple reaches can share the same entry. 
April 2003 
L.7 
L_Stn_Start 
Added a requirement to include units of measure in the 
start description. 
April 2003 
L.7 
L_Stn_Start 
Removed the SOURCE_CIT field. 


April 2003 
L.7 
L_Storm_Curve 
Added the L_Storm_Curve table. 
April 2003 
L.7 
L_Storm_Info 
Added the L_Storm_Info table. 
April 2003 
L.7 
L_Subbas_Disch 
Added the L_Subbas_Disch table. 
April 2003 
L.7 
L_XS_Ratings 
Added the L_XS_Ratings table. 
April 2003 L.7 
Replaced the previous chart showing table structure in 
Microsoft Access with detailed table structure for 
Microsoft Access, ESRI Shapefile, ESRI Coverage and 
MapInfo table formats for all tables. 
April 2003 L.8 Modified the metadata to be processed by mp with fewer 
errors. 
April 2003 L.8 Removed L_Riv_Model from the tables in the data set. 
April 2003 L.8 Changed metadata file name. 
April 2003 L.8 Added indents to clarify data structure relative to FGDC 
metadata standards. 
April 2003 L.9 Added a new section, Section L.9, listing acceptable values 
for all standardized domains. 
April 2003 L.9 Some domain tables had additional values added and 
typographic corrections made. 
April 2003 L.9 Domain tables for the Enhanced attributes were added. 


Summary of Changes............................................................................................................i

L.1 Digital Flood Insurance Rate Map Database Overview......................................... 16

Database Design Decisions ....................................................................................... 22

L.1.1 Spatial Data and Tabular Data .................................................................. 22

L.1.2 Draft Digital Data Versus Preliminary and Final Digital Flood Insurance 
Rate Map Databases.................................................................................................. 23

L.2 Preparation of Draft Digital Data ........................................................................... 24

L.2.1 General...................................................................................................... 24

L.2.2 Coordination.............................................................................................. 25

L.2.2.1 Data Sources ......................................................................................... 26

L.2.3 Standards ................................................................................................... 27

L.2.4 Horizontal and Vertical Control................................................................ 27

L.2.5 Digital Data Structure ............................................................................... 28

L.2.5.1 Tiling ..................................................................................................... 28
L.2.5.2 Topology ............................................................................................... 28
L.2.5.3 Edgematching........................................................................................ 29
L.2.5.4 Coincident Features............................................................................... 30
L.2.5.5 Precise Features..................................................................................... 31
L.2.5.6 Data Compilation.................................................................................. 31
L.2.5.7 Digitizing .............................................................................................. 31
L.2.5.8 Relationship of Base Map to Flood Hazard Data ................................. 32
L.2.5.9 Computer Assisted Drafting and Design or Geographic Information
System Preparation................................................................................................. 33
L.2.5.10 Table Structure ...................................................................................... 33
L.2.5.11 Spatial Files for Computer Assisted Drafting and Design Format ....... 36

L.2.6 Quality Control ......................................................................................... 40

L.2.7 Deliverables .............................................................................................. 40

L.2.7.1 Hardcopy Deliverables.......................................................................... 41
L.2.7.2 Digital Deliverables .............................................................................. 41

L.2.8 Metadata.................................................................................................... 44

L.3 Preparation of Preliminary and Final Digital Flood Insurance Rate Map
Databases .......................................................................................................................... 45

L.3.1 General...................................................................................................... 45


L.3.2 Coordination.............................................................................................. 45
L.3.2.1 Data Sources ......................................................................................... 45
L.3.3 Standards ................................................................................................... 46

L.3.4 Horizontal and Vertical Control................................................................ 46

L.3.5 Data Structure ........................................................................................... 47

L.3.5.1 Tiling ..................................................................................................... 47
L.3.5.2 Topology ............................................................................................... 47
L.3.5.3 Edgematching........................................................................................ 48
L.3.5.4 Coincident Features............................................................................... 48
L.3.5.5 Precise Features..................................................................................... 48
L.3.5.6 Data Compilation.................................................................................. 48
L.3.5.7 Digitizing .............................................................................................. 49
L.3.5.8 Relationship of Base Map to Flood Hazard Data ................................. 49
L.3.5.9 Computer Assisted Drafting and Design or Geographic Information
System Preparation................................................................................................. 50
L.3.5.10 Table Structure ...................................................................................... 50
L.3.5.11 Spatial Files........................................................................................... 50

L.3.6 Quality Control ......................................................................................... 52

L.3.7 Deliverables .............................................................................................. 52

L.3.7.1 Hardcopy Deliverables.......................................................................... 52
L.3.7.2 Digital Deliverables .............................................................................. 52

L.3.8 Metadata.................................................................................................... 54
L.4 Database Table Structure Requirements for Draft Digital Data............................. 56

Table: S_Base_Index.................................................................................... 56

Table: S_Base_Index.................................................................................... 57
Table: S_BFE ............................................................................................... 58
Table: S_BFE ............................................................................................... 59

Table: S_CBRS ............................................................................................ 60
Table: S_CBRS ............................................................................................ 61

Table: S_Cst_Gage ....................................................................................... 62
Table: S_Cst_Gage ....................................................................................... 64
Table: S_Cst_Tsct_Ln.................................................................................. 65


Table: S_Cst_Tsct_Ln.................................................................................. 69
Table: S_FIRM_Pan..................................................................................... 72
Table: S_FIRM_Pan..................................................................................... 75
Table: S_Fld_Haz_Ar .................................................................................. 77
Table: S_Fld_Haz_Ar .................................................................................. 80
Table: S_Fld_Haz_Ln .................................................................................. 82
Table: S_Fld_Haz_Ln .................................................................................. 83
Table: S_Gen_Struct .................................................................................... 84
Table: S_Gen_Struct .................................................................................... 85
Table: S_Label_Ld ....................................................................................... 86
Table: S_Label_Ld ....................................................................................... 87
Table: S_Label_Pt........................................................................................ 88
Table: S_Label_Pt........................................................................................ 89
Table: S_LOMR ........................................................................................... 90
Table: S_LOMR ........................................................................................... 91
Table: S_Nodes ............................................................................................ 92
Table: S_Nodes ............................................................................................ 93
Table: S_Ovrbnkln ....................................................................................... 94
Table: S_Ovrbnkln ....................................................................................... 95
Table: S_Perm_Bmk .................................................................................... 96
Table: S_Perm_Bmk .................................................................................... 97
Table: S_PFD_Ln......................................................................................... 98
Table: S_PFD_Ln......................................................................................... 99
Table: S_PLSS_Ar ..................................................................................... 100
Table: S_PLSS_Ar ..................................................................................... 102


Table: S_PLSS_Ln..................................................................................... 103
Table: S_PLSS_Ln..................................................................................... 105
Table: S_Pol_Ar ......................................................................................... 106
Table: S_Pol_Ar ......................................................................................... 108
Table: S_Pol_Ln......................................................................................... 109
Table: S_Pol_Ln......................................................................................... 110
Table: S_Precip_Gage................................................................................ 111
Table: S_Precip_Gage................................................................................ 112
Table: S_Profil_Basln ................................................................................ 113
Table: S_Profil_Basln ................................................................................ 115
Table: S_Quad_Index................................................................................. 116
Table: S_Quad_Index................................................................................. 117
Table: S_Riv_Mrk...................................................................................... 118
Table: S_Riv_Mrk...................................................................................... 119
Table: S_Shore_Ln..................................................................................... 120
Table: S_Shore_Ln..................................................................................... 121
Table: S_Stn_Start...................................................................................... 122
Table: S_Stn_Start...................................................................................... 123
Table: S_Subbasins .................................................................................... 124
Table: S_Subbasins .................................................................................... 125
Table: S_Trnsport_Ln ................................................................................ 126
Table: S_Trnsport_Ln ................................................................................ 128
Table: S_Water_Gage ................................................................................ 129
Table: S_Water_Gage ................................................................................ 130
Table: S_Wtr_Ar........................................................................................ 131


Table: S_Wtr_Ar........................................................................................ 133
Table: S_Wtr_Ln........................................................................................ 134
Table: S_Wtr_Ln........................................................................................ 136
Table: S_XS ............................................................................................... 137
Table: S_XS ............................................................................................... 140
Table: Study_Info ....................................................................................... 142
Table: Study_Info ....................................................................................... 145
Table: L_Aux_Data.................................................................................... 147
Table: L_Aux_Data.................................................................................... 148
Table: L_Case_Info.................................................................................... 150
Table: L_Case_Info.................................................................................... 151
Table: L_Comm_Info ................................................................................. 152
Table: L_Comm_Info ................................................................................. 154
Table: L_Cst_Model .................................................................................. 155
Table: L_Cst_Model .................................................................................. 157
Table: L_Hydra_Model.............................................................................. 159
Table: L_Hydra_Model.............................................................................. 160
Table: L_Hydro_Model.............................................................................. 161
Table: L_Hydro_Model.............................................................................. 162
Table: L_Media .......................................................................................... 163
Table: L_Media .......................................................................................... 164
Table: L_MT1_LOMC............................................................................... 165
Table: L_MT1_LOMC............................................................................... 166
Table: L_Node_Disch................................................................................ 167
Table: L_Node_Disch................................................................................ 168


Table: L_Pan_Revis ................................................................................... 169
Table: L_Pan_Revis ................................................................................... 170
Table: L_Pol_FHBM ................................................................................. 171
Table: L_Pol_FHBM ................................................................................. 172
Table: L_Regression .................................................................................. 173
Table: L_Regression .................................................................................. 174
Table: L_Stn_Start ..................................................................................... 175
Table: L_Stn_Start ..................................................................................... 176
Table: L_Storm_Curve ............................................................................... 177
Table: L_Storm_Curve ............................................................................... 178
Table: L_Storm_Info.................................................................................. 179
Table: L_Storm_Info.................................................................................. 180
Table: L_Subbas_Disch ............................................................................. 181
Table: L_Subbas_Disch ............................................................................. 182
Table: L_Wtr_Nm...................................................................................... 183
Table: L_Wtr_Nm...................................................................................... 184
Table: L_XS_Ratings ................................................................................. 185
Table: L_XS_Ratings ................................................................................. 187
Table: D_Area_Units ................................................................................. 189
Table: D_Area_Units ................................................................................. 190
Table: D_CBRS_Typ ................................................................................. 191
Table: D_CBRS_Typ ................................................................................. 192
Table: D_Chan_Rep ................................................................................... 193
Table: D_Chan_Rep ................................................................................... 194
Table: D_Discharge_Units ......................................................................... 195


Table: D_Discharge_Units ......................................................................... 196
Table: D_Eros_Method.............................................................................. 197
Table: D_Eros_Method.............................................................................. 198
Table: D_Floodway.................................................................................... 199
Table: D_Floodway.................................................................................... 200
Table: D_Frequency................................................................................... 201
Table: D_Frequency................................................................................... 202
Table: D_Gage ........................................................................................... 203
Table: D_Gage ........................................................................................... 204
Table: D_Hydra.......................................................................................... 205
Table: D_Hydra.......................................................................................... 206
Table: D_Hydro.......................................................................................... 207
Table: D_Hydro.......................................................................................... 208
Table: D_Label_Typ .................................................................................. 209
Table: D_Label_Typ .................................................................................. 210
Table: D_Length_Units.............................................................................. 211
Table: D_Length_Units.............................................................................. 212
Table: D_Ln_Typ ....................................................................................... 213
Table: D_Ln_Typ ....................................................................................... 214
Table: D_Method ....................................................................................... 215
Table: D_Method ....................................................................................... 216
Table: D_Nm_Typ ..................................................................................... 217
Table: D_Nm_Typ ..................................................................................... 218
Table: D_Nodes.......................................................................................... 219
Table: D_Nodes.......................................................................................... 220


Table: D_Panel_Typ .................................................................................. 221
Table: D_Panel_Typ .................................................................................. 222
Table: D_Rd_Stat....................................................................................... 223
Table: D_Rd_Stat....................................................................................... 224
Table: D_Runup_Mdl ................................................................................ 225
Table: D_Runup_Mdl ................................................................................ 226
Table: D_Scale ........................................................................................... 227
Table: D_Scale ........................................................................................... 228
Table: D_Shr_Rough.................................................................................. 229
Table: D_Shr_Rough.................................................................................. 230
Table: D_Shr_Typ...................................................................................... 231
Table: D_Shr_Typ...................................................................................... 232
Table: D_Storms ........................................................................................ 233
Table: D_Storms ........................................................................................ 234
Table: D_Struct_Typ .................................................................................. 235
Table: D_Struct_Typ .................................................................................. 236
Table: D_Surge_Mdl.................................................................................. 237
Table: D_Surge_Mdl.................................................................................. 238
Table: D_Time_Units................................................................................. 239
Table: D_Time_Units................................................................................. 240
Table: D_Trans_Typ .................................................................................. 241
Table: D_Trans_Typ .................................................................................. 242
Table: D_V_Datum .................................................................................... 243
Table: D_V_Datum .................................................................................... 244
Table: D_Velocity_Units ........................................................................... 245


Table: D_Velocity_Units ........................................................................... 246
Table: D_Volume_Units ............................................................................ 247

Table: D_Volume_Units ............................................................................ 248
Table: D_VZone......................................................................................... 249

Table: D_VZone......................................................................................... 250
Table: D_Water_Typ.................................................................................. 251
Table: D_Water_Typ.................................................................................. 252

Table: D_Wave_Mdl.................................................................................. 253
Table: D_Wave_Mdl.................................................................................. 254

Table: D_Zone............................................................................................ 255

Table: D_Zone............................................................................................ 256

L.5 Federal Emergency Management Agency Digital Mapping Information
Checklist ......................................................................................................................... 257

L.6 Metadata Example for Draft Digital Data ............................................................ 261

L.7 Database Table Structure Requirements for Preliminary and Final Digital Flood 
Insurance Rate Map Databases ....................................................................................... 270

Table: S_Base_Index.................................................................................. 270

Table: S_Base_Index.................................................................................. 271
Table: S_BFE ............................................................................................. 272

Table: S_BFE ............................................................................................. 273
Table: S_CBRS .......................................................................................... 274
Table: S_CBRS .......................................................................................... 275

Table: S_Cst_Gage ..................................................................................... 276
Table: S_Cst_Gage ..................................................................................... 278

Table: S_Cst_Tsct_Ln................................................................................ 279
Table: S_Cst_Tsct_Ln................................................................................ 283


Table: S_FIRM_Pan................................................................................... 286
Table: S_FIRM_Pan................................................................................... 289
Table: S_Fld_Haz_Ar ................................................................................ 291
Table: S_Fld_Haz_Ar ................................................................................ 294
Table: S_Fld_Haz_Ln ................................................................................ 296
Table: S_Fld_Haz_Ln ................................................................................ 297
Table: S_Gen_Struct .................................................................................. 298
Table: S_Gen_Struct .................................................................................. 299
Table: S_Label_Ld ..................................................................................... 300
Table: S_Label_Ld ..................................................................................... 301
Table: S_Label_Pt...................................................................................... 302
Table: S_Label_Pt...................................................................................... 303
Table: S_LOMR ......................................................................................... 304
Table: S_LOMR ......................................................................................... 305
Table: S_Nodes .......................................................................................... 306
Table: S_Nodes .......................................................................................... 307
Table: S_Ovrbnkln ..................................................................................... 308
Table: S_Ovrbnkln ..................................................................................... 309
Table: S_Perm_Bmk .................................................................................. 310
Table: S_Perm_Bmk .................................................................................. 311
Table: S_PFD_Ln....................................................................................... 312
Table: S_PFD_Ln....................................................................................... 313
Table: S_PLSS_Ar ..................................................................................... 314
Table: S_PLSS_Ar ..................................................................................... 316
Table: S_PLSS_Ln..................................................................................... 317


Table: S_PLSS_Ln..................................................................................... 319
Table: S_Pol_Ar ......................................................................................... 320
Table: S_Pol_Ar ......................................................................................... 322
Table: S_Pol_Ln......................................................................................... 323
Table: S_Pol_Ln......................................................................................... 324
Table: S_Precip_Gage................................................................................ 325
Table: S_Precip_Gage................................................................................ 326
Table: S_Profil_Basln ................................................................................ 327
Table: S_Profil_Basln ................................................................................ 329
Table: S_Quad_Index................................................................................. 330
Table: S_Quad_Index................................................................................. 331
Table: S_Riv_Mrk...................................................................................... 332
Table: S_Riv_Mrk...................................................................................... 333
Table: S_Shore_Ln..................................................................................... 334
Table: S_Shore_Ln..................................................................................... 335
Table: S_Stn_Start...................................................................................... 336
Table: S_Stn_Start...................................................................................... 337
Table: S_Subbasins .................................................................................... 338
Table: S_Subbasins .................................................................................... 339
Table: S_Trnsport_Ln ................................................................................ 340
Table: S_Trnsport_Ln ................................................................................ 342
Table: S_Water_Gage ................................................................................ 343
Table: S_Water_Gage ................................................................................ 344
Table: S_Wtr_Ar........................................................................................ 345
Table: S_Wtr_Ar........................................................................................ 346


Table: S_Wtr_Ln........................................................................................ 347
Table: S_Wtr_Ln........................................................................................ 349
Table: S_XS ............................................................................................... 350
Table: S_XS ............................................................................................... 353
Table: Study_Info ....................................................................................... 355
Table: Study_Info ....................................................................................... 358
Table: L_Aux_Data.................................................................................... 360
Table: L_Aux_Data.................................................................................... 361
Table: L_Case_Info.................................................................................... 363
Table: L_Case_Info.................................................................................... 364
Table: L_Comm_Info ................................................................................. 365
Table: L_Comm_Info ................................................................................. 367
Table: L_Cst_Model .................................................................................. 368
Table: L_Cst_Model .................................................................................. 370
Table: L_Hydra_Model.............................................................................. 372
Table: L_Hydra_Model.............................................................................. 373
Table: L_Hydro_Model.............................................................................. 374
Table: L_Hydro_Model.............................................................................. 375
Table: L_Media .......................................................................................... 376
Table: L_Media .......................................................................................... 377
Table: L_MT1_LOMC............................................................................... 378
Table: L_MT1_LOMC............................................................................... 380
Table: L_Node_Disch................................................................................ 381
Table: L_Node_Disch................................................................................ 382
Table: L_Pan_Revis ................................................................................... 383


Table: L_Pan_Revis ................................................................................... 384
Table: L_Pol_FHBM ................................................................................. 385

Table: L_Pol_FHBM ................................................................................. 386
Table: L_Regression .................................................................................. 387

Table: L_Regression .................................................................................. 388
Table: L_Stn_Start ..................................................................................... 389
Table: L_Stn_Start ..................................................................................... 390

Table: L_Storm_Curve ............................................................................... 391
Table: L_Storm_Curve ............................................................................... 392

Table: L_Storm_Info.................................................................................. 393
Table: L_Storm_Info.................................................................................. 394
Table: L_Subbas_Disch ............................................................................. 395

Table: L_Subbas_Disch ............................................................................. 396
Table: L_XS_Ratings ................................................................................. 397

Table: L_XS_Ratings ................................................................................. 399
L.8 Metadata Example for Preliminary and Final Digital Flood Insurance Rate Map 
Databases ........................................................................................................................ 401
L.9 Domain Tables...................................................................................................... 411

Table: D_Area_Units ................................................................................. 411

Table: D_CBRS_Typ ................................................................................. 412
Table: D_Chan_Rep ................................................................................... 413
Table: D_Discharge_Units ......................................................................... 414

Table: D_Eros_Method.............................................................................. 415
Table: D_Floodway.................................................................................... 416

Table: D_Frequency................................................................................... 417
Table: D_Gage ........................................................................................... 418


Table: D_Hydra.......................................................................................... 419
Table: D_Hydro.......................................................................................... 421
Table: D_Label_Typ .................................................................................. 423
Table: D_Length_Units.............................................................................. 424
Table: D_Ln_Typ ....................................................................................... 425
Table: D_Method ....................................................................................... 427
Table: D_Nm_Typ ..................................................................................... 428
Table: D_Nodes.......................................................................................... 431
Table: D_Panel_Typ .................................................................................. 432
Table: D_Rd_Stat....................................................................................... 433
Table: D_Runup_Mdl ................................................................................ 434
Table: D_Scale ........................................................................................... 435
Table: D_Shr_Rough.................................................................................. 436
Table: D_Shr_Typ...................................................................................... 437
Table: D_Storms ........................................................................................ 438
Table: D_Struct_Typ .................................................................................. 439
Table: D_Surge_Mdl.................................................................................. 441
Table: D_Time_Units................................................................................. 442
Table: D_Trans_Typ .................................................................................. 443
Table: D_V_Datum .................................................................................... 444
Table: D_Velocity_Units ........................................................................... 445
Table: D_Volume_Units ............................................................................ 446
Table: D_VZone......................................................................................... 447
Table: D_Water_Typ.................................................................................. 448
Table: D_Wave_Mdl.................................................................................. 451


Summary of Changes............................................................................................................i

L.1 Digital Flood Insurance Rate Map Database Overview......................................... 16

Database Design Decisions ....................................................................................... 22

L.1.1 Spatial Data and Tabular Data .................................................................. 22

L.1.2 Draft Digital Data Versus Preliminary and Final Digital Flood Insurance 
Rate Map Databases.................................................................................................. 23

L.2 Preparation of Draft Digital Data ........................................................................... 24

L.2.1 General...................................................................................................... 24

L.2.2 Coordination.............................................................................................. 25

L.2.2.1 Data Sources ......................................................................................... 26

L.2.3 Standards ................................................................................................... 27

L.2.4 Horizontal and Vertical Control................................................................ 27

L.2.5 Digital Data Structure ............................................................................... 28

L.2.5.1 Tiling ..................................................................................................... 28
L.2.5.2 Topology ............................................................................................... 28
L.2.5.3 Edgematching........................................................................................ 29
L.2.5.4 Coincident Features............................................................................... 30
L.2.5.5 Precise Features..................................................................................... 31
L.2.5.6 Data Compilation.................................................................................. 31
L.2.5.7 Digitizing .............................................................................................. 31
L.2.5.8 Relationship of Base Map to Flood Hazard Data ................................. 32
L.2.5.9 Computer Assisted Drafting and Design or Geographic Information
System Preparation................................................................................................. 33
L.2.5.10 Table Structure......................................................................................33
L.2.5.11 Spatial Files for Computer Assisted Drafting and Design Format ....... 36

L.2.6 Quality Control ......................................................................................... 40

L.2.7 Deliverables .............................................................................................. 40

L.2.7.1 Hardcopy Deliverables.......................................................................... 41
L.2.7.2 Digital Deliverables .............................................................................. 41

L.2.8 Metadata.................................................................................................... 44

L.3 Preparation of Preliminary and Final Digital Flood Insurance Rate Map
Databases .......................................................................................................................... 45

L.3.1 General...................................................................................................... 45


L.3.2 Coordination.............................................................................................. 45
L.3.2.1 Data Sources ......................................................................................... 45
L.3.3 Standards ................................................................................................... 46

L.3.4 Horizontal and Vertical Control................................................................ 46

L.3.5 Data Structure ........................................................................................... 47

L.3.5.1 Tiling ..................................................................................................... 47
L.3.5.2 Topology ............................................................................................... 47
L.3.5.3 Edgematching........................................................................................ 48
L.3.5.4 Coincident Features............................................................................... 48
L.3.5.5 Precise Features..................................................................................... 48
L.3.5.6 Data Compilation.................................................................................. 48
L.3.5.7 Digitizing .............................................................................................. 49
L.3.5.8 Relationship of Base Map to Flood Hazard Data ................................. 49
L.3.5.9 Computer Assisted Drafting and Design or Geographic Information
System Preparation................................................................................................. 50
L.3.5.10 Table Structure ...................................................................................... 50
L.3.5.11 Spatial Files........................................................................................... 50

L.3.6 Quality Control ......................................................................................... 52

L.3.7 Deliverables .............................................................................................. 52

L.3.7.1 Hardcopy Deliverables.......................................................................... 52
L.3.7.2 Digital Deliverables .............................................................................. 52

L.3.8 Metadata.................................................................................................... 54
L.4 Database Table Structure Requirements for Draft Digital Data............................. 56

Table: S_Base_Index.................................................................................... 56

Table: S_Base_Index.................................................................................... 57
Table: S_BFE ............................................................................................... 58
Table: S_BFE ............................................................................................... 59

Table: S_CBRS ............................................................................................ 60
Table: S_CBRS ............................................................................................ 61

Table: S_Cst_Gage ....................................................................................... 62
Table: S_Cst_Gage ....................................................................................... 64
Table: S_Cst_Tsct_Ln.................................................................................. 65


Table: S_Cst_Tsct_Ln.................................................................................. 69
Table: S_FIRM_Pan..................................................................................... 72
Table: S_FIRM_Pan..................................................................................... 75
Table: S_Fld_Haz_Ar .................................................................................. 77
Table: S_Fld_Haz_Ar .................................................................................. 80
Table: S_Fld_Haz_Ln .................................................................................. 82
Table: S_Fld_Haz_Ln .................................................................................. 83
Table: S_Gen_Struct .................................................................................... 84
Table: S_Gen_Struct .................................................................................... 85
Table: S_Label_Ld ....................................................................................... 86
Table: S_Label_Ld ....................................................................................... 87
Table: S_Label_Pt........................................................................................ 88
Table: S_Label_Pt........................................................................................ 89
Table: S_LOMR ........................................................................................... 90
Table: S_LOMR ........................................................................................... 91
Table: S_Nodes ............................................................................................ 92
Table: S_Nodes ............................................................................................ 93
Table: S_Ovrbnkln ....................................................................................... 94
Table: S_Ovrbnkln ....................................................................................... 95
Table: S_Perm_Bmk .................................................................................... 96
Table: S_Perm_Bmk .................................................................................... 97
Table: S_PFD_Ln......................................................................................... 98
Table: S_PFD_Ln......................................................................................... 99
Table: S_PLSS_Ar ..................................................................................... 100
Table: S_PLSS_Ar ..................................................................................... 102


Table: S_PLSS_Ln..................................................................................... 103
Table: S_PLSS_Ln..................................................................................... 105
Table: S_Pol_Ar ......................................................................................... 106
Table: S_Pol_Ar ......................................................................................... 108
Table: S_Pol_Ln......................................................................................... 109
Table: S_Pol_Ln......................................................................................... 110
Table: S_Precip_Gage................................................................................ 111
Table: S_Precip_Gage................................................................................ 112
Table: S_Profil_Basln ................................................................................ 113
Table: S_Profil_Basln ................................................................................ 115
Table: S_Quad_Index................................................................................. 116
Table: S_Quad_Index................................................................................. 117
Table: S_Riv_Mrk...................................................................................... 118
Table: S_Riv_Mrk...................................................................................... 119
Table: S_Shore_Ln..................................................................................... 120
Table: S_Shore_Ln..................................................................................... 121
Table: S_Stn_Start...................................................................................... 122
Table: S_Stn_Start...................................................................................... 123
Table: S_Subbasins .................................................................................... 124
Table: S_Subbasins .................................................................................... 125
Table: S_Trnsport_Ln ................................................................................ 126
Table: S_Trnsport_Ln ................................................................................ 128
Table: S_Water_Gage ................................................................................ 129
Table: S_Water_Gage ................................................................................ 130
Table: S_Wtr_Ar........................................................................................ 131


Table: S_Wtr_Ar........................................................................................ 133
Table: S_Wtr_Ln........................................................................................ 134
Table: S_Wtr_Ln........................................................................................ 136
Table: S_XS ............................................................................................... 137
Table: S_XS ............................................................................................... 140
Table: Study_Info ....................................................................................... 142
Table: Study_Info ....................................................................................... 145
Table: L_Aux_Data.................................................................................... 147
Table: L_Aux_Data.................................................................................... 148
Table: L_Case_Info.................................................................................... 150
Table: L_Case_Info.................................................................................... 151
Table: L_Comm_Info ................................................................................. 152
Table: L_Comm_Info ................................................................................. 154
Table: L_Cst_Model .................................................................................. 155
Table: L_Cst_Model .................................................................................. 157
Table: L_Hydra_Model.............................................................................. 159
Table: L_Hydra_Model.............................................................................. 160
Table: L_Hydro_Model.............................................................................. 161
Table: L_Hydro_Model.............................................................................. 162
Table: L_Media..........................................................................................163
Table: L_Media .......................................................................................... 164
Table: L_MT1_LOMC............................................................................... 165
Table: L_MT1_LOMC............................................................................... 166
Table: L_Node_Disch................................................................................ 167
Table: L_Node_Disch................................................................................ 168


Table: L_Pan_Revis ................................................................................... 169
Table: L_Pan_Revis ................................................................................... 170
Table: L_Pol_FHBM ................................................................................. 171
Table: L_Pol_FHBM ................................................................................. 172
Table: L_Regression .................................................................................. 173
Table: L_Regression .................................................................................. 174
Table: L_Stn_Start ..................................................................................... 175
Table: L_Stn_Start ..................................................................................... 176
Table: L_Storm_Curve ............................................................................... 177
Table: L_Storm_Curve............................................................................... 178
Table: L_Storm_Info.................................................................................. 179
Table: L_Storm_Info.................................................................................. 180
Table: L_Subbas_Disch ............................................................................. 181
Table: L_Subbas_Disch ............................................................................. 182
Table: L_Wtr_Nm...................................................................................... 183
Table: L_Wtr_Nm...................................................................................... 184
Table: L_XS_Ratings ................................................................................. 185
Table: L_XS_Ratings ................................................................................. 187
Table: D_Area_Units ................................................................................. 189
Table: D_Area_Units ................................................................................. 190
Table: D_CBRS_Typ ................................................................................. 191
Table: D_CBRS_Typ ................................................................................. 192
Table: D_Chan_Rep ................................................................................... 193
Table: D_Chan_Rep ................................................................................... 194
Table: D_Discharge_Units ......................................................................... 195


Table: D_Discharge_Units ......................................................................... 196
Table: D_Eros_Method.............................................................................. 197
Table: D_Eros_Method.............................................................................. 198
Table: D_Floodway.................................................................................... 199
Table: D_Floodway.................................................................................... 200
Table: D_Frequency................................................................................... 201
Table: D_Frequency................................................................................... 202
Table: D_Gage ........................................................................................... 203
Table: D_Gage ........................................................................................... 204
Table: D_Hydra.......................................................................................... 205
Table: D_Hydra.......................................................................................... 206
Table: D_Hydro.......................................................................................... 207
Table: D_Hydro.......................................................................................... 208
Table: D_Label_Typ .................................................................................. 209
Table: D_Label_Typ .................................................................................. 210
Table: D_Length_Units.............................................................................. 211
Table: D_Length_Units.............................................................................. 212
Table: D_Ln_Typ ....................................................................................... 213
Table: D_Ln_Typ ....................................................................................... 214
Table: D_Method ....................................................................................... 215
Table: D_Method ....................................................................................... 216
Table: D_Nm_Typ ..................................................................................... 217
Table: D_Nm_Typ ..................................................................................... 218
Table: D_Nodes.......................................................................................... 219
Table: D_Nodes.......................................................................................... 220


Table: D_Panel_Typ .................................................................................. 221
Table: D_Panel_Typ .................................................................................. 222
Table: D_Rd_Stat....................................................................................... 223
Table: D_Rd_Stat....................................................................................... 224
Table: D_Runup_Mdl ................................................................................ 225
Table: D_Runup_Mdl ................................................................................ 226
Table: D_Scale ........................................................................................... 227
Table: D_Scale ........................................................................................... 228
Table: D_Shr_Rough.................................................................................. 229
Table: D_Shr_Rough.................................................................................. 230
Table: D_Shr_Typ...................................................................................... 231
Table: D_Shr_Typ...................................................................................... 232
Table: D_Storms ........................................................................................ 233
Table: D_Storms ........................................................................................ 234
Table: D_Struct_Typ .................................................................................. 235
Table: D_Struct_Typ .................................................................................. 236
Table: D_Surge_Mdl.................................................................................. 237
Table: D_Surge_Mdl.................................................................................. 238
Table: D_Time_Units................................................................................. 239
Table: D_Time_Units................................................................................. 240
Table: D_Trans_Typ .................................................................................. 241
Table: D_Trans_Typ .................................................................................. 242
Table: D_V_Datum .................................................................................... 243
Table: D_V_Datum .................................................................................... 244
Table: D_Velocity_Units ........................................................................... 245


Table: D_Velocity_Units ........................................................................... 246
Table: D_Volume_Units ............................................................................ 247

Table: D_Volume_Units ............................................................................ 248
Table: D_VZone......................................................................................... 249

Table: D_VZone......................................................................................... 250
Table: D_Water_Typ.................................................................................. 251
Table: D_Water_Typ.................................................................................. 252

Table: D_Wave_Mdl.................................................................................. 253
Table: D_Wave_Mdl.................................................................................. 254

Table: D_Zone............................................................................................ 255

Table: D_Zone............................................................................................ 256

L.5 Federal Emergency Management Agency Digital Mapping Information Checklist
257

L.6 Metadata Example for Draft Digital Data ............................................................ 261

L.7 Database Table Structure Requirements for Preliminary and Final Digital Flood 
Insurance Rate Map Databases ....................................................................................... 270

Table: S_Base_Index.................................................................................. 270

Table: S_Base_Index.................................................................................. 271
Table: S_BFE ............................................................................................. 272

Table: S_BFE ............................................................................................. 273
Table: S_CBRS .......................................................................................... 274
Table: S_CBRS .......................................................................................... 275

Table: S_Cst_Gage ..................................................................................... 276
Table: S_Cst_Gage ..................................................................................... 278

Table: S_Cst_Tsct_Ln................................................................................ 279
Table: S_Cst_Tsct_Ln................................................................................ 283


Table: S_FIRM_Pan................................................................................... 286
Table: S_FIRM_Pan................................................................................... 289
Table: S_Fld_Haz_Ar ................................................................................ 291
Table: S_Fld_Haz_Ar ................................................................................ 294
Table: S_Fld_Haz_Ln ................................................................................ 296
Table: S_Fld_Haz_Ln ................................................................................ 297
Table: S_Gen_Struct .................................................................................. 298
Table: S_Gen_Struct .................................................................................. 299
Table: S_Label_Ld ..................................................................................... 300
Table: S_Label_Ld ..................................................................................... 301
Table: S_Label_Pt...................................................................................... 302
Table: S_Label_Pt...................................................................................... 303
Table: S_LOMR ......................................................................................... 304
Table: S_LOMR ......................................................................................... 305
Table: S_Nodes .......................................................................................... 306
Table: S_Nodes .......................................................................................... 307
Table: S_Ovrbnkln ..................................................................................... 308
Table: S_Ovrbnkln ..................................................................................... 309
Table: S_Perm_Bmk .................................................................................. 310
Table: S_Perm_Bmk .................................................................................. 311
Table: S_PFD_Ln....................................................................................... 312
Table: S_PFD_Ln....................................................................................... 313
Table: S_PLSS_Ar ..................................................................................... 314
Table: S_PLSS_Ar ..................................................................................... 316
Table: S_PLSS_Ln..................................................................................... 317


Table: S_PLSS_Ln..................................................................................... 319
Table: S_Pol_Ar ......................................................................................... 320
Table: S_Pol_Ar ......................................................................................... 322
Table: S_Pol_Ln......................................................................................... 323
Table: S_Pol_Ln......................................................................................... 324
Table: S_Precip_Gage................................................................................ 325
Table: S_Precip_Gage................................................................................ 326
Table: S_Profil_Basln ................................................................................ 327
Table: S_Profil_Basln ................................................................................ 329
Table: S_Quad_Index................................................................................. 330
Table: S_Quad_Index................................................................................. 331
Table: S_Riv_Mrk...................................................................................... 332
Table: S_Riv_Mrk...................................................................................... 333
Table: S_Shore_Ln..................................................................................... 334
Table: S_Shore_Ln..................................................................................... 335
Table: S_Stn_Start...................................................................................... 336
Table: S_Stn_Start...................................................................................... 337
Table: S_Subbasins .................................................................................... 338
Table: S_Subbasins .................................................................................... 339
Table: S_Trnsport_Ln ................................................................................ 340
Table: S_Trnsport_Ln ................................................................................ 342
Table: S_Water_Gage ................................................................................ 343
Table: S_Water_Gage ................................................................................ 344
Table: S_Wtr_Ar........................................................................................ 345
Table: S_Wtr_Ar........................................................................................ 346


Table: S_Wtr_Ln........................................................................................ 347
Table: S_Wtr_Ln........................................................................................ 349
Table: S_XS ............................................................................................... 350
Table: S_XS ............................................................................................... 353
Table: Study_Info ....................................................................................... 355
Table: Study_Info ....................................................................................... 358
Table: L_Aux_Data.................................................................................... 360
Table: L_Aux_Data.................................................................................... 361
Table: L_Case_Info.................................................................................... 363
Table: L_Case_Info.................................................................................... 364
Table: L_Comm_Info ................................................................................. 365
Table: L_Comm_Info ................................................................................. 367
Table: L_Cst_Model .................................................................................. 368
Table: L_Cst_Model .................................................................................. 370
Table: L_Hydra_Model.............................................................................. 372
Table: L_Hydra_Model.............................................................................. 373
Table: L_Hydro_Model.............................................................................. 374
Table: L_Hydro_Model.............................................................................. 375
Table: L_Media .......................................................................................... 376
Table: L_Media .......................................................................................... 377
Table: L_MT1_LOMC............................................................................... 378
Table: L_MT1_LOMC............................................................................... 380
Table: L_Node_Disch................................................................................ 381
Table: L_Node_Disch................................................................................ 382
Table: L_Pan_Revis ................................................................................... 383


Table: L_Pan_Revis ................................................................................... 384
Table: L_Pol_FHBM ................................................................................. 385

Table: L_Pol_FHBM ................................................................................. 386
Table: L_Regression .................................................................................. 387

Table: L_Regression .................................................................................. 388
Table: L_Stn_Start ..................................................................................... 389
Table: L_Stn_Start ..................................................................................... 390

Table: L_Storm_Curve ............................................................................... 391
Table: L_Storm_Curve ............................................................................... 392

Table: L_Storm_Info.................................................................................. 393
Table: L_Storm_Info.................................................................................. 394
Table: L_Subbas_Disch ............................................................................. 395

Table: L_Subbas_Disch ............................................................................. 396
Table: L_XS_Ratings ................................................................................. 397

Table: L_XS_Ratings ................................................................................. 399
L.8 Metadata Example for Preliminary and Final Digital Flood Insurance Rate Map 
Databases ........................................................................................................................ 401
L.9 Domain Tables...................................................................................................... 411

Table: D_Area_Units ................................................................................. 411

Table: D_CBRS_Typ ................................................................................. 412
Table: D_Chan_Rep ................................................................................... 413
Table: D_Discharge_Units ......................................................................... 414

Table: D_Eros_Method.............................................................................. 415
Table: D_Floodway.................................................................................... 416

Table: D_Frequency................................................................................... 417
Table: D_Gage ........................................................................................... 418


Table: D_Hydra.......................................................................................... 419
Table: D_Hydro.......................................................................................... 421
Table: D_Label_Typ .................................................................................. 423
Table: D_Length_Units.............................................................................. 424
Table: D_Ln_Typ ....................................................................................... 425
Table: D_Method ....................................................................................... 427
Table: D_Nm_Typ ..................................................................................... 428
Table: D_Nodes.......................................................................................... 431
Table: D_Panel_Typ .................................................................................. 432
Table: D_Rd_Stat....................................................................................... 433
Table: D_Runup_Mdl ................................................................................ 434
Table: D_Scale ........................................................................................... 435
Table: D_Shr_Rough.................................................................................. 436
Table: D_Shr_Typ...................................................................................... 437
Table: D_Storms ........................................................................................ 438
Table: D_Struct_Typ .................................................................................. 439
Table: D_Surge_Mdl.................................................................................. 441
Table: D_Time_Units................................................................................. 442
Table: D_Trans_Typ .................................................................................. 443
Table: D_V_Datum .................................................................................... 444
Table: D_Velocity_Units ........................................................................... 445
Table: D_Volume_Units ............................................................................ 446
Table: D_VZone......................................................................................... 447
Table: D_Water_Typ.................................................................................. 448
Table: D_Wave_Mdl.................................................................................. 451


Table: D_Zone............................................................................................ 452 


Appendix L 

Draft Digital Data and Digital Flood Insurance Rate 
Map Database Specifications 

The purpose of this Appendix is to provide guidance and specifications to the Mapping 
Partner that prepares draft digital data for Digital Flood Insurance Rate Map (DFIRM) 
production and the Mapping Partner that prepares the Preliminary and Final DFIRM and 
databases for transfer to the Federal Emergency Management Agency (FEMA). For a 
particular Flood Map Project, the FEMA Lead may assign both tasks to one Mapping 
Partner or each task to different Mapping Partners. This Appendix is not intended to 
specify in-process compilation or digitizing procedures, but rather to present 
specifications and requirements for output and deliverables. 

L.1 Digital Flood Insurance Rate Map Database 
Overview 

The FEMA Geographic Information System (GIS) databases will store the digital data 
used in the map production process, as well as the engineering backup data for floodplain 
studies. These databases will provide a standard, systematic method for FEMA to 
distribute comprehensive details of flood studies to the public and others in a digital 
format. 

Preparing these data in digital format has significant advantages. Digital data allow for 
more efficient storage, update, records search and distribution. The most significant 
advantage is that the data are designed to work within a GIS environment. This means 
that the FEMA database can be used for automated analyses that are costly and 
impractical with paper products and is compatible with Internet applications. 

FEMA will collect as much data as possible in digital format, and archive the data in the 
GIS database for each DFIRM created. For publication of these data, FEMA will provide 
two versions of the DFIRM database. The simplified version is called the Standard 
DFIRM Database. The Standard DFIRM Database is provided to end users who do not 
require the complete engineering backup data; however, it is not intended to limit the 
scope of the GIS data collected and submitted to FEMA. The full GIS database that 
contains all of the available flood study information is called the Enhanced DFIRM 
Database 

The Standard DFIRM Database was designed to present the effective flood hazard 
information published by FEMA. Users who only need to know whether a structure is in 
or out of the Special Flood Hazard Area (SFHA), or what the base flood elevation is for a 
location will be able to use the Standard DFIRM Database. Users who want to reference 
the engineering analyses or utilize any of the supporting data behind the effective flood 
hazard data will need to use the Enhanced DFIRM Database. 


This Appendix includes the specification for the Standard DFIRM Database and the core 
elements of the Enhanced DFIRM Database. All of the Standard DFIRM Database 
information is contained within the Enhanced DFIRM Database. In the sections below 
that detail the database structure, some database fields and some database tables are 
identified as Enhanced. That means these fields or tables are only included with full 
GIS database that is built for a particular study. They are not included in the easier to use 
version, the Standard DFIRM Database, that is also available for the same study. 

The amount of data that will be captured digitally and stored in the Enhanced DFIRM 
Database will vary for each flood study. In general, the production of any digital map 
will result in a complete Standard DFIRM Database. However, most studies will also 
have some additional data that will be stored in the Enhanced DFIRM Database. Even 
studies where existing effective flood hazard analyses are used to produce updated digital 
maps may include easily accessible elements of the Enhanced DFIRM Database. For 
new studies where new flood hazard analyses are performed, the core elements of the 
Enhanced Database described will be populated. For each digital map update undertaken, 
the Mapping Partner should coordinate with the FEMA Lead to determine how much of 
the Enhanced DFIRM Database should be completed. 

For Preliminary or Final DFIRMs, all of the tables in the DFIRM database are required if 
they apply to the DFIRM being created. Some tables, like those that depict coastal 
features, do not apply to every DFIRM. The Mapping Partner that creates the DFIRM 
shall ensure that all of the applicable tables in the DFIRM database have been completed 
and documented in the metadata. Generally, the DFIRM database for a new DFIRM will 
cover the entire jurisdiction. Detailed specifications for the Preliminary or Final DFIRM 
database are provided in Section L.3. A summary of the standard DFIRM database tables 
is provided in Table L-1. 


Table L-1. DFIRM Database Table Summary 
DFIRM Table 
Name 
Table 
Type 
Table Description 
L_Aux_Data Lookup Information about auxiliary data. 
L_Case_Info Lookup Information about data specific to the study. 
L_Comm_Info Lookup Information about each community on the DFIRM 
L_Cst_Model Lookup Information about coastal models used in the engineering analysis. 
L_Hydra_Model Lookup Information about hydraulic models used in the engineering analysis. 
L_Hydro_Model Lookup Information about hydrologic models used in the engineering analysis. 
L_Media Lookup Information about archived media that is linked to a spatial object. 
L_MT1_LOMC Lookup Information about LOMCs on the DFIRM 
L_Node_Disch Lookup Information about hydrologic routing. 
L_Pan_Revis Lookup Information about revisions to each FIRM panel 
L_Pol_FHBM Lookup Information about revisions to FHBMs for each community 
L_Regression Lookup Information about regression equations utilized in the hydrologic 
modeling. 
L_Stn_Start Lookup Location and attributes for starting points for stream distance 
measurements 
L_Storm_Curve Lookup Information about Depth-Duration-Frequency and Intensity-Duration-
Frequency relationships. 
L_Storm_Info Lookup Information about basic precipitation patterns. 
L_Subbas_Disch Lookup Information about outflow data for each subbasin and recurrence 
interval in the hydrologic analysis. 
L_Wtr_Nm Lookup Information about hydrographic features on the DFIRM 
L_XS_Ratings Lookup Information about cross sections. 
S_Base_Index Spatial Location and attributes for a tiling index for raster data used for the 
DFIRM 
S_BFE Spatial Location and attributes for base flood elevations lines shown on 
DFIRM 
S_CBRS Spatial Location and attributes for Coastal Barrier Resource System units on 
the DFIRM 
S_Cst_Gage Spatial Location and attributes for the coastal gages for the study area. 
S_Cst_Tsct_Ln Spatial Location and attributes for coastal transect lines shown on the DFIRM 
S_FIRM_Pan Spatial Location and attributes for DFIRM hardcopy map panels 
S_Fld_Haz_Ar Spatial Location and attributes for flood insurance risk zones on the DFIRM 
S_Fld_Haz_Ln Spatial Location and attributes for boundaries of flood insurance risk zones on 
the DFIRM 
S_Gen_Struct Spatial Location and attributes for flood control structures shown on the 
DFIRM 
S_Label_Ld Spatial Location and attributes for leader lines on transportation and 
hydrography labels shown on the DFIRM 
S_Label_Pt Spatial Location and attributes for transportation and hydrography labels 
shown on the DFIRM 
S_LOMR Spatial Location and attributes for LOMRs on the DFIRM 
S_Nodes Spatial Location and attributes of points used to define the topology of the 
hydrologic network. 
S_Ovrbnkln Spatial Location and attributes for the overbank flow lines features for the 
study area. 
S_Perm_Bmk Spatial Location and attributes for bench marks on the DFIRM 
S_PFD_Ln Spatial Location and attributes for the primary frontal dune features for the 
coastal study area. 
S_PLSS_Ar Spatial Location and attributes of sections, townships and ranges on the 
DFIRM 
S_PLSS_Ln Spatial Location and attributes section lines, township lines and range lines on 


the DFIRM 
S_Pol_Ar Spatial Location and attributes for political jurisdictions shown on the DFIRM 
S_Pol_Ln Spatial Location and attributes for political boundaries shown on the DFIRM 
S_Precip_Gage Spatial Location and attributes for rain gages used in developing the 
hydrologic analysis. 
S_Profil_Basln Spatial Location and attributes for profile baseline and stream centerline 
features for the study area. 
S_Quad_Index Spatial Location and attributes for USGS quadrangle maps covering the 
DFIRM area 
S_Riv_Mrk Spatial Location and attributes for river mile markers shown on the DFIRM 
S_Shore_Ln Spatial Location and attributes for the shoreline used in the coastal flood 
hazard model. 
S_Stn_Start Spatial Location and attributes for station points. 
S_Subbasins Spatial Location and attributes for subbasins in the hydrologic analysis. 
S_Trnsport_Ln Spatial Location and attributes for roads, railroads and other transportation 
features shown on the DFIRM 
S_Water_Gage Spatial Location and attributes for non-rain gages used in developing the 
hydrologic analysis. 
S_Wtr_Ar Spatial Location and attributes for hydrography features shown on DFIRM 
S_Wtr_Ln Spatial Location and attributes for hydrography features shown on DFIRM 
S_XS Spatial Location and attributes for cross-section lines in the area covered by 
the DFIRM 
Study_Info Non-
Spatial 
General information about the DFIRM 

Mapping Partners that are assigned other tasks for a Flood Map Project will normally 
produce draft study components and draft DFIRM digital data. For Mapping Partners 
that create draft DFIRM digital data, not all the tables in the DFIRM database will apply. 
These Mapping Partners will often only submit data that cover the geographic area of 
their work. The tables that are applicable to a specific Flood Map Project will vary, 
depending on the specific scope of that activity. Table L-2 presents the DFIRM database 
tables that apply to specific components of a Flood Map Project. The scope of a particular 
project could include several of these activities and, therefore, all of the tables from each 
of the activities involved in the project will likely apply. Most Flood Map Projects will 
include the requirement of a digital base map that meets the requirements as outlined in 
Appendix K of these Guidelines. 


L-20


S_PFD_Ln S_PFD_Ln 
S_PLSS_Ar S_PLSS_Ar 
S_PLSS_Ln S_PLSS_Ln 
S_Pol_Ar S_Pol_Ar 
S_Pol_Ln S_Pol_Ln 
S_Precip_Gage S_Precip_Gage 
S_Profil_Basln S_Profil_Basln 
S_Quad_Index S_Quad_Index 
S_Riv_Mrk S_Riv_Mrk 
S_Shore_Ln S_Shore_Ln 
S_Stn_Start S_Stn_Start 
S_Subbasins S_Subbasins 
S_Trnsport_Ln S_Trnsport_Ln 
S_Water_Gage S_Water_Gage 
S_Wtr_Ar S_Wtr_Ar 
S_Wtr_Ln S_Wtr_Ln 
S_XS S_XS 
Study_Info Study_Info 

L-21


Database Design Decisions 

To facilitate the ease of use of the DFIRM database, FEMA will avoid the use of abbreviations 
and codes in the published data where feasible. 

Where possible, all mapping and engineering data elements will be linked to physical geographic 
features that are georeferenced. A GIS has the ability to precisely overlay the mapping and 
engineering data. This approach supports a wide variety of existing and visionary FEMA 
engineering and mapping products, such as digital mapping; automated hydrologic and hydraulic 
modeling, automated mapping, web-based publishing, and direct links between modeling and 
mapping elements. 

The DFIRM database is not intended to be used to produce an exact replica of the printed Flood 
Insurance Rate Map (FIRM). Instead, the DFIRM database is designed to allow a GIS user 
access to all of the information conveyed on the FIRM in a way that can best take advantage of 
the automated analysis capabilities of GIS. FEMA will provide a companion product in the form 
of a scanned or raster image of the hardcopy DFIRM that will allow users to reprint exact 
replicas of the whole FIRM or portions of the FIRM. 

The DFIRM database will be designed to be usable in a standard Relational Database 
Management System (RDBMS), but will be software independent. Therefore, the products are 
defined as flat tables in public domain formats (e.g., ESRI Shapefiles, MapInfo MIF files). 
Users can import these formats into a wide variety of software packages. These file formats 
manage GIS data in discrete files, generally organized by data theme. As a result, they do not 
support the inter-table relationships and data integrity enforcement capabilities of an RDBMS. 
However, the data produced by FEMA will be designed, tested to follow these rules, and fully 
compatible with an RDBMS. 

L.1.1 Spatial Data and Tabular Data 

The complete DFIRM database product is a GIS database made up of spatial data describing the 
location of features on the earth and tabular data that describe the attributes of these spatial 
features. The tables described in Sections L.4 and L.7 that begin with S_ have a spatial 
component associated with them. 

FEMA will distribute Preliminary and Final DFIRM databases to end users in GIS formats where 
the links between the spatial data and the attribute data are inherent in the data structure. 


L.1.2 Draft Digital Data Versus Preliminary and Final Digital Flood 
Insurance Rate Map Databases 

To facilitate the submittal of digital flood hazard mapping data from all Mapping Partners, 
FEMA has established more flexible requirements for submitting draft DFIRM digital data than 
for Preliminary or Final DFIRM databases. Sections L.2 and L.4 provide options for submitting 
draft DFIRM spatial data in a Computer Assisted Drafting and Design (CADD) structure or a 
GIS structure. Mapping Partners preparing draft DFIRM data have the option of using one of the 
draft data formats or using the Preliminary or Final DFIRM database format described in L.3 and 
L.7. The Mapping Partner preparing draft DFIRM data should choose the option that works best 
for the project. Mapping Partners preparing Preliminary or Final DFIRM databases must follow 
the format described in L.3 and L.7. 

Section L.4 also provides an option for the attribute table structure for DFIRMs tha t employs a 
more sophisticated relational structure. This option allows Mapping Partners that create draft 
DFIRM digital data to take advantage of relational database techniques to ensure data 
consistency and reduce database size. The Preliminary and Final DFIRM Databases have a 
simpler structure for ease of use by the general public. The primary difference between the draft 
table structure and the Preliminary and Final table structure is that domain tables are used in the 
draft structure and are not used in the Preliminary and Final structure. 

The following discussion highlights the differences between the attribute table structure option 
available for draft DFIRM digital data and the attribute table structure for Preliminary and Final 
DFIRM Databases. Domain tables (tables in the database that begin with D_) were established 
to assist FEMAs Mapping Partners in the creation of the draft DFIRM database. These domain 
tables provide the Mapping Partner with valid or preferred attribute values for specific fields. A 
domain table also helps minimize entry differences by standardizing the value. For example, 
without domain tables, one user might enter floodway while another user might enter 
FLDWY while completing the FLOODWAY field in the S_Fld_Haz_Ar table. While both of 
these entries reflect the same idea, the inconsistency between the two forms makes it difficult to 
group similar features together. Using a domain table ensures that both users enter the same 
value (i.e., floodway) to describe the same feature. To capture local characteristics not included 
in the domain table, Mapping Partners also may add and use their own values in the domain table 
(e.g., a more restrictive locally regulated floodway could be added to the accepted domain values 
as Local Floodway). An example of a domain table is shown in Table L-3. 


Table L-3. Sample Domain Table 
FLDWAY_LID FLOODWAY 
1000 FLOODWAY 
1010 COLORADO RIVER 
1020 FLOODWAY CONTAINED IN CHANNEL 
1030 FLOWAGE EASEMENT BOUNDARY 
1040 STATE ENCROACHMENT 
1050 AREA OF SPECIAL CONSIDERATION 

Field names that end with _LID in the draft DFIRM specification (e.g., FLDWAY_LID) link 
to a domain table. The _LID field contains an integer that matches a value in the first field of 
the corresponding domain table. The second field of the domain table provides a more 
descriptive attribute value. In the Preliminary or Final DFIRM database, the _LID field is 
replaced by the second field from the domain table (i.e., FLOODWAY). The attribute value 
stored in the Preliminary or Final DFIRM database is the descriptive attribute value, rather than 
an integer. The domain tables are not included in the Preliminary or Final DFIRM database. 
The Mapping Partner creating draft digital data and using domain tables to create the 
S_Fld_Haz_Ar table, will enter 1000 in that table as the FLDWAY_LID value. In this 
instance, 1000 stands for FLOODWAY. When the Preliminary or Final DFIRM database is 
created, the FLDWAY_LID field becomes FLOODWAY, and the record value of 1000 
becomes FLOODWAY. 

When creating the Preliminary or Final DFIRM database, the assigned Mapping Partner shall 
treat the water name lookup table (L_Wtr_Nm) in the draft DFIRM digital data table structure 
option as a domain table. The surface water feature names stored in the lookup table must be 
transferred to related fields in other tables. 

L.2 Preparation of Draft Digital Data 

L.2.1 General 

If the Mapping Partner that creates the draft study components also produces the Preliminary Flood 
Insurance Study (FIS) report and FIRM, that Mapping Partner does not need to produce separate 
digital FIS data for the draft study components. Instead, the Mapping Partner will typically be 
responsible for creating a Preliminary or Final DFIRM database as described in Volume 1, 
Subsection 1.4.6.6 of these Guidelines and in Section L.3. 

The main issues that the assigned Mapping Partner shall consider in the preparation of the digital 
data are: 

 Coordination; 

 Standards; 
 Horizontal and Vertical Control; 
 Data Structure; 
 Quality Control; 
 Deliverable Format; and 
 Metadata. 
The portability of the draft digital data is the primary consideration during the Project Scoping 
phase of a project. This is important because a variety of commercially available mapping 
and/or survey software packages with varying formats exist. FEMA applications that will use the 
Mapping Partners digitally prepared mapping and survey data must be considered when 
"collecting" the information. To ensure compatibility, the assigned Mapping Partner shall 
capture the mapping features into a defined schema. The assigned Mapping Partner shall arrange 
the draft digital data within the draft DFIRM data files in such a manner that features are 
separated into a GIS table structure or a CADD layer/level and attribute structure. This 
Appendix provides standard schema for a Mapping Partner to follow. 

In addition, the digital data must be capable of being translated into a common spatial data 
exchange format. Normally, the specific data format and structure will be coordinated with the 
Project Team during the Project Scoping Meeting or immediately afterwards by technical staff. 

A major aspect of GIS is horizontal and vertical position on the earth. Mapping data must be 
referenced to a standard coordinate system, employ a standard projection, and specify both the 
horizontal and the vertical datums used. These positional references are established prior to the 
field data collection and topographic mapping phase of the project. All planimetric and 
topographic features must be collected and referenced to this coordinate system and projection. 
See Appendix A of these Guidelines for a detailed discussion of aerial mapping and surveying 
specifications, which includes horizontal and vertical control for new mapping. Also see Appendix 
B of these Guidelines for a discussion of vertical datum selection and conversion. 

Considerations for transfer of digital data also must include the file structure of the data, the 
transfer medium, the export/import device and the operating systems of the host and receiving 
systems (e.g., MS Windows, NT, UNIX). 

L.2.2 Coordination 

The assigned Mapping Partner must coordinate with the FEMA Lead and other Project Team 
members before beginning a draft digital submittal. The coordination may occur during the Project 
Scoping Meeting (see Volume 1, Subsection 1.3.2 of these Guidelines) or during a separate 
meeting immediately afterward. This meeting should serve to coordinate the digital capture of the 
restudy data and facilitate the production of digitally generated FIRMs in a timely fashion. Data 


format is an important consideration to be discussed prior to data capture, as changing data format 
after the fact can be both time consuming and costly. 

For most Flood Map Projects, the assigned Mapping Partner shall sub mit to FEMA a sample of the 
digital files being prepared when approximately 10 percent of the project has been completed. 
This will enable FEMA or another Mapping Partner selected by FEMA to review and comment on 
the digital data files, and will enable the submitting Mapping Partner to implement any 
modifications, if required, to the digital capture procedures at an early production stage. 

A meeting between the Mapping Partner that produces the draft study components, FEMA, and the 
Mapping Partner that produces the Preliminary and Final DFIRM may be required at the interim 
submittal stage, for all parties to be familiar with any unique conditions in the data files. 

Before beginning work to produce draft digital data, the assigned Mapping Partner shall coordinate 
with FEMA to determine if public domain software has been developed, and is available, for 
whatever hardware platform is chosen by the Mapping Partner for the digital work. Software may 
be available to assist in GIS table creation, data capture, data coding, layer/level assignment, 
quality control, and plotting. 

L.2.2.1 Data Sources 

As specified in Volume 1, Section 1.3 of these Guidelines, a Mapping Partner must perform initial 
research to avoid duplication of effort during a Flood Map Project. This is especially critical for 
digitally prepared study/restudy components because data collection is expensive. The assigned 
Mapping Partner shall identify and use existing digital data whenever possible, while still meeting 
required specifications and quality of work. 

As part of the initial coordination effort, the Mapping Partner that produces the draft digital 
study/restudy components shall identify available digital data and obtain datasets and hardcopy 
plots as necessary for study/restudy areas. Potential sources of digital base map or floodplain 
boundary data may be State, county, or local government agencies responsible for GIS, planning 
agencies or real estate assessment agencies. Digital floodplain data also may be available from 
FEMA, if the area has been previously converted to digital format. Requirement for base maps are 
specified in Appendix K. 

If existing data are available and used by the Mapping Partner that produces the draft digital 
study/restudy components, that Mapping Partner shall restructure the data to conform to one of the 
digitizing specification options listed below. If specific arrangements are made with the FEMA 
Leadusually, either the FEMA Regional Project Officer or the Project Officer (PO) at FEMA 
Headquartersto use another data schema, the assigned Mapping Partner shall provide complete 
documentation of the spatial data structure and attribute tables. 

As part of data collection, coordination and submittal, the assigned Mapping Partner shall 
document the data sources, date of collection or digitizing, scale of digitizing, projections, 
coordinate systems, horizontal datum and vertical datum of all of the digital data used and 
submitted. For each data source used, the assigned Mapping Partner shall add a Source Citation 
entry to the DFIRM metadata file in the Lineage section under Data Quality. Within the metadata 
file, each data source is assigned a Source Citation Abbreviation as shown in Table L-4. 


Table L-4. Source Citation Abbreviations 
Source Citation Abbreviation Use 
BASE 
For all base map sources (includes digital orthophotography, 
roads, railroads, airports, hydrography, U.S. Public Land Survey 
System (PLSS), political, military, park, forest and other lands) 
FIRM For features extracted from the existing FIRM 
FHBM For features extracted from the existing Flood Hazard Boundary 
Map (FHBM) 
FBFM For features extracted from the existing Flood Boundary and 
Floodway Map (FBFM) 
LOMC For information derived from a Letter of Map Change (LOMC) 
FIS For information taken from a previously published FIS report, 
including Floodway Table and Flood Profiles 
STUDY For information developed for the current Flood Map Project 
TSDN 
For any information taken from the Technical Support Data 
Notebook (TSDN) (used for existing backup information in 
FEMAs archives not published on previous FIRM) 

Each source citation abbreviation for a distinct data source should be numbered (e.g., BASE1, 
BASE2, BASE3). All spatial tables in the standards below have a SOURCE_CIT field. This field 
should be populated with the Source Citation Abbreviation from the metadata file that applies to 
the related spatial feature. 

L.2.3 Standards 

Maps and spatial data used for flood hazard analyses, floodplain boundary delineations, and FIRM 
compilation must meet all requirements specified in these Guidelines. The assigned Mapping 
Partner shall obtain or create these materials and submit these materials to FEMA, and shall ensure 
that the accuracy of the data in the submitted files, at a minimum, meets or exceeds FEMAs base 
map and FIS mapping information standards. The requirements for the flood hazard analyses, 
floodplain boundary delineations, and the base map are detailed in Volume 1, Section 1.4, 
Appendix A, and Appendix K of these Guidelines, respectively. 

L.2.4 Horizontal and Vertical Control 

The preferred projection, coordinate system and horizontal datum for the DFIRM Database spatial 
data is the UTM projection and coordinate system and referenced to NAD 1983. The data may 
also be in a State Plane coordinate system and associated projection if there is a compelling reason 
(e.g., project base map is in State Plane coordinates). The assigned Mapping Partner shall obtain 
approval for variations from these two options from the FEMA Lead in advance. However, at a 
minimum, the assigned Mapping Partner shall create all digital data in a system that is capable of 
referencing the data to a geographic coordinate system and projection. See Appendix K of these 
Guidelines for information on raster base maps in other projections and coordinate systems. 


In the event that the county or other jurisdiction being mapped lies in more than one projection and 
coordinate system zone, the assigned Mapping Partner shall ensure that all digital data submitted 
are projected in the zone that contains the largest portion of the jurisdiction in a single zone. The 
assigned Mapping Partner shall not use multiple State Plane or UTM zones within a single 
submittal. The assigned Mapping Partner may compile data in another zone, particularly if this 
facilitates higher positional accuracy of the data, reproject the data to the chosen zone for the 
jurisdiction being mapped, and merge the reprojected data with the rest of the data. 

The assigned Mapping Partner shall compile all horizontal information on either the North 
American Datum of 1927 (NAD27) (Clarke 1866 ellipsoid) or North American Datum of 1983 
(NAD83) (Geodetic Reference System 1980 --GRS 80 ellipsoid or revisions thereof). However, it 
is critical that horizontal datums not be mixed within a Flood Map Project. See Appendix A of 
these Guidelines for details on horizontal datum requirements. 

The assigned Mapping Partner shall reference all vertical information to either the National 
Geodetic Vertical Datum of 1929 (NGVD29) or the North American Vertical Datum of 1988 
(NAVD88). However, the Mapping Partner must not mix vertical datums within a Flood Map 
Project. See Appendix B of these Guidelines for details. 

L.2.5 Digital Data Structure 

Digital files must be prepared using a pre-defined system or schema that has been consistently used 
throughout. The layer/level or attribute assigned to a spatial element must be consistent and the 
information accessible to all users. The data must be organized in one of the data structures 
described in this Appendix and provided in one of the acceptable data formats unless specific 
arrangements are made with the FEMA PO. 

L.2.5.1 Tiling 

FEMA requires that all digital data be in one single file or a series of thematic files that cover the 
entire geographic area being mapped instead of individual small tiles that cover limited 
geographic areas. The assigned Mapping Partner shall obtain approval for any variations to this 
requirement from the FEMA Lead. 

L.2.5.2 Topology 

The assigned Mapping Partner shall ensure that vector data files must meet the following data 
structure requirements: 

 Digitized linework must be collected at a reasonably fine line weight. 
 Only simple linestrings or simple linear elements may be used for all linework. 
 Line features must be continuous (no dashes, dots, patterns, or hatching). 
 CADD files (e.g., MicroStation DGN files or AutoCAD DWG files) must not contain 
curves, B-splines, arcs or nested cells. 

 CADD files must not contain annotation generated from a database; the annotation must 
be placed as text. GIS files (e.g. ESRI coverages or ESRI Shape files) may contain 
annotation and/or database attributes. 
 Vectors may not cross other vectors within the same theme and all intersecting vectors 
must end at intersections. 
 Area spatial features for a given theme must cover the entire study area without overlaps, 
under laps or sliver polygons between adjacent polygons. 
 Files must be free of discontinuities such as overlapping lines, gaps, "turn backs," dangling 
lines and duplicate elements. 
 Spatial files must not contain any linear or area patterns. 
 Gaps or overshoots between features that should close must be eliminated. 
Logical consistency describes certain node-line-area relationships internal to the digital data. The 
Node-line-area relationship requirements that the assigned Mapping Partner must meet include 
the following: 

 Areas will be represented by closed polygons, without overshoots or undershoots. 
 Unattributed polygons are not permitted, including sliver polygons that result from 
poor digitizing methods. 
 Unnecessary nodes and vertices must be avoided. 
 Vertices must be placed conservatively when designing features so that only the minimal 
number of vertices or nodes is used to create the desired shape with appropriate 
smoothness (e.g., a straight line will be defined with two nodes only). 
 Lines must begin and end at nodes. 
 Lines must connect to each other at nodes. 
 Lines must not extend through nodes. 
L.2.5.3 Edgematching 

The matching of features along the edge of a hardcopy map or tiles of digital data is critical in 
the creation of digital map products. Proper edgematching will ensure that a digital map product 
can be used as a seamless data layer in a GIS. As edges are digitized, features that cross the edge 
should snap together to form a seamless feature. 

The assigned Mapping Partner shall ensure that all submitted digital data is tied into any existing 
digital data files so that a seamless transition is effected. The assigned Mapping Partner may 
produce new digital data to reflect new flood hazard information or to convert effective flood 


hazard information to digital format depending on the scope of the Flood Map Project. Hardcopy 
deliverables must reflect both the new digital data and any existing digital data previously prepared 
by FEMA. If no existing digital floodplain data are available from FEMA, deliverables must 
reflect the new digital data only. The assigned Mapping Partner must ensure that proper 
edgematching is performed at each step of the data creation process. If the Mapping Partner 
digitizes separate hardcopy sheets to produce the draft DFIRM data, the Mapping Partner must 
check that all features that cross the boundaries between separate sheets are smooth and continuous 
at the sheet boundaries. Likewise, the Mapping Partner must check that all features crossing 
jurisdiction boundaries are smooth and continuous at the jurisdiction boundary and that all features 
at the boundary of the draft DFIRM digital data submitted matches the contiguous information on 
the existing published FIRMs. 

 The following are edgematching problems that the assigned Mapping Partner must avoid: 
 Disconnects: Disconnects occur when the linework for features does not connect, either 
by being too short or too long at the source maps edge. 
 Jogs: Jogs occur when a common feature on adjoining maps does not line up seamlessly. 
 Missing Features: Missing features are those that appear on one source map, but not on 
the adjacent map. The features may be missing from one map because of a variety of 
reasons, such as (1) different dates of the two maps; (2) an error in one map; (3) a 
difference in interpretation by the cartographers of the two maps; (4) differing scales of 
the two source maps, or (5) adjacent data not available. 
 Different Representation of Features: Different representation of features occurs when 
features are represented differently on the source maps. For example, a road is a double 
line on one, and a single line on the other. 
L.2.5.4 Coincident Features 

Coincident features are those that share the same location or boundary, such as a flood zone 
boundary and a floodwall. These coincident features must superimpose, vertex (shape point) for 
vertex, within the files. If not automated properly, it could appear that the flood zone ends before 
the wall, leaving a strip of land on the waterside of the floodwall that is not in the flood zone. A 
lack of alignment can cause problems with digital files. 

For a new DFIRM, the assigned Mapping Partner shall create coincident features by digitizing 
the graphic features only once. The assigned Mapping Partner shall create additional copies of 
coincident features by copying part of the first feature to create the relevant portion of the 
second, when necessary. This will ensure that the lines match perfectly. 

In particular, the following pairs of tables have both area features and line features: 
S_Fld_Haz_Ln/S_Fld_Haz_Ar, S_Pol_Ln/S_Pol_Ar, and S_PLSS_Ln/S_PLSS_Ar. For these 
feature datasets, two tables are defined because they have attributes that apply to the entire area 
and attributes that apply to portions of the boundaries of these areas. However, the spatial 
elements that make up these features must be identical. All elements in the S_Fld_Haz_Ln table 


must match exactly with the boundaries of the elements in the S_Fld_Haz_Ar table. The same is 
true for the other two pairs of tables. For draft DFIRM digital data submitted in a spatial data 
format that supports both area and line attributes for the same spatial file, the assigned Mapping 
Partner shall submit a single spatial file with both sets of attributes. 

L.2.5.5 Precise Features 

The position of horizontal control features of the DFIRM products will be based on published 
standards. The assigned Mapping Partner shall not re-digitize these control features, but rather 
the assigned Mapping Partner shall use the exact coordinates in the published standards. 
Candidate sources of control points include: 

 U.S. Geological Survey 7.5-minute series quadrangle map corner coordinates; 
 Coordinate grid; and 
 Bench mark coordinates from the National Geodetic Survey or local control network. 
L.2.5.6 Data Compilation 

Existing digital data may affect the choice of scale for data compilation. If base mapping is 
available at a scale greater than 1" = 400' (e.g. 1" = 200') the assigned Mapping Partner may 
choose to compile and digitize the revised data developed during the Flood Map Project at the base 
map scale. 

FEMAs goal is to develop digital data that are as accurate as possible. In general, the most 
accurate data source must be relied upon to reference other features compiled onto the map. This 
may mean that, in some circumstances, floodplain boundary delineations made on very high-
resolution topographic maps may appear slightly misplaced on a less accurate base map. However, 
if the base map meets FEMA standards, these differences should be very small. If application of 
this approach creates significant visual problems with the floodplain boundary delineations on the 
base map selected, the assigned Mapping Partner shall resolve the issue with the FEMA Lead. 

Likewise, when high accuracy data are collected for a Flood Map Project, it is FEMAs goal to 
maintain the accuracy of those data. For example, cross-section line features must correspond as 
closely as possible to the actual field survey locations. Often, the assigned Mapping Partner must 
graphically extend or reshape that end of a cross section for satisfactory cartographic display. 
When this is necessary, the Mapping Partner shall perform it as a graphic operation for hardcopy 
map production. The Mapping Partner shall not modify the digital spatial data that depict the true 
locations of the surveyed cross sections. 

L.2.5.7 Digitizing 

All features must be digitized in their true positions as line strings or simple linear elements. 
Digitizing must be performed from stable base materials. 


How well the registration control points line up to the map to be digitized is an important 
measurement when digitizing maps. The measurement of fit is sometimes called the Root Mean 
Square Error (RMSE). The RMSE value represents the amount of error between original and 
new coordinate locations calculated by the transformation process. The lower the RMSE, the 
better the fit. The RMSE must be no more than 0.003 inch. 

L.2.5.8 Relationship of Base Map to Flood Hazard Data 

Base map features are physical features like roads, railroads, rivers, lakes, levees, and bench 
marks, that map users may rely on to locate an area of interest on the FIRM. Flood hazard data 
are flood insurance risk zones, Base Flood Elevations (BFEs), cross-section locations, and 
hydraulic structures that depict the results of flood hazard analyses on the FIRM. Some physical 
features such as surface water features and hydraulic structures are used in the performance of 
the flood hazard analysis and may be grouped in either category. 

The purpose of the base map is to present an accurate depiction of the relationship between the 
results of the flood hazard analyses and the physical features on the ground. Floodplain 
boundaries are typically delineated on a topographic map and may be subsequently transferred to 
the base map. The topographic and base map data may be derived from the same sources. The 
spatial accuracy of both the topographic and the digital base map is critical to maintaining the 
accuracy of the floodplain delineations. 

The digital base map for a Flood Map Project is to be identified during the Project Scoping 
phase of the project. The assigned Mapping Partner shall use the digital base map in conjuction 
with the topographic data when preparing the floodplain boundary delinations. For a complete 
discussion of base maps, see Volume 1, Subsection 1.4.3.1 of these Guidelines. 

Table L-5 presents the features for the base map. 

Table L-5. Base Map Data Tables 
Base Map Tables 
L_Wtr_Nm 
S_Base_Index 
S_Gen_Struct 
S_Label_Ld 
S_Label_Pt 
S_Perm_Bmk 
S_PLSS_Ar 
S_PLSS_Ln 
S_Pol_Ar 
S_Pol_Ln 
S_Quad_Index 
S_Trnsport_Ln 
S_Wtr_Ar 
S_Wtr_Ln 


For base map files, layers/levels or attributes are provided below for each data structure option. 
The Mapping Partner should insure that all Draft DFIRM Data files conform to the specifications 
below. An exception to this is preexisting base map files for PLSS, transportation and water 
features, which may retain their normal structure. More detail is provided in the table descriptions 
below. The standard table formats included below should be used when new base map data 
creation is included in the Mapping Partner scope of work. If any data from the Mapping Partner 
are not in one of the structures below, the data must be separated by layers/levels or by attributes. 
If the base map data are not structured following one of the data schema listed below, detailed 
documentation of the data structure must be included. 

The files produced by the Mapping Partner that creates draft digital study/restudy components shall 
typically cover only the area that is revised as a result of the Flood Map Project. 

L.2.5.9 Computer Assisted Drafting and Design or Geographic Information 
System Preparation 

A GIS database normally contains both spatial features and attribute records in the same file or in 
tables that can be easily related by the GIS system. A CADD system usually does not manage 
attribute records associated with each spatial feature as easily. As software evolves, there is less 
distinction between the two technologies. Users of these two systems still tend to apply these 
technologies in the traditional way. As a result, it is assumed that fundamentally different 
approaches will be used based on whether the Mapping Partner submits draft DFIRM data in 
CADD or GIS format. FEMA prefers to have DFIRM data submitted in GIS format. The CADD 
option is available for Mapping Partners who are unable to submit data in GIS format. 

Mapping Partners that submit digital data in GIS format shall separate the spatial data into 
individual tables or files for each data theme created (e.g., roads are stored in a separate file from 
flood zones that are in a separate file from political boundaries). The Mapping Partner may store 
attribute data in the same GIS file as the associated spatial features, in a parallel table structure in 
an RDBMS, or in individual data files in a standard database or spreadsheet format. When the 
attribute data is stored in a separate file from the spatial data, both the spatial data and the attribute 
data must have the same primary key field. 

Mapping Partners that submit data in CADD format shall store the spatial data in a single file with 
each data theme stored on a separate layer/level and identified by a color number within the file. 
See Subsection L.2.5.11 for detailed specifications. Each spatial feature in the CADD file must be 
attributed or tagged with a primary key that can be linked to the DFIRM attribute data for that 
feature. The Mapping Partner may store attribute data in the DFIRM table structure in an RDBMS 
or in individual data files in a standard database or spreadsheet format. Attribute data must be 
linked to the spatial features by the primary key for each table. Both the spatial data and the 
attribute data must have the same primary key field. 

L.2.5.10 Table Structure 

Each DFIRM database table has a primary key field defined. This field is normally the table 
name followed by _ID. The Mapping Partner that creates the digital data must populate these 


fields. Normally, the assigned Mapping Partner shall number the features in each table 
sequentially using this field; however, the assigned Mapping Partner may choose another method 
provided that the method is logical, documented, consistently implemented, and results in a 
unique ID value for each spatial feature. 

Regardless of whether the draft DFIRM digital data is submitted in CADD or GIS format, the 
assigned Mapping Partner must submit all of the applicable DFIRM database attribute tables. 
Attribute data must be linked to the spatial features by the primary key for each table. Both the 
spatial data and the attribute data must have the same primary key field. The Mapping Partner may 
choose to follow either the table structure defined in Section L.4 for draft digital data, or the table 
structure in Section L.7 for Preliminary and Final DFIRM databases. Regardless of the table 
structure selected, the Mapping Partner shall ensure that the applicable fields use the appropriate 
values from the associated domain tables and that these values are treated consistently across all 
tables. 

Which components of the DFIRM database that are required will depend on whether new flood 
analyses are part of the map update project as well as the judgement of the FEMA Regional 
Office. In general, the production of any digital map will result in a complete Standard DFIRM 
Database. However, most studies will also have some data in the Enhanced DFIRM Database. 
Even studies where existing effective flood hazard analyses are used to produce updated digital 
maps may capture easily accessible elements of the Enahanced DFIRM Database. In general, 
where new flood hazard analyses are performed, most of the core elements of the Enhanced 
Database described below will be populated. For each digital map update undertaken, the 
Mapping Partner should coordinate with the FEMA Regional Lead to determine how much of 
the Enhanced DFIRM Database should be completed. 

In the detailed table documentation in Sections L.4 and L.7, each field name is followed by a 
letter code as follows: 

 R  Required for all records. 

 A  Required if applicable to the described spatial feature. 

Plus, each field has a second code: 

 S  A component of the Standard DFIRM Database 

 E  A component of the Enhanced DFIRM Database 

See Section L.4 for specific requirements for each table for draft digital data submittal. 


For required fields, Null values are not permitted. In the event that the correct information cannot 
be obtained for a required field, the Project Officer may allow the mapping partner to substitute a 
value that indicates that the affected field was intentionally not populated. Any use of not 
populated values must be documented and explained in the metadata. The value to use for not 
populated data for each field type is as follows: 

 Character  NP 

 Numeric  -8888 

 Date  88880808 

 True.False  U 

For a field that is required when applicable, but does not apply, the value must be Null (i.e. the 
field must be left empty, not set to zero). The Mapping Partner shall use the value zero only when 
an attribute has the specific value of zero. Because of limitations in some of the GIS formats used 
by FEMA, a true Null value can not be used for some fields. The value to use for Null fields for 
each field type is as follows: 

 Character  Null (or , the empty string) 

 Numeric  -9999 

 Date  99990909 

 True.False  Null (or , the empty string) 

Text fields must follow the capitalization standards that apply to the display of that information on 
the FIRM. 

Date fields in the DFIRM database are stored in the native date format for the data format in 
which table is distributed. Not all of the database formats used for the DFIRM database support 
date values in the same way. The time of day is not stored or is set to zero depending on the 
structure of the date object in a particular data format. Where possible the output format of the 
date is set to YYYYMMDD. 

True/False fields in the DFIRM database are stored as text fields with a field size of one. Since 
different database programs store the authentic true/false fields in various ways, storing the 
true/false data as text helps eliminate inconsistencies between programs. For each true/false field 
in the DFIRM database, the user should enter T for true or F for false. 


L.2.5.11 Spatial Files for Computer Assisted Drafting and Design Format 

Mapping Partners that submit data in CADD format shall use the layer/level schema shown in 
Table L-6. No additional feature categories may be added to any layer/level. This ensures that 
data will not be miscoded in later processing steps or that time will not be spent separating 
features. To include feature categories that are not specified in the schema below (e.g., watersheds 
and sub-basins, land use classifications, building footprints), the Mapping Partner shall submit a 
second file containing these features and documentation of the layer/level schema. 

The main purpose of this schema is to provide a logical separation of data themes by layer/level 
and color. The assigned Mapping Partner shall name each layer/level following the convention 
provided in Table L-6. The color numbers in the following schema are also important. The 
layer/level and color number are used to separate feature types. The actual color used is not 
important for the digital file. It is important that the correct color number is used. The correct 
colors, line weights, and other cartographic details for a particular feature on the finished FIRM are 
specified in Appendix K of these Guidelines. Depending on the software used to create the draft 
DFIRM digital data, the Mapping Partner that creates the Preliminary or Final DFIRM may be able 
to provide file templates and other tools to facilitate reproduction of the graphic specifications. 
Coordination should take place between the Mapping Partners and FEMA shortly after the Project 
Scoping Meeting. The layer/level and color requirements for CADD submittals of draft digital 
data are presented in Table L-6. See Appendix K for more detailed descriptions of these features 
and the Glossary for acronym definitions. 


Table L-6. Layer/Level Schema Requirements 
DESCRIPTION 
LEVEL 
NUMBER LEVEL NAME COLOR 
Flooding Elements 
Floodway Boundary 1 floodway 
Colorado River Floodway 1 floodway 
Area of Special Consideration 1 floodway 
1% Flood Boundary 2 100-year 
0.2% Flood Boundary 3 500-year 
1%/0.2% Flood Boundary 4 100_500-year 
1% Flood/Floodway Boundary 5 100_fldway 
1%/0.2%/Floodway Boundary 6 100_500_fldway 
Zone D Boundary 7 zoned 
Zone Break 8 zonebreak 
Limit of Floodway 9 limitfldway 
Limit of Study 10 limitstudy 
Limit of Detailed Study 11 lods 
End of Spatial Extent 12 endspatial 
BFE 13 bfe 
Cross Section 14 xs_transect 
Transect 14 xs_transect 
Interpolated BFE 15 intbfe_intrxs 
Intermediate Cross Section 15 intbfe_intrxs 
Apparent Limit 16 applimit 
Floodway Shape/Hatch 17 shapefldway 
1% Flood Hazard Shapes 18 shape100 
0.2% Flood Hazard Shapes 19 shape500 
BFE Text 20 bfetxt 
Cross Section Hexagon 21 xsectxt 
Limit of Flooding Text 22 limittxt 
Zone Text 23 zonetxt 
Flowage Easement Line 24 flowage 
State Encroachment Line 24 flowage 
Hydro Elements 
Perennial River/Stream 25 hydro 30 
Intermittent River/Stream 25 hydro 31 
Shoreline/Coastline 25 hydro 32 
Lake 25 hydro 33 
Surface Water 25 hydro 34 
Reservoir 25 hydro 35 
Profile Baseline 25 hydro 36 
Swamp 25 hydro 37 
Channel 25 hydro 38 
Channel Contains 1% Flood 25 hydro 39 
Channel Contains 0.2% Flood 25 hydro 40 
Ditch 25 hydro 41 
Glacier 25 hydro 42 


Hatchery 25 hydro 43 
Race 25 hydro 44 
Wash 25 hydro 45 
Waterfall 25 hydro 46 
Water Separation Line 25 hydro 47 
Bog 25 hydro 48 
Retention Pond 25 hydro 49 
Tailings Pond 25 hydro 50 
PBL 25 hydro 51 
Water Feature Text 26 draintxt 52 
Landform/Island Text 27 islandtxt 53 
1000 Foot Marker & Text 28 rivermk 54 
River Mile Marker & Text 28 rivermk 55 
Structure Elements 
Weir 29 weir_dam 60 
Dam 29 weir_dam 61 
Levee 30 levee 62 
Culvert 31 culvert 63 
Culvert Contains 1% Flood 31 culvert 64 
Culvert Contains 0.2% Flood 31 culvert 65 
Headwalls/Wing walls 31 culvert 66 
Bridges 32 bridge 67 
Footbridge 32 bridge 68 
Pier 33 other_struct 69 
Dock 33 other_struct 70 
Jetty 33 other_struct 71 
Aqueduct 33 other_struct 72 
Dike 33 other_struct 73 
Fish Ladder 33 other_struct 74 
Flume 33 other_struct 75 
Gate 33 other_struct 76 
Lock 33 other_struct 77 
Penstock 33 other_struct 78 
Seawall 33 other_struct 79 
Structure Text 34 structxt 80 
Cobra/OPA Elements 
Cobra Boundary 35 cobra 90 
Otherwise Protected Areas 36 opa 91 
Cobra Shapes 37 shapecobra 92 
OPA Shapes 38 shapeopa 93 
Cobra/OPA Notes 39 cobratxt 94 
Political Elements 
Corporate Limits 40 corporate 100 
Extraterritorial Boundary 40 corporate 101 
Area Not Included 40 corporate 102 
County Boundary 41 county 103 
State Boundary 42 state_intl 104 


International Boundary 42 state_intl 105 
Political Boundary Text 43 polbdtxt 106 
City/Borough/Township Name 44 polareatxt 107 
Park Boundary 45 park 108 
Forest Boundary 45 park 109 
Reservation Boundary 45 park 110 
Park/Forest/Reservation Text 46 parktxt 111 
Urban Growth Boundary 47 other_juris 112 
MUD Boundary 47 other_juris 113 
LID Boundary 47 other_juris 114 
Transportation Elements 
Primary Roads 48 majorrds 120 
Secondary Roads 49 minorrds 121 
Trail 50 other_rds 122 
Undefined Roads 50 other_rds 123 
Road Tunnel 50 other_rds 124 
Ford 50 other_rds 125 
Road Text 51 roadtxt 126 
Route & Highway Symbols 51 roadtxt 127 
Railroad 52 railroad 128 
Abandoned Railroad 52 railroad 129 
Undefined Railroad 52 railroad 130 
Dismantled Railroad 52 railroad 131 
Railroad Tunnel 52 railroad 132 
Railroad Text 53 rrtxt 133 
Airport/Landing Strip & Text 54 airport 134 
Ferry 54 airport 135 
Grid Elements 
FIRM Neatline 55 map_neatlines 140 
Quad Neatline 55 map_neatlines 141 
Quarter Section Lines 56 plss 142 
Range Lines 56 plss 143 
Township Lines 56 plss 144 
Primary Grid & Labels 57 prigrid 145 
Secondary Grid & Labels 58 secgrid 146 
DOQ Neatline 63 nonplot 147 
Misc Elements 
NGS Bench Marks 59 ngs 150 
NGS Bench Mark Text 60 ngstxt 151 
Gaging Station 61 gaging 152 
Landmark 61 gaging 153 
Misc Text & Notes 62 misctxt 154 
LOMR Box 63 nonplot 155 
Non-Plotted Level 63 nonplot 200+ 


L.2.6 Quality Control 

Digital files must be structured according to one of the pre-established schemas. This allows easy 
exchange of data between FEMA and Mapping Partners. Files must be free of duplicated elements 
and complex linestrings. The data must be horizontally controlled and referenced to the 
appropriate horizontal and vertical datums. All digitizing must be done carefully and in 
conformance with FEMA accuracy standards. For these reasons, the assigned Mapping Partner 
shall perform a thorough quality control (QC) review prior to submitting data to FEMA. FEMA 
will review the data provided by the Mapping Partner using automated and interactive techniques. 

The following items must be included in the QC review of a verification plot to ensure that all 
deliverables meet minimum quality standards: 

 All required features have been included. 
 The data are correctly referenced to a State Plane or UTM grid coordinates. 
 The correct datum has been used and is clearly indicated. 
 All digitized linework is within 0.005 inch of its compiled location if digitizing is 
performed from a hardcopy manuscript. Plotted linework does not show gaps between 
plotted lines and compiled lines when plots and compilation manuscripts are overlaid. 
 Character of features has been maintained (e.g., straight lines are straight; curves are 
curved). 
 No obvious discontinuities exist (e.g., gaps, overshoots). 
 Required labels (text) have been placed. 
 All plotted data agree with the flood hazard analyses (e.g., regulatory floodway widths 
match) and cross-section labeling agrees with the appropriate computer model. 
 Deliverable plots meet the requirements specified in Subsection L.2.7 for deliverables. 
 Feature attributes are correct. 
 Pseudo-nodes or shape points have been kept to the minimum required to maintain the 
correct character of the features. 
L.2.7 Deliverables 

A complete draft DFIRM data submittal will include the following mapping items: 

 Digital base map files and DFIRM database files; 
 Digital Elevation Model (DEM) or Digital Terrain Model (DTM) if used; 

 Work maps (plots); 
 Map index; and 
 Metadata file as an ASCII text file. 
After completion of an internal QC review process, the Mapping Partner shall submit materials to 
FEMA in TSDN format. See Appendix M of these Guidelines for detailed requirements for the 
TSDN. 

L.2.7.1 Hardcopy Deliverables 

Each submittal must include hardcopy copies of the work maps. For details on the format and 
content for work maps, see Volume 1, Section 1.4 of these Guidelines. 

L.2.7.2 Digital Deliverables 

The digital data deliverables must clearly identify the data structure option that was used. To 
facilitate data processing, the assigned Mapping Partner shall submit Federal Geographic Data 
Committee (FGDC)-compliant metadata as specified in Subsection L.2.8. In addition, the 
Mapping Partner shall completely fill out the checklist presented in Section L.5 and include it with 
any digital data submitted to FEMA. If the Mapping Partners system output capabilities do not 
fall within these categories, the Mapping Partner shall obtain approval for an exception to these 
requirements before submitting digital files to FEMA for review. 


Raster Data 

Digital orthophoto files may be submitted in Tagged Image File Format (.TIF), Georeferenced 
TIF (GeoTIF), Band Interleaved by Pixel (.BIP or .BIL), Multi-Resolution Seamless Image 
Database (MrSID), Portable Network Graphics (PNG), or Joint Photographic Experts Group 
(JPEG) format. Raster files must be accompanied by a file that provides coordinate information 
that will allow the images to be georeferenced (e.g., a tfw file). 

Vector Data 

Mapping Partners may submit vector data in the following file formats: 

 ESRI export file  E00; 
 ESRI shape file  SHP; 
 MicroStation design file  DGN; 
 MapInfo interchange format  MIF; 
 MapInfo native table format  TAB; 
 AutoCAD drawing file  DWG; 
 Drawing exchange format  DXF; 
 Digital Line Graph  DLG; or 
 Spatial Data Transfer Standard  SDTS. 
Transfer Media 

Mapping Partners must submit files on one of the following electronic media: 

 CD-ROM (preferred); 
 Zip disk; 
 8mm tape; 
 3  diskette; 
 DVD; 
 Electronic transfer to File Transfer Protocol (FTP) site; or 
 Electronic transfer by E-mail (for files under 2 MB). 
As technology changes or in special situations, other media may be acceptable if coordinated 
with FEMA and the Mapping Partner receiving the data. 

If a file compression utility was used, provide the utility to uncompress the files. 


File Naming 

Wherever possible, the assigned Mapping Partner shall use the table names from the DFIRM 
database specifications as the file names for draft DFIRM data files with an extension appropriate 
to the file format. 

The draft DFIRM digital data files should be stored in a directory named for the state FIPS and 
county FIPS or CID and the term _DFIRM. Under each jurisdiction, there should be a separate 
directory for the standard DFIRM data files; a directory for raster base maps (orthophotos), if 
applicable; a directory for any enhanced DFIRM database information provided; a directory for 
raster images of the FIRM panels and their associated world files; a directory for the FIS report; 
and a directory for the metadata. Under the heading DFIRM_DB, all the files for each data 
format are stored together in a subdirectory named for the data format. For example, Montgomery 
County, Maryland, if submitted in ESRI Shapefile format would be stored as: 

\24031_DFIRM\DFIRM_DB\ArcShape\ -Directory contains all draft DFIRM data files in 
ESRI Shapefile format. 

\24031_DFIRM \Ortho_photos\ -Directory contains all raster base map data if used. 

\24031_DFIRM \Document\ -Directory containing metadata and a readme file. 

\24031_DFIRM \Enhanced_DB\ArcShape\ -Directory contains any enhanced DFIRM data 
files in ESRI Shapefile format. 

\24031_DFIRM \RFIRM\ -Directory contains any TIFF or PNG raster images of FIRM 
panels, the index and their associated world files. 

\24031_DFIRM \FIS\ -Directory contains PDF of the FIS report. 

Data Identification Requirements 

Complete documentation of file names, sizes, and contents is required. All digital media submitted 
must be labeled with at least the following information: 

 Mapping Partner name; 
 Community name and state for which the FIS was prepared; 
 The date the files were written to the media; 
 Details that are necessary to read the media. (e.g., submittals on 8mm tape should 
include the tape writing format, densit y and command syntax used); and 
 A brief description of contents. 
The digital media must clearly identify the data structure used. If any variation from these 
specifications is used, the assigned Mapping Partner shall submit a comprehensive list of the level 


or attribute structure of the affected data. This particularly applies to base map data, which may 
often be in a non-standard data structure. The Mapping Partner also shall provide thorough 
documentation for these files. 

L.2.8 Metadata 

To facilitate the use of these data and the transfer of data files between users, the assigned Mapping 
Partner shall prepare and submit a metadata file with all digital data submittals. Only one metadata 
file is required for each Flood Map Project, however, in this one file, the assigned Mapping Partner 
must distinguish between the different origins of the various datasets included. The Metadata file 
shall follow the Content Standard for Digital Geospatial Metadata (version 2.0), FGDC-STD-
001-1998. Details of this standard are available at www.fgdc.gov. A sample metadata file for 
draft digital data is presented in Section L.6. 

The metadata file must include a description of the source material from which the data were 
derived and the methods of derivation, including all transformations involved in producing the 
digital files. The description shall include the dates of the source material and the dates of ancillary 
information used for update. The date assigned to a source must reflect the date that the 
information corresponds to the ground. If the assigned Mapping Partner does not know this date, 
then the Mapping Partner may use the date of publication and indicate as such. Each data source in 
the metadata file must be assigned a Source Citation Abbreviation as described in Subsection 
L.2.2.1. 

The assigned Mapping Partner shall describe any database created by merging information 
obtained from distinct sources in sufficient detail to identify the actual source for each element in 
the file. 

Because not all DFIRM database tables are included in every draft DFIRM digital data submittal, 
the Overview Description Section of the Entity and Attribute Information of the metadata file must 
include a list of all DFIRM database tables included in the submittal. 

Wherever possible, the assigned Mapping Partner shall use the following metadata file naming 
convention. The file should be named with the combination of the two digit state FIPS code and 
Community or County Identification Number, followed by an _ and the effective date of the 
study (using the YYYYMMDD format), followed by _metadata and the approriate file 
extension (i.e., <ST_FIPS><PCOMM>_<EFF_DATE>_metadata.txt). The Community or 
County Identification Number is the 3rd through the 6th digits of the panel number. For community 
based maps this corresponds to the FEMA Community Identification number. For countywide 
maps this is the county (or county equivalent) FIPS code with a C . For studies that are 
Preliminary and not yet effective, the word PRELIM should be used instead of the effective date. 
For example, the name of a metadata file for an effective study would be similar to 
99001C_19980915_metadata.txt while the same file for a preliminary study could be 
99001C_PRELIM_metadata.txt. 

An example of a metadata file for draft DFIRM digital data is presented in Section L.6 of this 
Appendix. Portions of the file that are double underlined typically vary with each Mapping 


Partners submittal. In addition, the Mapping Partner should modify or replace any other portions 
of the metadata file to fully document the data submitted. 

L.3 Preparation of Preliminary and Final Digital Flood 
Insurance Rate Map Databases 

L.3.1 General 

FEMAs goal is to distribute consistent GIS versions of the flood hazard information for new 
DFIRMs. Therefore, Preliminary or Final DFIRM databases created by Mapping Partners must be 
consistent in file structure and in data format. The Mapping Partner that produces the draft 
DFIRM digital data must coordinate with the Mapping Partner that produces the Preliminary or 
Final DFIRM and the Preliminary or Final DFIRM database and ensure that the finished data meet 
applicable FEMA standards, include horizontal and vertical control, are documented properly, and 
conform with the standard data structure. The Mapping Partner that produces the Preliminary or 
Final DFIRM also must ensure that the Preliminary or Final DFIRM database meets FEMA 
specifications and that it is delivered to the FEMA Map Service Center in the proper formats. 

L.3.2 Coordination 

One of the responsibilities of the Mapping Partner that produces the Preliminary or Final DFIRM 
database is to ensure that the Preliminary or Final DFIRM database is consistent. The Mapping 
Partner that produces the Preliminary or Final DFIRM database must assist FEMA with 
coordination of the draft DFIRM digital data submittal. The coordination may occur as part of the 
Project Scoping Meeting or as a separate meeting immediately afterward. This meeting must serve 
to coordinate the digital capture of the data and to facilitate the production of a digitally generated 
FIRM in a timely fashion. Data format is an important consideration to be discussed before data 
capture, as changing the data format after the fact can be both time consuming and costly. 

The Mapping Partner that produces the draft DFIRM digital data shall submit to FEMA a sample 
of the digital files being prepared when the project is 10-percent complete. The Mapping Partner 
that produces the Preliminary or Final DFIRM database will assist FEMA to review the data files 
for any recommended modifications to digital capture procedures to be implemented by the 
Mapping Partner that produces the draft DFIRM digital data. 

L.3.2.1 Data Sources 

As specified in Volume 1, Section 1.3 of these Guidelines, initial research must be performed to 
avoid duplication of effort. This is especially critical for digitally prepared FIS because data 
capture is expensive. Existing digital data should be identified and used whenever possible, while 
still meeting required specifications and quality of work. 

It is recommended that as part of the initial coordination effort, the Mapping Partner that produces 
the draft digital study components identify available digital data and obtain data sets and hardcopy 
plots as necessary for restudy areas. If the Mapping Partner producing the Preliminary or Final 


DFIRM finds that data required for Preliminary or Final DFIRM database are missing, additional 
data research may be required. If the Mapping Partner that produces the draft DFIRM digital data 
is unable to supply the missing data, potential sources of digital base map or floodplain boundary 
data include state, county, or local government agencies responsible for GIS and planning or real 
estate assessment agencies. Digital floodplain data also may be available from FEMA, if the 
mapping for the area has been converted to digital format. 

If the Mapping Partner that produces the draft digital study components uses pre-existing data, the 
Mapping Partner shall restructure the data to conform to the spatial data and table structure 
requirements in Section L.7. 

As part of data collection, coordination and submittal, the Mapping Partner that produces the draft 
DFIRM digital data must document the data sources, date of collection or digitizing, scale of 
digitizing, projections, coordinate systems, horizontal datum, and vertical datum of all digital data 
used and submitted. For each data source used, the Mapping Partner sha ll add a Source Citation 
entry to the DFIRM metadata file in the Lineage section under Data Quality. Within the metadata 
file, the Mapping Partner shall assign each data source a Source Citation Abbreviation. These 
abbreviations are presented above in Subsection L.2.2.1 in Table L-4. 

The Mapping Partner that produces the draft DFIRM digital data shall number each source citation 
abbreviation for a distinct data source (e.g., BASE1, BASE2, BASE3). All spatial tables in the 
standards discussed in Subsection L.4 have a SOURCE_CIT field. The Mapping Partner that 
produces the draft DFIRM digital data shall populate the field with the Source Citation 
Abbreviation from the metadata file that applies to the related spatial feature. 

L.3.3 Standards 

The Mapping Partner shall ensure that the Preliminary or Final DFIRM database conforms with the 
standards listed in this Appendix and Volume 1 and Appendices A, B, K of these Guidelines, as 
applicable. 

L.3.4 Horizontal and Vertical Control 

The preferred projection, coordinate system and horizontal datum for the preliminary or final 
DFIRM Database spatial data is the UTM projection and coordinate system and referenced to 
NAD 1983. However, certain preliminary or final DFIRM Databases will be referenced to other 
projections and coordinate systems if the underlying base map data are orthophotos referenced to 
another projection and coordinate system. All digital data must be in a State Plane coordinate 
system and associated projection or the UTM projection and coordinate system. The Mapping 
Partner shall obtain approval from the FEMA Lead in advance for variations to these two options. 
See Appendix A of these Guidelines for a discussion of horizontal datum and Volume 1, 
Subsection 1.4.3.2 for a discussion of raster base maps in other projections and coordinate systems. 

In the event that the county or other jurisdiction being mapped lies in more than one UTM or State 
Plane Coordinate System zone, the assigned Mapping Partner must project all digital data 
submitted to the zone that contains the largest portion of the county or jurisdiction in a single zone. 


The assigned Mapping Partner shall not use multiple projection and coordinate system zones in the 
Preliminary or Final DFIRM database. 

All vertical information must reference either NGVD29 or NAVD88. The assigned Mapping 
Partner must not mix vertical datums within a submittal. See Appendix B of these Guidelines for 
details. 

L.3.5 Data Structure 

All Preliminary or Final DFIRM data must consistently follow the data structure described in 
Subsections L.7. 

L.3.5.1 Tiling 

The assigned Mapping Partner shall submit all digital data in a series of thematic files that cover 
the entire geographic area being mapped and not in individual small tiles that cover limited 
geographic areas. Preliminary or Final DFIRM databases should normally cover an entire 
county (or county equivalent). In situations where countywide mapping is not practical, the 
DFIRM database must cover an entire community or a subset of panels for a community or 
county. 

L.3.5.2 Topology 

Vector data files must meet the following data structure requirements: 

 Vectors may not cross other vectors within the same theme and all intersecting vectors 
must end at intersections. 
 Area spatial features for a given theme must cover the entire study area without overlaps, 
underlaps or sliver polygons between adjacent polygons. 
 Unnecessary nodes and vertices should be avoided. Vertices must be placed conservatively 
when designing freatures so that only the minimal number of vertices or nodes is used to 
create the desired shape with appropriate smoothness (e.g., a straight line will be defined 
with two nodes only). 
 Spatial files must not contain any linear or area patterns. 
 Gaps or overshoots between features that should close must be eliminated. 
Logical consistency describes certain node-line-area relationships internal to the digital data. 
Node-line-area relationship requirements include the following: 

 Areas must be represented by closed polygons, without overshoots or undershoots. 
 Uncoded polygons are not permitted, including sliver polygons that result from poor 
digitizing methods. 

 Unnecessary nodes and vertices must be avoided. Vertices must be placed conservatively 
when designing features so that only the minimal number of vertices or nodes is used to 
create the desired shape with appropriate smoothness (e.g. a straight line will be defined 
with two nodes only). 
 Lines must begin and end at nodes. 
 Lines must connect to each other at nodes. 
 Lines must not extend through nodes. 
L.3.5.3 Edgematching 

Preliminary or Final DFIRM databases must meet the edgematching requirements described 
above in Subsection L.2.5.3. 

L.3.5.4 Coincident Features 

Preliminary or Final DFIRM databases must meet the coincident feature requirements described 
above in Subsection L.2.5.4. 

L.3.5.5 Precise Features 

Preliminary or Final DFIRM databases must meet the precise feature requirements described 
above in Subsection L.2.5.5. 

L.3.5.6 Data Compilation 

FEMAs goal is to develop digital data that are as accurate as possible. In general, the most 
accurate data source must be relied upon to reference other features compiled onto the map. This 
may mean that, in limited circumstances, floodplain boundary delineations made on very high-
resolution topographic maps may appear slightly misplaced on a less accurate base map. However, 
if the base map meets FEMA standards, these differences should be very small. If this policy 
creates significant visual problems with the floodplain boundary delineations on the base map 
selected, the Mapping Partner shall resolve the issue with the FEM A Lead. 

Likewise, when high-accuracy data are collected for a Flood Map Project, it is FEMAs goal to 
maintain the accuracy of those data. For example, cross-section line features must correspond as 
closely as possible to the actual field survey locations. Often, the Mapping Partner must 
graphically extend or reshape that end of a cross section for satisfactory cartographic display. 
When this is necessary, it must be performed as a graphic operation for hardcopy map production. 
The Mapping Partner will not modify the digital spatial data that depict the true locations of the 
surveyed cross sections. 


L.3.5.7 Digitizing 

Preliminary or Final DFIRM databases must meet the digitizing requirements described above in 
Subsection L.2.5.7. 

L.3.5.8 Relationship of Base Map to Flood Hazard Data 

Base map features are physical features like roads, railroads, rivers, lakes, levees, political 
boundaries, and bench marks, that map users may rely on to locate an area of interest on the 
FIRM. Flood hazard data are flood insurance risk zones, BFEs, cross-section locations, and 
hydraulic structures that depict the results of flood hazard analyses on FIRM. Some physical 
features such as surface water features and hydraulic structures are used while performing the 
flood hazard analyses and may be grouped in either category. 

The purpose of the base map is to present an accurate depiction of the results of the flood hazard 
analyses in relation to the physical features on the ground. The floodplain boundaries are 
typically delineated on a topographic map and may be subsequently transferred to the base map. 
The topographic and base map data may be derived from the same sources. The spatial accuracy 
of both the topographic and digital base map is critical to maintaining the accuracy of the 
floodplain delineations. 

Table L-7 presents the features of the base map. 

Table L-7. Base Map Data Tables 
Base Map Tables 
L_Wtr_Nm 
S_Gen_Struct 
S_Label_Ld 
S_Label_Pt 
S_Perm_Bmk 
S_PLSS_Ar 
S_PLSS_Ln 
S_Pol_Ar 
S_Pol_Ln 
S_Quad_Index 
S_Trnsport_Ln 
S_Wtr_Ar 
S_Wtr_Ln 

The assigned Mapping Partner must ensure that all DFIRM database files conform to the required 
specifications with the exception of the base map files for PLSS, transportation and water features. 
If pre-existing data are used by the Mapping Partner for S_PLSS_Ar, S_PLSS_Ln, S_Trnsport_Ln, 
S_Wtr_Ar or S_Wtr_Ln, it is not necessary to restructure the files to meet the schema listed. This 
is discussed in more detail in the description of each of the tables in Section L.7. The data, 


however, must be structured logically. If the base map data are not structured following the 
standard data structure, the Mapping Partner must ensure that the tables that vary are documented 
in the Entity and Attribute section of the metadata file. 

L.3.5.9 Computer Assisted Drafting and Design or Geographic Information 
System Preparation 

Preliminary or Final DFIRM databases must be produced in the standard GIS formats listed below. 
If the Draft DFIRM data were submitted as CADD format data, it is the responsibility of the 
Mapping Partner that produces the Preliminary or Final DFIRM data to convert the data to GIS 
format. 

L.3.5.10 Table Structure 

Mapping Partners must follow the attribute table structure presented in Section L.7. The 
attribute data must be stored directly in the ESRI Shapefile, ESRI Export File, or MapInfo 
Interchange Format table along with the associated spatial data. The attribute data must not be in 
an independent data file or relational database format. Lookup tables must be stored in dbf 
format, info format, or MIF format. 

L.3.5.11 Spatial Files 

Mapping Partners must follow the table structure presented in Section L.7. All tables that begin 
with S_ are spatial files. 

Which components of the DFIRM database that are required will depend on whether new flood 
analyses are part of the map update project as well as the judgement of the FEMA Regional 
Office. In general, the production of any digital map will result in a complete Standard DFIRM 
Database. However, most studies will also have some data in the Enhanced DFIRM Database. 
Even studies where existing effective flood hazard analyses are used to produce updated digital 
maps may capture easily accessible elements of the Enahanced DFIRM Database. In general, 
where new flood hazard analyses are performed, most of the core elements of the Enhanced 
Database described below will be populated. For each digital map update undertaken, the 
Mapping Partner should coordinate with the FEMA Regional Office to determine how much of 
the Enhanced DFIRM Database should be completed. 

Each DFIRM database table has a primary key field defined. This field is normally the table 
name followed by _ID. The Mapping Partner that creates the digital data must populate these 
fields. Normally features in each table will be numbered sequentially using this field, although 
the Mapping Partner may choose another method provided it is logical, documented, consistently 
implemented, and results in a unique ID value for each spatial feature. 

In the table documentation in Section L.7, each field name is followed by a letter code as 
follows: 

 R  Required for all records 

 A  Required if applicable to spatial feature described 
Plus, each field has a second code: 
 S  A component of the Standard DFIRM Database 
 E  A component of the Enhanced DFIRM Database 
For required fields, Null values are not permitted. In the event that the correct information cannot 
be obtained for a required field, the Project Officer may allow the mapping partner to substitute a 
value that indicates that the affected field was intentionally not populated. Any use of not 
populated values must be documented and explained in the metadata. The value to use for not 
populated data for each field type is as follows: 

 Character  NP 
 Numeric  -8888 
 Date  88880808 
 True.False  U 
For a field that is required when applicable, but does not apply, the value must be Null (i.e. the 
field must be left empty, not set to zero). The Mapping Partner shall use the value zero only when 
an attribute has the specific value of zero. Because of limitatio ns in some of the GIS formats used 
by FEMA, a true Null value can not be used for some fields. The value to use for Null fields for 
each field type is as follows: 

 Character  Null (or , the empty string) 
 Numeric  -9999 
 Date  99990909 
 True.False  Null (or , the empty string) 
Text fields must follow the capitalization standards that apply to the display of that information on 
the FIRM. 

Date fields in the DFIRM database are stored in the native date format for the data format in 
which table is distributed. Not all of the database formats used for the DFIRM database support 
date values in the same way. The time of day is not stored or is set to zero depending on the 
structure of the date object in a particular data format. Where possible the output format of the 
date is set to YYYYMMDD. 

True/False fields in the DFIRM database are stored as text fields with a field size of one. Since 
different database programs store the authentic true/false fields in various ways, storing the 


true/false data as text helps eliminate inconsistencies between programs. For each true/false field 
in the DFIRM database, the user should enter T for true or F for false. 

L.3.6 Quality Control 

The digital files must be structured following the standard DFIRM database schema. This allows 
easy exchange of these data between FEMA, Mapping Partners, and other flood hazard data users. 
All duplicated elements must be removed. The data must be horizontally controlled and referenced 
to the appropriate horizontal and vertical datum. All digitizing must be done carefully and in 
conformance with FEMAs accuracy standards. The assigned Mapping Partner must perform a 
thorough QC review before submitting data to FEMA. FEMA will review the data provided by the 
Mapping Partner using automated and interactive techniques. 

The Mapping Partner must provide hardcopies of the Preliminary or Final effective DFIRM along 
with the DFIRM database for quality control review. 

L.3.7 Deliverables 

A complete DFIRM database submittal will be comprised of the following items: 

 Federal Emergency Management Agency Digital Mapping Information Checklist (refer to 
Section L.5 for detailed information); 
 Digital base map files and DFIRM database files in ESRI Shapefile, ESRI Export File, and 
MapInfo Interchange Format; 
 Metadata file as an ASCII text file; and 
 PDF version of the FIS report with bookmarks for the section heading and profiles. 
L.3.7.1 Hardcopy Deliverables 

The Mapping Partner must provide a transmittal form with the DFIRM database. The transmittal 
form shall document the scope of the submittal, including the files submitted, jurisdictions covered, 
etc. 

L.3.7.2 Digital Deliverables 

The digital submittal from the Mapping Partner to FEMA must include the complete DFIRM 
database in ESRI Shapefile, ESRI Export File, and MapInfo Interchange Format. The submittal 
also must include the metadata file, a readme text file, a raster version of each FIRM panel, and a 
PDF version of the FIS report. 

When a Mapping Partner produces the Preliminary DFIRM database, only ESRI Export File 
format and a metadata file is required for the initial QA/QC evaluation. 


Transfer Media 

The Mapping Partner must submit files to FEMA on one of the following electronic media: 

 CD-ROM (preferred); or 
 Electronic transfer to File Transfer Protocol (FTP) site. 
As technology changes or in special situations, other media may be acceptable, but must be 
approved by the FEMA Lead. 

File Naming 

To name DFIRM Database files, the Mapping Partner must use the table names listed in Section 
L.7 as the file name with an extension appropriate to the file format. 

The draft DFIRM digital data files should be stored in a directory named for the state FIPS and 
county FIPS or CID and the term _DFIRM. Under each jurisdiction, there should be a separate 
directory for the standard DFIRM data files; a directory for raster base maps (orthophotos), if 
applicable; a directory for any enhanced DFIRM database information provided; a directory for 
raster images of the FIRM panels and their associated world files; a directory for the FIS report; 
and a directory for the metadata. Under the heading DFIRM_DB, all the files for each data 
format are stored together in a subdirectory named for the data format. For example, Montgomery 
County, Maryland, if submitted in ESRI Shapefile format would be stored as: 

\24031_DFIRM\DFIRM_DB\ArcExport\ -Directory contains all draft DFIRM data files in 
ESRI Export format. 

\24031_DFIRM\DFIRM_DB\ArcShape\ -Directory contains all draft DFIRM data files in 
ESRI Shapefile format. 

\24031_DFIRM\DFIRM_DB\MapInfo\ -Directory contains all draft DFIRM data files in 
MapInfo MIF format. 

\24031_DFIRM \Ortho_photos\ -Directory contains all raster base map data if used. 

\24031_DFIRM \Document\ -Directory containing metadata and a readme file. 

\24031_DFIRM \Enhanced_DB\ArcExport\ -Directory contains any enhanced DFIRM 
data files in ESRI Export format. 

\24031_DFIRM \Enhanced_DB\ArcShape\ -Directory contains any enhanced DFIRM data 
files in ESRI Shapefile format. 

\24031_DFIRM \Enhanced_DB\MapInfo\ -Directory contains any enhanced DFIRM data 
files in MapInfo MIF format. 

\24031_DFIRM \RFIRM\ -Directory contains any TIFF or PNG raster images of FIRM 
panels, the index and their associated world files. 


\24031_DFIRM \FIS\ -Directory contains PDF of the FIS report. 

Data Identification Requirements 

Complete documentation of file names, sizes, and contents is required. The Mapping Partner shall 
label all digital media submitted to FEMA with at least the following information: 

 Mapping Partner name; 
 Community name and state affected by the Flood Map Project; 
 Preliminary date or effective date of the DFIRM database; and 
 Brief description of contents. 
L.3.8 Metadata 

To facilitate the use of these data and the transfer of data files between users, a metadata file shall 
accompany all digital data submittals. Only one metadata file is required for each Flood Map 
Project. However, in this file, the assigned Mapping Partner must distinguish between the different 
origins of the various datasets included. The metadata file shall follow the Content Standard for 
Digital Geospatial Metadata (version 2.0), FGDC-STD-001-1998. Details of this standard are 
available at www.fgdc.gov. A sample metadata file for Preliminary and Final DFIRM databases 
is presented in Section L.8 of this Appendix. 

This metadata file must include a description of the source material from which the data were 
derived and the methods of derivation, including all transformations involved in producing the 
final digital files. The description must include the dates of the source material and the dates of 
ancillary information used for update. The date assigned to a source must reflect the date that the 
information corresponds to the ground. If the Mapping Partner does not know this date, the 
Mapping Partner may use the date of publication and indicate as such. For each data source in the 
metadata file, the Mapping Partner shall assign a Source Citation Abbreviation as described under 
Data Sources in Subsection L.2.2.1. 

The Mapping Partner shall describe any database created by merging information obtained from 
distinct sources in sufficient detail to identify the actual source for each element in the file. 

Because not all DFIRM Database tables are included in every standard DFIRM database, the 
Overview Description Section of the Entity and Attribute Information should include a list of all 
DFIRM Database tables included in the submittal. 

Wherever possible, the assigned Mapping Partner shall use the following metadata file naming 
convention. The file should be named with the combination of the two digit state FIPS code and 
Community or County Identification Number, followed by an _ and the effective date of the 
study (using the YYYYMMDD format), followed by _metadata and the approriate file 
extension (i.e., <ST_FIPS><PCOMM>_<EFF_DATE>_metadata.txt). The Community or 
County Identification Number is the 3rd through the 6th digits of the panel number. For community 


based maps this corresponds to the FEMA Community Identification number. For countywide 
maps this is the county (or county equivalent) FIPS code with a C. For studies that are 
Preliminary and not yet effective, the word PRELIM should be used instead of the effective date. 
For example, the name of a metadata file for an effective study would be similar to 
99001C_19980915_metadata.txt while the same file for a preliminary study could be 
99001C_PRELIM_metadata.txt. 

An example of a metadata file for a DFIRM database is presented in Section L.8. Portions of the 
file that are double underlined typically vary with each DFIRM Database. In addition, the 
Mapping Partner must take care to modify or replace other portions of the metadata file to fully 
document the DFIRM database. 


L.4 Database Table Structure Requirements for Draft Digital 
Data 

Table: S_Base_Index 

This table is required if a raster base map was used as the base map for the Flood Insurance Rate 
Map (FIRM). 

The S_Base_Index table contains information about the raster data used as a base map for the 
study area. A spatial file with locational information also corresponds with this data table. 

The spatial elements representing raster base map tile index features are rectangular polygons. 
For standard U.S. Geological Survey Digital Orthophoto Quadrangles, polygons should match 
quarter-quad boundaries (excluding overedge). Otherwise, polygons should match the 
boundaries of the raster tiles used (excluding overedge if present). 

This is a Standard DFIRM Database table. 

The S_Base_Index table contains the following elements. 

BASE_ID R S Primary key for table lookup. Assigned by table creator. 

FILENAME R S Base Filename. This filename should be assigned by either the 
raster base map provider or the table creator. The filename should 
match the filename or specific product identifier assigned by the 
primary distributor of the raster base map used. This should be the 
complete filename including the file extension. This identifier must 
allow the user of the DFIRM database to unambiguously identify 
the raster base maps used on the FIRM to the primary distributor of 
the raster base map. 

BASE_DATE R S Base Date. This is the date that raster base map was acquired by 
the producer of the base map. For a vector base map that is 
rasterized for distribution, this data should be the acquisition date 
for the original vector base map. 

SOURCE_CIT R S Source Citation. Abbreviation used in the metadata file when 
describing the source information for the S_Base_Index table. 


Table: S_Base_Index

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
BASE_ID R S text 11 string 11 character 11 11 character 11 
FILENAME R S text 50 string 50 character 50 50 character 50 
BASE_DATE R S date/time 8 yyyymmdd 00/00/0000 date date 8 10 date 
SOURCE_CIT R S text 11 string 11 character 11 11 character 11 

L-57


Table: S_BFE 

The Base Flood Elevation (BFE) table is required for any digital data where BFE lines will be 
shown on the corresponding Flood Insurance Rate Map (FIRM). Normally, if there are any 
riverine AE zones, BFE lines are required. 

The S_BFE table contains information about the BFEs within a study area. A spatial file with 
locational information also corresponds with this data table. BFE lines indicate the rounded 
whole-foot water-surface elevation of the 1-percent-annual-chance flood. 

The spatial elements representing BFE features are lines extending from Special Flood Hazard 
Area (SFHA) boundary to SFHA boundary. The BFE lines will have no visible gaps or 
overshoots between the SFHA boundary and the end of the BFE line at the publication scale of 
the DFIRM. However, the ends of the BFE lines are not necessarily snapped precisely to the 
SFHA boundary. Each BFE is represented by a single line. While BFE lines are depicted as 
wavy lines on the hardcopy FIRM, they should be primarily straight lines in the spatial data, 
although they may bend consistent with procedures described in Volume 1 of these Guidelines. 

This is a Standard DFIRM Database table. 

The S_BFE table contains the following elements: 

BFE_LN_ID R S Primary key for table lookup. Assigned by table creator. 

ELEV R S Base Flood Elevation. The rounded, whole foot elevation of the 1-
percent-annual-chance flood. This is the value of the BFE that is 
printed next to the BFE line on the FIRM. 

LEN_LID R S Length Unit Lookup Identification. A code that provides a link to a 
valid unit of length measurement from the D_Length_Units table. 
This unit indicates the measurement system used for the BFEs. 
Normally this would be feet. 

V_DATM_LID R S Vertical Datum Lookup Identification. A code that provides a link 
to a valid vertical datum from the D_V_Datum table. The vertical 
datum indicates the reference surface from which the flood 
elevations are measured. Normally this would be North American 
Vertical Datum of 1988 for new studies. 

SOURCE_CIT R S Source Citation. Abbreviation used in the metadata file when 
describing the source information for the S_BFE table. 


Table: S_BFE

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
BFE_LN_ID R S text 11 string 11 character 11 11 character 11 
ELEV R S 
number 
(double) 8 2 number 13 2 numeric 8 13 2 decimal 15 2 
LEN_LID R S text 11 string 11 character 11 11 character 11 
V_DATM_LID R S text 11 string 11 character 11 11 character 11 
SOURCE_CIT R S text 11 string 11 character 11 11 character 11 

L-59


Table: S_CBRS 

This table is only required from Mapping Partners producing Preliminary and Final Digital Flood 
Insurance Rate Map (DFIRM) databases. This table only applies to coastal areas that have 
specially protected areas designated by Congress on John H. Chafee Coastal Barrier Resources 
System (CBRS) maps. Authoritative CBRS boundary locations are shown on these maps 
administered by the U.S. Fish and Wildlife Service. Normally these areas are already shown on 
existing Federal Emergency Management Agency (FEMA) Flood Insurance Rate Maps (FIRMs) 
for the area. CBRS areas have restrictions Federal funding (including flood insurance coverage) 
after specified dates for new or substantially improved structures. See Section 2.2 and Appendix 
K of these Guidelines for more detailed information about CBRS areas. 

The S_CBRS table contains information about the CBRS areas within the study area, if 
applicable. A spatial file with locational information also corresponds with this data table. 

The spatial elements representing CBRS features are closed polygons. Each contiguous CBRS 
area of the same CBRS_TYP and same CBRS_DATE should be a single polygon. 

This is a Standard DFIRM Database table. 

The S_CBRS table contains the following elements. 

CBRS_ID R S Primary key for table lookup. Assigned by table creator. 

CBRS_LID A S CBRS Lookup Identification. A code that provides a link to a valid 
CBRS type codes found in the D_CBRS_Typ table. The type code 
provides details of the types of prohibitions that apply to the area. 
Normally this would be CBRS area or an Otherwise Protected Area 
(OPA). This field is applicable if CBRS_TF is true. Otherwise this 
field is null. 

CBRS_DATE A S CBRS Date. Legislative or administrative date on which 
prohibitions for the CBRS area apply. This should be indicated on 
the FIRM with a note or with a fill pattern indicated on the legend. 
This field is applicable if CBRS_TF is true. Otherwise this field is 
null. 

CBRS_TF R S This field is True if the area is a CBRS or an OPA. Enter T for 
true or F for false. 

SOURCE_CIT R S Source Citation. Abbreviation used in the metadata file when 
describing the source information for the S_CBRS table. 


Table: S_CBRS

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
CBRS_ID R S text 11 string 11 character 11 11 character 11 
CBRS_LID A S text 11 string 11 character 11 11 character 11 
CBRS_DATE A S date/time 8 yyyymmdd 00/00/0000 date date 8 10 date 
CBRS_TF R S text 1 string 1 character 1 1 character 1 
SOURCE_CIT R S text 11 string 11 character 11 11 character 11 

L-61


Table: S_Cst_Gage 

This table is required when gage information is used to support the calibration of models or 
methods used in the analysis of coastal flood hazards and may be used in the determination of 
flood heights. 

The S_Cst_Gage table contains information about coastal gages for the study area. The spatial 
location of these gages may be some distance from the areas for which coastal flood hazards 
were determined. A spatial file with locational information also corresponds with this data 
table. 

The spatial elements representing the coastal gages are points. 

This is an Enhanced DFIRM Database table. 

The S_Cst_Gage table contains the following elements. 

GAGE_ID R E Primary key for table lookup. Assigned by table creator. 

CST_MDL_ID A E Coastal Model Identification. This field is populated by a linking 
element to the L_Cst_Model table. The L_Cst_Model table 
contains detailed information about the coastal models that were 
used to determine the coastal flood hazard for the area of each 
individual gage. This ID field should contain a number that 
matches the CST_MDL_ID field for a record in the L_Cst_Model. 
Multiple gages may link to a single record in the L_Cst_Model 
table. 

GAGE_NM R E Gage name assigned by agency maintaining gage. 

AGENCY R E Name of agency maintaining gage. 

REC_INTVL A E Recording Interval. This field is populated only if the coastal gage 
is a fixed-interval gage. 

TIME_LID A E Recording Interval Time Unit Lookup Identification. Link to 
D_Time_Units to establish unit of measure of the recording 
interval. This field is populated only if the coastal gage is a fixed-
interval gage. 

START_PD R E Gage Record Starting Date. Start of earliest period of record used 
in gage analysis. 

END_PD R E Gage Record Ending Date. End of latest period of record used in 
gage analysis. 


GAGE_LID R E Gage Type Lookup Identification. A code that provides a link to a 
valid entry from the D_Gage table. This value indicates the type of 
coastal gage. 

WVDIR_TF R E Does the gage record wave direction True or False? Enter "T" for 
true or "F" for false. 

WDSPD_TF R E Does the gage record wind speed True or False? Enter "T" for true 
or "F" for false. 

WDDIR_TF R E Does the gage record wind direction True or False? Enter "T" for 
true or "F" for false. 

SOURCE_CIT R E Source Citation. Abbreviation used in the metadata file when 
describing the source information for the S_Cst_Gage table. 


Table: S_Cst_Gage

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
GAGE_ID R E text 11 string 11 character 11 11 character 11 
CST_MDL_ID A E text 11 string 11 character 11 11 character 11 
GAGE_NM R E text 150 string 150 character 150 150 character 150 
AGENCY R E text 150 string 150 character 150 150 character 150 
REC_INTVL A E text 11 string 11 character 11 11 character 11 
TIME_LID A E text 11 string 11 character 11 11 character 11 
START_PD R E date/time 8 yyyymmdd 00/00/0000 date date 8 10 date 
END_PD R E date/time 8 yyyymmdd 00/00/0000 date date 8 10 date 
GAGE_LID R E text 11 string 11 character 11 11 character 11 
WVDIR_TF R E text 1 string 1 character 1 1 character 1 
WDSPD_TF R E text 1 string 1 character 1 1 character 1 
WDDIR_TF R E text 1 string 1 character 1 1 character 1 
SOURCE_CIT R E text 11 string 11 character 11 11 character 11 

L-64


Table: S_Cst_Tsct_Ln 

This table is required when the corresponding Flood Insurance Rate Map (FIRM) and/or Flood 
Insurance Study (FIS) will show coastal transect locations. Normally this is any area with a 
coastal study. 

The S_Cst_Tsct_Ln table contains information about the Coastal Transect Lines within the study area, if 
applicable. The transect lines indicate the location that was used to provide representative topographic 
information for the coastal flood models used. A spatial file with locational infor mation also corresponds 
with this data table. 

The spatial elements representing coastal transects are lines generally extending from offshore all 
the way across the coastal floodplain. Transects can also extend seaward when wave runup 
modeling is used into determining coastal flood hazards. Each transect should be represented by 
a single line feature without the circles on each end shown on the hard copy map. The location 
and shape of the lines should depict as accurately as possible the position of the transect used. 

This is a modified Standard DFIRM Database table that includes Standard DFIRM Database 
items and Enhanced Database items. All items after SOURCE_CIT are Enhanced. 

The S_Cst_Tsct_Ln table contains the following elements. 

TRAN_LN_ID R S Primary key for table lookup. Assigned by table creator. 

TRAN_NO R S Transect Number. Transect number as shown on FIRM or in FIS. 
Each transect is normally numbered sequentially. 

SOURCE_CIT R S Source Citation. Abbreviation used in the metadata file whe n 
describing the source information for the S_Cst_Tsct_Ln table. 

CST_MDL_ID A E Coastal Model Identification. This field is populated by a linking 
element to the L_Cst_Model table. The L_Cst_Model table 
contains detailed information about the coastal models that were 
used to determine the coastal flood hazard for the area of each 
individual transect line. This ID field should contain a number that 
matches the CST_MDL_ID field for a record in the L_Cst_Model. 
Multiple transects may link to a single record in the L_Cst_Model 
table. This field is not required for digital conversion of existing 
FISs. Significant additional research may be required to identify 
the model that applies for each transect. However, for new coastal 
studies, this field is required. 

SETUP_DPTH A E Wave Set-up Depth. This is the depth of wave setup that is added 
to the 1% annual chance stillwater elevation. 

SIG_HT A E Significant Wave Height. This is the wave height associated with 
the 1% annual chance storm event. It is the average height of the 


highest 1/3 of all waves. It is used in WHAFIS 3.0 and RUNUP 2.0 
models. 

SIG_PD A E Significant Wave Period. This is the wave period associated with 
the 1% annual chance storm event. It is the time it takes for a wave 
of the significant wave height to pass a point. 

CON_HT A E Controlling Wave Height. 1.6 times the significant wave height. 

CON_PD A E Controlling Wave Period. The time it takes for a wave of the 
controlling wave height to pass a point. 

MEAN_HT A E Mean Wave Height. Average height of all waves. This information 
is typically derived from wave gage data. 

MEAN_PD R E Mean Wave Period. Average period of all waves. This information 
is typically derived from wave gage data. 

EROS_LID A E Erosion Methodology Lookup Identification. A code that provides 
a link to a valid erosion methodology from the D_Eros_Method 
table. 

TIME_LID R E Units of Time Measurement Lookup Identification. A code that 
provides a link to valid time measurements from the D_Time_Units 
table. This field is populated if there is a value entered for the 
significant wave period, controlling wave period, or the mean wave 
period. The period values all should use the same unit of time 
measurement. 

V_DATM_LID R E Vertical Datum Lookup Identification. A code that provides a link 
to a valid datum from the D_V_Datum table. The vertical datum 
indicates the reference surface from which the elevations are 
measured. Normally this would be North American Vertical Datum 
of 1988 for new studies. 

LEN_LID R E Length Unit Lookup Identification. A code that provides a link to a 
valid unit of measurement from the D_Length_Units table. This 
unit indicates the measurement system used for the elevation, depth, 
height, and distance values. Normally this would be feet. 

VZONE_LID R E V Zone Extent Lookup Identification. A code that provides a link 
to a valid V Zone extent from the D_VZone table. This information 
provides a brief summary to users about the predominating 
methodology that was used to determine the landward extent of the 
V Zone in any mapped flood hazard area. 


METH_LID R E Source Method Lookup Identification. A code that provides a link 
to a valid source method from the D_Method table. This value 
describes the general methodology used in deriving the station and 
elevation point data along transects used in coastal flood hazards. 

EFF_TF R E Is the coastal transect part of the effective study True or False? 
Enter "T" for true or "F" for false. 

SHOWN_FIRM R E Transect Shown on FIRM. Is the transect shown on the FIRM True 
or False? Enter "T" for true or "F" for false. 

SHR_LID R E Shoreline Roughness Lookup Identification. A code that provides a 
link to a valid shoreline type from the D_Shr_Rough table. This 
value is the shoreline type classification that relates each transect 
with a shoreline type. This information can be used in conjunction 
with other coastal hazard analyses or applications and provides a 
useful set of data about relative shoreline roughness. 

L_RANGE R E Left Range of Coastal Transect. Looking landward, the range is the 
along-shore distance to the left of the transect line that the transect 
is intended to represent. 

L_DIRECT R E Direction of Left Range. Direction is entered as the bearing of the 
range away from the transect. The left range direction is measured 
in degrees and is the angle of an arc taken in a clockwise direction 
from north to the ranges bearing. If the transect is oriented 
perpendicular to the shoreline, this value will be +/-90 degrees of 
the transect's direction in degrees from north. 

R_RANGE R E Right Range of Coastal Transect. Looking landward, the range is 
the along-shore distance to the right of the transect line that the 
transect is intended to represent 

R_DIRECT R E Direction of Right Range. Direction is entered as the bearing of the 
range away from the transect. The right range direction is measured 
in degrees and is the angle of an arc taken in a clockwise direction 
from north to the ranges bearing. If the transect is oriented 
perpendicular to the shoreline, this value will be +/-90 degrees of 
the transect's in direction in degrees from north. 

LOC_DESC R E Location Description. This is a description of the location of the 
coastal transects. This description is used and/or can be found in 
the transect table in the FIS text. 


XCOORD R E X-Coordinate. The X-coordinate of the 0.0-foot elevation point 
along the transect. This point must fall on the transect and have the 
same horizontal datum of the study. The coordinates must be 
entered using the same coordinate system used for the DFIRM GIS 
data. If the S_Shore_Ln table is provided, the shoreline should cross 
the transect at this point. 

YCOORD R E Y-Coordinate. The Y-coordinate of the 0.0-foot elevation point 
along the transect. This point must fall on the transect and have the 
same horizontal datum of the study. The coordinates must be 
entered using the same coordinate system used for the DFIRM GIS 
data. If the S_Shore_Ln table is provided, the shoreline should 
cross the transect at this point. 

. 


Table: S_Cst_Tsct_Ln

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
Type 
field 
size dec format input mask type width Dec type 
item 
width 
output 
width dec type width dec 
TRAN_LN_ID R S Text 11 string 11 character 11 11 character 11 
TRAN_NO R S Text 4 string 4 character 4 4 character 4 
SOURCE_CIT R S Text 11 string 11 character 11 11 character 11 
CST_MDL_ID A E Text 11 string 11 character 11 11 character 11 
SETUP_DPTH A E 
number 
(double) 8 2 number 13 2 numeric 8 13 2 decimal 15 2 
SIG_HT A E 
number 
(double) 8 2 number 13 2 numeric 8 13 2 decimal 15 2 
SIG_PD A E 
number 
(double) 8 2 number 13 2 numeric 8 13 2 decimal 15 2 
CON_HT A E 
number 
(double) 8 2 number 13 2 numeric 8 13 2 decimal 15 2 
CON_PD A E 
number 
(double) 8 2 number 13 2 numeric 8 13 2 decimal 15 2 

L-69


MEAN_HT A E 
number 
(double) 8 2 number 13 2 numeric 8 13 2 decimal 15 2 
MEAN_PD R E 
number 
(double) 8 2 number 13 2 numeric 8 13 2 decimal 15 2 
EROS_LID A E Text 11 string 11 character 11 11 character 11 
TIME_LID R E Text 11 string 11 character 11 11 character 11 
V_DATM_LID R E Text 11 string 11 character 11 11 character 11 
LEN_LID R E Text 11 string 11 character 11 11 character 11 
VZONE_LID R E Text 11 string 11 character 11 11 character 11 
METH_LID R E Text 11 string 11 character 11 11 character 11 
EFF_TF R E Text 1 string 1 character 1 1 character 1 
SHOWN_FIRM R E Text 1 string 1 character 1 1 character 1 
SHR_LID R E Text 11 string 11 character 11 11 character 11 
L_RANGE R E 
number 
(double) 8 2 number 13 2 numeric 8 13 2 decimal 15 2 
L_DIRECT R E 
number 
(double) 8 2 number 13 2 numeric 8 13 2 decimal 15 2 
R_RANGE R E number 8 2 number 13 2 numeric 8 13 2 decimal 15 2 

L-70


(double) 
R_DIRECT R E 
number 
(double) 8 2 number 13 2 numeric 8 13 2 decimal 15 2 
LOC_DESC R E Text 254 string 254 character 254 254 character 254 
XCOORD R E 
number 
(double) 8 2 string 13 2 numeric 8 13 2 decimal 15 2 
YCOORD R E 
number 
(double) 8 2 string 13 2 numeric 8 13 2 decimal 15 2 

L-71


Table: S_FIRM_Pan 

This table is required for all draft Digital Flood Insurance Rate Map (DFIRM) data. 

The S_FIRM_Pan table contains information about the Flood Insurance Rate Map (FIRM) panel 
area. A spatial file with locational information also corresponds with this data table. 

The spatial entities representing FIRM panels are polygons. The polygon for the FIRM panel 
corresponds to the panel neatlines. As a result, the panels are generally rectangular. In situations 
where a portion of a panel lies outside of the jurisdiction being mapped, the user must refer to the 
S_POL_AR table to determine the portion of the panel area where the DFIRM database shows 
the effective flood hazard data for the mapped jurisdiction. 

This is a Standard DFIRM Database table. 

The S_FIRM_Pan table contains the following elements. 

FIRM_ID R S Primary key for table lookup. Assigned by table creator. 

ST_FIPS R S State FIPS. This is the two-digit code that corresponds to the State 
Federal Information Processing Standard (FIPS) code. This is a 
standard numbering system that is used by the Federal government. 
Defined in FIPS Pub 6-4. These two numbers correspond to the first 
two digits of the panel number. 

PCOMM R S Community or County Identification Number. This is the 3rd 
through the 6th digits of the panel number. For community based 
maps this corresponds to the Federal Emergency Management 
Agency (FEMA) Community Identification number. For 
countywide maps this is the county (or county equivalent) FIPS 
code with a C. 

PANEL R S Panel Number. This is 7th through the 10th digits in the complete 
panel number. This is assigned by the scale of the map and the 
position within either the community or county. The panel number 
scheme is described in detail in Appendix K of these Guidelines. 

SUFFIX R S Map Suffix. This is the final digit in the complete panel number. 
This is a letter suffix at the end of the panel number. 

FIRM_PAN R S FIRM Panel Number. This is the complete FIRM panel number, 
which is made up of ST_FIPS, PCOMM, PANEL, and SUFFIX. 
This is the 11-digit FIRM panel number that is shown in the title 
block of the map. 

PANEL_LID R S Panel Lookup Identification. A code that provides a link to the 
D_Panel_Typ table; this field will indicate if the maps are printed 


or not printed, community based, county wide, or an unmapped 
community. 

EFF_DATE A S Effective Date. This is the effective date of the current map 
revision. This field is not populated until the FIRM effective date is 
established and the Final FIRM is ready for hardcopy production by 
FEMA. Then it is required. 

SCALE_LID R S Map Scale Lookup Identification. A code that provides a link to a 
value in the D_Scale table, it is the denominator of the scale of the 
FIRM. 

PNP_REASON A S Panel Not Printed Reason. If the FIRM panel is not printed, this is 
the reason. This could include All Zone X or other reasons. See 
Appendix K for a listing of Panel Not Printed reasons that may be 
used. Only completed if the hardcopy panel is not printed by 
FEMA. 

NW_LAT R S Northwest Latitude. This is the latitude of the northwest corner of 
the FIRM panel neat line. This value is in degrees, minutes, 
seconds (DDD MM SS.SSS). Normally this corresponds to U.S. 
Geological Survey (USGS) 7.5 quadrangle maps using North 
American Datum of 1983 (NAD83), or even subdivisions thereof. 
However this value should reflect the actual latitude if non-standard 
panel sizes are used. 

NW_LONG R S Northwest Longitude. This is the longitude of the northwest corner 
of the FIRM panel. This value is in degrees, minutes, seconds 
(DDD MM SS.SSS). Normally this corresponds to USGS 7.5 
quadrangle maps using NAD83, or even subdivisions thereof. 
However this value should reflect the actual longitude if non-
standard panel sizes are used. 

SE_LAT R S Southeast Latitude. This is the latitude of the southeast corner of 
the FIRM panel. This value is in degrees, minutes, seconds (DDD 
MM SS.SSS). Normally this corresponds to USGS 7.5 quadrangle 
maps using NAD83, or even subdivisions thereof. However, this 
value should reflect the actual latitude if non-standard panel sizes 
are used. 

SE_LONG R S Southeast Longitude. This is the longitude of the southeast corner 
of the FIRM panel. This value is in degrees, minutes, seconds 
(DDD MM SS.SSS). Normally this corresponds to USGS 7.5 
quadrangle maps using NAD83, or even subdivisions thereof. 
However this value should reflect the actual longitude if non-
standard panel sizes are used. 


SOURCE_CIT R S Source Citation. Abbreviation used in the metadata file when 
describing the source information for the S_FIRM_Pan table. 


Table: S_FIRM_Pan

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
FIRM_ID R S text 11 string 11 character 11 11 character 11 
ST_FIPS R S text 2 string 2 character 2 2 character 2 
PCOMM R S text 4 string 4 character 4 4 character 4 
PANEL R S text 4 string 4 character 4 4 character 4 
SUFFIX R S text 1 string 1 character 1 1 character 1 
FIRM_PAN R S text 11 string 11 character 11 11 character 11 
PANEL_LID R S text 11 string 11 character 11 11 character 11 
EFF_DATE A S date/time 8 yyyymmdd 00/00/0000 date date 8 10 date 
SCALE_LID R S text 11 string 11 character 11 11 character 11 
PNP_REASON A S text 50 string 50 character 50 50 character 50 
NW_LAT R S text 15 string 15 character 15 15 character 15 
NW_LONG R S text 15 string 15 character 15 15 character 15 
SE_LAT R S text 15 string 15 character 15 15 character 15 
SE_LONG R S text 15 string 15 character 15 15 character 15 

L-75


SOURCE_CIT R S text 11 string 11 character 11 11 character 11 

L-76


Table: S_Fld_Haz_Ar 

This table is required for all draft Digital Flood Insurance Rate Map data. 

The S_Fld_Haz_Ar table contains information about the flood hazards within the study area. A 
spatial file with locational information also corresponds with this data table. These zones are 
used by the federal Emergency Management Agency (FEMA) to designate the Special Flood 
Hazard Area (SFHA) and for insurance rating purposes. These data are the flood hazard areas 
that are or will be depicted on the Flood Insurance Rate Map (FIRM). A spatial file with 
locational information also corresponds with this data table. 

The spatial elements representing the flood zones are polygons. The entire area of the 
jurisdiction(s) mapped by the FIRM should have a corresponding flood zone polygon. There is 
one polygon for each contiguous flood zone designated. 

This is a modified Standard DFIRM Database table that includes Standard DFIRM Database 
items and Enhanced Database items. All items after SOURCE_CIT are Enhanced. 

The S_Fld_Haz_Ar table contains the following elements. 

FLD_AR_ID R S Primary key for table lookup. Assigned by table creator. 

ZONE_LID R S Flood Zone Lookup Identification. This is a code that provides a 
link to a valid entry from the D_Zone table. This is the flood zone 
label/abbreviation for the area. 

FLDWAY_LID A S Floodway Lookup Identification. This is a code that provides a link 
to a valid entry from the D_Floodway table. Floodway areas are 
designated by FEMA and adopted by communities to provide an 
area that will remain free of development to moderate increases in 
flood heights due to encroachment on the floodplain. If the 
corresponding area is not designated as a floodway, this field is 
null. 

SFHA_TF R S Special Flood Hazard Area. If the area is within SFHA this field 
would be True. This field will be true for any area that is coded for 
any A or V zone flood areas. It should be false for any X or D zone 
flood areas. Enter T for true or F for false. 

STATIC_BFE A S Static Base Flood Elevation. For areas of constant Base Flood 
Elevation (BFE), the BFE value is shown beneath the zone label 
rather than on a BFE line. In this situation the same BFE applies to 
the entire polygon. This is normally occurs in lakes or coastal 
zones. This field is only populated where a static BFE is shown on 
the FIRM. 


V_DATM_LID A S Vertical Datum Lookup Identification. A code that provides a link 
to a valid vertical datum from the D_V_Datum table. The vertical 
datum indicates the reference surface from which the flood 
elevations are measured. Normally this would be North American 
Vertical Datum of 1988 for new studies. This field is only 
populated if the STATIC_BFE is populated. 

DEPTH A S Depth Value for Zone AO Areas. This is shown beneath the zone 
label on the FIRM. This field is only populated if a depth is shown 
on the FIRM. 

LEN_LID A S Length Unit Lookup Identification. A code that provides a link to a 
valid unit of length from the D_Length_Units table. This unit 
indicates the measurement system used for the BFEs and/or depths. 
Normally this would be feet. This field is only populated if the 
DEPTH or STATIC_BFE field is populated. 

VELOCITY A S Velocity Measurement. This is shown beneath the zone label on the 
FIRM for alluvial fan areas (certain Zone AO areas). This value 
represents the velocity of the flood flow in this area. This field is 
only populated when a velocity is shown on the FIRM. 

VEL_LID A S Velocity Unit Lookup Identification. A code that provides a link to 
a valid unit of velocity from the D_Vel_Units table. This unit 
indicates the measurement system for the velocity of the flood 
hazard area. The value is shown in the legend where alluvial fans 
are present. This field is only populated if the VELOCITY field is 
populated. 

AR_REVERT A S If the area is Zone AR, this field would hold the zone that the area 
would revert to if the AR zone were removed. This field is only 
populated if the corresponding area is Zone AR. Acceptable values 
for this field are listed in the D_Zone table. 

BFE_REVERT A S If Zone is Zone AR, this field would hold the static base flood 
elevation for the reverted zone. This field is populated when Zone 
equals AR and the reverted zone has a static BFE. 

DEP_REVERT A S If Zone is Zone AR, this field would hold that flood depth for the 
reverted zone. This field is populated when Zone equals AR and 
the reverted zone has a depth assigned. 

SOURCE_CIT R S Source Citation. Abbreviation used in the metadata file when 
describing the source information for the S_Fld_Haz_Ar table. 
Normally, the flood hazard area polygon will be divided to 
distinguish areas modified by the most recent revision from areas 
based on the effective FIRM prior to the most recent revision. 
Revisions and sources prior to the most recent revision will not be 


tracked for individual polygons in the flood hazard areas table in the 
standard database. 

HYDRO_ID A E Hydrologic Model Identification. A code that provides a link to the 
hydrologic model table, L_Hydro_Model. The L_Hydro_Model 
table provides information on the methods used to determine the 
flood hazard for areas of shallow flooding and ponding. This ID 
field must contain a number that matches the HYDRO_ID field for 
a record in the L_Hydro_Model table. This attribute is only 
required for flood hazard areas with AO and AH zone designations 
or ponding associated with AE zones. 

CST_MDL_ID A E Coastal Model Identification. This field is populated by a linking 
element to the L_Cst_Model table. The L_Cst_Model table 
contains detailed information about the coastal models that were 
used to determine the coastal flood hazard for this area. This ID 
field must contain a number that matches the CST_MDL_ID field 
for a record in the L_Cst_Model table that documents coastal model 
information. This attribute is only required in areas for which flood 
hazard determinations do not consider wave hazards. The static 
BFE values in these areas are based on surge modeling and/or tidal 
analyses. When wave hazards are considered modeling information 
is linked to the transects used to complete the wave analysis. 


Table: S_Fld_Haz_Ar

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
FLD_AR_ID R S text 11 string 11 character 11 11 character 11 
ZONE_LID R S text 11 string 11 character 11 11 character 11 
FLDWAY_LID A S text 11 string 11 character 11 11 character 11 
SFHA_TF R S text 1 string 1 character 1 1 character 1 
STATIC_BFE A S 
number 
(double) 8 2 number 13 2 numeric 8 13 2 decimal 15 2 
V_DATM_LID A S text 11 string 11 character 11 11 character 11 
DEPTH A S 
number 
(double) 8 2 number 13 2 numeric 8 13 2 decimal 15 2 
LEN_LID A S text 11 string 11 character 11 11 character 11 
VELOCITY A S 
number 
(double) 8 2 number 13 2 numeric 8 13 2 decimal 15 2 
VEL_LID A S text 11 string 11 character 11 11 character 11 
AR_REVERT A S text 6 string 6 character 6 6 character 6 

L-80


BFE_REVERT A S 
number 
(double) 
8 2 number 13 2 numeric 8 13 2 decimal 15 2 
DEP_REVERT A S 
number 
(double) 
8 2 number 13 2 numeric 8 13 2 decimal 15 2 
SOURCE_CIT R S text 11 string 11 character 11 11 character 11 
HYDRO_ID A E text 11 string 11 character 11 11 character 11 
CST_MDL_ID A E text 11 string 11 character 11 11 character 11 

L-81


Table: S_Fld_Haz_Ln 

This table is required for all draft Digital Flood Insurance Rate Map data. 

The S_Fld_Haz_Ln table contains information about the flood hazard line features for the study 
area. A spatial file with locational information also corresponds with this data table. 

The spatial elements representing the boundaries of the flood hazard areas depicted on the Flood 
Insurance Rate Map (FIRM) are lines. 

This is a Standard DFIRM Database table. 

The S_Fld_Haz_Ln table contains the following elements. 

FLD_LN_ID R S Primary key for table lookup. Assigned by table creator. 

LN_LID R S Line Lookup Identification. A code that provides a link to a valid 
entry from the D_Ln_Typ table. These line types describe the flood 
boundary and may be used to indicate how the feature should be 
depicted on the hardcopy FIRM. 


Table: S_Fld_Haz_Ln

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
FLD_LN_ID R S text 11 string 11 character 11 11 character 11 
LN_LID R S text 11 string 11 character 11 11 character 11 

L-83


Table: S_Gen_Struct 

This table is required whenever hydraulic structures are shown in the flood profile. It is also 
required if levees are shown on the FIRM, channels containing the flooding are shown on the 
FIRM, or any other structure that impacts the areas flood risk is shown on the FIRM. 

The S_Gen_Struct table contains information about the hydraulic structures within the study 
area. It should include all structures shown in the flood profiles. In addition, levees, sea walls, 
channels that contain flooding, and other significant flood control structures shown on the Flood 
Insurance Rate Map (FIRM) should be included. A spatial file with locational information also 
corresponds with this data table. 

Spatial elements representing general structures are represented by lines. The lines should 
represent the primary characteristic of the structure. For example, bridges should be represented 
by the transportation centerline carried by the bridge. Dams should be represented by a line 
corresponding to the top of the dam. Levees should be represented by a line corresponding to the 
top of levee. A line corresponding to the centerline of the main barrel should represent a culvert. 

This is a Standard DFIRM Database table. 

The S_Gen_Struct table contains the following elements. 

STRUCT_ID R S Primary key for table lookup. Assigned by table creator. 

STRUCT_LID R S Structure Type Lookup Identification. A code that provides a link 
to a valid entry from the D_Struct_Typ table. This table contains 
entries for most major types of structures that would be found in 
hydraulic analyses. 

STRUCT_NM A S Structure Name. This is the name of the feature and the name that 
will be shown on the hardcopy FIRM. This record is left blank if 
the structure is not named on FIRM and/or the name is unknown. 

WTR_NM_LID R S Surface Water Name Lookup Identification. A code that provides a 
link to the name of the surface water feature. The surface water 
feature name is taken from the table L_Wtr_Nm. This is a lookup 
table that is populated by the creator of the database. 

SOURCE_CIT R S Source Citation. Abbreviation used in the metadata file when 
describing the source information for the S_Gen_Struct table. 


Table: S_Gen_Struct

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
STRUCT_ID R S text 11 string 11 character 11 11 character 11 
STRUCT_LID R S text 11 string 11 character 11 11 character 11 
STRUCT_NM A S text 50 string 50 character 50 50 character 50 
WTR_NM_LID R S text 11 string 11 character 11 11 character 11 
SOURCE_CIT R S text 11 string 11 character 11 11 character 11 

L-85


Table: S_Label_Ld 

This table is required for Digital Flood Insurance Rate Map (DFIRM) data if any label leader 
lines are shown on the hardcopy FIRM. 

The S_Label_Ld table contains information about leader lines that would connect labels to 
feature locations on base maps. The purpose of this table, along with the S_Label_Pt table is so 
that the DFIRM database can contain the names of roads and other physical features in or near 
the Special Flood Hazard Areas regardless of the type or structure of the base map used. A 
spatial file with locational information also corresponds with this data table. 

The spatial entities representing label leaders will be lines. 

This is a Standard DFIRM Database table. 

The S_Label_Ld table contains the following elements. 

LEADER_ID R S Primary key for table lookup. Assigned by table creator. 

LABEL_LID R S Label Type Lookup Identification. A code that provides a link to 
valid entries from the D_Label_Typ table. This type is a description 
of the planimetric features to which the labels and leaders are 
associated. For vector based maps, the labels and leaders will be 
associated with vector features in S_Trnsport_Ln, S_Wtr_Ar and 
S_Wtr_Ln. For maps with an ortho-photo base, the labels and 
leaders will be associated with DOQ water and transportation 
features. For maps that use both vector features and ortho-photos, 
all values may apply. 


Table: S_Label_Ld

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
LEADER_ID R S text 11 string 11 character 11 11 character 11 
LABEL_LID R S text 11 string 11 character 11 11 character 11 

L-87


Table: S_Label_Pt 

This table is required for all draft Digital Flood Insurance Rate Map (DFIRM) data. 

The S_Label_Pt table contains information for text insertion point locations that would link 
labels to base map features. The purpose of this table, along with the S_Label_Ld table is so that 
the DFIRM database can contain the names of roads and other physical features in or near the 
Special Flood Hazard Areas (SFHAs) regardless of the type or structure of the base map used. A 
spatial file with locational information also corresponds with this data table. 

The spatial entities representing labels are points. The point corresponds to the lower left corner 
of the label. 

This is a Standard DFIRM Database table. 

The S_Label_Pt table contains the following elements. 

LABEL_ID R S Primary key for table lookup. Assigned by table creator. 

LABEL R S Label for map feature. 

LABEL_LID R S Label Type Lookup Identification. A code that provides a link to 
valid entries from the D_Label_Typ table. This type is a description 
of the planimetric features to which the labels and leaders are 
associated. For vector based maps, the labels and leaders will be 
associated with vector features in S_Trnsport_Ln, S_Wtr_Ar and 
S_Wtr_Ln. For maps with an ortho-photo base, the labels and 
leaders will be associated with DOQ water and transportation 
features. For maps that use both vector features and ortho-photos, 
all values may apply. 

DEGREES R S The degrees of rotation required for the placement of a feature label 
onto a hard copy Flood Insurance Rate Map panel. The rotation 
angle of the text measured in degrees. The angle is zero for 
unrotated horizontal text and increases in a counterclockwise 
direction to 359. Text rotated clockwise has a negative value 
between 0 and 359. 


Table: S_Label_Pt

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
LABEL_ID R S text 11 string 11 character 11 11 character 11 
LABEL R S text 254 string 254 character 254 254 character 254 
LABEL_LID R S text 11 string 11 character 11 11 character 11 
DEGREES R S integer 2 0 number 4 0 binary 4 10 0 decimal 4 0 

L-89


Table: S_LOMR 

This table is required when a Mapping Partner incorporates the results of effective Letters of 
Map Revision (LOMRs) into the draft Digital Flood Insurance Rate Map (DFIRM) data 
submitted to the Federal Emergency Management Agency (FEMA). 

The S_LOMR table contains information about LOMR areas that are incorporated into the Flood 
Insurance Rate Map (FIRM). This table is planned as a mechanism for DFIRM producers to 
communicate areas of the DFIRM data that were updated to reflect the results of LOMRs. It is included 
in the draft DFIRM data submittal. It is not planned for distribution by FEMA once a complete map 
revision has incorporated these LOMRs into the effective FIRM panel. Therefore it is not included in the 
Preliminary or Final DFIRM data. A spatial file with locational information also corresponds with this 
data table. 

The spatial entities representing LOMRs are polygons. The spatial information contains the 
bounding polygon for each LOMR area. 

This is a modified Standard DFIRM Database table that includes Standard DFIRM Database 
items and Enhanced Database items. All items after SOURCE_CIT are Enhanced. 

The S_LOMR table contains the following elements. 

LOMR_ID R S Primary key for table lookup. Assigned by table creator. 

EFF_DATE R S Effective Date. Effective Date of the LOMR. 

CASE_NO R S Case Number. This is the case number of the LOMR that is 
assigned by FEMA. The case number is used to track the LOMRs 
supporting documentation. 

SCALE_LID R S Map Scale. A code that provides a link to a value in the D_Scale 
table. The linked value will contain the denominator of the 
effective scale of the LOMR. 

SOURCE_CIT R S Source Citation. Abbreviation used in the metadata file when 
describing the source information for the S_LOMR table. 

STATUS R E Status of the LOMR. Valid entries for this field include the 
following: 

effective 

incorporated 

superseded 


Table: S_LOMR

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
LOMR_ID R S text 11 string 11 character 11 11 character 11 
EFF_DATE R S date/time 8 yyyymmdd 00/00/0000 date date 8 10 date 
CASE_NO R S text 13 string 13 character 13 13 character 13 
SCALE_LID R S text 11 string 11 character 11 11 character 11 
SOURCE_CIT R S text 11 string 11 character 11 11 character 11 
STATUS R E text 12 string 12 character 12 12 character 12 

L-91


Table: S_Nodes 

This table is required for all studies with new or revised hydrologic data. A spatial file with 
locational information also corresponds with this data table. 

The S_Nodes table contains data only on the location of points used to define the topology of the 
hydrologic network. Nodes can be subbasin pourpoints, confluences, diversions, hydraulic 
structures, etc. Nodes are connected to each other via links, which are defined in S_Profil_Basln 
(see below). 

The spatial elements representing the nodes are points. 
This is an Enhanced DFIRM Database table. 

The S_Nodes table contains the following elements. 

NODE_ID R E Primary key for this table. Assigned by table creator. 

SOURCE_CIT R E Source Citation. Abbreviation used in the metadata file when 
describing the source information for S_Nodes. 


Table: S_Nodes

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
NODE_ID R E text 11 string 11 character 11 11 character 11 
SOURCE_CIT R E text 11 string 11 character 11 11 character 11 

L-93


Table: S_Ovrbnkln 

This table is required for a detailed study that uses overbank flow lengths as input data. 

The S_Ovrbnkln table contains information about overbank flow line features for the study area. 

The features are those lines along which overbank flow distances between two cross sections are 
measured. Between any two adjacent cross sections, there must be two overbank flow lines: one 
for the right overbank line and one for the left overbank line. The two lines may be one 
continuous line or may be broken at the cross section. However, if the line is broken, the line 
must be continuous between the cross sections; the endpoints of an overbank line must lie on a 
cross section. A spatial file with locational information also corresponds with this data table. 

Since models will eventually overlap, these features should represent the lines associated with 
the model for the base flood from which the effective FIRM was derived. 

Locations are based on standard engineering practice and should match locations used in the 
analysis. 

The spatial elements representing the boundaries of the flood hazards depicted on the FIRM are 
lines. 

This is an Enhanced DFIRM Database table. 

The S_Ovrbnkln table contains the following elements. 

OVRBNK_ID R E Primary key for table lookup. Assigned by table creator. 

WTR_NM_LID R E Surface Water Name Lookup Identification. A code that provides a 
link to the name of the surface water feature. The surface water 
feature name is taken from the L_Wtr_Nm table. This is a lookup 
table that is populated by the creator of the database. 

OBNK_SIDE R E Overbank Side. Indicates which side the overbank line represents. 
Enter L for left or R for right. 

SOURCE_CIT R E Source Citation. Abbreviation used in the metadata file when 
describing the source information for the S_Ovrbnkln. 


Table: S_Ovrbnkln

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
OVRBNK_ID R E text 11 string 11 character 11 11 character 11 
WTR_NM_LID R E text 11 string 11 character 11 11 character 11 
OBNK_SIDE R E text 1 string 1 character 1 1 character 1 
SOURCE_CIT R E text 11 string 11 character 11 11 character 11 

L-95


Table: S_Perm_Bmk 

This table is required unless there are no National Geodetic Survey (NGS) or other bench marks 
that meet the minimum standard in the jurisdiction covered by the Flood Insurance Rate Map 
(FIRM). 

The S_Perm_Bmk table contains information about Permanent Bench Marks that are associated 
with the study area. The bench marks shown in this file must meet the requirements specified in 
Subsection 1.4.1.4.1 of these Guidelines. A spatial file with locational information also 
corresponds with this data table. 

The spatial entities representing bench marks are points. Generally, these points should be 
placed based on the coordinates in the NGS database. However, the horizontal coordinates 
maintained by the NGS for vertical bench marks are often not very precise because the users rely 
on the location descriptions to locate the bench marks. If the source of the horizontal coordinates 
used by the NGS is not precise, the data creator may adjust the position based on more accurate 
data. 

This is a Standard DFIRM Database table. 

The S_Perm_Bmk table contains the following eleme nts. 

BM_ID R S Primary key for table lookup. Assigned by table creator. 

PID R S Permanent Identifier. This should be the NGS assigned or 
community assigned permanent identifier. It must be unique for 
each bench mark. 

SOURCE_CIT R S Source Citation. Abbreviation used in the metadata file when 
describing the source information for the S_Perm_Bmk table. 


Table: S_Perm_Bmk

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
BM_ID R S text 11 string 11 character 11 11 character 11 
PID R S text 11 string 11 character 11 11 character 11 
SOURCE_CIT R S text 11 string 11 character 11 11 character 11 

L-97


Table: S_PFD_Ln 

This table is required when a primary frontal dune (PFD) is present along portions or all of the 
coastline within the modeled coastal floodplain. PFDs are not required to be continuous along 
the length of the studied shoreline. It is applicable when PFD_TF = T in the L_Cst_Model 
table. 

The S_PFD_Ln table contains information about the primary frontal dune features for the coastal 
study area. Primary frontal dunes are not shown on the FIRM but are used in the coastal 
floodplain analysis. They are lines that represent the back side of the first natural ridge inland 
from the coastal shoreline and where the gradient changes from steep to gentle. A spatial file 
with locational information also corresponds with this data table. 

The spatial elements representing the primary frontal dunes are lines. 

This is an Enhanced DFIRM Database table. 

The S_PFD_Ln table contains the following elements.
PFD_ID R E Primary key for table lookup. Assigned by table creator.

SOURCE_CIT R E Source Citation. Abbreviation used in the metadata file when 
describing the source information for the S_PFD_Ln table. 


Table: S_PFD_Ln

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
PFD_ID R E text 11 string 11 character 11 11 character 11 
SOURCE_CIT R E text 11 string 11 character 11 11 character 11 

L-99


Table: S_PLSS_Ar 

This table is required when U. S. Public Land Survey System (PLSS) areas are shown on the 
Flood Insurance Rate Map and the data used for the map can be distributed by FEMA at no cost. 

The S_PLSS_Ar table contains information about the PLSS areas that are associated within the 
study area. These include the attributes for the range, township, and section areas. A spatial file 
with locational information also corresponds with this data table. 

The spatial elements representing the PLSS areas are polygons. Generally there is one polygon 
per section. The PLSS areas should cover the entire jurisdiction where sections are defined. 

In general, the Public Land Survey System table structure is fairly flexible depending on the 
format of the data available for the map. The Federal Emergency Management Agencys 
(FEMAs) objective is to have spatially accurate PLSS data to which the flood hazard 
information is referenced. Users must be able to identify section, township and range 
information on the printed maps. If these objectives are met, then almost any file structure is 
acceptable. PLSS features may be represented as either polygons or lines. With some data 
structures, it may not be practical to assign attributes to each spatial entity. While these 
attributes are desirable, FEMA recognizes that they may not always be easily available. This is 
acceptable because the PLSS system is a public system not maintained by FEMA. This 
information is provided for reference on the paper maps.. 

This is a Standard DFIRM Database table. 

The S_PLSS_Ar table contains the following elements. 

PLSS_AR_ID R S Primary key for table lookup. Assigned by table creator. 

RANGE A S Range Number. This is the range number assigned to the PLSS 
area shown. This attribute would also include the designation of E 
(east) or W (west) as part of the data. For example, 21W would be 
an acceptable value. This field is applicable whenever the 
SECT_NO does not equal zero. 

TWP A S Township. This is the township number assigned to the PLSS area 
shown. This attribute would also include the designation of N 
(north) or S (south) as part of the data. For example, 14S would be 
an acceptable value. This field is applicable whenever the 
SECT_NO does not equal zero. 

SECT_NO R S Section. This is the section number assigned to the PLSS area 
shown. Where no section number is defined, such as open water, 
the section number should be zero. 

SOURCE_CIT R S Source Citation. Abbreviation used in the metadata file when 
describing the source information for the S_PLSS_Ar table. This 


field is required when source citation information is not provided 
by the S_PLSS_Ln table. 


Table: S_PLSS_Ar

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
PLSS_AR_ID R S text 11 string 11 character 11 11 character 11 
RANGE A S text 8 string 8 character 8 8 character 8 
TWP A S text 8 string 8 character 8 8 character 8 
SECT_NO R S text 4 string 4 character 4 4 character 4 
SOURCE_CIT R S text 11 string 11 character 11 11 character 11 

L-102


Table: S_PLSS_Ln 

This table is required when U.S. Public Land Survey System (PLSS) areas are shown on the 
Flood Insurance Rate Map (FIRM) and the data used for the map can be distributed by FEMA at 
no cost. 

The S_PLSS_Ln table contains information about the boundary lines for the PLSS that is 
associated with the study area, if applicable. This would include the attributes for the adjacent 
range and township areas. A spatial file with locational information also corresponds with this 
data table. 

In general, the Public Land Survey System table structure is fairly flexible depending on the 
format of the data available for the map. The Federal Emergency Management Agencys 
(FEMAs) objective is to have spatially accurate PLSS data to which the flood hazard 
information is referenced. Users must be able to identify section, township and range 
information on the printed maps. If these objectives are met, then almost any file structure is 
acceptable. PLSS features may be represented as either polygons or lines. With some data 
structures, it may not be practical to assign attributes to each spatial entity. While these 
attributes are desirable, FEMA recognizes that they may not always be easily available. This is 
acceptable because the PLSS system is a public system not maintained by FEMA. This 
information is provided for reference on the paper maps.. 

The spatial entities representing PLSS boundaries are lines. 

This is a Standard DFIRM Database table. 

The S_PLSS_Ln table contains the following elements. 

PLSS_LN_ID R S Primary key for table lookup. Assigned by table creator. 

LN_LID R S Line Lookup Identification. A code that provides a link to a valid 
entry from the D_Ln_Typ table. These line types describe the 
PLSS boundaries and may be used to indicate how the feature 
should be depicted on the hardcopy FIRM. 

E_RANGE A S East Range Number. This is the range number assigned to the 
PLSS area shown to the east of the line feature. This number is 
shown on the hardcopy FIRM. This attribute would also include 
the designation of E (east) or W (west) as part of the data. For 
example, 21W would be an acceptable value. Only populated for 
lines that divide one range from another. 

W_RANGE A S West Range Number. This is the range number assigned to the 
PLSS area shown to the west of the line feature. This number is 
shown on the hardcopy FIRM. This attribute would also include 
the designation of E (east) or W (west) as part of the data. For 


example, 21W would be an acceptable value. Only populated for 
lines that divide one range from another. 

N_TWP A S North Township. This is the township number assigned to the 
PLSS area shown to the north of the line feature. This number is 
shown on the hardcopy FIRM. This attribute would also include 
the designation of N (north) or S (south) as part of the data. For 
example, 14S would be an acceptable value. Only populated for 
lines that divide one township from another. 

S_TWP A S South Township. This is the township number assigned to the 
PLSS area shown to the south of the line feature. This number is 
shown on the hardcopy FIRM. This attribute would also include 
the designation of N (north) or S (south) as part of the data. For 
example, 14S would be an acceptable value. Only populated for 
lines that divide one township from another. 

SOURCE_CIT R S Source Citation. Abbreviation used in the metadata file when 
describing the source information for the S_PLSS_Ln table. This 
field is required when source citation information is not provided 
by the S_PLSS_Ar table. 


Table: S_PLSS_Ln

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
PLSS_LN_ID R S text 11 string 11 character 11 11 character 11 
LN_LID R S text 11 string 11 character 11 11 character 11 
E_RANGE A S text 8 string 8 character 8 8 character 8 
W_RANGE A S text 8 string 8 character 8 8 character 8 
N_TWP A S text 8 string 8 character 8 8 character 8 
S_TWP A S text 8 string 8 character 8 8 character 8 
SOURCE_CIT R S text 11 string 11 character 11 11 character 11 

L-105


Table: S_Pol_Ar 

This table is required for all draft Digital Flood Insurance Rate Map data. 

The S_Pol_Ar table contains information about the Political Areas within the study area. This 
includes the attributes for the political areas and other areas such as forests, parks, military lands, 
and Tribal lands. For the National Flood Insurance Program (NFIP), it is important to know the 
jurisdiction that has land use authority over an area. Political jurisdictions individually agree to 
participate in the NFIP and availability of insurance, floodplain regulations, and insurance rates 
may vary by political jurisdiction. The political jurisdiction assigned to each area corresponds to 
the jurisdiction responsible for NFIP and floodplain management for that area. A spatial file 
with locational information also corresponds with this data table. 

The spatial entities representing political areas are polygons. 

This is a Standard DFIRM Database table. 

The S_Pol_Ar table contains the following elements. 

POL_AR_ID R S Primary key for table lookup. Assigned by table creator. 

POL_NAME1 R S Political Area Name 1. This is the primary name of the area shown. 
For areas that have more than one name, this would be the primary 
name with subsequent names shown in fields below. This would 
correspond to the official name of this jurisdiction used by the 
Federal Emergency Management Agency (FEMA) within the NFIP. 
For unincorporated areas of a county, this should be the county 
name (e.g., Montgomery County). 

POL_NAME2 A S Political Area Name 2. This is the secondary name of the area 
shown. Populated if there is a common name for an area other than 
the official jurisdiction name. 

CO_FIPS R S County FIPS Code. This is the three-digit county Federal 
Information Processing Standard (FIPS) code. This is a standard 
numbering system that is used by the Federal government. Defined 
in FIPS Pub 6-4. 

ST_FIPS R S State FIPS. This is the two-digit code that corresponds to the state 
FIPS code. This is a standard numbering system that is used by the 
Federal government. Defined in FIPS Pub 6-4. These two numbers 
correspond to the first two digits of the panel number. 

COMM_NO R S Community Number. This is the four-digit number assigned by 
FEMA to each community for tracking purposes under the NFIP. 
On newer Flood Insurance Rate Maps (FIRMs) the state FIPS and 
the community number appear below the community name where 


it is shown in the body of the map. For single jurisdiction FIRMs, 
this is the 3rd through the 6th digits of the panel number. This 
number can be obtained from the community status book that can 
be viewed at www.fema.gov/msc. Areas under Federal jurisdiction 
such as National Parks, National Forests, military bases, etc. do not 
have community numbers assigned by FEMA. These areas should 
have a value of FED in the COMM_NO field. Areas under state 
jurisdiction such as state parks and wildlife reservations should 
have a value of ST in the COMM_NO field. For any other 
jurisdictions where local community does not have the authority to 
administer the NFIP and FEMA does not assign a community 
number, the COMM_NO field should contain OTHR. 

CID R S Community Identification Number. This is the six-digit community 
identification number assigned by FEMA. It is created by 
combining the state FIPS code with the COMM_NO. If the 
jurisdiction does not have a community number assigned by 
FEMA, the CID is created by combining the state FIPS code with 
the abbreviation contained in the COMM_NO field (FED, ST, or 
OTHR). 

ANI_TF R S Area Not Included. This field contains information about the 
geographical area to determine if it is included in the FIRM or not. 
Areas Not Included fall within the extent of the map, but no flood 
risk information is shown on the FIRM. This is either because the 
area is mapped on another FEMA map or because the area is not 
mapped at all by FEMA. Enter T for true or F for false. 

COM_NFO_ID A S Community Information Identification. This attribute links to the 
table L_Comm_Info that contains information about the specific 
community. This table should contain a number that matches a 
corresponding number in the COM_NFO_ID field of the 
L_Comm_Info table. This field is populated for any jurisdiction 
that has a CID number issued by FEMA. 


Table: S_Pol_Ar

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
POL_AR_ID R S text 11 string 11 character 11 11 character 11 
POL_NAME1 R S text 50 string 50 character 50 50 character 50 
POL_NAME2 R S text 50 string 50 character 50 50 character 50 
CO_FIPS R S text 3 string 3 character 3 3 character 3 
ST_FIPS R S text 2 string 2 character 2 2 character 2 
COMM_NO R S text 4 string 4 character 4 4 character 4 
CID R S text 6 string 6 character 6 6 character 6 
ANI_TF R S text 1 string 1 character 1 1 character 1 
COM_NFO_ID A S text 11 string 11 character 11 11 character 11 

L-108


Table: S_Pol_Ln 

This table is required for all draft Digital Flood Insurance Rate Map data. 

The S_Pol_Ln table contains information about the boundaries of Political Areas within the 
study area. This would include the attributes for the political areas and other areas such as 
forests, parks, military lands, and Native American lands. A spatial file with locational 
information also corresponds with this data table. 

The spatial elements representing the boundaries of the political jurisdictions depicted on the 
Flood Insurance Rate Map (FIRM) are lines. 

This is a Standard DFIRM Database table. 

The S_Pol_Ln table contains the following elements. 

POL_LN_ID R S Primary key for table lookup. Assigned by table creator. 

LN_LID R S Line Lookup Identification. A code that provides a link to a valid 
entry from the D_Ln_Typ table. These line types describe the 
jurisdictional boundary and can be used to indicate how the feature 
should be depicted on the hardcopy FIRM. 

SOURCE_CIT R S Source Citation. Abbreviation used in the metadata file when 
describing the source information for the S_Pol_Ln table. 


Table: S_Pol_Ln

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
POL_LN_ID R S text 11 string 11 character 11 11 character 11 
LN_LID R S text 11 string 11 character 11 11 character 11 
SOURCE_CIT R S text 11 string 11 character 11 11 character 11 

L-110


Table: S_Precip_Gage 

This table is required when rain gages are used in developing the hydrologic analysis. A spatial 
file with locational information also corresponds with this data table. 

The spatial elements representing the precipitation gages are points. 

This is an Enhanced DFIRM Database table. 

The S_Precip_Gage table contains the following elements. 

PRECIP_ID R E Primary key for this table. Assigned by table creator. 

GAGE_ID R E Rain Gage Identification Number. The ID for the rain gage. 
Assigned by agency maintaining gage. 

AGENCY R E Agency. Name of agency maintaining gage. 

CASE_NO R E FEMA Case Number. The case number for the rain gage links to 
the L_Case_Info table. 

GAGE_LID R E Rain Gage Type Lookup Identification. A code that provides a link 
to a valid entry from the D_Gage table. This attribute establishes 
gage type. Values include tipping, instantaneous, and fixed 
interval. 

REC_INTVL A E Recording Interval. This field is populated only if the rain gage is a 
fixed-interval gage. 

TIME_LID A E Recording Interval Time Unit Lookup Identification. A code that 
provides a link to a valid entry from the D_Time_Units table. This 
attribute establishes the unit of measure of the recording interval. 
This field is populated only if the rain gage is a fixed-interval gage. 

START_PD R E Start Period. This value is the start of the earliest period of record 
used in the gage analysis. 

END_PD R E End Date. This value is the end of the latest period of record used 
in the gage analysis. 

SOURCE_CIT R E Source Citation. Abbreviation used in the metadata file when 
describing the source information for S_Precip_Gage. 


Table: S_Precip_Gage

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
PRECIP_ID R E text 11 string 11 character 11 11 character 11 
GAGE_ID R E text 25 string 25 character 25 25 character 25 
AGENCY R E text 150 string 150 character 150 150 character 150 
CASE_NO R E text 12 string 12 character 12 12 character 12 
GAGE_LID R E text 11 string 11 character 11 11 character 11 
REC_INTVL A E text 11 string 11 character 11 11 character 11 
TIME_LID A E text 11 string 11 character 11 11 character 11 
START_PD R E date/time 8 yyyymmdd 00/00/0000 date date 8 10 date 
END_PD R E date/time 8 yyyymmdd 00/00/0000 date date 8 10 date 
SOURCE_CIT R E text 11 string 11 character 11 11 character 11 

L-112


Table: S_Profil_Basln 

This table is required for a detailed study when hydrologic and hydraulic models have been 
developed for reaches of streams. The results of the models are shown on the FIRM. The profile 
baseline and/or stream centerline may or may not be shown on the FIRM. 

The S_Profil_Basln table contains information about profile baseline and stream centerline 
features for the study area. A spatial file with locational information also corresponds with this 
data table. The spatial elements representing the profile baseline and stream centerline are lines. 

This is an Enhanced DFIRM Database table. 

The S_Profil_Basln table contains the following elements. 

BASELN_ID R E Primary key for table lookup. Assigned by table creator. 

WTR_NM_LID R E Surface Water Feature Name Lookup Identification. A code that 
provides a link to the name of the water feature associated with the 
cross section. The water feature name is taken from the table 
L_Wtr_Nm. This is a lookup table that is populated by the creator 
of the database. 

WATER_LID R E Surface Water Feature Lookup Identification. A code that provides 
a link to valid entries from the D_Water_Typ table. The type value 
describes the kind of watercourse represented. Valid entries 
include items such as profile baseline, hydrologic link, and stream 
centerline. 

UP_NODE A E Upstream Node. This is the node ID at the upstream end of the 
reach. This ID field must contain a number that matches the 
NODE_ID field in the S_Nodes table, which documents points used 
to define the topology of the hydrologic network. This field is only 
populated when WATER_LIDs value equals PROFILE 
BASELINE or PROFILE BASELINE AND STREAM 
CENTERLINE. 

DN_NODE A E Downstream Node. This is the node ID at the downstream end of 
the reach. This ID field must contain a number that matches the 
NODE_ID field for a record in the S_Nodes table, which 
documents points used to define the topology of the hydrologic 
network. This field is only populated when WATER_LIDs value 
equals PROFILE BASELINE or PROFILE BASELINE AND 
STREAM CENTERLINE. 

ROUTE_METH A E Hydrologic Routing Method. This is the hydrologic routing method 
used for the reach. This field is only populated if hydrologic 
routing is used for the reach. 


SHOWN_FIRM R E Profile Baseline Shown on FIRM. This field is true only if the 
centerline is shown on the FIRM. Enter T for true or F for 
false. 

SOURCE_CIT R E Source Citation. Abbreviation used in the metadata file when 
describing the source information for the S_Profil_Basln. 


Table: S_Profil_Basln

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
BASELN_ID R E text 11 string 11 character 11 11 character 11 
WTR_NM_LID R E text 11 string 11 character 11 11 character 11 
WATER_LID R E text 11 string 11 character 11 11 character 11 
UP_NODE A E text 11 string 11 character 11 11 character 11 
DN_NODE A E text 11 string 11 character 11 11 character 11 
ROUTE_METH A E text 254 string 254 character 254 254 character 254 
SHOWN_FIRM R E text 1 string 1 character 1 1 character 1 
SOURCE_CIT R E text 11 string 11 character 11 11 character 11 

L-115


Table: S_Quad_Index 

This table is required for all draft Digital Flood Insurance Rate Map data. 

The S_Quad_Index table contains information about the US Geological Survey (USGS) 7.5-
Minute Series Topographic Quadrangle maps that cover the study area. While USGS 7.5-minute 
quadrangles do not meet the Federal Emergency Management Agency (FEMA) digital base map 
standards, they are often useful as a supplementary reference source. The quadrangle 
information is provided as a convenience to users who may want to cross-reference this map 
series. A spatial file with locational information also corresponds with this data table. 

The spatial entities representing the USGS quadrangles are polygons. Each polygon corresponds 
to the neatline of a USGS map. 

This is a Standard DFIRM Database table. 

The S_Quad_Index table contains the following elements. 

QUAD_ID R S Primary key for table lookup. Assigned by table creator. 

QUAD_NO R S Quad Number. This is the eight-digit USGS alphanumeric 
quadrangle identifier. The list of values for each state is published 
by USGS in the State Indexes to Topographic and Other Map 
Coverage. This item is composed of three components: the latitude, 
rounded down to the nearest whole degree, of the 7.5-minute 
quadrangle map sheet; the longitude, rounded down to the nearest 
whole degree, of the 7.5-minute quadrangle map sheet; and the 
alphanumeric map sheet identifier used by USGS (i.e., A1 through 
H8). 

QUAD_NM R S Quad Name. This is the name of the quad that is assigned by 
USGS. 

SOURCE_CIT R S Source Citation. Abbreviation used in the metadata file when 
describing the source information for S_Quad_Index table. 


Table: S_Quad_Index

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
QUAD_ID R S text 11 string 11 character 11 11 character 11 
QUAD_NO R S text 8 string 8 character 8 8 character 8 
QUAD_NM R S text 50 string 50 character 50 50 character 50 
SOURCE_CIT R S text 11 string 11 character 11 11 character 11 

L-117


Table: S_Riv_Mrk 

This table is required if the Flood Insurance Rate Map (FIRM) shows river distance marks. 

The S_Riv_Mrk table contains information about the River Marks shown on the hardcopy FIRM 
if applicable. A spatial file with locational information also corresponds with this data table. 

The spatial entities representing the river marks are points. The points are generally located 
along side of the river at regular intervals. 

This is a Standard DFIRM Database table. 

The S_Riv_Mrk table contains the following elements.
RIV_MRK_ID R S Primary key for table lookup. Assigned by table creator.

START_ID R S Start Identification. A code that provides a link to a point in the 
L_Stn_Start table at which the river mark distances start. 

RIV_MRK_NO R S River Mark Number. This attribute usually represents the distance 
from a known point (identified by START_ID), such as the 
confluence with another river, to the current river mark. This is the 
value shown next to the river mark on the FIRM. 

SOURCE_CIT R S Source Citation. Abbreviation used in the metadata file when 
describing the source information for the S_Riv_Mrk table. 


Table: S_Riv_Mrk

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
RIV_MRK_ID R S text 11 string 11 character 11 11 character 11 
START_ID R S text 11 string 11 character 11 11 character 11 
RIV_MRK_NO R S text 6 string 6 character 6 6 character 6 
SOURCE_CIT R S text 11 string 11 character 11 11 character 11 

L-119


Table: S_Shore_Ln 

This table is required for coastal modeling studies. 

The S_Shore_Ln table contains information about the shoreline used in the coastal flood hazard 
model. Typically, the S_Shore_Ln represents to 0.0-foot elevation contour. The S_Shore_Ln 
shoreline may not be shown on the FIRM but must be archived for informational purposes. The 
mapped shoreline is stored in the S_Wtr_Ln table of the standard DFIRM database. A spatial 
file with locational information also corresponds with this data table. 

The spatial elements representing the shorelines are lines. 

This is an Enhanced DFIRM Database table. 

The S_Shore_Ln table contains the following elements. 

SHR_LN_ID R E Primary key for table lookup. Assigned by table creator. 

SHRTYP_LID R E Shoreline Type Lookup Identification. A code that provides a link 
to a valid shoreline type from the D_Shr_Typ table. This value 
describes the criteria used in determining the shoreline in coastal 
flood hazard models. 

V_DATM_LID R E Vertical Datum Lookup Identification. A code that provides a link 
to a valid vertical datum from the D_V_Datum table. The vertical 
datum indicates the reference surface from which the 0.0-foot 
contour is measured. Normally this would be North American 
Vertical Datum of 1988 for new studies. 

SOURCE_CIT R E Source Citation. Abbreviation used in the metadata file when 
describing the source information for the S_Shore_Ln table. 


Table: S_Shore_Ln

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
SHR_LN_ID R E text 11 string 11 character 11 11 character 11 
SHRTYP_LID R E text 11 string 11 character 11 11 character 11 
V_DATM_LID R E text 11 string 11 character 11 11 character 11 
SOURCE_CIT R E text 11 string 11 character 11 11 character 11 

L-121


Table: S_Stn_Start 

This table is required when the geographic location of station start points exist. 

The S_Stn_Start contains information about station points. These points indicate the reference 
point that was used as the origin for distance measurements along streams and rivers. This table 
links to descriptive information in the L_Stn_Start table. A spatial file with locational 
information also corresponds with this data table. 

The spatial entity representing station starting locations are points. The point should be located 
on the stream centerline at the place where the measurements begin. This point may be outside 
the jurisdiction mapped in some cases. The location of the stationing start for a group of cross 
sections is normally referenced as a note on the floodway data table and on the flood profiles. 
Generally, all the cross sections for a particular reach are reference to the same starting point. 

This is an Enhanced DFIRM Database table. 

The S_Stn_Start table contains the following elements. 

STRT_PT_ID R E Primary key for this table. Assigned by table creator. 

START_ID R E Start Identification. This is a link to the station start lookup table. 
The station start describes the origin for the measurements in the 
STREAM_STN field. This field must contain a number that links 
to a unique value in the START_ID field in the L_Stn_Start table. 

SOURCE_CIT R E Source Citation. Abbreviation used in the metadata file when 
describing the source information for S_Stn_Start. 


Table: S_Stn_Start

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
STRT_PT_ID R E text 11 string 11 character 11 11 character 11 
START_ID R E text 11 string 11 character 11 11 character 11 
SOURCE_CIT R E text 11 string 11 character 11 11 character 11 

L-123


Table: S_Subbasins 

This table is required for all studies with new or revised hydrologic data. 

The S_Subbasins table contains data specific to each subbasin in the hydrologic analysis, including the 
subbasins relationship to the hydrologic network. The subbasin may be the subbasin specific to a 
detailed hydrologic model. It may also correspond to the drainage area used in a regression analysis, or to 
the drainage area for a stream gage. A spatial file with locational information also corresponds with this 
data table. 

The spatial elements representing the subbasins are polygons. In some cases the extent of these 
polygons may overlap, for example, cumulative subbasin areas for a regression analysis. 

This is an Enhanced DFIRM Database table. 

The S_Subbasins table contains the following elements. 

SUBBAS_ID R E Primary key for this table. Assigned by table creator. 

SUBBAS_NM R E Name of subbasin. 

NODE_ID R E Node Identification. A code that provides a link to a valid entry 
from the S_Nodes table. ID for the load/outflow point (pourpoint) 
for the subbasin. 

SOURCE_CIT R E Source Citation. Abbreviation used in the metadata file when 
describing the source information for S_Subbasins. 


Table: S_Subbasins

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
SUBBAS_ID R E text 11 string 11 character 11 11 character 11 
SUBBAS_NM R E text 254 string 254 character 254 254 character 254 
NODE_ID R E text 11 string 11 character 11 11 character 11 
SOURCE_CIT R E text 11 string 11 character 11 11 character 11 

L-125


Table: S_Trnsport_Ln 

This table or an equivalent that is fully documented is required for all Digital Flood Insurance 
Rate Map databases that use a vector rather than raster base map data. 

The S_Trnsport_Ln table contains information about the linear base map transportation features 
such as roads, railroads, and airports. A spatial file with locational information also corresponds 
with this data table. 

The spatial entities representing linear transportation features are normally lines. However, if the 
available transportation data depict roads as polygons, this is acceptable also. In general, the 
transportation table structure is fairly flexible depending on the format of the data available for 
the map. The Federal Emergency Management Agencys (FEMAs) objective is to have 
spatially accurate base map data to which the flood hazard information is referenced. Users must 
be able to identify the names of roads, railroads and other major features in or near the Special 
Flood Hazard Areas (SFHAs). If these objectives are met, then almost any file structure is 
acceptable. Road centerlines or edge of pavement files are both acceptable, provided that they 
meet the FEMA base map standard. With some data structures, it may not be practical to assign 
feature names or other attributes to each spatial entity. While these attributes are desirable, 
FEMA recognizes that they may not always be easily available. This is acceptable because the 
S_Label_Pt and S_Label_Ld tables will identify the names of all of the important features in or 
near the SFHA. 

This is a Standard DFIRM Database table. 

The S_Trnsport_Ln table contains the following elements. 

TRANS_ID R S Primary key for table lookup. Assigned by table creator. 

TRANS_LID R S Transportation Lookup Identification. A code that provides a link 
to valid entries from the D_Trans_Typ table. These line types 
indicate how the feature should be depicted on the hardcopy Flood 
Insurance Rate Map. 

RD_S_LID R S Road Status Lookup Identification. A code that provides a link to 
valid entries in the D_Rd_Stat table. 

PREFIX A S Prefix of the Feature Name. Not all features will have an entry in 
this attribute. Valid entries might include N for a transportation 
feature named N Main Street. 

FEAT_NM1 R S Feature Name 1. This is the primary name of the feature. For areas 
that have more than one name, this would be the primary name with 
subsequent names shown in fields below. Route numbers and 
Intercoastal Waterway would also be included in this item. 


NM_LID R S Name Type Lookup Identification. A code that provides a link to 
valid entries in the D_Nm_Typ table. 

SUFFIX A S Suffix of the Feature Name. Not all features will have an entry in 
this attribute. Valid entries might include NW for a transportation 
feature named Main Street NW. 

FEAT_NM2 A S Feature Name 2. This is the secondary name of the feature. 

FEAT_NM3 A S Feature Name 3. This is the tertiary name of the feature. 

SOURCE_CIT R S Source Citation. Abbreviation used in the metadata file when 
describing the source information for the S_Trnsport_Ln table. 


Table: S_Trnsport_Ln

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
TRANS_ID R S text 11 string 11 character 11 11 character 11 
TRANS_LID R S text 11 string 11 character 11 11 character 11 
RD_S_LID R S text 11 string 11 character 11 11 character 11 
PREFIX A S text 50 string 50 character 50 50 character 50 
FEAT_NM1 R S text 100 string 100 character 100 100 character 100 
NM_LID R S text 11 string 11 character 11 11 character 11 
SUFFIX A S text 50 string 50 character 50 50 character 50 
FEAT_NM2 A S text 100 string 100 character 100 100 character 100 
FEAT_NM3 A S text 100 string 100 character 100 100 character 100 
SOURCE_CIT R S text 11 string 11 character 11 11 character 11 

L-128


Table: S_Water_Gage 

This table is required when non-rain gages are used in developing the hydrologic analysis. A 
spatial file with locational information also corresponds with this data table. 

The spatial elements representing the water gages are points. 

This is an Enhanced DFIRM Database table.
The S_Water_Gage table contains the following elements.
GAG_WTR_ID R E Primary key for this table. Assigned by table creator.

GAGE_ID R E Gage Identification. Assigned by the agency maintaining the gage. 
AGENCY R E Agency. Name of the agency maintaining the gage. 

GAGE_LID R E Gage Type Lookup Identification. A code that provides a link to a 
valid entry from the D_Gage table. This attribute establishes the 
gage type. Values include flow, stage, wind direction, wind speed, 
wave, and tide. 

REC_INTVL R E Recording Interval. Recording interval for the gage. 

TIME_LID R E Recording Interval Time Unit Lookup Identification. A code that 
provides a link to a valid entry from the D_Time_Units table. This 
attribute establishes the unit of measure of the recording interval. 

CASE_NO R E FEMA Case Number. The case number for the water gage links to 
the L_Case_Info table. 

START_PD R E Start Period. This value is the start of the earliest period of record 
used in the gage analysis. 

END_PD R E End Period. This value is the end of the latest period of record used 
in the gage analysis. 

SOURCE_CIT R E Source Citation. Abbreviation used in the metadata file when 
describing the source information for S_Water_Gage. 


Table: S_Water_Gage

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
GAG_WTR_ID R E text 11 string 11 character 11 11 character 11 
GAGE_ID R E text 25 string 25 character 25 25 character 25 
AGENCY R E text 150 string 150 character 150 150 character 150 
GAGE_LID R E text 11 string 11 character 11 11 character 11 
REC_INTVL R E text 11 string 11 character 11 11 character 11 
TIME_LID R E text 11 string 11 character 11 11 character 11 
CASE_NO R E text 12 string 12 character 12 12 character 12 
START_PD R E date/time 8 yyyymmdd 00/00/0000 date date 8 10 date 
END_PD R E date/time 8 yyyymmdd 00/00/0000 date 11 date 8 10 date 11 
SOURCE_CIT R E text 11 string 11 character 11 11 character 11 

L-130


Table: S_Wtr_Ar 

This table is required for any Digital Flood Insurance Rate Map (DFIRM) database where vector 
surface water features are shown on the Flood Insurance Rate Map and some of these features 
are represented as polygons in the spatial data. Vector streams should always be shown with a 
vector base map. They may also be shown on raster base maps. 

The S_Wtr_Ar table contains information about surface water area features. A spatial file with 
locational information also corresponds with this data table. 

The spatial elements representing surface water area features are polygons. Normally lakes, 
ponds and streams wide enough to show both channel banks will be represented as polygons. 
However, the main purpose of the S_Wtr_Ar table and the S_Wtr_Ln table are to provide a 
cartographic depiction of the surface water features for visual interpretation of the mapping data. 
As a result, the method for structuring surface water features as lines or polygons is very flexible. 
Surface water features may appear in either the S_Wtr_Ar table or the S_Wtr_Ln table or both. 
However, features that appear in both must match exactly. The hydrologic structure of the 
stream network will be represented by tables in the Enhanced DFIRM Database. 

In general, the surface water table structure is fairly flexible depending on the format of the data 
available for the map. The Federal Emergency Management Agencys (FEMAs) objective is to 
have spatially accurate surface water feature data to which the flood hazard information is 
referenced. Users must be able to identify the names of flooding sources and other important 
surface water features. If these objectives are met, then almost any file structure is acceptable. 
Streams, rivers and lakes may be represented as either polygons or lines. With some data 
structures, it may not be practical to assign feature names or other attributes to each spatial 
entity. While these attributes are desirable, FEMA recognizes that they may not always be easily 
available. This is acceptable because the S_Label_Pt and S_Label_Ld tables will identify the 
names of flooding sources and other important surface water features. 

This is a Standard DFIRM Database table. 

The S_Wtr_Ar table contains the following elements. 

WTR_AR_ID R S Primary key for table lookup. Assigned by table creator. 

WATER_LID R S Surface Water Feature Lookup Identification. A code that provides 
a link to valid entries from the D_Water_Typ table. This type value 
describes the classification of the surface water feature. Valid 
entries include items such as lake, retention pond, and reservoir. 

WTR_NM_LID R S Surface Water Name Lookup Identification. A code that provides a 
link to the name of the surface water feature. The surface water 
feature name is taken from the table L_Wtr_Nm. This is a lookup 
table that is populated by the creator of the database. 


SOURCE_CIT R S Source Citation. Abbreviation used in the metadata file when 
describing the source information for the S_Wtr_Ar table. 


Table: S_Wtr_Ar

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
WTR_AR_ID R S text 11 string 11 character 11 11 character 11 
WATER_LID R S text 11 string 11 character 11 11 character 11 
WTR_NM_LID R S text 11 string 11 character 11 11 character 11 
SOURCE_CIT R S text 11 string 11 character 11 11 character 11 

L-133


Table: S_Wtr_Ln 

This table is required for any Digital Flood Insurance Rate Map (DFIRM) database where vector 
surface water features are shown on the Flood Insurance Rate Map and some of these features 
are represented as lines in the spatial data. Vector streams should always be shown with a vector 
base map. They may also be shown on raster base maps. 

The S_Wtr_Ln table contains information about surface water linear features. A spatial file with 
locational information also corresponds with this data table. 

The spatial elements representing surface water line features are lines. Normally stream 
centerlines will be represented as line features. However, the main purpose of the S_Wtr_Ar 
table and the S_Wtr_Ln table are to provide a cartographic depiction of the surface water 
features for visual interpretation of the mapping data. As a result, the method for structuring 
surface water features as lines or polygons is very flexible. Lake shorelines and stream channel 
banks used to show lakes and wide rivers are usually represented as polygons. However, they 
may be represented as lines based on the structure of the data received and the Mapping Partners 
discretion. Surface water features may appear in either the S_Wtr_Ar table or the S_Wtr_Ln 
table or both. However, features that appear in both must match exactly. The hydrologic 
structure of the stream network will be represented by tables in the Enhanced DFIRM Database. 

In general, the surface water table structure is fairly flexible depending on the format of the data 
available for the map. The Federal Emergency Management Agencys (FEMAs) objective is to 
have spatially accurate surface water feature data to which the flood hazard information is 
referenced. Users must be able to identify the names flooding sources and other important 
surface water features. If these objectives are met, then most any file structure is acceptable. 
Streams, rivers and lakes may be represented as polygons or lines. With some data structures, it 
may not be practical to assign feature names or other attributes to each spatial entity. While 
these attributes are desirable, FEMA recognizes that they may not always be easily available. 
This is acceptable because the S_Label_Pt and S_Label_Ld tables will identify the names of 
flooding sources and other important surface water features. 

This is a Standard DFIRM Database table. 

The S_Wtr_Ln table contains the following elements. 

WTR_LN_ID R S Primary key for table lookup. Assigned by table creator. 

WATER_LID R S Surface Water Feature Lookup Identification. A code that provides 
a link to valid entries from the D_Water_Typ table. The type value 
describes the kind of watercourse represented. Valid entries 
include items such as stream/river, channel, and shoreline/coastline. 

CHAN_LID R S Channel Lookup Identification. A code that provides a link to valid 
entries from the D_Chan_Rep table. This channel type value 
indicates whether a linear water feature is represented as a stream 


centerline or represented as channel bank locations. Valid entries 
include single or double. 

WTR_NM_LID R S Water Name Lookup Identification. A code that provides a link to 
the name of the water feature. The water feature name is taken 
from the table L_Wtr_Nm. This is a lookup table that is populated 
by the creator of the database. 

SOURCE_CIT R S Source Citation. Abbreviation used in the metadata file when 
describing the source information for the S_Wtr_Ln table. 


Table: S_Wtr_Ln

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
WTR_LN_ID R S text 11 string 11 character 11 11 character 11 
WATER_LID R S text 11 string 11 character 11 11 character 11 
CHAN_LID R S text 11 string 11 character 11 11 character 11 
WTR_NM_LID R S text 11 string 11 character 11 11 character 11 
SOURCE_CIT R S text 11 string 11 character 11 11 character 11 

L-136


Table: S_XS 

This table is required for any Digital Flood Insurance Rate Map database where cross sections 
are shown on the Flood Insurance Rate Map (FIRM). Normally any FIRM that has associated 
flood profiles has cross sections. 

The S_XS table contains information about cross section lines. A spatial file with locational 
information also corresponds with this data table. These lines represent the locations of channel 
surveys performed for input into the hydraulic model used to calculate flood elevations. These 
locations are also shown on the Flood Profiles in the Flood Insurance Study (FIS) report and can 
be used to cross reference the Flood Profiles to the planimetric depiction of the flood hazards. 
All cross sections for which a spatial location is available should be included in this table. 

The spatial elements representing cross sections are lines generally extending from outside the 
floodplain, across the entire floodplain and out the other side. Each cross section should be 
represented by a single line feature without the hexagons shown on each end on the hardcopy 
map. The location and shape of the lines should depict as accurately as possible the position of 
the cross section used. 

This is a modified Standard DFIRM Database table that includes Standard DFIRM Database 
items and Enhanced Database items. All items after SOURCE_CIT are Enhanced. The 
Enhanced DFIRM Database must contain all modeled cross sections, whether they are printed on 
the FIRM or not. 

The S_XS table contains the following elements. 

XS_LN_ID R S Primary key for table lookup. Assigned by table creator. 

XS_LTR A S Cross-Section Letter. The letter or number that is assigned to the 
cross section on the hardcopy FIRM and in the FIS report. This 
attribute is blank if the cross section is not shown on the FIRM. For 
a digital conversion, only cross sections that are shown on the 
FIRM will be available. 

START_ID R S Start Identification. This is a link to the station start lookup table. 
The station start describes the origin for the measurements in the 
STREAM_STN field. This field should contain a number that links 
to a unique value in the START_ID field in the L_Stn_Start table. 

STREAM_STN R S Stream Station. This is the measurement along the stream to the 
cross-section location. Normally this information is available in the 
Floodway Data table in the FIS report. When no Floodway Data 
table is published, this value can be read from the horizontal scale 
of the flood profile. The units are clarified in the description in the 
START_DESC field in the L_Stn_Start table. 


XS_LN_TYP R S Cross-Section Line Type. This attribute should contain 
LETTERED for cross sections that are shown on the hardcopy 
FIRM. If the cross section will not be shown on the hardcopy 
FIRM, this attribute should contain NOT LETTERED to indicate 
that the cross section is part of the backup data for the study, but is 
not shown on the FIRM. 

WTR_NM_LID R S Surface Water Feature Name Lookup Identification. A code that 
provides a link to the name of the water feature associated with the 
cross section. The water feature name is taken from the table 
L_Wtr_Nm. This is a lookup table that is populated by the creator 
of the database. 

WSEL_REG R S Regulatory Water-Surface Elevation for the 1-Percent-Annual-
Chance Flood Event. This is the precise water surface elevation of 
the base flood calculated at this cross section. This elevation 
exactly matches the elevation of the base flood in the Flood Profiles 
and the Floodway Data table. This number is determined during the 
engineering analysis for the study. This value should match the 
regulatory column in the Floodway Data table in the FIS report or 
the elevation from the corresponding flood profile if no Floodway 
Data table is published. 

LEN_LID R S Length Unit Lookup Identification. A code that provides a link to 
valid unit of length from the D_Length_Units table. The unit 
specifies the system of measurement for the water surface elevation. 
For the Enhanced Database, this attribute also specifies the length 
unit for stream bed elevation and top width. Normally this would 
be feet. 

V_DATM_LID R S Vertical Datum Lookup Identification. A code that provides a link 
to a valid vertical datum from the D_V_Datum table. The vertical 
datum indicates the reference surface from which the flood 
elevations are measured. Normally this would be North American 
Vertical Datum of 1988 for new studies. 

SOURCE_CIT R S Source Citation. Abbreviation used in the metadata file when 
describing the source information for the S_XS table. Table: 

BED_ELEV R E Streambed Elevation. The elevation of the streambed at this cross 
section as shown on the Flood Profile in the FIS. 

TOP_WIDTH R E Top Width. Width of the floodway at this cross section as shown in 
the Floodway Data table in the FIS. 

XS_AREA R E Cross Section Area. Area of the cross section underwater for the 
width of the floodway as shown in the Floodway Data table in the 
FIS. 


AREA_LID R E Area Unit Lookup Identification. A code that provides a link to a 
valid areal unit from the D_Area_Units table. This unit specifies 
the areal unit for the area of the cross section underwater for the 
width of the floodway. 

VELOCITY R E Mean Velocity. The mean velocity of the floodway at this cross 
section as shown in the Floodway Data table in the FIS. 

VEL_LID R E Velocity Lookup Identification. A code that provides a link to a 
valid velocity unit from the D_Vel_Units table. This unit specifies 
the unit of measurement for the velocity of the floodway. 


Table: S_XS

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
XS_LN_ID R S text 11 string 11 character 11 11 character 11 
XS_LTR A S text 12 string 12 character 12 12 character 12 
START_ID R S text 11 string 11 character 11 11 character 11 
STREAM_STN R S text 12 string 12 character 12 12 character 12 
XS_LN_TYP R S text 20 string 20 character 20 20 character 20 
WTR_NM_LID R S text 11 string 11 character 11 11 character 11 
WSEL_REG R S 
number 
(double) 8 2 number 13 2 numeric 8 13 2 decimal 15 2 
LEN_LID R S text 11 string 11 character 11 11 character 11 
V_DATM_LID R S text 11 string 11 character 11 11 character 11 
SOURCE_CIT R S text 11 string 11 character 11 11 character 11 
BED_ELEV R E 
number 
(double) 8 2 number 13 2 numeric 8 13 2 decimal 15 2 
TOP_WIDTH R E number 8 2 number 13 2 numeric 8 13 2 decimal 15 2 

L-140


(double) 
XS_AREA R E 
number 
(double) 8 2 number 13 2 numeric 8 13 2 decimal 15 2 
AREA_LID R E text 11 string 11 character 11 11 character 11 
VELOCITY R E 
number 
(double) 8 2 number 13 2 numeric 8 13 2 decimal 15 2 
VEL_LID R E text 11 string 11 character 11 11 character 11 

L-141


Table: Study_Info 

This table is required for all draft Digital Flood Insurance Rate Map data. 

The Study_Info table contains details about the study such as the study name, datum, projection, 
etc. There is normally only one record in this table for each Flood Insurance Rate Map (FIRM). 

This is a modified Standard DFIRM Database table that includes Standard DFIRM Database 
items and Enhanced Database items. The item STUDY_ZIP is Enhanced. 

The Study_Info table contains the following elements. 

STD_NFO_ID R S Primary key for table lookup. Assigned by table creator. 

STUDY_PRE A S Study Prefix. This is the prefix of the study name such as City of 
or Town of. This field is applicable for single jurisdiction maps 
where the type of jurisdiction precedes the name of the jurisdiction 
in the map title. For county-wide maps or maps of the 
unincorporated portions of a county, this field is NULL. 

STUDY_NM R S Study Name. This attribute contains the main portion of the study 
name, which is shown in the title block of the hardcopy FIRM. For 
county-wide FIRMs, or FIRMs for the unincorporated portions of 
counties, the name should include the county or county equivalent 
descriptor (e.g. Washington County or Iberia Parish). 

STATE_NM R S State Name. This attribute contains the state name for the study and 
is shown in the title block of the hardcopy FIRM. 

CNTY_NM R S County Name. This is the county (or county equivalent) name that 
the study falls within. The name should include the county or 
county equivalent descriptor (e.g. Washington County or Iberia 
Parish). The county name is also shown in the title block section of 
the hardcopy FIRM. 

JURIS_TYP A S Political Jurisdiction Type. This attribute contains entries such as 
Unincorporated Areas or All Jurisdictions or and Incorporated 
Areas. This field is applicable when the type of map is 
Unincorporated Areas or All Jurisdictions or and Incorporated 
Areas. For a single jurisdiction map, this field is NULL. If there 
are data in this attribute, it is also shown in the title block section of 
the hardcopy FIRM. 

LG_PAN_NO R S Largest Panel Number. This is the highest panel number shown on 
the FIRM Index for the area mapped. This number is shown in the 
title block section of the hardcopy FIRM. 


OPP_TF R S Only Panel Printed. This field is True only if the study has only 
one printed panel. Enter T for true or F for false. 

H_DATUM R S Horizontal Datum. Valid entries for this attribute include North 
American Datum of 1927 or North American Datum of 1983 
(NAD83). This is the horizontal datum used for the printed FIRM. 
The horizontal datum describes the reference system on which the 
horizontal coordinate information shown on the FIRM is based. 
NAD83 is the preferred horizontal datum. 

V_DATM_LID R S Vertical datum Lookup Identification. A code that provides a link 
to valid vertical datum from the D_V_Datum table. This is the 
vertical datum of the printed FIRM. The vertical datum describes 
the reference surface from which elevation on the map is measured. 
Normally, this would be North American Vertical Datum of 1988 
for new studies. 

PROJECTION R S Map Projection used for hardcopy FIRM publication. The 
preferred projection is Universal Transverse Mercator (UTM). If a 
State Plane coordinate system and associated projection is used, this 
field should include the name of the projection, the state and the 
zone (e.g., Lambert Conformal Conic, Virginia North Zone). 

PROJ_ZONE A S Projection Zone. When using many map projections and coordinate 
systems, there is a zone associated with the area. This field is 
populated based on the projection selected for the Final hardcopy 
map production. Applies if the projection used has a zone 
parameter such as UTM or state plane. The zone should be stated 
as the appropriate Federal Information Processing Standard zone or 
FIPSZONE. 

CW_TF R S Countywide, true/false. This attribute is true if the hardcopy FIRM 
includes all incorporated areas and any unincorporated areas of the 
county. Enter T for true or F for false. 

CBRS_PHONE A S Coastal Barrier Resources System (CBRS) Phone number. This is 
the phone number for the contact person/office for the CBRS 
legislative area. Applies if the FIRM contains CBRS areas. Enter 
the phone number as a ten-digit numeric string with hyphens in the 
following format, 000-000-0000. 

CBRS_REG A S CBRS Coordinators region. This attribute contains the Fish and 
Wildlife Service (FWS) region within which the FIRM is located. 
Applies if the FIRM contains CBRS areas. 

RTROFT_TF R S Retrofit, True/False. The Retrofit attribute should be True if older 
study data is used with updated stream location data. If flood 
features were adjusted to fit new stream locations due to better base 


map information this attribute would be true. Enter T for true or 
F for false. 

META_NM R S Metadata File Name. This attribute stores the name of the metadata 
file. The file should be named 
<ST_FIPS><PCOMM>_<EFF_DATE>_metadata.txt; where 
ST_FIPS is the two digit state FIPS code; PCOMM is the four digit 
community or county identifcation number; and EFF_DATE is the 
effective date of the study. If the study is not yet effective, the 
effective date, <EFF_DATE>, should be replaced with the word 
PRELIM. 

STUDY_ZIP A E Name of the Study Zipfile. This attribute stores the path/filename 
of the zipped file that contains the FIS report or auxiliary data that 
is relevant to the entire study. 


Table: Study_Info

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
STD_NFO_ID R S text 11 string 11 character 11 11 character 11 
STUDY_PRE A S text 20 string 20 character 20 20 character 20 
STUDY_NM R S text 50 string 50 character 50 50 character 50 
STATE_NM R S text 50 string 50 character 50 50 character 50 
CNTY_NM R S text 50 string 50 character 50 50 character 50 
JURIS_TYP A S text 50 string 50 character 50 50 character 50 
LG_PAN_NO R S text 4 string 4 character 4 4 character 4 
OPP_TF R S text 1 string 1 character 1 1 character 1 
H_DATUM R S text 10 string 10 character 10 10 character 10 
V_DATM_LID R S text 11 string 11 character 11 11 character 11 
PROJECTION R S text 50 string 50 character 50 50 character 50 
PROJ_ZONE A S text 4 string 4 character 4 4 character 4 
CW_TF R S text 1 string 1 character 1 1 character 1 
CBRS_PHONE A S text 15 000-000-0000 000\-000\-0000 string 15 character 15 15 character 15 

L-145


CBRS_REG A S text 1 string 1 character 1 1 character 1 
RTROFT_TF R S text 1 string 1 character 1 1 character 1 
META_NM R S text 50 string 50 character 50 50 character 50 
STUDY_ZIP A E text 254 string 254 character 254 254 character 254 

L-146


Table: L_Aux_Data 

This table is required when the data developer wishes to document additional data sources used 
in developing the study. The table may be used to document other data sets such as topography, 
soils, land use, coastal roughness, etc. 

This is an Enhanced DFIRM Database table.
The L_Aux_Data table contains the following elements.
DATA_ID R E Primary key for this table. Assigned by table creator.

CASE_NO R E FEMA Case Number. The case number for the auxiliary data links 
to the L_Case_Info table. 

DATA_DATE R E Date the data was prepared (e.g., date of file originally supplied by 
Mapping Partner). 

DATA_TYPE R E Description of data set. 

ORG_NAME A E Organization which generated/supplied the data. 
CONTACT A E Name of contact person. 

TITLE A E Title of contact person. 

PHONE A E Phone number of contact person/organization. Enter the phone 
number as a ten-digit numeric string with hyphens in the following 
format, 000-000-0000. 

ADDRESS1 A E Line 1 of mailing address of contact person/organization.

ADDRESS2 A E Line 2 of mailing address of contact person/organization.
ADDRESS3 A E Line 3 of mailing address of contact person/organization.
CITY A E City of contact person/organization.

STATE A E State/Territory/Commonwealth of contact person/organization.
ZIP A E Postal ZIP code of contact person/organization.

FILE_NM R E Name of accompanying data file.
META_NM R E Name of metadata file that describes the accompanying dataset.


Table: L_Aux_Data

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
DATA_ID R E text 11 string 11 character 11 11 character 11 
CASE_NO R E text 12 string 12 character 12 12 character 12 
DATA_DATE R E date/time 8 yyyymmdd 00/00/0000 date date 8 10 date 
DATA_TYPE R E text 254 string 254 character 254 254 character 254 
ORG_NAME A E text 100 string 100 character 100 100 character 100 
CONTACT A E text 50 string 50 character 50 50 character 50 
TITLE A E text 25 string 25 character 25 25 character 25 
PHONE A E text 15 000-000-0000 000\-000\-0000 string 15 character 15 15 character 15 
ADDRESS1 A E text 50 string 50 character 50 50 character 50 
ADDRESS2 A E text 50 string 50 character 50 50 character 50 
ADDRESS3 A E text 50 string 50 character 50 50 character 50 
CITY A E text 50 string 50 character 50 50 character 50 
STATE A E text 50 string 50 character 50 50 character 50 
ZIP A E text 10 string 10 character 10 10 character 10 

L-148


FILE_NM R E text 254 string 25 character 25 25 character 25 
META_NM R E text 50 string 50 character 50 50 character 50 

L-149


Table: L_Case_Info 

This table is required for all studies with new or revised hydrologic data. 

The L_Case_Info table is a lookup table that contains data specific to the study, including FEMA 
Case information and general hydrologic and/or hydraulic backup information. The fields are 
populated by the Mapping Partner who creates the database. If a Case Number is not available at 
the time the table is populated, the Mapping Partner shall use a temporary unique identification 
number. 

This is an Enhanced DFIRM Database table. 

The L_Case_Info table contains the following elements. 

CASE_NO R E Primary key for this table. FEMA Case Number for study. Used to 
link to archived electronic and hardcopy data, and to link to various 
hydrologic and hydraulic data tables. 

CASE_DESC R E General description of the study, for example, the study location 
and method(s) used. 

CASE_ZIP R E Name of the Case Zipfile. This attribute stores the file name/path of 
the zipped file that contains engineering support data associated 
with the Case. 

STD_NFO_ID R E Study Information Identification. A code that provides a link to a 
valid entry from the Study_Info table. 

EFF_DATE R E Effective date of the Case. 


Table: L_Case_Info

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
CASE_NO R E text 12 string 12 character 12 12 character 12 
CASE_DESC R E text 254 string 254 character 254 254 character 254 
CASE_ZIP R E text 254 string 254 character 254 254 character 254 
STD_NFO_ID R E text 11 string 11 character 11 11 character 11 
EFF_DATE R S date/time 8 yyyymmdd 00/00/0000 date date 8 10 date 

L-151


Table: L_Comm_Info 

This table is required for all draft Digital Flood Insurance Rate Map data. 

The L_Comm_Info table is a lookup table that contains community map repository details and 
map history information that is shown on the Flood Insurance Rate Map (FIRM) legend or index. 
This table will include any community that has a CID; even if it is considered non-floodprone or 
non-participationg. Communities that do not have a CID issued by FEMA, or are not included 
within the area of the data submittal, will not appear in this table. The not populated values, 
that are described in sections L.2.5.10 and L.3.5.11, may be used to fill in some of the required 
fields when necessary. There is normally one record in this table for each community mapped 
on the FIRM. 

This is a Standard DFIRM Database table. 

The L_Comm_Info table contains the following elements. 

COM_NFO_ID R S Primary key for table lookup that links to the S_Pol_Ar table. 
Values in this field should match the values COM_NFO_ID field of 
the S_Pol_Ar table. 

REPOS_ADR1 R S First line of the mailing or street address for the map repository. 
The map repository is the office the community has designated as 
responsible for maintaining copies of all the flood hazard 
information the Federal Emergency Management Agency (FEMA) 
publishes for the community. The public may view copies of the 
current effective information at the map repository. This 
information is also displayed in the FIRM legend or index. For 
example, this line might read Division of Community and 
Economic Development. 

REPOS_ADR2 A S Second line of the mailing or street address for the map repository. 
This information is also displayed in the FIRM legend or index. 
For example, this line might read 226 W. Fourth Street. This field 
is applicable if the map repository address requires more than one 
line. 

REPOS_ADR3 A S Third line of the mailing or street address for the map repository. 
This information is also displayed in the FIRM legend or index. 
For example, this line might read Suite 200. This field is 
applicable if address requires additional space. 

REPOS_CITY R S City portion of the mailing or street address for the map repository. 
This information is also displayed in the FIRM legend or index. 
For example, this line might read Springfield. 


REPOS_ST R S State portion of the mailing or street address for the map repository. 
This information is also displayed in the FIRM legend or index. 
The full name of the state should be provided. For example, this 
line might read ILLINOIS. 

REPOS_ZIP R S ZIP Code portion of the mailing or street address for the map 
repository. This information is also displayed in the FIRM legend 
or index. For example, this line might read 62269. 

IN_ID_DAT R S Initial identification date for the community as shown on the FIRM 
legend, index, or Flood Insurance Study (FIS) report. This 
information can also be obtained from FEMA. See Appendix K of 
these Guidelines for more detailed information about map dates. 

IN_NFIP_DT R S Initial date of the first National Flood Insurance Program map 
published by FEMA for this community. This can be obtained 
from the FIRM legend, index, or FIS report. This information can 
also be obtained from FEMA. See Appendix K of these Guidelines 
for more detailed information about map dates. 

IN_FRM_DAT R S Initial date FIRM was created. This can be obtained from the 
FIRM legend, index, or FIS report. This information can also be 
obtained from FEMA. See Appendix K of these Guidelines for 
more detailed information about map dates. 

RECENT_DAT A S Most recent panel date. This can be obtained from the FIRM Index 
or the FEMA Community Status book at www.fema.gov/msc. 
This field is only populated for final DFIRM Databases. See 
Appendix K of these Guidelines for more detailed information 
about map dates. 


Table: L_Comm_Info

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
COM_NFO_ID R S text 11 string 11 character 11 11 character 11 
REPOS_ADR1 R S text 50 string 50 character 50 50 character 50 
REPOS_ADR2 A S text 50 string 50 character 50 50 character 50 
REPOS_ADR3 A S text 50 string 50 character 50 50 character 50 
REPOS_CITY R S text 50 string 50 character 50 50 character 50 
REPOS_ST R S text 50 string 50 character 50 50 character 50 
REPOS_ZIP R S text 9 string 9 character 9 9 character 9 
IN_ID_DAT R S date/time 8 yyyymmdd 00/00/0000 date date 8 10 date 
IN_NFIP_DT R S date/time 8 yyyymmdd 00/00/0000 date date 8 10 date 
IN_FRM_DAT R S date/time 8 yyyymmdd 00/00/0000 date date 8 10 date 
RECENT_DAT A S date/time 8 yyyymmdd 00/00/0000 date date 8 10 date 

L-154


Table: L_Cst_Model 

This table is completed if coastal engineering analysis was performed. It is required for new 
coastal studies It is not required for digital conversions of effective flood hazard information 
because considerable additional effort may be required to research the applicable models. 

The L_Cst_Model table is a lookup table that contains information about the coastal models that 
were used during the engineering analysis. 

This is an Enhanced DFIRM Database table. 

The L_Cst_Model table contains the following elements. 

CST_MDL_ID R E Primary key for table lookup that links to the S_Cst_Tsct_Ln table. 
Value in this field should match the values in the CST_MDL_ID 
field of the S_Cst_Tsct_Ln table. 

WTR_NM_LID R E Surface Water Feature Name Lookup Identification. This is the 
name of the water feature that the model is associated with. The 
water feature name is taken from the table L_Wtr_Nm. This is a 
lookup table that is populated by the Mapping Partner that creates 
the database. 

CASE_NO R E Case Number Identification. This field is populated by a linking 
element to the L_Case_Info table. The L_Case_Info table contains 
information about the FEMA case number and includes archived 
electronic data that are relevant to the case. 

SURGE_LID R E Hurricane Surge Model Lookup Identification. This is the name or 
abbreviation of the Federal Emergency Management Agency 
(FEMA) approved hurricane surge model that is associated with the 
coastal engineering analysis. The surge model information is taken 
from the D_Surge_Mdl table. 

SURGE_DATE R E Hurricane Surge Model Run Date. This is the date the model was 
run. 

SURGE_ZIP R E Filename/path of zip file containing surge model input, surge model 
output, README.TXT, and any other supporting reports and 
documentation. 

SURGE_EFF R E Surge Effective Date. Effective date of the surge model. 

WAVEHT_LID A E Wave Height Model Lookup Identification. This is the name or 
abbreviation of the FEMA approved wave height model that was 
used for the coastal engineering analysis. The wave height model 
information is taken from the D_Wave_Mdl table. 


WAVEHT_DT A E Wave Height Model Run Date. This is the date the model was run. 

RUNUP_LID A E Runup Model Lookup Identification. This is the name or 
abbreviation of the FEMA approved wave runup model that was 
used for the coastal engineering analysis. The runup model 
information is taken from the D_Runup_Mdl table. 

RUNUP_DATE A E Runup Model Run Date. This is the date the wave runup model 
was run. 

SETUP_METH A E Wave Setup Methodology. This information should detail the 
methodology used for determining the wave setup magnitude. 

SETUP_DATE A E Wave Setup Methodology Date. This is the date the setup 
methodology was run. 

PFD_TF R E Have primary frontal dune criteria been applied in the coastal 
modeling? Enter "T" for true or "F" for false 

EROS_TF A E Has erosion treatment been applied in the coastal modeling? Enter 
T for true or F for false. 

WAVE_EFF A E Wave Effective Date. Effective date of the wave height and wave 
runup models. 

WAVE_ZIP A E File name/path of zip file containing wave height input, wave 
height output, wave runup input, wave runup output, 
README.TXT, and any other supporting reports and 
documentation. 


Table: L_Cst_Model

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
CST_MDL_ID R E text 11 string 11 character 11 11 character 11 
WTR_NM_LID R E text 11 string 11 character 11 11 character 11 
CASE_NO R E text 50 string 50 character 50 50 character 50 
SURGE_LID R E text 11 string 11 character 11 11 character 11 
SURGE_DATE R E date/time 8 yyyymmdd 00/00/0000 date date 8 10 date 
SURGE_ZIP R E text 254 string 254 character 254 254 character 254 
SURGE_EFF R E date/time 8 yyyymmdd 00/00/0000 date date 8 10 date 
WAVEHT_LID A E text 11 string 11 character 11 11 character 11 
WAVEHT_DT A E date/time 8 yyyymmdd 00/00/0000 date date 8 10 date 
RUNUP_LID A E text 11 string 11 character 11 11 character 11 
RUNUP_DATE A E date/time 8 yyyymmdd 00/00/0000 date date 8 10 date 
SETUP_METH A E text 100 string 100 character 100 100 character 100 
SETUP_DATE A E date/time 8 yyyymmdd 00/00/0000 date date 8 10 date 
PFD_TF R E text 1 string 1 character 1 1 character 1 

L-157


EROS_TF A E text 1 string 1 character 1 1 character 1 
WAVE_EFF A E date/time 8 yyyymmdd 00/00/0000 date date 8 10 date 
WAVE_ZIP A E text 254 string 254 character 254 254 character 254 

L-158


Table: L_Hydra_Model 

This table is only completed if detailed hydraulic engineering methods were used. It is required 
for new studies. 

The L_Hydra_Model table is a lookup table that contains detailed information about the 
hydraulic models used in the engineering analysis for the area. 

There should be one record for each distinct model run. 

This is an Enhanced DFIRM Database table. 

The L_Hydra_Model table contains the following elements. 

HYDRA_ID R S Hydraulic Model Identification. The primary key for table lookup 
that links to the L_XS_Ratings table. The value in this field should 
match the values in the HYDRA_ID field of the L_XS_Ratings 
table. 

HYDRA_LID R S Hydraulic Model Type Lookup Identification. Foreign key for table 
lookup that links to the D_Hydra table. 

HYDRA_DATE R S Hydraulic Model Run Date. This is the date that the hydraulic 
model was run. 

CASE_NO R S FEMA Case Number. This is the FEMA case number for the study. 
This ID may be used to link to the L_Case_Info table. 

HYDRA_ZIP R E Name of the Hydraulic Model Zipfile. This attribute stores the file 
name/pathway of the zipped file that contains the hydraulic model 
input and output data and any other auxiliary hydraulic data 
information. 


Table: L_Hydra_Model

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
HYDRA_ID R E text 11 string 11 character 11 11 character 11 
HYDRA_LID R E text 11 string 11 character 11 11 character 11 
HYDRA_DATE R E date/time 8 yyyymmdd 00/00/0000 date date 8 10 date 
CASE_NO R E text 12 string 12 character 12 12 character 12 
HYDRA_ZIP R E text 254 string 254 character 254 254 character 254 

L-160


Table: L_Hydro_Model 

This table is required for all studies with new or revised hydrologic data. 

The L_Hydro_Model table contains data specific to a particular hydrologic model used in the 
study. 

This is an Enhanced DFIRM Database table. 

The L_ Hydro_Model table contains the following elements. 

HYDRO_ID R E Hydrologic Model Identification. The primary key for table lookup 
that links to the L_Node_Disch table. 

HYDRO_LID R E Hydrologic Model Lookup Identification. A code that provides a 
link to a valid entry from the D_Hydro table. 

HYDRO_DATE R E Hydrologic Model Run Date. This is the date that the hydrologic 
model was run. 

CASE_NO R E FEMA Case Number. The case number for the hydrologic model 
links to the L_Case_Info table. 

HYDRO_ZIP R E Name of the Hydrologic Model Zipfile. The file name/pathway of 
the zipped file containing input & output files for hydrologic 
analysis and supporting data analyses. 


Table: L_Hydro_Model

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
HYDRO_ID R E text 11 string 11 character 11 11 character 11 
HYDRO_LID R E text 11 string 11 character 11 11 character 11 
HYDRO_DATE R E date/time 8 yyyymmdd 00/00/0000 date date 8 10 date 
CASE_NO R E text 12 string 12 character 12 12 character 12 
HYDRO_ZIP R E text 254 string 254 character 254 254 character 254 

L-162


Table: L_Media 

This table is required when digital photographs, sketches, or other media are used to describe 
spatial objects in the study. 

The L_Media table is a lookup table that links archived media to the spatial object represented in 
the photograph, sketch, or other media. 

This is an Enhanced DFIRM Database table. 

The L_Media table contains the following elements. 

MEDIA_ID R E Primary key for table lookup. Assigned by table creator. 

MEDIA_PATH R E The file name/relative path/location of the photograph, sketch, or 
other media. 

OBJ_TABLE R E Object Table. The DFIRM Database table that corresponds to the 
spatial object that the photograph, sketch, or other media describes. 

OBJ_ID R E Object Identification. The DFIRM Database primary key that 
corresponds to the spatial object that the photograph, sketch, or 
other media describes. Can be used as Foreign Key to object. 

MEDIA_TYPE R E Media Type. This is the type of media used to describe the object 
(e.g., Photo, Sketch, Video, etc.) 

MEDIA_DATE R E Media Date. This is the date on which the photograph, sketch, or 
other media was created. 

DSCRIPTION R E Description of the Object. This is a brief description of the object. 
It should include relevant directional information (e.g., Downstream 
face of Third Street bridge, Left bank of Big Creek, Along transect 
21 facing offshore). 

AZIMUTH A E Azimuth of a line that represents the line of sight from where the 
photographer was standing to the object. 0  360 degrees. 


Table: L_Media

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
MEDIA_ID R E text 11 string 11 character 11 11 character 11 
MEDIA_PATH R E text 254 string 254 character 254 254 character 254 
OBJ_TABLE R E text 20 string 20 character 20 20 character 20 
OBJ_ID R E text 11 string 11 character 11 11 character 11 
MEDIA_TYPE R E text 100 string 100 character 100 100 character 100 
MEDIA_DATE R E date/time 8 yyyymmdd 00/00/0000 date date 8 10 date 
DSCRIPTION R E text 254 string 254 character 254 254 character 254 
AZIMUTH A E text 100 string 100 character 100 100 character 100 

L-164


Table: L_MT1_LOMC 

The L_MT1_LOMC table is a lookup table that contains information about Letters of Map 
Change (LOMCs) for the area. LOMCs typically include property descriptions. Frequently, 
LOMCs are issued to show that specific locations are outside the Special Flood Hazard Areas 
(SFHAs). Generally, the amount of detail that can be shown on the map does not allow these 
areas to be shown explicitly on the Flood Insurance Rate Map (FIRM). Instead, this information 
is communicated in the form of a LOMC. For data published by the Federal Emergency 
Management Agency (FEMA), this table would only include letters of map amendment and 
letters of map revision based on fill that have been revalidated following the map revision. 
Revalidated LOMCs indicate that the information presented in the LOMC continues to be true 
regardless of the depiction of the area on the FIRM. 

For LOMCs that appear on more than one map panel, multiple records will exist with the same 
case number, but different panel numbers. 

This is a Standard DFIRM Database table. 

The L_MT1_LOMC table contains the following elements. 

LOMC_ID R S Primary key for table lookup. Assigned by table creator. 

CASE_NO R S Case Number. This is the case number assigned by FEMA to the 
LOMC. This should be filled in for reference back to the complete 
LOMC materials. The case number should be entered without 
hyphens or other separators. 

EFF_DATE R S Effective Date of the LOMC. 

FIRM_PAN R S FIRM panel number that the LOMC is on. This field provides a 
link to the S_FIRM_Pan table. MT1 LOMCs can be matched to a 
specific FIRM panel by matching this field to the FIRM_PAN field 
of the S_FIRM_Pan table. 

LOMC_STAT R S Status of the LOMC. Valid entries for this field include the 
following: 

superseded 

revalidated 

incorporated 
redetermined 

Only revalidated LOMCs are still in effect after a panel has been 
revised. All others should be superseded, redetermined or 
incorporated into the new FIRM. 


Table: L_MT1_LOMC

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
LOMC_ID R S text 11 string 11 character 11 11 character 11 
CASE_NO R S text 13 string 13 character 13 13 character 13 
EFF_DATE R S date/time 8 yyyymmdd 00/00/0000 date date 8 10 date 
FIRM_PAN R S text 11 string 11 character 11 11 character 11 
LOMC_STAT R S text 20 string 20 character 20 20 character 20 

L-166


Table: L_Node_Disch 

This table is required when hydrologic routing (flow combining) is used in the hydrologic 
analysis. For nodes whose subbasins are headwaters, this table will contain the same flow 
information as the subbasins outflow table.

L_Node_Disch is a lookup table that contains information regarding hydrologic routing.
A node may have none, one, or many links connected to it.
If an existing node is to be moved, it must be renamed.

This is an Enhanced DFIRM Database table.
The L_Node_Disch table contains the following elements.

FLOW_ID R E Primary key for this table. Assigned by table creator.

NODE_ID R E Node Identification. A code that links to the S_Nodes table.

NODE_LID R E Node Type Lookup Identification. A code that provides a link to 
the D_Nodes table. This field establishes the node type. Values 
include junction (default), reservoir, structure, and diversion. A 
junction node may have none, one, or many links connected to it. 

HYDRO_ID R E Hydrologic Model Identification. Link to the L_Hydro_Model 
table, which stores information about the hydrologic methods used 
in the study. 

FREQ_LID R E Frequency Interval Lookup Identification. A code that provides a 
link to the D_Frequency table. This attribute stores the return 
period for the associated discharge. 

DISCHARGE R E Discharge. Subbasin discharge/outflow for the above return period. 

DISCH_LID R E Discharge Unit Lookup Identification. A code that provides a link 
to a valid entry from the D_Discharge_Units table. 


Table: L_Node_Disch

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
FLOW_ID R E text 11 string 11 character 11 11 character 11 
NODE_ID R E text 11 string 11 character 11 11 character 11 
NODE_LID R E text 11 string 11 character 11 11 character 11 
HYDRO_ID R E text 11 string 11 character 11 11 character 11 
FREQ_LID R E text 11 string 11 character 11 11 character 11 
DISCHARGE R E text 11 string 11 character 11 11 character 11 
DISCH_LID R E text 11 string 11 character 11 11 character 11 

L-168


Table: L_Pan_Revis 

This table does not apply for an initial Flood Insurance Rate Map (FIRM) or for a FIRM that has 
a completely new paneling scheme, such as a first time countywide FIRM. Otherwise, this table 
is required for all draft Digital Flood Insurance Rate Map data. 

The L_Pan_Revis table is a lookup table that contains information about historic revisions to 
each FIRM panel. 

For each FIRM panel that is being revised, there should be at least one record. There may also 
be multiple records for multiple revision dates for a particular FIRM panel and there may be 
multiple records for a single revision date if there are multiple revision notes for that date. Each 
FIRM panel may have a unique set of revision dates and revision codes. There should be one 
record for each FIRM_PAN, REVIS_DATE, REVIS_NOTE combination. 

This is a Standard DFIRM Database table. 

The L_Pan_Revis table contains the following elements. 

REVIS_ID R S Primary key for table lookup. Assigned by table creator. 

FIRM_PAN R S FIRM Panel Number. This field links to the S_FIRM_Pan table. 
This should match a value in the FIRM_PAN field of the 
S_FIRM_Pan table. This is the complete FIRM panel number, 
which is made up of ST_FIPS, PCOMM, PANEL, and SUFFIX, 
which are found in S_FIRM_Pan table. The FIRM panel number is 
the 11-digit FIRM panel number that is shown in the title block of 
the map. 

REVIS_DATE R S Revision Date. Effective date of revision to the FIRM panel. 
FIRM revision dates can be found in the FIRM legend or the Flood 
Insurance Study (FIS) report. 

REVIS_NOTE R S Revision Note. Note describing the reason for the revision to the 
panel. This is shown under the effective date in the FIRM legend 
or in the FIS report. A list of standard revision notes appears in 
Appendix K of these Guidelines. 


Table: L_Pan_Revis

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
Type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
REVIS_ID R S text 11 string 11 character 11 11 character 11 
FIRM_PAN R S text 11 string 11 character 11 11 character 11 
REVIS_DATE R S date/time 8 yyyymmdd 00/00/0000 date date 8 10 date 
REVIS_NOTE R S text 254 string 254 character 254 254 character 254 

L-170


Table: L_Pol_FHBM 

This table does not apply if all communities on the FIRM never had revisions to their Flood 
Hazard Boundary Maps (FHBMs). Otherwise, this table is required for all Digital Flood 
Insurance Rate Map databases. 

The L_Pol_FHBM table is a lookup table that contains a list of communities and FHBM 
revisions. 

Each community may have different revision dates. Each revision date may have multiple 
revision notes. 

The L_Pol_FHBM table contains the following elements. 

FHBM_ID R S Primary key for table lookup. Assigned by table creator. 

CID R S Community Identification Number, which links to the S_Pol_Ar 
table. The value in this field should match a value in the CID field 
of the S_Pol_Ar table. This is the six-digit community 
identification number assigned by FEMA. It is created by including 
the state Federal Information Processing Standard or FIPS code 
with the COMM_NO. Only communities which have had a 
revision to their FHBM will appear in this table. 

FHBM_DATE R S FHBM revision date. 

FHBM_NOTE R S FHBM revision note that describes the reason for the revision. 
FHBM revision notes are shown in the Flood Insurance Rate Map 
legend or in the Flood Insurance Study report. A list of standard 
revision notes is included in Appendix K of these Guidelines. 


Table: L_Pol_FHBM

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
FHBM_ID R S text 11 string 11 character 11 11 character 11 
CID R S text 6 string 6 character 6 6 character 6 
FHBM_DATE R S date/time 8 yyyymmdd 00/00/0000 date date 8 10 date 
FHBM_NOTE R S text 254 string 254 character 254 254 character 254 

L-172


Table: L_Regression 

This table is required when regression equations are used in hydrologic analysis. 

L_Regression is a lookup table that stores information regarding the regression equations utilized 
in the hydrologic modeling. 

This is an Enhanced DFIRM Database table. 

The L_Regression table contains the following elements. 

REGR_ID R E Primary key for this table. Assigned by table creator. 

SUBBAS_ID R E Subbasin Identification. A code that provides a link to a valid entry 
from the S_Subbasins table. 

REGR_EQN R E Regression Equation. Regression equation used in the analysis. 
Non-Roman symbols (e.g., Greek) should be spelled out (e.g., Phi). 

REGR_RPT R E Regression Report. This field stores the name of the report in 
which the regression equation was published. 


Table: L_Regression

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
Type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
REGR_ID R E text 11 string 11 character 11 11 character 11 
SUBBAS_ID R E text 11 string 11 character 11 11 character 11 
REGR_EQN R E text 254 string 254 character 254 254 character 254 
REGR_RPT R E text 254 string 254 character 254 254 character 254 

L-174


Table: L_Stn_Start 

This table is required for any Digital Flood Insurance Rate Map database that has an S_XS or 
S_Riv_Mrk table. Because of production limitations, it may be omitted at the direction of the 
FEMA Project Officer. 

The L_Stn_Start table contains information about station starting locations. These locations 
indicate the reference point that was used as the origin for distance measurements along streams 
and rivers. This table is referenced by both the S_XS table, which contains stream station 
information for cross section, and by the S_Riv_Mrk table, which contains river distance marker 
points. The location of the stationing start for a group of cross sections is normally referenced as 
a note on the Floodway Data table and on the Flood Profiles. Generally, all of the cross sections 
for a particular reach are referenced to the same starting point. If multiple reaches are measured 
from the same point, they may share the same record in L_Stn_Start. 

This is a Standard DFIRM Database table. 

The L_Stn_Start table contains the following elements. 

START_ID R S Primary key for table lookup. Assigned by table creator. This field 
is the link that is used to reference cross section in the S_XS table 
or river marks in the S_Riv_Mrk table to the appropriate stationing 
starting point. 

START_DESC R S Start Description. The description of the location of the station 
starting point. This should include the measurement units. For 
example, Distances are measured in feet upstream from the 
confluence with the Main Channel of the Big River. 


Table: L_Stn_Start

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
START_ID R S text 11 string 11 character 11 11 character 11 
START_DESC R S text 254 string 254 character 254 254 character 254 

L-176


Table: L_Storm_Curve 

This table is required when precipitation data are used in the hydrologic analysis. 

The L_Storm_Curve table accommodates descriptions of Depth-Duration-Frequency (DDF) and 
Intensity-Duration-Frequency (IDF) relationships, as well as durations of e.g. design storms and 
precipitation patterns of historical storms. 

This is an Enhanced DFIRM Database table. 

The L_Storm_Curve table contains the following elements. 

CURVE_ID R E Primary key for this table. Assigned by table creator. 

STORM_ID R E Storm Identification. A code that provides a link to a valid entry 
from the L_Storm_Info table. 

DURATION R E Duration. Duration of precipitation event. The duration is that of a 
design or historical storm, or of a point on a DDF or IDF curve. 

TIME_LID R E Duration Unit Lookup Identification. A code that provides a link to 
a valid entry from the D_Time_Units table. This attribute 
establishes the unit of measure of the corresponding duration entry. 

DEPTH A E Precipitation Depth. This field is populated only if entering data for 
a DDF curve. 

LEN_LID A E Precipitation Depth Unit Lookup Identification. A code that 
provides a link to a valid entry from the D_Length_Units table. 
This attribute establishes the unit of measure for precipitation depth. 
This field is populated only if a precipitation depth is entered. 

INTENSITY A E Rainfall Intensity. This field is populated only if entering data for 
an IDF curve. 

VEL_LID A E Rainfall Intensity Unit Lookup Identification. A code that provides 
a link to a valid entry from the D_Velocity_Units table. This 
attribute establishes the unit of measure for precipitation intensity. 
This field is populated only if a precipitation intensity is entered. 

FREQ_LID A E Frequency Interval Lookup Identification. A code that provides a 
link to a valid entry from the D_Frequency table. This attribute 
stores the return period of the associated discharge. 


Table: L_Storm_Curve

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
Type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
CURVE_ID R E text 11 string 11 character 11 11 character 11 
STORM_ID R E text 11 string 11 character 11 11 character 11 
DURATION R E text 11 string 11 character 11 11 character 11 
TIME_LID R E text 11 string 11 character 11 11 character 11 
DEPTH A E 
number 
(double) 8 2 number 13 2 numeric 8 13 2 decimal 15 2 
LEN_LID A E text 11 string 11 character 11 11 character 11 
INTENSITY A E 
number 
(double) 8 2 number 13 2 numeric 8 13 2 decimal 15 2 
VEL_LID A E text 11 string 11 character 11 11 character 11 
FREQ_LID A E text 11 string 11 character 11 11 character 11 

L-178


Table: L_Storm_Info 

This table is required when precipitation distributions are used in the hydrologic analysis. 

The L_Storm_Info table is a lookup table that contains basic descriptions of precipitation 
patterns. 

This is an Enhanced DFIRM Database table.
The L_Storm_Info table contains the following elements.
STORM_ID R E Primary key for this table. Assigned by table creator.

STORM_LID R E Storm Type Lookup Identification. A code that provides a link to a 
valid entry from the D_Storms table. This attribute establishes the 
storm type. 

STORM_DESC A E Storm Description. Brief text description/note for the storm. 

SUBBAS_ID R E Subbasin Identification. A code that provides a link to a valid entry 
from the S_Subbasins table. 


Table: L_Storm_Info

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
STORM_ID R E text 11 string 11 character 11 11 character 11 
STORM_LID R E text 11 string 11 character 11 11 character 11 
STORM_DESC A E text 254 string 254 character 254 254 character 254 
SUBBAS_ID R E text 11 string 11 character 11 11 character 11 

L-180


Table: L_Subbas_Disch 

This table is required for all studies with new or revised non-coastal hydrologic data. 

The L_Subbas_Disch table is a lookup table that contains outflow data for each subbasin and 
recurrence interval in the hydrologic analysis. The subbasin outflow data is specific to that 
subbasin and must not be a cumulative system flow. (System flows, if required, are assigned in 
L_Node_Disch.). 

This is an Enhanced DFIRM Database table. 

The L_ Subbas_Disch table contains the following elements.
DISCH_ID R E Primary key for this table. Assigned by table creator.

SUBBAS_ID R E Subbasin Identification. A code that provides a link to a valid entry 
from the S_Subbasins table. 

FREQ_LID R E Frequency Interval Lookup Identification. A code that provides a 
link to a valid entry from the D_Frequency table. This attribute 
stores the return period for the associated discharge. 

DISCHARGE R E Discharge. Subbasin discharge/outflow for the above return period. 

DISCH_LID R E Discharge Unit Lookup Identification. A code that provides a link 
to a valid entry from the D_Discharge_Units table. 


Table: L_Subbas_Disch

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
DISCH_ID R E text 11 string 11 character 11 11 character 11 
SUBBAS_ID R E text 11 string 11 character 11 11 character 11 
FREQ_LID R E text 11 string 11 character 11 11 character 11 
DISCHARGE R E 
number 
(double) 8 2 number 13 2 numeric 8 13 2 decimal 15 2 
DISCH_LID R E text 11 string 11 character 11 11 character 11 

L-182


Table: L_Wtr_Nm 

The L_Wtr_Nm table is a lookup table that contains the name of the surface water feature shown 
on the Flood Insurance Rate Map (FIRM) and referenced throughout the database. This table is 
required if the draft Digital Flood Insurance Rate Map table structure is used. 

This is a Standard DFIRM Database table. 

The L_Wtr_Nm table contains the following elements. 

WTR_NM_LID R S Surface Water Feature Name Lookup Identification. The primary 
key that links to the S_Gen_Struct table, S_Wtr_Ar table, 
S_Wtr_Ln table, and S_XS table. This value should match the 
value in the WTR_NM_LID field for related records in these tables. 

WTR_NM R S Surface Water Feature Name. This is the formal name of the 
surface water feature, as it will appear on the hardcopy FIRM. 


Table: L_Wtr_Nm

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
WTR_NM_LID R S text 11 string 11 character 11 11 character 11 
WTR_NM R S text 100 string 100 character 100 100 character 100 

L-184


Table: L_XS_Ratings 

This table is required for a detailed study. 

The L_XS_Ratings table is a lookup table that contains information about the cross sections. 
This table should contain a record for each frequency / scenario associated with a cross section. 
For instance, if a cross section has data for the 25-, 100-and 500-year recurrence intervals, the 
L_XS_Ratings table should have three associated records. Therefore, each cross section should 
be associated with at least one record in L_XS_Ratings. The L_XS_Ratings table should possess 
at least one record at all times: the data for the 100-year regulatory model. 

This is an Enhanced DFIRM Database table. 

The L_XS_Ratings table contains the following elements. 

XS_RATG_ID R E Primary key for table lookup. Assigned systematically by the 
creator. 

XS_LN_ID R E Foreign key for table lookup that links to the S_XS table. Value in 
this field should match the values in the XS_LN_ID field of the 
S_XS table. 

XS_NO R E Cross Section Number. This attribute is used for all cross sections 
that are created during the engineering analysis. This must be 
populated with the number associated with the cross section used by 
the Mapping Partner in their modeling of the stream. 

REACH_NM A E Reach Name. This attribute stores that name of the reach in the 
model that the cross section intersects. XS_NO and REACH_NM 
may be used in conjunction as a unique identifier to identify the 
correct cross section in the model zipfile. This field is not 
populated if the correct cross section may be identified in the model 
without merging XS_NO and REACH_NM. 

FREQ_LID R E Frequency Interval Lookup Identification. A code that provides a 
link to the D_Frequency table. This field identifies the hydraulic 
analysis that applies to this record. Hydraulic analysis can be a 
recurrence interval (e.g., 1 percent or 0.2 percent flood hazard) or a 
scenario, for example without levee or with floodway. This ID is 
taken from the D_Frequency table. D_Frequency is a lookup table 
that is populated by the Mapping Partner that creates the database. 

FREQ_WSEL R E Water Surface Elevation. This is the water surface elevation 
associated with the frequency or scenario identified in FREQ_LID. 

LEN_LID R E Length Unit Lookup Identification. A code that provides a link to a 
valid unit of length from the D_Length_Units table. This unit 


indicates the measurement system used for the water surface 
elevation, stream bed elevation, and top width. 

V_DATM_LID R E Vertical Datum Lookup Identification. A code that provides a link 
to a valid vertical datum from the D_V_Datum table. The vertical 
datum indicates the reference surface from which the flood 
elevations are measured. Normally this would be North American 
Vertical Datum of 1988 for new studies. 

FREQ_Q A E Discharge Value. This is the discharge value associated with the 
frequency or scenario identified in FREQ_LID. This field is 
required when the frequency or scenario identified is based on a 
discharge value. For example, it is not required for stage gage 
analysis on rivers near the coast. 

DISCH_LID A E Discharge Unit Lookup Identification. A code that provides a link 
to a valid discharge unit in the D_Discharge_Units table. This unit 
specifies the unit of measurement for the discharge. This field is 
populated only if a discharge value is entered. 

HYDRA_ID R E Hydraulic Model Identification. A code that provides a link to the 
hydraulic model table, L_Hydra_Model. The L_Hydra_Model 
table will identify the hydraulic model used to calculate the flood 
hazard at this cross section line. This ID field must contain a 
number that matches the HYDRA_ID field for a record in the 
L_Hydra_Model table. The L_Hydra_Model table documents 
model information for this cross section. Multiple cross sections 
may link to a single record in the L_Hydra_Model table. 

HYDRO_ID R E Hydrologic Model Identification. A code that provides a link to the 
hydrologic model table, L_Hydro_Model. The L_Hydro Model 
table will identify the hydrologic model used to calculate the flood 
hazard at this cross section line. This ID field for a record in the 
L_Hydro_Model table. The L_Hydro_Model table documents 
model information for this cross section. Multiple cross sections 
may link to a single record in the L_Hydro_Model table. 

EFF_MODELS R E Effective Hydraulic and Hydrologic Model. This field is true only 
if the elevation and discharge are the result of the effective 
hydraulic and hydrologic models at this cross section. Enter T 
for true or F for false. 


Table: L_XS_Ratings

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
XS_RATG_ID R E text 11 string 11 character 11 11 character 11 
XS_LN_ID R E text 11 string 11 character 11 11 character 11 
XS_NO R E text 12 string 12 character 12 12 character 12 
REACH_NM A E text 254 string 254 character 254 254 character 254 
FREQ_LID R E text 11 string 11 character 11 11 character 11 
FREQ_WSEL R E 
number 
(double) 8 2 number 8 2 numeric 8 13 2 decimal 15 2 
LEN_LID R E text 11 string 11 character 11 11 character 11 
V_DATM_LID R E text 11 string 11 character 11 11 character 11 
FREQ_Q A E 
number 
(double) 8 2 number 8 2 numeric 8 13 2 decimal 15 2 
DISCH_LID A E text 11 string 11 character 11 11 character 11 
HYDRA_ID R E text 11 string 11 character 11 11 character 11 
HYDRO_ID R E text 11 string 11 character 11 11 character 11 

L-187


EFF_MODELS R E text 1 string 1 character 1 1 character 1 

L-188


Table: D_Area_Units 

The D_Area_Units table lists valid units for area measurement.

This is an Enhanced DFIRM Database table.
The D_Area_Units table contains the following elements.

AREA_LID Primary key for lookup table that links to various proposed enhanced 
tables. 

AREA_UNIT Unit of Area Measurement. Varies depending on the variable that it is 
quantifying. 

Table structure is shown below. Valid entries are shown in Section L.9. 


Table: D_Area_Units

Field S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
AREA_LID E text 11 string 11 character 11 11 character 11 
AREA_UNIT E text 20 string 20 character 20 20 character 20 

L-190


Table: D_CBRS_Typ 

The D_CBRS_Typ table lists valid types of Coastal Barrier Resources System (CBRS) areas. 

This is a Standard DFIRM Database table. 

The D_CBRS_Typ table contains the following elements. 

CBRS_LID Primary key for table lookup that links to the S_CBRS table. 

CBRS_TYP CBRS Type. The type code provides details of the types of prohibitions 
that apply to the area. 

Table structure is shown below. Valid entries are shown in Section L.9. 


Table: D_CBRS_Typ

Field S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
CBRS_LID S text 11 string 11 character 11 11 character 11 
CBRS_TYP S text 35 string 35 character 35 35 character 35 

L-192


Table: D_Chan_Rep 

The D_Chan_Rep table lists valid channel representations.

This is a Standard DFIRM Database table.
The D_Chan_Rep table contains the following elements.

CHAN_LID Primary key for table lookup that links to the S_Wtr_Ln table.

CHAN_REP Channel Representation. Single means linear water features represented 
by a centerline. Double means linear water features represented by 
shorelines or channel banks. 

Table structure is shown below. Valid entries are shown in Section L.9. 


Table: D_Chan_Rep

Field S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
CHAN_LID S text 11 string 11 character 11 11 character 11 
CHAN_REP S text 20 string 20 character 20 20 character 20 

L-194


Table: D_Discharge_Units 

The D_Discharge_Units table lists valid units for discharge measurement.

This is an Enhanced DFIRM Database table.
The D_Discharge_Units table contains the following elements.

DISCH_LID Primary key for lookup table that links to various proposed enhanced 
tables. 

DISCH_UNIT Unit of Discharge Measurement. Varies depending on the variable that it 
is quantifying. 

Table structure is shown below. Valid entries are shown in Section L.9. 


Table: D_Discharge_Units

Field S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
DISCH_LID E text 11 string 11 character 11 11 character 11 
DISCH_UNIT E text 20 string 20 character 20 20 character 20 

L-196


Table: D_Eros_Method 

The D_Eros_Method table lists the valid options for identifying the type of erosion methodology 
applied in areas where the dune feature along a ground profile is eroded to its storm profiles 
before coastal flood hazards are modeled. The options of removal and retreat are consistent with 
accepted FEMA methodologies and are related to the volume of sand lost/moved due to storm-
induced erosion. If erosion methodology was not applied to the modeling, the valid entry in the 
table is NOT APPLIED. 

This is an Enhanced DFIRM Database table.
The D_Eros_Method table contains the following elements.

EROS_LID Primary key for table lookup that links to the L_Cst_Model table.
EROS_METH Erosion Methodology. 
Table structure is shown below. Valid entries are shown in Section L.9. 


Table: D_Eros_Method

Field S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
EROS_LID E text 11 string 11 character 11 11 character 11 
EROS_METH E text 15 string 15 character 15 15 character 15 

L-198


Table: D_Floodway 

The D_Floodway table lists valid floodway representations. 

This is a Standard DFIRM Database table. 

The D_Floodway table contains the following elements. 

FLDWAY_LID Primary key for table lookup that links to the S_Fld_Haz_Ar table. 

FLOODWAY Floodway Type. Floodway areas are designated by the Federal 
Emergency Management Agency to provide an area that must be kept free 
of encroachment so that the 1-percent-annual-chance flood event can be 
carried without substantial increase in flood heights. Normal floodway 
areas are floodway. Special cases will have a note on the hardcopy 
Flood Insurance Rate Map. 

Table structure is shown below. Valid entries are shown in Section L.9. 


Table: D_Floodway

Field S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
FLDWAY_LID S text 11 string 11 character 11 11 character 11 
FLOODWAY S text 30 string 30 character 30 30 character 30 

L-200


Table: D_Frequency 

The D_Frequency table lists valid frequency interval types. This table is not intended to restrict 
the recurrence intervals or scenarios for which the creator may provide data. Rather, this table is 
intended to demonstrate how the frequency interval values and scenarios should be handled. 

This is an Enhanced DFIRM Database table. 

The D_Frequency table contains the following elements. 

FREQ_LID Primary key for table lookup that links to the L_XS_Ratings, 
L_Subbas_Disch, L_Storm_Info, and L_Node_Flow tables. 

FREQUENCY Frequency. This type code provides the recurrence interval or scenario of 
the associated cross section, subbasin, node, or storm. 

Cross sections that are associated with levees possess frequency values in FREQUENCY that 
indicate the behavior of the levee during the flood event. All levee related entries possess the 
word LEVEE in the value. In addition, the behavior of the levee is denoted with values for 
failure. For instance, a cross section that has a levee that does not fail during the 1 percent 
annual chance flood hazard event would possess 1 PCT LEVEE as its frequency value. That 
same cross section could also possess a frequency value, such as 1 PCT LEVEE, RIGHT 
FAILED, that indicates that the levee on the right side has failed. 

For the 1 percent flood annual chance flood hazard, the cross sections water surface elevation 
and discharge may be associated with a floodway or without a floodway. If the cross section is 
associated with a floodway, the water surface elevation value and discharge value for the 1 
percent flood hazard event should be entered in XS_WSEL and XS_Q in the L_XS_Ratings 
table, respectively. To indicate that the frequency is associated with floodway values, 1 PCT 
WITH FLOODWY should be used as the frequency value in D_Frequency. The water surface 
elevation value and discharge value for the 1 percent flood event without a floodway for the 
same cross section should be entered in XS_WSEL and XS_Q in the L_XS_Ratings table, 
respectively. To indicate that the frequency is associated with the without floodway values, 1 
PCT WITHOUT FLOODWAY should be used as the frequency value in D_Frequency. 

Example entries are shown in the table below. Additional entries may be added as needed to 
accommodate the scenarios modeled. 

Table structure is shown below. Valid entries are shown in Section L.9. 


Table: D_Frequency

Field S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
FREQ_LID E text 11 string 11 character 11 11 character 11 
FREQUENCY E text 100 string 100 character 100 100 character 100 

L-202


Table: D_Gage 

The D_Gage table lists valid gage types. 

This is an Enhanced DFIRM Database table. 

The D_Gage table contains the following elements. 

GAGE_LID Primary key for table lookup that links to the S_Precip_Gage, 
S_Water_Gage, and S_Cst_Gage tables. 

GAGE_TYPE Gage Type. The type of data the gage records. 

Table structure is shown belo w. Valid entries are shown in Section L.9. 


Table: D_Gage

Field S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
GAGE_LID E text 11 string 11 character 11 11 character 11 
GAGE_TYPE E text 40 string 40 character 40 40 character 40 

L-204


Table: D_Hydra 

The D_Hydra table lists valid hydraulic models. 

This is an Enhanced DFIRM Database table. 

The D_Hydra table contains the following elements. 

HYDRA_LID Primary key for table lookup that links to the L_Riv_Model table. 

HYDRA_MDL Hydraulic Model. This is the name or abbreviation of the hydraulic model 
that was used for the engineering analysis. As the Federal Emergency 
Management Agency approves the use of new engineering models for use 
in developing Flood Insurance Rate Maps, this list can be expanded. 

Table structure is shown below. Valid entries are shown in Section L.9. 


Table: D_Hydra

Field S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
HYDRA_LID E text 11 string 11 character 11 11 character 11 
HYDRA_MDL E text 40 string 40 character 40 40 character 40 

L-206


Table: D_Hydro 

The D_Hydro table lists valid hydrologic models. 

This is an Enhanced DFIRM Database table. 

The D_Hydro table contains the following elements. 

HYDRO_LID Primary key for table lookup that links to the L_Riv_Model table. 

HYDRO_MDL Hydrologic Model. This is the name or abbreviation of the hydrologic 
model that was used for the engineering analysis. As the Federal 
Emergency Management Agency approves the use of new engineering 
models for use in developing Flood Insurance Rate Maps, this list can be 
expanded. 

Table structure is shown below. Valid entries are shown in Section L.9. 


Table: D_Hydro

Field S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
HYDRO_LID E text 11 string 11 character 11 11 character 11 
HYDRO_MDL E text 40 string 40 character 40 40 character 40 

L-208


Table: D_Label_Typ 

The D_Label_Typ table lists valid features to which the labels and leaders apply. 

This is a Standard DFIRM Database table. 

The D_Label_Typ table contains the following elements. 

LABEL_LID Primary key for table lookup that links to the S_Label_Pt and the 
S_Label_Ld table. 

LABEL_TYPE Label type. This is a description of the planimetric features to which the 
labels and leaders are associated. For vector based maps, the labels and 
leaders will be associated with vector features in S_Trnsport_Ln, 
S_Wtr_Ar and S_Wtr_Ln. For maps with an ortho-photo base, the labels 
and leaders will be associated with DOQ water and transportation features. 
For maps that use both vector features and ortho-photos, all values may 
apply. 

Table structure is shown below. Valid entries are shown in Section L.9. 


Table: D_Label_Typ

Field S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
LABEL_LID S text 11 string 11 character 11 11 character 11 
LABEL_TYPE S text 20 string 20 character 20 20 character 20 

L-210


Table: D_Length_Units 

The D_Length_Units table lists valid units of measurement for length, elevation, height, or 
distance used throughout the database. 

This is a Standard and Enhanced DFIRM Database table. 

The D_Length_Units table contains the following elements. 

LEN_LID Primary key for table lookup that links to the S_BFE table, the 
S_Cst_Tsct_Ln table, the S_Fld_Haz_Ar table, the S_XS table, the 
L_Storm_Curve table and the L_XS_Ratings table. 

LEN_UNIT Unit of Length Measurement. Varies depending on the variable that it is 
quantifying. 

Table structure is shown below. Valid entries are shown in Section L.9. 


Table: D_Length_Units

Field S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
LEN_LID S & E text 11 string 11 character 11 11 character 11 
LEN_UNIT S & E text 20 string 20 character 20 20 character 20 

L-212


Table: D_Ln_Typ 

The D_Ln_Typ table lists valid line types used to determine symbology and drawing order on 
the hardcopy Flood Insurance Rate Map. 

This is a Standard DFIRM Database table. 

The D_Ln_Typ table contains the following elements. 

LN_LID Primary key for table lookup that links to the S_Fld_Haz_Ln table, the 
S_PLSS_Ln table, and the S_Pol_Ln table. Values 1000 thru 1999 are 
reserved for political lines, values 2000 thru 2999 are reserved for flood 
hazard lines, and values 3000 thru 3999 are reserved for U.S. Public Lands 
Survey System (PLSS) lines. 

LN_TYP Line Type. This is the boundary line type such as a floodplain boundary 
line, political boundary line, or PLSS boundary line. NOTE: The symbol 
% is a reserved symbol in most software packages so the word percent 
was abbreviated to PCT. 

Some lines may have multiple values. For the S_Pol_Ln table, the following precedence should 
apply: INTERNATIONAL, STATE, COUNTY, CORPORATE, EXTRATERRITORIAL 
JURISDICTION, URBAN GROWTH BOUNDARY, MUNICIPAL URBAN DRAINAGE 
DISTRICT, LEVEE IMPROVEMENT DISTRICT, AREA NOT INCLUDED, 
RESERVATION, FOREST, and PARK. 

For the S_Fld_Haz_Ln table, the following precedence should apply: LIMIT OF DETAILED 
STUDY, LIMIT OF STUDY, LIMIT OF FLOODWAY, FLOODWAY, 1 PCT ANNUAL-
CHANCE FLOOD HAZARD, ZONE BREAK, 0.2 PCT ANNUAL CHANCE FLOOD 
HAZARD, FLOWAGE EASEMENT BOUNDARY, and STATE ENCHROACHMENT LINE. 

The FEMA flood maps divide areas with 1 percent annual chance of flooding into more specific 
types of flood zones based on the characteristics of potential flooding in each area. Additionally, 
they divide areas of the same flood zone based on differences in base flood elevation, depth, or 
velocity. The 1 PERCENT ANNUAL CHANCE FLOOD HAZARD line type should also be 
used for the external boundaries of the 1 percent annual chance flood hazard areas. The ZONE 
BREAK line type should be used between different 1 percent annual chance flood hazard areas 
(e.g., between A and AE or AE and VE zones) and between areas of the same flood zone but 
different elevation, depth, or velocity. 

For the S_PLSS_Ln table, the following precedence should apply: TOWNSHIP, RANGE, 
SECTION, QUARTER SECTION, and MEANDER. 

Table structure is shown below. Valid entries are shown in Section L.9. 


Table: D_Ln_Typ

Field S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
LN_LID S text 11 string 11 character 11 11 character 11 
LN_TYP S text 45 string 45 character 45 45 character 45 

L-214


Table: D_Method 

The D_Method table lists the valid options for describing the general methodology used in 
deriving the station and elevation point data along transects used in modeling coastal flood 
hazards. 

This is an Enhanced DFIRM Database table.
The D_Method table contains the following elements.
METH_LID Primary key for table lookup that links to the S_Cst_Tsct_Ln table.

METHOD Survey method used to locate transect points. 
Table structure is shown below. Valid entries are shown in Section L.9.


Table: D_Method

Field S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
METH_LID E text 11 string 11 character 11 11 character 11 
METHOD E text 20 string 20 character 20 20 character 20 

L-216


Table: D_Nm_Typ 

The D_Nm_Typ table lists valid transportation feature name types.
This is a Standard DFIRM Database table.
The D_Nm_Typ table contains the following elements.
NM_LID Primary key for table lookup that links to the S_Trnsport_Ln table.
NM_TYP Name Type. The transportation feature name type.
Table structure is shown below. Valid entries are shown in Section L.9.


Table: D_Nm_Typ

Field S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
NM_LID S text 11 string 11 character 11 11 character 11 
NM_TYP S text 20 string 20 character 20 20 character 20 

L-218


Table: D_Nodes 

The D_Nodes table lists valid node types. 

This is an Enhanced DFIRM Database table. 

The D_Nodes table contains the following elements. 

NODE_LID Primary key for table lookup that links to the S_Nodes table. 

NODE_TYPE The type of hydrologic network point that the node represents. The 
default node type is a junction. 

Table structure is shown below. Valid entries are shown in Section L.9. 


Table: D_Nodes

Field S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
NODE_LID E text 11 string 11 character 11 11 character 11 
NODE_TYPE E text 10 string 10 character 10 10 character 10 

L-220


Table: D_Panel_Typ 

The D_Panel_Typ table lists valid Flood Insurance Rate Map (FIRM) panel types.

This is a Standard DFIRM Database table.
The D_Panel_Typ table contains the following elements.

PANEL_LID Primary key for table lookup that links to the S_FIRM_Pan table.

PANEL_TYP Panel Type. The type of FIRM panel that identifies whether the panel is 
printed or not printed and whether it is community based or countywide 
mapping. 

Table structure is shown below. Valid entries are shown in Section L.9. 


Table: D_Panel_Typ

Field S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
PANEL_LID S text 11 string 11 character 11 11 character 11 
PANEL_TYP S text 35 string 35 character 35 35 character 35 

L-222


Table: D_Rd_Stat 

The D_Rd_Stat table lists valid road status values.
This is a Standard DFIRM Database table.
The D_Rd_Stat table contains the following elements.
RD_S_LID Primary key for table lookup that links to the S_Trnsport_Ln table.
RD_STAT Road Status. 
Table structure is shown below. Valid entries are shown in Section L.9.


Table: D_Rd_Stat

Field S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
RD_S_LID S text 11 string 11 character 11 11 character 11 
RD_STAT S text 20 string 20 character 20 20 character 20 

L-224


Table: D_Runup_Mdl 

The D_Runup_Mdl table lists valid wave runup models that can be used for the engineering 
analysis. 

This is an Enhanced DFIRM Database table. 

The D_Runup_Mdl table contains the following elements. 

RUNUP_LID Primary key for table lookup that links to the L_Cst_Model table. 

RUNUP_MDL Runup Model. This is the name or abbreviation of the wave runup model 
that was used for the engineering analysis. As the Federal Emergency 
Management Agency approves the use of new engineering models for use 
in developing FIRMs, this list can be expanded. 

Table structure is shown below. Valid entries are shown in Section L.9. 


Table: D_Runup_Mdl

Field S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
RUNUP_LID E text 11 string 11 character 11 11 character 11 
RUNUP_MDL E text 30 string 30 character 30 30 character 30 

L-226


Table: D_Scale 

The D_Scale table lists valid Flood Insurance Rate Map (FIRM) scales, ratios. 

This is a Standard DFIRM Database table. 

The D_Scale table contains the following elements. 

SCALE_LID Primary key for table lookup that links to the S_FIRM_Pan table and the 
S_LOMR table. 

SCALE Map Scale. This is the denominator of the FIRM scale or effective Letter 
of Map Revision scale as a ratio. For example, 24000 is the denominator 
for a 1 = 2000 map. 

Table structure is shown below. Valid entries are shown in Section L.9. 


Table: D_Scale

Field S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
SCALE_LID S text 11 string 11 character 11 11 character 11 
SCALE S text 5 string 5 character 5 5 character 5 

L-228


Table: D_Shr_Rough 

The D_Shr_Rough table provides the valid shoreline type. 

This is an Enhanced DFIRM Database table. 

The D_Shr_Rough table contains the following elements. 

SHR_LID Primary key for table lookup that links to the S_Cst_Tsct_Ln table. 

SHR_ROUGH Shoreline Roughness Type. The following lists the shoreline roughness 
type and a description of the shoreline types that are included in the 
classification: 

 Very Low: barrier beaches, sand beaches, salt marshes, mud flats, 
deltas, mangroves, coral reefs 
 Low: cobble beaches, estuaries, lagoons 
 Moderate: low cliffs, glacial drift, alluvial plains 
 High: medium cliffs, indented coasts 
 Very High: rocky, cliffed coasts, fiords 
Table structure is shown below. Valid entries are shown in Section L.9. 

Table: D_Shr_Rough

Field S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
SHR_LID E text 11 string 11 character 11 11 character 11 
SHR_ROUGH E text 10 string 20 character 20 20 character 20 

L-230


Table: D_Shr_Typ 

The D_Shr_Typ table lists valid criteria used in determining shorelines used in the coastal flood 
hazards model.

This is an Enhanced DFIRM Database table.

The D_Shr_Typ table contains the following elements. 
SHRTYP_LID Primary key for table lookup that links to the S_Shore_Ln table.
SHRLN_TYP Criteria used in determining shoreline.

Table structure is shown below. Valid entries are shown in Section L.9.


Table: D_Shr_Typ

Field S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
SHRTYP_LID E text 11 string 11 character 11 11 character 11 
SHRLN_TYP E text 30 string 30 character 30 30 character 30 

L-232


Table: D_Storms 

The D_Storms table lists valid types of storms. 

This is an Enhanced DFIRM Database table. 

The D_Storms table contains the following elements. 

STORM_LID Primary key for table lookup that links to the L_Storm_Info table. 

STORM_TYPE Storm Type. The type of precipitation distribution defined by the data 
records. 

Table structure is shown below. Valid entries are shown in Section L.9. 


Table: D_Storms

Field S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
STORM_LID E text 11 string 11 character 11 11 character 11 
STORM_TYPE E text 20 string 20 character 20 20 character 20 

L-234


Table: D_Struct_Typ 

The D_Struct_Typ table lists valid structure types associated with general hydraulic.
This is a Standard DFIRM Database table.
The D_Struct_Typ table contains the following elements.
STRUCT_LID Primary key for table lookup that links to the S_Gen_Struct table.
STRUCT_TYP Structure Type. These are hydraulic structures within the study area.
Table structure is shown below. Valid entries are shown in Section L.9.


Table: D_Struct_Typ

Field S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
STRUCT_LID S text 11 string 11 character 11 11 character 11 
STRUCT_TYP S text 36 string 36 character 36 36 character 36 

L-236


Table: D_Surge_Mdl 

The D_Surge_Mdl table lists valid hurricane surge models that can be used during the 
engineering analysis. 

This is an Enhanced DFIRM Database table. 

The D_Surge_Mdl table contains the following elements. 

SURGE_LID Primary key for table lookup that links to the L_Cst_Model table. 

SURGE_MDL Hurricane Surge Model. This is the name or abbreviation of the hurricane 
surge model that was used for the engineering analysis. As the Federal 
Emergency Management Agency approves the use of new engineering 
models for use in developing FIRMs; this list can be expanded. 

Table structure is shown below. Valid entries are shown in Section L.9. 


Table: D_Surge_Mdl

Field S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
SURGE_LID E text 11 string 11 character 11 11 character 11 
SURGE_MDL E text 40 string 40 character 40 40 character 40 

L-238


Table: D_Time_Units 

The D_Time_Units table lists valid units for time measurement.

This is an Enhanced DFIRM Database table.
The D_Time_Units table contains the following elements.

TIME_LID Primary key for lookup table that links to various proposed enhanced 
tables. 

TIME_UNIT Unit of Time Measurement. Varies depending on the variable that it is 
quantifying. 

Table structure is shown below. Valid entries are shown in Section L.9. 


Table: D_Time_Units

Field S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
TIME_LID E text 11 string 11 character 11 11 character 11 
TIME_UNIT E text 20 string 20 character 20 20 character 20 

L-240


Table: D_Trans_Typ 

The D_Trans_Typ table lists valid transportation feature types for base map features. 

This is a Standard DFIRM Database table. 

The D_Trans_Typ table contains the following elements. 

TRANS_LID Primary key for table lookup that links to the S_Trnsport_Ln table. 
Values 1000 thru 1999 are reserved for road types, values 2000 thru 2999 
are reserved for railroads, values 3000 thru 3999 are reserved for airports, 
and values 4000 thru 4999 are reserved for water transportation. 

TRANS_TYP Transportation Feature Type. 

The value UNDEFINED ROAD should only be used when it cannot be determined if the road 
feature is a primary or secondary road. The value UNDEFINED RAILROAD should only be 
used when it cannot be determined if the railroad feature is an active, abandoned, or dismantled 
railroad. 

Table structure is shown below. Valid entries are shown in Section L.9. 


Table: D_Trans_Typ

Field S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
TRANS_LID S text 11 string 11 character 11 11 character 11 
TRANS_TYP S text 50 string 50 character 50 50 character 50 

L-242


Table: D_V_Datum 

The D_V_Datum table lists valid vertical datums. 

This is a Standard and Enhanced DFIRM Database table. 

The D_V_Datum table contains the following elements. 

V_DATM_LID Primary key for table lookup that links to the S_BFE table, the 
S_Fld_Haz_Ar table, and the Study_Info table. 

V_DATUM Vertical Datum. North American Vertical Datum of 1988 (NAVD88) is 
preferred. However, older studies may have been prepared using the 
National Geodetic Vertical Datum of 1929 (NGVD29). 

Table structure is shown below. Valid entries are shown in Section L.9. 


Table: D_V_Datum

Field S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
V_DATM_LID S & E text 11 string 11 character 11 11 character 11 
V_DATUM S & E text 6 string 6 character 6 6 character 6 

L-244


Table: D_Velocity_Units 

The D_Velocity_Units table lists valid units for velocity measurement. 

This is a Standard and Enhanced DFIRM Database table. 
The D_Velocity_Units table contains the following elements. 

VEL_LID Primary key for table lookup that links to the S_Fld_Haz_ Ar table, the 
S_XS table, and the L_Storm_Curve table. 

VEL_UNIT Unit of Velocity Measurement. Varies depending on the variable that it is 
quantifying. 

Table structure is shown below. Valid entries are shown in Section L.9. 


Table: D_Velocity_Units

Field S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
VEL_LID S & E text 11 string 11 character 11 11 character 11 
VEL_UNIT S & E text 20 string 20 character 20 20 character 20 

L-246


Table: D_Volume_Units 

The D_Volume_Units table lists valid units for volume measurement.

This is an Enhanced DFIRM Database table.
The D_Volume_Units table contains the following elements.

VOL_LID Primary key for lookup table that links to various proposed enhanced 
tables. 

VOL_UNIT Unit of Volume Measurement. Varies depending on the variable that it is 
quantifying. 

Table structure is shown below. Valid entries are shown in Section L.9. 


Table: D_Volume_Units

Field S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
VOL_LID E text 11 string 11 character 11 11 character 11 
VOL_UNIT E text 20 string 20 character 20 20 character 20 

L-248


Table: D_VZone 

The D_VZone table lists the valid options for classifying the landward extent of the V Zone 
along a coastal transect. This information provides a brief summary to users about the 
predominating methodology that was used to determine the landward extent of the V Zone 
shown in the mapped flood hazard areas. 

This is an Enhanced DFIRM Database table. 

The D_VZone table contains the following elements. 

VZONE_LID Primary key for table lookup that links to the S_Cst_Ln table. 

VZONE_EXT V Zone Extent. This is the predominating methodology that was used to 
determine the landward extent of the V Zone shown in the mapped flood 
hazard areas. 

Table structure is shown below. Valid entries are shown in Section L.9. 


Table: D_VZone

Field S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
VZONE_LID E text 11 string 11 character 11 11 character 11 
VZONE_EXT E text 40 string 40 character 40 40 character 40 

L-250


Table: D_Water_Typ 

The D_Water_Typ table lists valid water feature types. 

This is a modified Standard DFIRM Database domain table that includes Standard DFIRM 
Database domain values and Enhanced DFIRM Database domain values. 

The D_Water_Typ table contains the following elements. 

WATER_LID Primary key for table lookup that links to the S_Profil_Basln table, 
S_Wtr_Ar table, and the S_Wtr_Ln table. 

WATER_TYP Surface Water Feature Type. 

Table structure is shown below. Valid entries are shown in Section L.9. 


Table: D_Water_Typ

Field S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
WATER_LID S & E text 11 string 11 character 11 11 character 11 
WATER_TYP S & E text 40 string 40 character 40 40 character 40 

L-252


Table: D_Wave_Mdl 

The D_Wave_Mdl table lists valid wave height models used during the coastal engineering 
analysis. 

This is an Enhanced DFIRM Database table. 

The D_Wave_Mdl table contains the following elements. 

WAVEHT_LID Primary key for table lookup that links to the L_Cst_Model table. 

WAVEHT_MDL Wave Height Model. This is the name or abbreviation of the wave height 
model that was used for the coastal engineering analysis. As the Federal 
Emergency Management Agency approves the use of new engineering 
models for use in developing FIRMs; this list can be expanded. 

Table structure is shown below. Valid entries are shown in Section L.9. 


Table: D_Wave_Mdl

Field S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
WAVEHT_LID E text 11 string 11 character 11 11 character 11 
WAVEHT_MDL E text 25 string 25 character 25 25 character 25 

L-254


Table: D_Zone 

The D_Zone table lists valid Flood Insurance Rate Map (FIRM) flood zones. 

This is a Standard DFIRM Database table. 

The D_Zone table contains the following elements. 

ZONE_LID Primary key for table lookup that links to the S_Fld_Haz_Ar table. 

FLD_ZONE Flood Zone. This is the flood insurance risk zone designation. These 
zones are used by the Federal Emergency Management Agency (FEMA) 
to designate Special Flood Hazard Areas (SFHAs) and for insurance rating 
purposes. Some older FEMA FIRMs were prepared in the Standard 
format that uses Zones B, C and numbered A and V zones. Newer FIRMs 
use the Map Initiatives format where the B corresponds to 0.2 PCT 
ANNUAL CHANCE FLOOD HAZARD; C corresponds to Zone X; 
numbered A zones (e.g., A1, A2, A3) correspond to Zone AE; and 
numbered V zones (e.g., V1, V2, V3) correspond to Zone VE. All Digital 
Flood Insurance Rate Maps (DFIRMs) should use the Map Initiatives zone 
designations. See Volume 1, Subsection 1.4.6.1.5 of these Guidelines for 
details on the flood insurance risk zones. (NOTE: The symbol % is a 
reserved symbol in most software packages so the word percent was 
abbreviated as PCT.) 

Where the 1-percent-annual-chance flood or the 0.2-percent-annual-chance flood is contained in 
a culvert or channel, a corresponding feature appears in the S_Fld_Haz_Ar table only if an 
SFHA or 0.2-percent-annual-chance flood zone is shown on the FIRM in this area. In general, 
these culverts and channels are to be represented in the general structure table regardless of how 
the flood insurance risk zones are depicted. So, if these structures are shown on the FIRM as a 
dashed line passing through a Zone X, no corresponding flood insurance risk zone is shown in 
S_Fld_Haz_Ar table in the DFIRM database. If a narrow SFHA or 0.2-percent-annual-chance 
flood zone is shown on the FIRM, then a narrow polygon must be included in the DFIRM 
database. If the width of this flood insurance risk zone is accurately known and represented in 
the spatial data, the normal flood insurance risk zone is applied. If the width of the flood 
insurance risk zone is not accurately known and represented because of scale limitations, then 
the zone is designated as 1-percent-annual-chance flood contained in channel or 0.2-percent-
annual-chance flood contained in channel as appropriate. 

Table structure is shown below. Valid entries are shown in Section L.9. 


Table: D_Zone

Field S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
ZONE_LID S text 11 string 11 character 11 11 character 11 
FLD_ZONE S text 55 string 55 character 55 55 character 55 

L-256


L.5 Federal Emergency Management Agency Digital 
Mapping Information Checklist 

Federal Emergency Management Agency Digital Mapping Information Checklist 

The following checklist is intended to solicit basic information about the format of digital 
mapping data submitted to the Federal Emergency Management Agency (FEMA) for preparation 
of a Digital Flood Insurance Rate Map (DFIRM). Please note that metadata compliant with the 
Federal Geographic Data Committees Content Standard for Digital Geospatial Metadata should 
be submitted also. This metadata must include the following information and further details 
about the data submitted. 

Point of Contact: 

Name and/or Title _______________________________________ 

Community/Agency _______________________________________ 

Department _______________________________________ 

Address _______________________________________ 

_______________________________________ 

Telephone _______________________________________ 

Fax _______________________________________ 

Email _______________________________________ 

Data Type: 

Pertinent information includes the following: 

Format: 
. ESRI Coverage 
. ESRI Shapefile 
. MapInfo 
. Intergraph 
. AutoCAD 
. Digital Line Graph 
. Other __________________________ 


. Digital Orthophoto 

. Scanned 

Source Information: 

Black & white
Color
TIF
JPEG
SID
PNG
Raw

Georeferenced? _____________________
Dots per inch _____________________
Black & white 

Grey scale 
Color 

How and when were the data compiled? 
includes the following: 

. Photogrammetrically compiled 
. Digitized from a hardcopy source 

. Parcel maps/Plat maps 

. USGS quadrangles 

. Orthophotos 

. Aerial photos 

. Other community map ___________________ 

By whom? At what scale? Pertinent information 

. Generated using coordinate geometry (COGO) 
. Scanned 

Date of photography or source material _________________________________
Scale of data creation _________________________________
Agency or firm that produced the data _________________________________

Date of creation (if incomplete, provide estimated completion date) ___________

Projection, Datums, Accuracy: 

What coordinate system and projection were used? What horizontal and vertical datums were 
used? What is the stated accuracy of the data? 


Coordinate system/projection: 
. State Plane 
. UTM 
. Geographic (latitude and longitude) 
. Other __________________ 

Units: 
. Feet 
. Meters 
. Decimal degrees 
. Degrees, minutes, seconds 
. Other __________________ 

Horizontal datum: 
. NAD27, Clarke 1866 spheroid 
. NAD83, GRS80 spheroid 

Vertical datum: 
. NGVD29 
. NAVD88 
. Other ______________________ 

Accuracy ______________________ 

Data Contents: 

What features are contained in the data set(s)? Are feature names included? If so, are they 
available as attributes and/or graphic text (annotation)? Please provide file structure details in 
the form of metadata, a data dictionary, or a layer list in addition to this form 

. Roads 

. Centerlines 

. Edge of pavement 

. Road names 
Scale(s) at which they were intended to be used ____________________ 
. Railroads 

. Railroad names 
. Airports 

. Airport names 

. Streams, lakes, other water bodies 

. Feature names 
. Range & township/section lines and numbers 


. Political boundaries 

. Area names 
. Flood control structures (dams, weirs, jetties, culverts, etc.) 

. Floodplain boundaries and/or other FIRM features 

. Contours 
Contour interval _______________________ 
. DEM/DTM/TIN 

. Building outlines 
. Parcels 

Transfer Media: 

What options are there for transferring the data to other users? What are the platform options? 

Media: 

. CD-ROM 

. 8mm tape 

. 4mm tape 

. Zip disk 

. Diskettes 
. DVD 

. Email 

. Other ____________________________ 
Platforms: 
. UNIX 

. PC 

. NT 


L.6 Metadata Example for Draft Digital Data 

DFIRM DATABASE, FLOOD COUNTY, USA 

Identification_Information: 
Citation: 
Citation_Information: 
Originator: FEMA Mapping Partner 
Publication_Date: 20000505 
Title: DIGITAL FLOOD INSURANCE RATE MAP DATABASE, FLOOD COUNTY, USA 

Publication_Information: 
Publication_Place: Washington, DC 
Publisher: Federal Emergency Management Agency 

Other_Citation_Details: Metadata_File_Name: 99009C_19980915_metadata.htm 
Online_Linkage: http://www.fema.gov/msc 
Description: 

Abstract: The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information 
and supporting data used to develop the risk data. The primary risk classifications used are the 1-
percent-annual-chance flood event, the 0.2-percent-annual-chance flood event, and areas of minimal 
flood risk. The DFIRM Database is derived from Flood Insurance Studies (FISs), previously 
published Flood Insurance Rate Maps (FIRMs), flood hazard analyses performed in support of the 
FISs and FIRMs, and new mapping data where available. The FISs and FIRMs are published by the 
Federal Emergency Management Agency (FEMA). The file is georeferenced to earth's surface using 
the UTM projection and coordinate system. The specifications for the horizontal control of DFIRM 
data files are consistent with those required for mapping at a scale of 1:12,000. 

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 Flood Disaster Protection Act of 1973). 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 coverage offered through the NFIP. 

The DFIRM Database presents the flood risk information depicted on the FIRM in a digital format 
suitable for use in electronic mapping applications. The DFIRM Database is a subset of the Digital 
FIS database that serves to archive the information collected during the FIS. 

Time_Period_of_Content: 
Time_Period_Information: 
Single_Date/Time: 

Calendar_Date: 19980701 

Currentness_Reference: FIRM and FIS Effective date 

Status: 
Progress: Complete 
Maintenance_and_Update_Frequency: Irregular 

Spatial_Domain: 
Bounding_Coordinates: 

West_Bounding_Coordinate: -84.125 
East_Bounding_Coordinate: -84.25 
North_Bounding_Coordinate: 30.5 
South_Bounding_Coordinate: 30.625 

Keywords: 
Theme: 


Theme_Keyword_Thesaurus: None
Theme_Keyword: FEMA Flood Hazard Zone
Theme_Keyword: DFIRM Database
Theme_Keyword: DFIRM
Theme_Keyword: Special Flood Hazard Area
Theme_Keyword: Digital Flood Insurance Rate Map
Theme_Keyword: CBRS
Theme_Keyword: Coastal Barrier Resources System
Theme_Keyword: Riverine Flooding
Theme_Keyword: Coastal Flooding
Theme_Keyword: NFIP
Theme_Keyword: Base Flood Elevation
Theme_Keyword: SFHA
Theme_Keyword: Flood Insurance Rate Map
Theme_Keyword: FIRM
Theme_Keyword: Floodway

Place: 
Place_Keyword_Thesaurus: None 

Place_Keyword: FLOOD COUNTY 
Place_Keyword: USA 

Access_Constraints: None 

Use_Constraints: The hardcopy FIRM and DFIRM maps and the accompanying FISs are the official 
designation of SFHAs and Base Flood Elevations (BFEs) for the NFIP. For the purposes of the NFIP, 
changes to the flood risk information published by FEMA may only be performed by FEMA and 
through the mechanisms established in the NFIP regulations (44 CFR Parts 59-78). 

These digital data are produced in conjunction with the hardcopy FIRMs and generally match the 
hardcopy map exactly. However the hardcopy flood maps and flood profiles are the authoritative 
documents for the NFIP. 

Acknowledgement of FEMA would be appreciated in products derived from these data. 
Point_of_Contact: 
Contact_Information: 

Contact_Organization_Primary: 

Contact_Organization: Mapping Partner Contact Name 
Contact_Position: Mapping Partner Position 
Contact_Address: 

Address_Type: mailing address 
Address: Mapping Partner Address 
City: Mapping Partner City 
State_or_Province: Mapping Partner State 
Postal_Code: Mapping Partner Zip 
Country: Mapping Partner Country 

Contact_Voice_Telephone: Mapping Partner Phone Number 

Contact_Electronic_Mail_Address: Mapping Partner Email 
Native_Data_Set_Environment: Description of Mapping Partners digital mapping environment 
Cross_Reference: 

Citation_Information: 
Originator: Federal Emergency Management Agency 

Publication_Date: 19980701
Title: Flood Insurance Rate Map, FLOOD COUNTY, USA

Geospatial_Data_Presentation_Form: map 

Publication_Information: 
Publication_Place: Washington, DC 
Publisher: Federal Emergency Management Agency 

Cross_Reference: 


Citation_Information: 
Originator: Federal Emergency Management Agency 

Publication_Date: 19980701
Title: Flood Insurance Study, FLOOD COUNTY, USA

Geospatial_Data_Presentation_Form: document 

Publication_Information: 
Publication_Place: Washington, DC 
Publisher: Federal Emergency Management Agency 

Cross_Reference: 

Citation_Information: 
Originator: Federal Emergency Management Agency 
Publication_Date: 19980701 
Title: Raster DFIRM, FLOOD COUNTY, USA 
Geospatial_Data_Presentation_Form: raster digital data 
Publication_Information: 

Publication_Place: Washington, DC 
Publisher: Federal Emergency Management Agency 
Data_Quality_Information: 
Attribute_Accuracy: 

Attribute_Accuracy_Report: The DFIRM Database consists of countywide vector files and 
associated attributes produced in conjunction with the hardcopy FEMA FIRMs. The published 
effective FIRM and DFIRM are issued as the official designation of the SFHAs. As such, they are 
adopted by local communities and form the basis for administration of the NFIP. For these purposes 
they are authoritative. Provisions exist in the regulations for public review, appeals and corrections 
of the flood risk information shown to better match real world conditions. As with any engineering 
analysis of this type, variation from the estimated flood heights and floodplain boundaries is 
possible. Details of FEMA's requirements for the FISs and flood mapping process that produces 
these data are available in the Guidelines and Specifications for Flood Hazard Mapping Partners. 
Attribute accuracy was tested by manual comparison of source graphics with hardcopy plots and a 
symbolized display on an interactive computer graphic system. 

Independent quality control testing of FEMAs DFIRM database was also performed. 

To obtain more detailed information in areas where Base Flood Elevations (BFEs) and/or 
floodways have been determined, users are encouraged to consult the Flood Profiles and Floodway 
Data and/or Summary of Stillwater Elevations tables contained within the FIS report that 
accompanies this DFIRM database. Users should be aware that BFEs shown in the S_BFE table 
represent rounded whole-foot elevations. These BFEs are intended for flood insurance rating 
purposes only and should not be used as the sole source of flood elevation information. 
Accordingly, flood elevation data presented in the FIS report should be used in conjunction with the 
FIRM for purposes of construction and/or floodplain management. The 1-percent-annual-chance 
water-surface elevations shown in the S_XS table match the regulatory elevations shown in the FIS 
report. 

Logical_Consistency_Report: When FEMA revises an FIS, adjacent studies are checked to ensure 
agreement between flood elevations at the boundaries of the studies. Like wise, flood elevations at the 
confluence of streams studied independently are checked to ensure agreement at the confluence. The 
FIRM and the FIS are developed together and care is taken to ensure that the elevations and other 
features shown on the flood profiles in the FIS agree with the information shown on the FIRM. 
However, the elevations as shown on the FIRM are rounded whole-foot elevations. They must be shown 
so that a profile recreated from the elevations on the FIRM will match the FIS profiles within one half of 
one foot. 

Completeness_Report: The data contained in the DFIRM Database files reflect the content of the source 
materials. Features may have been eliminated or generalized on the source graphic, due to scale and 
legibility constraints. With new mapping, FEMA plans to maintain full detail in the spatial data it 
produces. However, older information is often transferred from existing maps where some 
generalization has taken place. 


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 analyses of records of 
river flow, storm tides, and rainfall, information obtained through consultation with the communities, 
floodplain topographic surveys, and hydrological 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 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. 

Positional_Accuracy: 
Horizontal_Positional_Accuracy: 
Horizontal_Positional_Accuracy_Report: The DFIRM Database consists of countywide vector 
files and associated attributes produced in conjunction with the hard copy FEMA FIRMs. The 
published effective FIRM and DFIRM maps are issued as the official designation of the 
SFHAs. As such they are adopted by local communities and form the basis for administration 
of the NFIP. For these purposes they are authoritative. Provisions exist in the regulations for 
public review, appeals and corrections of the flood risk information shown to better match real 
world conditions. As with any engineering analysis of this type, variation from the estimated 
flood heights and floodplain boundaries is possible. Details of FEMA's requirements for the 
FISs and flood mapping process that produces these data are available in the Guidelines and 
Specifications for Flood Hazard Mapping Partners. Horizontal accuracy was tested by manual 
comparison of source graphics with hardcopy plots and a symbolized display on an interactive 
computer graphic system. 

Independent quality control testing of FEMAs DFIRM database was also performed. 

Vertical_Positional_Accuracy: 
Vertical_Positional_Accuracy_Report: The DFIRM Database consists of countywide vector files 
and associated attributes produced in conjunction with the hard copy FEMA FIRMs. The 
published effective FIRM and DFIRM maps are issued as the official designation of the 
SFHAs. As such they are adopted by local communities and form the basis for administration 
of the NFIP. For these purposes they are authoritative. Provisions exist in the regulations for 
public review, appeals and corrections of the flood risk information shown to better match real 
world conditions. As with any engineering analysis of this type, variation from the estimated 
flood heights and floodplain boundaries is possible. Details of FEMA's requirements for the 
FISs and flood mapping process that produces these data are available in the Guidelines and 
Specifications for Flood Hazard Mapping Partners. Vertical accuracy was tested by manual 
comparison of source graphics with hardcopy plots and a symbolized display on an interactive 
computer graphic system. 

Independent quality control testing of FEMAs DFIRM database was also performed. 
Lineage 
Source_Information: 
Source_Citation: 

Citation_Information: 
Originator: Federal Emergency Management Agency 
Publication_Date: 1987 
Title: Flood Insurance Study, FLOOD COUNTY USA (Unincorporated areas). 
Geospatial_Data_Presentation_Form: map 
Publication_Information: 

Publication_Place: Washington, DC
Publisher: Federal Emergency Management Agency

Other_Citation_Details: The hydrologic and hydraulic analyses for the FIS dated April 
17, 1987, were prepared by the U.S. Army Corps of Engineers (USACE), Springfield 
District, for the Federal Emergency Management Agency (FEMA), under Inter-
Agency Agreement No. EMW-84-E-1506. That work was completed in December 
1985. Denominator_of_Source_Scale: 2400-12000 


Source_Scale_Denominator: 12,000 
Type_of_Source_Media: paper 
Source_Time_Period_of_Content: 

Time_Period_Information: 
Single_Date/Time: 

Calendar_Date: 19870601 

Source_Currentness_Reference: Effective Date 

Source_Citation_Abbreviation: FIS1 

Source_Contribution: Spatial and attribute information, floodplain widths, BFEs, floodplain 
location. 
Source_Information: 
Source_Citation: 
Citation_Information: 
Originator: Federal Emergency Management Agency 

Publication_Date: 1987
Title: Flood Insurance Study, FLOODVILLE, Town of

Geospatial_Data_Presentation_Form: map 

Publication_Information: 
Publication_Place: Washington, DC 
Publisher: Federal Emergency Management Agency 

Other_Citation_Details: The hydrologic and hydraulic analyses for the FIS report dated 
April 17, 1987, were prepared by the USACE, Springfield District, for the FEMA, 
under Inter-Agency Agreement No. EMW-84-E-1506, Project Order No. 1, 
Amendment No. 4. That work was completed in December 1985. 
Denominator_of_Source_Scale: 2400-12000 

Source_Scale_Denominator: 12, 000 
Type_of_Source_Media: paper 
Source_Time_Period_of_Content: 

Time_Period_Information: 
Single_Date/Time: 

Calendar_Date: 19870601 

Source_Currentness_Reference: Effective Date 

Source_Citation_Abbreviation: FIS2 

Source_Contribution: Spatial and attribute information, floodplain widths, BFEs, floodplain 
location. 
Source_Information: 
Source_Citation: 

Citation_Information: 
Originator: Federal Emergency Management Agency 
Publication_Date: 1998 
Title: Flood Insurance Study Report, FLOOD COUNTY, USA and Incorporated areas. 
Geospatial_Data_Presentation_Form: map 
Publication_Information: 

Publication_Place: Washington, DC
Publisher: Federal Emergency Management Agency

Other_Citation_Details: For this countywide FIS, the hydrologic and hydraulic analyses 
were prepared by USACE for FEMA, under Inter-Agency Agreement No. EMW-94-
C-0019. This work was completed in October 1995. Denominator_of_Source_Scale: 
2400-12000 

Source_Scale_Denominator: 12000 
Type_of_Source_Media: paper 
Source_Time_Period_of_Content: 

Time_Period_Information: 
Single_Date/Time: 

Calendar_Date: 19980701 

Source_Currentness_Reference: Effective Date 


Source_Citation_Abbreviation: FIS3 

Source_Contribution: Spatial and attribute information, floodplain widths, BFEs, floodplain 
location. 
Source_Information: 
Source_Citation: 
Citation_Information: 
Originator: Town of Floodville Stormwater Management Department, 126 Royal Oaks 

Drive, Suite 201, Floodville, USA 99150 
Publication_Date: 1995 
Title: Base map for Floodville, USA 
Geospatial_Data_Presentation_Form: vector digital data 
Publication_Information: 

Publication_Place: Floodville, USA 
Publisher: Town of Floodville Stormwater Management 
Other_Citation_Details: These files were photogrammetrically compiled at scales of 

1"=200' (urban areas) and 1"=400' (rural areas) from aerial photographs. 
Source_Scale_Denominator: 4, 800 
Type_of_Source_Media: CD-ROM 
Source_Time_Period_of_Content: 

Time_Period_Information: 
Single_Date/Time: 
Calendar_Date: 19950301 

Source_Currentness_Reference: ground conditions 
Source_Citation_Abbreviation: BASE1 
Source_Contribution: Location of roads, railroads, bridges, streams and other physical features 

shown. 

Source_Information: 
Source_Citation: 
Citation_Information: 
Originator: Flood County Geographic Information Systems Department, 1110 South 

Road, Suite 205, Floodville, USA 99150 
Publication_Date: 1995 
Title: Base map for Flood County, USA 
Geospatial_Data_Presentation_Form: vector digital data 
Publication_Information: 

Publication_Place: Floodville, USA 
Publisher: Flood County Geographic Information Systems Department 
Other_Citation_Details: These files were photogrammetrically compiled at scales of 

1"=200' (urban areas) and 1"=400' (rural areas) from aerial photographs. 
Source_Scale_Denominator: 4,800 
Type_of_Source_Media: CD-ROM 
Source_Time_Period_of_Content: 

Time_Period_Information: 
Single_Date/Time: 
Calendar_Date: 19950301 

Source_Currentness_Reference: ground conditions 
Source_Citation_Abbreviation: BASE2 
Source_Contribution: Location of roads, railroads, bridges, streams and other physical features 

shown. 
Source_Information: 
Source_Citation: 

Citation_Information: 
Originator: U.S. Geological Survey 
Publication_Date: 1998 
Title: Digital Orthophoto Quadrangle 
Geospatial_Data_Presentation_Form: remote-sensing image 


Publication_Information: 

Publication_Place: Reston, VA 
Publisher: U.S. Geological Survey 
Other_Citation_Details: The digital orthophoto quadrangle (DOQ) is a 1-meter ground 

resolution, quarter-quadrangle (3.75-minutes of latitude by 3.75-minutes of longitude) 
image cast on the Universal Transverse Mercator Projection (UTM) on the North 
American Datum of 1983 (NAD83). The imagery is based on panchromatic black 
and white (or color infra-red) NAPP or NAPP-like photography. 

Source_Scale_Denominator: 12,000 
Type_of_Source_Media: CD-ROM 
Source_Time_Period_of_Content: 

Time_Period_Information: 
Single_Date/Time: 
Calendar_Date: 19970301 

Source_Currentness_Reference: ground conditions 
Source_Citation_Abbreviation: BASE3 
Source_Contribution: Location of roads, railroads, bridges, streams and other physical features 

shown. 

Process_Step: 

Process_Description: The DFIRM Database is compiled in conjunction with the hard copy 
FIRM and the Final printed FIS report. The specifics of the hydrologic and hydraulic analyses 
performed are detailed in the FIS report. The results of these studies are submitted in digital 
format to FEMA. These data and unrevised data from effective FIRMs are compiled onto the 
base map used for DFIRM publication and checked for accuracy and compliance with FEMA 
standards. 

Source_Used_Citation_Abbreviation: FIS1-FIS3, BASE1-BASE3 
Process_Date: 1996 
Spatial_Data_Organization_Information: 
Direct_Spatial_Reference_Method: Vector and raster 
Point_and_Vector_Object_Information: 
SDTS_Terms_Description: 
SDTS_Point_and_Vector_Object_Type: Point 
SDTS_Terms_Description: 
SDTS_Point_and_Vector_Object_Type: String 
SDTS_Terms_Description: 
SDTS_Point_and_Vector_Object_Type: GT -polygon composed of chains 
Raster_Object_Information: 
Raster_Object_Type: Pixel 
Spatial_Reference_Information: 
Horizontal_Coordinate_System_Definition: 
Planar: 
Grid_Coordinate_System: 

Grid_Coordinate_System_Name: Universal Transverse Mercator 

Universal_Transverse_Mercator: 
UTM_Zone_Number: 16 
Transverse_Mercator: 

Scale_Factor_at_Central_Meridian: 0.9996
Longitude_of_Central_Meridian: -87.0
Latitude_of_Projection_Origin: 0.0
False_Easting: 500000
False_Northing: 0.0

Planar_Coordinate_Information: 
Planar_Coordinate_Encoding_Method: Coordinate Pair 
Coordinate_Representation: 

Abscissa_Resolution: 0.061 
Ordinate_Resolution: 0.061 


Planar_Distance_Units: meters 
Geodetic_Model: 

Horizontal_Datum_Name: North American Datum 1983 
Ellipsoid_Name: Geodetic Reference System 80 
Semi-major_Axis: 6378206.4 
Denominator_of_Flattening_Ratio: 294.98 

Vertical_Coordinate_System_Definition: 
Altitude_System_Definition: 

Altitude_Datum_Name: National Geodetic Vertical Datum of 1929
Altitude_Resolution: 0.03
Altitude_Distance_Units: feet

Altitude_Encoding_Method: Attribute Values 
Entity_and_Attribute_Information: 
Overview_Description: 

Entity_and_Attribute_Overview: The DFIRM Database is made up of several data themes containing 
both spatial and attribute information. These data together represent the current flood risk for the 
subject area as identified by FEMA. The attribute tables include SFHA locations, flood zone 
designations, BFEs, political entities, cross-section locations, FIRM panel information, and other 
data related to the NFIP. 

Entity_and_Attribute_Detail_Citation: Appendix L of FEMAs Guidelines and Specifications for 
FEMA Flood Hazard Mapping Partners contains a detailed description of each attribute code and a 
reference to other relevant information. 

The following tables are included in this data set: 
S_BFE 
S_Fld_Haz_Ar 
S_Fld_Haz_Ln 
S_Gen_Struct 
S_LOMR 
L_Stn_Start 
S_Wtr_Ar 
S_Wtr_Ln 
S_XS 
L_Wtr_Nm 
S_Base_Index 
S_Perm_Bmk 
S_PLSS_AR 
S_PLSS_LN 
S_Pol_Ar 
S_Pol_Ln 
S_Quad_Index 
S_Label_Ld 
S_Trnsport_Ln 
S_Label_Pt 

Distribution_Information: 
Distributor: 
Contact_Information: 
Contact_Organization_Primary: 
Contact_Organization: Mapping Partner Contact 

Contact_Address: 
Address_Type: mailing address 
Address: Mapping Partner Address 
City: Mapping Partner City 
State_or_Province: Mapping Partner State 
Postal_Code: Mapping Partner Zip Code 
Country: Mapping Partner Country 


Contact_Voice_Telephone: Mapping Partner Phone Number 
Contact_Electronic_Mail_Address: Mapping Partner Email Address 
Contact_Instructions: Details for Mapping Partner distribution of data 

Distribution_Liability: Mapping Partner Liability Disclaimer 

Standard_Order_Process: 
Non-digital_Form: Information about hardcopy versions available 
Digital_Form: 

Digital_Transfer_Information: 
Format_Name: Mapping Partner Data Format 
Format_Version_Number: 1 

Digital_Transfer_Option: 

Offline_Option: 
Offline_Media: CD-ROM 
Recording_Format: ISO 9660 

Fees: Contact Distributor 

Metadata_Reference_Information: 
Metadata_Date: 19980509 
Metadata_Contact: 
Contact_Information: 
Contact_Organization_Primary: 
Contact_Organization: Mapping Partner Contact 
Contact_Position: Mapping Partner Position 
Contact_Address: 
Address_Type: mailing address 
Address: Mapping Partner Address 
City: Mapping Partner City 
State_or_Province: Mapping Partner State 
Postal_Code: Mapping Partner Zip Code 
Country: Mapping Partner Country 
Contact_Voice_Telephone: Mapping Partner Phone 
Contact_Electronic_Mail_Address: Mapping Partner Email Address 
Metadata_Standard_Name: FGDC Content Standards for Digital Geospatial Metadata 
Metadata_Standard_Version: FGDC-STD-001-1998 


L.7 Database Table Structure Requirements for Preliminary 
and Final Digital Flood Insurance Rate Map Databases 

Table: S_Base_Index 

This table is required if a raster base map was used as the base map for the Flood Insurance Rate 
Map (FIRM). 

The S_Base_Index table contains information about the raster data used as a base map for the 
study area. A spatial file with locational information also corresponds with this data table. 

The spatial elements representing raster base map tile index features are rectangular polygons. 
For standard U.S. Geological Survey Digital Ortho Quadrangles, polygons must match quarter-
quad boundaries (excluding overedge). Otherwise, polygons must match the boundaries of the 
raster tiles used (excluding overedge if present). 

This is a Standard DFIRM Database table. 

The S_Base_Index table contains the following elements. 

BASE_ID R S Primary key for table lookup. Assigned by table creator. 

FILENAME R S Base Filename. This filename must be assigned by the raster base 
map provider or the table creator. The filename should match the 
filename or specific product identifier assigned by the primary 
distributor of the raster base map used. This must be the complete 
filename including the file extension. This identifier must allow the 
user of the DFIRM database to unambiguously identify the raster 
base maps used on the FIRM to the primary distributor of the raster 
base map. 

BASE_DATE R S Base Date. This is the date that raster base map was acquired by 
the producer of the base map. For a vector base map that is 
rasterized for distribution, this data should be the acquisition date 
for the original vector base map. 

SOURCE_CIT R S Source Citation. Abbreviation used in the metadata file when 
describing the source information for the S_Base_Index table. 


Table: S_Base_Index

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
BASE_ID R S text 11 string 11 character 11 11 character 11 
FILENAME R S text 50 string 50 character 50 50 character 50 
BASE_DATE R S date/time 8 yyyymmdd 00/00/0000 date date 8 10 date 
SOURCE_CIT R S text 11 string 11 character 11 11 character 11 

L-271


Table: S_BFE 

The Base Flood Elevation (BFE) table is required for any digital data where BFE lines will be 
shown on the corresponding Flood Insurance Rate Map (FIRM). Normally if there are any 
riverine AE zones, BFE lines are required. 

The S_BFE table contains information about the BFEs within a study area. A spatial file with 
locational information also corresponds with this data table. BFE lines indicate the rounded 
whole-foot water surface elevation of the 1-percent-annual-chance flood. 

The spatial elements representing BFE features are lines extending from Special Flood Hazard 
Area (SFHA) boundary to SFHA boundary. The BFE lines will have no visible gaps or 
overshoots between the SFHA boundary and the end of the BFE line at the publication scale of 
the DFIRM. However, the ends of the BFE lines are not necessarily snapped precisely to the 
SFHA boundary. Each BFE is represented by a single line. While BFE lines are depicted as 
wavy lines on the hardcopy FIRM, they should be primarily straight lines in the spatial data, 
although they may bend consistent with procedures described in Volume 1 of these Guidelines. 

This is a Standard DFIRM Database table. 

The S_BFE table contains the following elements. 

BFE_LN_ID R S Primary key for table lookup. Assigned by table creator. 

ELEV R S BFE. The rounded, whole-foot elevation of the 1-percent-annual-
chance flood. This is the value of the BFE that is printed next to 
the BFE line on the FIRM. 

LEN_UNIT R S BFE Units. This unit indicates the measurement system used for 
the BFEs. Normally this would be feet. Acceptable values for this 
field are listed in the D_Length_Units table. 

V_DATUM R S Vertical Datum. The vertical datum indicates the reference surface 
from which the flood elevations are measured. Normally this 
would be North American Vertical Datum of 1988 for new studies. 
Acceptable values for this field are listed in the D_V_Datum table. 

SOURCE_CIT R S Source Citation. Abbreviation used in the metadata file when 
describing the source information for the S_BFE table. 


Table: S_BFE

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
BFE_LN_ID R S text 11 string 11 character 11 11 character 11 
ELEV R S 
number 
(double) 8 2 number 13 2 numeric 8 13 2 decimal 15 2 
LEN_UNIT R S text 20 string 20 character 20 20 character 20 
V_DATUM R S text 6 string 6 character 6 6 character 6 
SOURCE_CIT R S text 11 string 11 character 11 11 character 11 

L-273


Table: S_CBRS 

This table only applies to coastal areas that have specially protected areas designated by 
Congress on John H. Chafee Coastal Barrier Resources System (CBRS) maps. Authoritative 
CBRS boundary locations are shown on these maps administered by the U.S. Fish and Wildlife 
Service. Normally these areas are already shown on existing Federal Emergency Management 
Agency (FEMA) maps for the area. CBRS areas have restrictions on Federal funding (including 
flood insurance coverage) after specified dates for new or substantially improved structures. See 
Section 2.2 and Appendix K of these Guidelines for more detailed information about CBRS 
areas. 

The S_CBRS table contains information about the CBRS areas within the study area, if 
applicable. A spatial file with locational information also corresponds with this data table. 

The spatial elements representing CBRS features are closed polygons. Each contiguous CBRS 
area of the same CBRS_TYP and same CBRS_DATE must be a single polygon. 

This is a Standard DFIRM Database table. 

The S_CBRS table contains the following elements. 

CBRS_ID R S Primary key for table lookup. Assigned by table creator. 

CBRS_TYP A S CBRS Type. The type code provides details of the types of 
prohibitions that apply to the area. Normally this would be a CBRS 
area or Otherwise Protected Area (OPA). Acceptable values for 
this field are listed in the D_CBRS_Type table. This field is 
applicable if CBRS_TF is true. Otherwise this field is null. 

CBRS_DATE A S CBRS Date. Legislative or administrative date on which 
prohibitions for the CBRS area apply. This must be indicated on 
the Flood Insurance Rate Map with a note or with a fill pattern 
indicated on the legend. This field is applicable if CBRS_TF is 
true. Otherwise this field is null. 

CBRS_TF R S This field is True if the area is a CBRS or an OPA. Enter T for 
true or F for false. 

SOURCE_CIT R S Source Citation. Abbreviation used in the metadata file when 
describing the source information for the S_CBRS table. 


Table: S_CBRS

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
CBRS_ID R S text 11 string 11 character 11 11 character 11 
CBRS_TYP A S text 35 string 35 character 35 35 character 35 
CBRS_DATE A S date/time 8 yyyymmdd 00/00/0000 date date 8 10 date 
CBRS_TF R S text 1 string 1 character 1 1 character 1 
SOURCE_CIT R S text 11 string 11 character 11 11 character 11 

L-275


Table: S_Cst_Gage 

This table is required when gage information is used to support the calibration of models or 
methods used in the analysis of coastal flood hazards and may be used in the determination of 
flood heights. 

The S_Cst_Gage table contains information about coastal gages for the study area. The spatial 
location of these gages may be some distance from the areas for which coastal flood hazards 
were determined. A spatial file with locational information also corresponds with this data 
table. 

The spatial elements representing the coastal gages are points. 

This is an Enhanced DFIRM Database table.
The S_Cst_Gage table contains the following elements.
GAGE_ID R E Primary key for table lookup. Assigned by table creator.

CST_MDL_ID A E Coastal Model Identification. This field is populated by a linking 
element to the L_Cst_Model table. The L_Cst_Model table 
contains detailed information about the coastal models that were 
used to determine the coastal flood hazard for the area of each 
individual gage. This ID field should contain a number that 
matches the CST_MDL_ID field for a record in the L_Cst_Model. 
Multiple gages may link to a single record in the L_Cst_Model 
table. 

GAGE_NM R E Gage name assigned by agency maintaining gage. 

AGENCY R E Name of agency maintaining gage. 

REC_INTVL A E Recording Interval. This field is populated only if the coastal gage 
is a fixed-interval gage. 

TIME_UNIT A E Recording Interval Time Unit. This field is populated only if the 
coastal gage is a fixed-interval gage. 

START_PD R E Gage Record Starting Date. Start of earliest period of record used 
in gage analysis. 

END_PD R E Gage Record Ending Date. End of latest period of record used in 
gage analysis. 

GAGE_TYPE R E Gage Type. This value indicates the type of coastal gage. 


WVDIR_TF R E Does the gage record wave direction True or False? Enter "T" for 
true or "F" for false. 

WDSPD_TF R E Does the gage record wind speed True or False? Enter "T" for true 
or "F" for false. 

WDDIR_TF R E Does the gage record wind direction True or False? Enter "T" for 
true or "F" for false. 

SOURCE_CIT R E Source Citation. Abbreviation used in the metadata file when 
describing the source information for the S_Cst_Gage table. 


Table: S_Cst_Gage

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
GAGE_ID R E text 11 string 11 character 11 11 character 11 
CST_MDL_ID A E text 11 string 11 character 11 11 character 11 
GAGE_NM R E text 150 string 150 character 150 150 character 150 
AGENCY R E text 150 string 150 character 150 150 character 150 
REC_INTVL A E text 11 string 11 character 11 11 character 11 
TIME_UNIT A E text 20 string 11 character 11 11 character 11 
START_PD R E date/time 8 yyyymmdd 00/00/0000 date date 8 10 date 
END_PD R E date/time 8 yyyymmdd 00/00/0000 date date 8 10 date 
GAGE_TYPE R E text 40 string 40 character 40 40 character 40 
WVDIR_TF R E text 1 string 1 character 1 1 character 1 
WDSPD_TF R E text 1 string 1 character 1 1 character 1 
WDDIR_TF R E text 1 string 1 character 1 1 character 1 
SOURCE_CIT R E text 11 string 11 character 11 11 character 11 

L-278


Table: S_Cst_Tsct_Ln 

This table is required when the corresponding Flood Insurance Rate Map (FIRM) and/or Flood 
Insurance Study (FIS) will show coastal transect locations. Normally this is any area with a 
coastal study. 

The S_Cst_Tsct_Ln table contains information about the Coastal Transect Lines within the study area, if 
applicable. The transect lines indicate the location that was used to provide representative topographic 
information for the coastal flood models used. A spatial file with locational information also corresponds 
with this data table. 

The spatial elements representing coastal transects are lines generally extending from offshore all 
the way across the coastal floodplain. Transects can also extend seaward when wave runup 
modeling is used into determining coastal flood hazards. Each transect should be represented by 
a single line feature without the circles on each end shown on the hard copy map. The location 
and shape of the lines should depict as accurately as possible the position of the transect used. 

This is a modified Standard DFIRM Database table that includes Standard DFIRM Database 
items and Enhanced Database items. All items after SOURCE_CIT are Enhanced. 

The S_Cst_Tsct_Ln table contains the following elements. 

TRAN_LN_ID R S Primary key for table lookup. Assigned by table creator. 

TRAN_NO R S Transect Number. Transect number as shown on FIRM or in FIS. 
Each transect is normally numbered sequentially. 

SOURCE_CIT R S Source Citation. Abbreviation used in the metadata file when 
describing the source information for the S_Cst_Tsct_Ln table. 

CST_MDL_ID A E Coastal Model Identification. This field is populated by a linking 
element to the L_Cst_Model table. The L_Cst_Model table 
contains detailed information about the coastal models that were 
used to determine the coastal flood hazard for the area of each 
individual transect line. This ID field should contain a number that 
matches the CST_MDL_ID field for a record in the L_Cst_Model. 
Multiple transects may link to a single record in the L_Cst_Model 
table. This field is not required for digital conversion of existing 
FISs. Significant additional research may be required to identify 
the model that applies for each transect. However, for new coastal 
studies, this field is required. 

SETUP_DPTH A E Wave Set-up Depth. This is the depth of wave setup that is added 
to the 1% annual chance stillwater elevation. 

SIG_HT A E Significant Wave Height. This is the wave height associated with 
the 1% annual chance storm event. It is the average height of the 


highest 1/3 of all waves. It is used in WHAFIS 3.0 and RUNUP 2.0 
models. 

SIG_PD A E Significant Wave Period. This is the wave period associated with 
the 1% annual chance storm event. It is the time it takes for a wave 
of the significant wave height to pass a point. 

CON_HT A E Controlling Wave Height. 1.6 times the significant wave height. 

CON_PD A E Controlling Wave Period. The time it takes for a wave of the 
controlling wave height to pass a point. 

MEAN_HT A E Mean Wave Height. Average height of all waves. This information 
is typically derived from wave gage data. 

MEAN_PD R E Mean Wave Period. Average period of all waves. This information 
is typically derived from wave gage data. 

EROS_METH A E Erosion Methodology. Describes the erosion methodology. 

TIME_UNIT R E Units of Time Measurement. This field is populated if there is a 
value entered for the significant wave period, controlling wave 
period, or the mean wave period. The period values all should use 
the same unit of time measurement. Acceptable values for this field 
are listed in the D_Time_Units table. 

V_DATUM R E Vertical Datum. This is the vertical datum of the printed FIRM. 
The vertical datum describes the reference surface from which 
elevation on the map is measured. Normally this would be North 
American Vertical Datum of 1988 for new studies. Acceptable 
values for this field are listed in the D_V_Datum table. 

LEN_UNIT R E Length Units. This unit indicates the measurement system used for 
height. Normally this would be feet. Acceptable values for this 
field are listed in the D_Length_Units table. 

VZONE_EXT R E V Zone Extent. This information provides a brief summary to users 
about the predominating methodology that was used to determine 
the landward extent of the V Zone in any mapped flood hazard area. 
Acceptable values for this field are listed in the D_VZone table. 

METHOD R E Source Method. This value describes the general methodology used 
in deriving the station and elevation point data along transects used 
in coastal flood hazards. Acceptable values for this field are listed 
in the D_Method table. 

EFF_TF R E Is the coastal transect part of the effective study True or False? 
Enter "T" for true or "F" for false. 


SHOWN_FIRM R E Transect Shown on FIRM. Is the transect shown on the FIRM True 
or False? Enter "T" for true or "F" for false. 

SHR_ROUGH R E Shoreline Roughness. This value is the shoreline type classification 
that relates each transect with a shoreline type. This information 
can be used in conjunction with other coastal hazard analyses or 
applications and provides a useful set of data about relative 
shoreline roughness. Acceptable values for this field are listed in 
the D_Shr_Rough table. 

L_RANGE R E Left Range of Coastal Transect. Looking landward, the range is the 
along-shore distance to the left of the transect line that the transect 
is intended to represent. 

L_DIRECT R E Direction of Left Range. Direction is entered as the bearing of the 
range away from the transect. The left range direction is measured 
in degrees and is the angle of an arc taken in a clockwise direction 
from north to the ranges bearing. If the transect is oriented 
perpendicular to the shoreline, this value will be +/-90 degrees of 
the transect's direction in degrees from north. 

R_RANGE R E Right Range of Coastal Transect. Looking landward, the range is 
the along-shore distance to the right of the transect line that the 
transect is intended to represent 

R_DIRECT R E Direction of Right Range. Direction is entered as the bearing of the 
range away from the transect. The right range direction is measured 
in degrees and is the angle of an arc taken in a clockwise direction 
from north to the ranges bearing. If the transect is oriented 
perpendicular to the shoreline, this value will be +/-90 degrees of 
the transect's in direction in degrees from north. 

LOC_DESC R E Location Description. This is a description of the location of the 
coastal transects. This description is used and/or can be found in 
the transect table in the FIS text. 

XCOORD R E X-Coordinate. The X-coordinate of the 0.0-foot elevation point 
along the transect. This point must fall on the transect and have the 
same horizontal datum of the study. The coordinates must be 
entered using the same coordinate system used for the DFIRM GIS 
data. If the S_Shore_Ln table is provided, the shoreline should cross 
the transect at this point. 


YCOORD R E Y-Coordinate. The Y-coordinate of the 0.0-foot elevation point 
along the transect. This point must fall on the transect and have the 
same horizontal datum of the study. The coordinates must be 
entered using the same coordinate system used for the DFIRM GIS 
data. If the S_Shore_Ln table is provided, the shoreline should 
cross the transect at this point. 

. 


Table: S_Cst_Tsct_Ln

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
Type 
field 
size dec format input mask type width Dec type 
item 
width 
output 
width dec type width dec 
TRAN_LN_ID R S Text 11 string 11 character 11 11 character 11 
TRAN_NO R S Text 4 string 4 character 4 4 character 4 
SOURCE_CIT R S Text 11 string 11 character 11 11 character 11 
CST_MDL_ID A E Text 11 string 11 character 11 11 character 11 
SETUP_DPTH A E 
number 
(double) 8 2 number 13 2 numeric 8 13 2 decimal 15 2 
SIG_HT A E 
number 
(double) 8 2 number 13 2 numeric 8 13 2 decimal 15 2 
SIG_PD A E 
number 
(double) 8 2 number 13 2 numeric 8 13 2 decimal 15 2 
CON_HT A E 
number 
(double) 8 2 number 13 2 numeric 8 13 2 decimal 15 2 
CON_PD A E 
number 
(double) 8 2 number 13 2 numeric 8 13 2 decimal 15 2 

L-283


MEAN_HT A E 
number 
(double) 8 2 number 13 2 numeric 8 13 2 decimal 15 2 
MEAN_PD R E 
number 
(double) 8 2 number 13 2 numeric 8 13 2 decimal 15 2 
EROS_METH A E Text 15 string 15 character 15 15 character 15 
TIME_UNIT R E Text 20 string 20 character 20 20 character 20 
V_DATUM R E Text 6 string 6 character 6 6 character 6 
LEN_UNIT R E Text 20 string 20 character 20 20 character 20 
VZONE_EXT R E Text 40 string 40 character 40 40 character 40 
METHOD R E Text 20 string 20 character 20 20 character 20 
EFF_TF R E Text 1 string 1 character 1 1 character 1 
SHOWN_FIRM R E Text 1 string 1 character 1 1 character 1 
SHR_ROUGH R E Text 10 string 10 character 10 10 character 10 
L_RANGE R E 
number 
(double) 8 2 number 13 2 numeric 8 13 2 decimal 15 2 
L_DIRECT R E 
number 
(double) 8 2 number 13 2 numeric 8 13 2 decimal 15 2 
R_RANGE R E number 8 2 number 13 2 numeric 8 13 2 decimal 15 2 

L-284


(double) 
R_DIRECT R E 
number 
(double) 8 2 number 13 2 numeric 8 13 2 decimal 15 2 
LOC_DESC R E Text 254 string 254 character 254 254 character 254 
XCOORD R E 
number 
(double) 8 2 string 13 2 numeric 8 13 2 decimal 15 2 
YCOORD R E 
number 
(double) 8 2 string 13 2 numeric 8 13 2 decimal 15 2 

L-285


Table: S_FIRM_Pan 

This table is required for all preliminary or final DFIRM databases. 

The S_FIRM_Pan table contains information about the Flood Insurance Rate Map (FIRM) panel 
area. A spatial file with locational information also corresponds with this data table. 

The spatial entities representing FIRM panels are polygons. The polygon for the FIRM panel 
corresponds to the panel neatlines. As a result, the panels are generally rectangular. In situations 
where a portion of a panel lies outside of the jurisdiction being mapped, the user must refer to the 
S_POL_AR table to determine the portion of the panel area where the DFIRM database shows 
the effective flood hazard data for the mapped jurisdiction. 

This is a Standard DFIRM Database table. 

The S_FIRM_Pan table contains the following elements. 

FIRM_ID R S Primary key for table lookup. Assigned by table creator. 

ST_FIPS R S State FIPS. This is the two-digit code that corresponds to the state 
Federal Information Processing Standard (FIPS) code. This is a 
standard numbering system that is used by the Federal government. 
Defined in FIPS Pub 6-4. These two numbers correspond to the 
first two digits of the panel number. 

PCOMM R S Community or County Identification Number. This is the 3rd 
through the 6th digits of the panel number. For community based 
maps this corresponds to the Federal Emergenc y Management 
Agency (FEMA) Community Identification number. For 
countywide maps this is the county (or county equivalent) FIPS 
code with a C. 

PANEL R S Panel Number. This is 7th through the 10th digits in the complete 
panel number. This is assigned by the scale of the map and the 
position within the community or county. The panel number 
scheme is described in detail in Appendix K of these Guidelines. 

SUFFIX R S Map Suffix. This is the final digit in the complete panel number. 
This is a letter suffix at the end of the panel number. 

FIRM_PAN R S FIRM Panel Number. This is the complete FIRM panel number, 
which is made up of ST_FIPS, PCOMM, PANEL, and SUFFIX. 
This is the 11-digit FIRM panel number that is shown in the title 
block of the map. 

PANEL_TYP R S Panel Type. The type of FIRM panel that identifies whether the 
panel is printed or not printed and whether it is community based or 


countywide mapping. Acceptable values for this field are listed in 
the D_Panel_Typ table. 

EFF_DATE A S Effective Date. This is the effective date of the current map 
revision. This field is not populated until the FIRM effective date is 
established and the Final FIRM is ready for hardcopy production by 
FEMA. Then it is required. 

SCALE R S Map Scale. This is the denominator of the FIRM scale as a ratio. 
For example, 24000 is the denominator for a 1 = 2000 map. 
Acceptable values for this field are listed in the D_Scale table. 

PNP_REASON A S Panel Not Printed Reason. This is the explanation of the reason for 
the FIRM panels that are not printed. See Appendix K of these 
Guidelines for a listing of Panel Not Printed reasons that may be 
used. Only completed if the hardcopy panel is not printed by 
FEMA. 

NW_LAT R S Northwest Latitude. This is the latitude of the northwest corner of 
the FIRM panel neatline. This value is in degrees, minutes, seconds 
(DDD MM SS.SSS). Normally this corresponds to U.S. Geological 
Survey (USGS) 7.5 quadrangle maps using North American 
Datum of 1983 (NAD83), or even subdivisions thereof. However 
this value must reflect the actual latitude if non-standard panel sizes 
are used. 

NW_LONG R S Northwest Longitude. This is the longitude of the northwest corner 
of the FIRM panel. This value is in degrees, minutes, seconds 
(DDD MM SS.SSS). Normally this corresponds to USGS 7.5 
quadrangle maps using NAD83, or even subdivisions thereof. 
However this value must reflect the actual longitude if non-standard 
panel sizes are used. 

SE_LAT R S Southeast Latitude. This is the latitude of the southeast corner of 
the FIRM panel. This value is in degrees, minutes, seconds (DDD 
MM SS.SSS). Normally this corresponds to USGS 7.5 quadrangle 
maps using NAD83, or even subdivisions thereof. However this 
value must reflect the actual latitude if non-standard panel sizes are 
used. 

SE_LONG R S Southeast Longitude. This is the longitude of the southeast corner 
of the FIRM panel. This value is in degrees, minutes, seconds 
(DDD MM SS.SSS). Normally this corresponds to USGS 7.5 
quadrangle maps using NAD83, or eve n subdivisions thereof. 
However this value must reflect the actual longitude if non-standard 
panel sizes are used. 


SOURCE_CIT R S Source Citation. Abbreviation used in the metadata file when 
describing the source information for the S_FIRM_Pan table. 


Table: S_FIRM_Pan

Field R/A R/A MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
FIRM_ID R S text 11 string 11 character 11 11 character 11 
ST_FIPS R S text 2 string 2 character 2 2 character 2 
PCOMM R S text 4 string 4 character 4 4 character 4 
PANEL R S text 4 string 4 character 4 4 character 4 
SUFFIX R S text 1 string 1 character 1 1 character 1 
FIRM_PAN R S text 11 string 11 character 11 11 character 11 
PANEL_TYP R S text 35 string 35 character 35 35 character 35 
EFF_DATE A S date/time 8 yyyymmdd 00/00/0000 date date 8 10 date 
SCALE R S text 5 string 5 character 5 5 character 5 
PNP_REASON A S text 50 string 50 character 50 50 character 50 
NW_LAT R S text 15 string 15 character 15 15 character 15 
NW_LONG R S text 15 string 15 character 15 15 character 15 
SE_LAT R S text 15 string 15 character 15 15 character 15 
SE_LONG R S text 15 string 15 character 15 15 character 15 

L-289


SOURCE_CIT R S text 11 string 11 character 11 11 character 11 

L-290


Table: S_Fld_Haz_Ar 

This table is required for all draft Digital Flood Insurance Rate Map data. 

The S_Fld_Haz_Ar table contains information about the flood hazards within the study area. A 
spatial file with locational information also corresponds with this data table. These zones are 
used by the federal Emergency Management Agency (FEMA) to designate the Special Flood 
Hazard Area (SFHA) and for insurance rating purposes. These data are the flood hazard areas 
that are or will be depicted on the Flood Insurance Rate Map (FIRM). A spatial file with 
locational information also corresponds with this data table. 

The spatial elements representing the flood zones are polygons. The entire area of the 
jurisdiction(s) mapped by the FIRM should have a corresponding flood zone polygon. There is 
one polygon for each contiguous flood zone designated. 

This is a modified Standard DFIRM Database table that includes Standard DFIRM Database 
items and Enhanced Database items. All items after SOURCE_CIT are Enhanced. 

The S_Fld_Haz_Ar table contains the following elements. 

FLD_AR_ID R S Primary key for table lookup. Assigned by table creator. 

FLD_ZONE R S Flood Zone. This is a flood zone designation. These zones are used 
by FEMA to designate the SFHAs and for insurance rating 
purposes. NOTE: The symbol % is a reserved symbol in most 
software packages so the word percent was abbreviated to PCT. 
Acceptable values for this field are listed in the D_Zone table. 

FLOODWAY A S Floodway Type. Floodway areas are designated by FEMA and 
adopted by communities to provide an area that will remain free of 
development to moderate increases in flood heights due to 
encroachment on the floodplain. Normal floodway areas are 
floodway. Special cases will have a note on the hardcopy FIRM. 
If the corresponding area is not designated as a floodway, this field 
is null. Acceptable values for this field are listed in the 
D_Floodway table. 

SFHA_TF R S Special Flood Hazard Area. If the area is within SFHA this field 
would be True. This field will be true for any area that is coded for 
any A or V zone flood areas. It should be false for any X or D zone 
flood areas. Enter T for true or F for false. 

STATIC_BFE A S Static Base Flood Elevation. For areas of constant Base Flood 
Elevation (BFE), the BFE value is shown beneath the zone label 
rather than on a BFE line. In this situation the same BFE applies to 
the entire polygon. This is normally occurs in lakes or coastal 


zones. This field is only populated where a static BFE is shown on 
the FIRM. 

V_DATUM A S Vertical Datum. The vertical datum indicates the reference surface 
from which the flood elevations are measured. Normally this would 
be North American Vertical Datum of 1988 for new studies. This 
field is only populated if the STATIC_BFE field is populated. 
Acceptable values for this field are listed in the D_V_Datum table. 

DEPTH A S Depth Value for Zone AO Areas. This is shown beneath the zone 
label on the FIRM. This field is only populated if a depth is shown 
on the FIRM. 

LEN_UNIT A S Length Units. This unit indicates the measurement system used for 
the BFEs and/or depths. Normally this would be feet. This field is 
only populated if the STATIC_BFE or DEPTH field is populated. 
Acceptable values for this field are listed in the D_Length_Units 
table. 

VELOCITY A S Velocity Measurement. This is shown beneath the zone label on the 
FIRM for alluvial fan areas (certain Zone AO areas). This value 
represents the velocity of the flood flow in this area. This field is 
only populated when a velocity is shown on the FIRM. 

VEL_UNIT A S Unit of Measurement for the Velocity Attribute. This is shown in 
the legend where alluvial fans are present. This field is only 
populated if the VELOCITY field is populated. Acceptable values 
for this field are listed in the D_Velocity_Units table. 

AR_REVERT A S If the area is Zone AR, this field would hold the zone that the area 
would revert to if the AR zone were removed. This field is only 
populated if the corresponding area is Zone AR. Acceptable values 
for this field are listed in the D_Zone table. 

BFE_REVERT A S If Zone is Zone AR, this field would hold the static base flood 
elevation for the reverted zone. This field is populated when Zone 
equals AR and the reverted zone has a static BFE. 

DEP_REVERT A S If Zone is Zone AR, this field would hold that flood depth for the 
reverted zone. This field is populated when Zone equals AR and 
the reverted zone has a depth assigned. 

SOURCE_CIT R S Source Citation. Abbreviation used in the metadata file when 
describing the source information for the S_Fld_Haz_Ar table. 
Normally, the flood hazard area polygon will be divided to 
distinguish areas modified by the most recent revision from areas 
based on the effective FIRM prior to the most recent revision. 
Revisions and sources prior to the most recent revision will not be 


tracked for individual polygons in the flood hazard areas table in the 
standard database. 

HYDRO_ID A E Hydrologic Model Identification. A code that provides a link to the 
hydrologic model table, L_Hydro_Model. The L_Hydro_Model 
table provides information on the methods used to determine the 
flood hazard for areas of shallow flooding and ponding. This ID 
field must contain a number that matches the HYDRO_ID field for 
a record in the L_Hydro_Model table. This attribute is only 
required for flood hazard areas with AO and AH zone designations 
or ponding associated with AE zones. 

CST_MDL_ID A E Coastal Model Identification. This field is populated by a linking 
element to the L_Cst_Model table. The L_Cst_Model table 
contains detailed information about the coastal models that were 
used to determine the coastal flood hazard for this area. This ID 
field must contain a number that matches the CST_MDL_ID field 
for a record in the L_Cst_Model table that documents coastal model 
information. This attribute is only required in areas for which flood 
hazard determinations do not consider wave hazards. The static 
BFE values in these areas are based on surge modeling and/or tidal 
analyses. When wave hazards are considered modeling information 
is linked to the transects used to complete the wave analysis. 


Table: S_Fld_Haz_Ar

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
FLD_AR_ID R S text 11 string 11 character 11 11 character 11 
FLD_ZONE R S text 55 string 55 character 55 55 character 55 
FLOODWAY A S text 30 string 30 character 30 30 character 30 
SFHA_TF R S text 1 string 1 character 1 1 character 1 
STATIC_BFE A S 
number 
(double) 8 2 number 13 2 numeric 8 13 2 decimal 15 2 
V_DATUM A S text 6 string 6 character 6 6 character 6 
DEPTH A S 
number 
(double) 8 2 number 13 2 numeric 8 13 2 decimal 15 2 
LEN_UNIT A S text 20 string 20 character 20 20 character 20 
VELOCITY A S 
number 
(double) 8 2 number 13 2 numeric 8 13 2 decimal 15 2 
VEL_UNIT A S text 20 string 20 character 20 20 character 20 
AR_REVERT A S text 6 string 6 character 6 6 character 6 

L-294


BFE_REVERT A S 
number 
(double) 
8 2 number 13 2 numeric 8 13 2 decimal 15 2 
DEP_REVERT A S 
number 
(double) 
8 2 number 13 2 numeric 8 13 2 decimal 15 2 
SOURCE_CIT R S text 11 string 11 character 11 11 character 11 
HYDRO_ID A E text 11 string 11 character 11 11 character 11 
CST_MDL_ID A E text 11 string 11 character 11 11 character 11 

L-295


Table: S_Fld_Haz_Ln 

This table is required for all preliminary or final DFIRM databases. 

The S_Fld_Haz_Ln table contains information about the flood hazard line features for the study 
area. A spatial file with locational information also corresponds with this data table. 

The spatial elements representing the boundaries of the flood hazard areas depicted on the Flood 
Insurance Rate Map (FIRM) are lines. 

This is a Standard DFIRM Database table. 

The S_Fld_Haz_Ln table contains the following elements. 

FLD_LN_ID R S Primary key for table lookup. Assigned by table creator. 

LN_TYP R S Line Type. These line types describe the flood boundary and may 
be used to indicate how the feature must be depicted on the 
hardcopy FIRM. Acceptable values for this field are listed in the 
D_Ln_Typ table. 


Table: S_Fld_Haz_Ln

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
FLD_LN_ID R S text 11 string 11 character 11 11 character 11 
LN_TYP R S text 45 string 45 character 45 45 character 45 

L-297


Table: S_Gen_Struct 

This table is required whenever hydraulic structures are shown in the flood profile. It is also 
required if levees are shown on the FIRM, channels containing the flooding are shown on the 
FIRM, or any other structure that impacts the areas flood risk is shown on the FIRM. 

The S_Gen_Struct table contains information about the hydraulic structures within the study 
area. It must include all structures shown in the flood profiles. In addition, levees, sea walls, 
channels that contain flooding, and other significant flood control structures shown on the Flood 
Insurance Rate Map (FIRM) must be included. A spatial file with locational information also 
corresponds with this data table. 

Spatial elements representing general structures are represented by lines. The lines must 
represent the primary characteristic of the structure. For example, bridges must be represented 
by the transportation centerline carried by the bridge. Dams must be represented by a line 
corresponding to the top of the dam. Levees must be represented by a line corresponding to the 
top of levee. A line corresponding to the centerline of the main barrel must represent a culvert. 

This is a Standard DFIRM Database table. 

The S_Gen_Struct table contains the following elements. 

STRUCT_ID R S Primary key for table lookup. Assigned by table creator. 

STRUCT_TYP R S Structure Type. Hydraulic structures within the study area. 
Acceptable values for this field are listed in the D_Struct_Typ table. 

STRUCT_NM A S Structure Name. This is the name of the feature and the name that 
will be shown on the hardcopy FIRM. This record is left blank if 
the structure is not named on FIRM and/or the name is unknown. 

WTR_NM R S Surface Water Feature Name. This is the formal name of the 
surface water feature associated with the structure, as it will appear 
on the hardcopy FIRM. 

SOURCE_CIT R S Source Citation. Abbreviation used in the metadata file when 
describing the source information for the S_Gen_Struct table. 


Table: S_Gen_Struct

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
STRUCT_ID R S text 11 string 11 character 11 11 character 11 
STRUCT_TYP R S text 36 string 36 character 36 36 character 36 
STRUCT_NM A S text 50 string 50 character 50 50 character 50 
WTR_NM R S text 100 string 100 character 100 100 character 100 
SOURCE_CIT R S text 11 string 11 character 11 11 character 11 

L-299


Table: S_Label_Ld 

This table is required for Digital Flood Insurance Rate Map (DFIRM) data if any label leader 
lines are shown on the hardcopy FIRM. 

The S_Label_Ld table contains information about leader lines that would connect labels to 
feature locations on base maps. The purpose of this table, along with the S_Label_Pt table is so 
that the Digital Flood Insurance Rate Map (DFIRM) database can contain the names of roads and 
other physical features in or near the Special Flood Hazard Areas regardless of the type or 
structure of the base map used. A spatial file with locational information also corresponds with 
this data table. 

The spatial entities representing label leaders will be lines. 

This is a Standard DFIRM Database table. 

The S_Label_Ld table contains the following elements. 

LEADER_ID R S Primary key for table lookup. Assigned by table creator. 

LABEL_TYPE R S Label type. This is a description of the planimetric features to 
which the labels and leaders are associated. For vector based maps, 
the labels and leaders will be associated with vector features in 
S_Trnsport_Ln, S_Wtr_Ar and S_Wtr_Ln. For maps with an 
ortho-photo base, the labels and leaders will be associated with 
DOQ water and transportation features. For maps that use both 
vector features and ortho-photos, all values may apply. Acceptable 
values for this field are listed in the D_Label_Typ table. 


Table: S_Label_Ld

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
LEADER_ID R S text 11 string 11 character 11 11 character 11 
LABEL_TYPE R S text 20 string 20 character 20 20 character 20 

L-301


Table: S_Label_Pt 

This table is required for all preliminary or final DFIRM databases. 

The S_Label_Pt table contains information for point locations that would link labels to base map 
features. The purpose of this table, along with the S_Label_Ld table is so that the Digital Flood 
Insurance Rate Map (DFIRM) database can contain the names of roads and other physical 
features in or near the Special Flood Hazard Areas (SFHAs) regardless of the type or structure of 
the base map used. A spatial file with locational information also corresponds with this data 
table. 

The spatial entities representing labels are points. The point corresponds to the lower left corner 
of the label. 

This is a Standard DFIRM Database table. 

The S_Label_Pt table contains the following elements. 

LABEL_ID R S Primary key for table lookup. Assigned by table creator. 

LABEL R S Label for map feature. 

LABEL_TYPE R S Label type. This is a description of the planimetric features to 
which the labels and leaders are associated. For vector based maps, 
the labels and leaders will be associated with vector features in 
S_Trnsport_Ln, S_Wtr_Ar and S_Wtr_Ln. For maps with an 
ortho-photo base, the labels and leaders will be associated with 
DOQ water and transportation features. For maps that use both 
vector features and ortho-photos, all values may apply. Acceptable 
values for this field are listed in the D_Label_Typ table. 

DEGREES R S The degrees of rotation required for the placement of a feature label 
onto a Flood Insurance Rate Map panel. The rotation angle of the 
text measured in degrees. The angle is zero for unrotated horizontal 
text and increases in a counterclockwise direction to 359. Text 
rotated clockwise has a negative value between 0 and 359. 


Table: S_Label_Pt

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
LABEL_ID R S text 11 string 11 character 11 11 character 11 
LABEL R S text 254 string 254 character 254 254 character 254 
LABEL_TYPE R S text 20 string 20 character 20 20 character 20 
DEGREES R S integer 2 0 number 4 0 binary 4 10 0 decimal 4 0 

L-303


Table: S_LOMR 

This table is required when a Mapping Partner incorporates the results of effective Letters of 
Map Revision (LOMRs) into the draft Digital Flood Insurance Rate Map (DFIRM) data 
submitted to the Federal Emergency Management Agency (FEMA). 

The S_LOMR table contains information about LOMR areas that are incorporated into the Flood 
Insurance Rate Map (FIRM). This table is planned as a mechanism for DFIRM producers to 
communicate areas of the DFIRM data that were updated to reflect the results of LOMRs. It is included 
in the draft DFIRM data submittal. It is not planned for distribution by FEMA once a complete map 
revision has incorporated these LOMRs into the effective FIRM panel. Therefore it is not included in the 
Preliminary or Final DFIRM data. A spatial file with locational information also corresponds with this 
data table. 

The spatial entities representing LOMRs are polygons. The spatial information contains the 
bounding polygon for each LOMR area. 

This is a modified Standard DFIRM Database table that includes Standard DFIRM Database 
items and Enhanced Database items. All items after SOURCE_CIT are Enhanced. 

The S_LOMR table contains the following elements. 

LOMR_ID R S Primary key for table lookup. Assigned by table creator. 

EFF_DATE R S Effective Date. Effective date of the LOMR. 

CASE_NO R S Case Number. This is the case number of the LOMR that is 
assigned by FEMA. The case number is used to track the LOMRs 
supporting documentation. 

SCALE R S Map Scale. This is the denominator of the effective LOMR scale as 
a ratio. For example, 24000 is the denominator for a 1 = 2000 
map. Acceptable values for this field are listed in the D_Scale 
table. 

SOURCE_CIT R S Source Citation. Abbreviation used in the metadata file when 
describing the source information for the S_LOMR table. 

STATUS R E Status of the LOMR. Valid entries for this field include the 
following: 

effective 

incorporated 

superseded 


Table: S_LOMR

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
LOMR_ID R S text 11 string 11 character 11 11 character 11 
EFF_DATE R S date/time 8 yyyymmdd 00/00/0000 date date 8 10 date 
CASE_NO R S text 13 string 13 character 13 13 character 13 
SCALE R S text 5 string 5 character 5 5 character 5 
SOURCE_CIT R S text 11 string 11 character 11 11 character 11 
STATUS R E text 12 string 12 character 12 12 character 12 

L-305


Table: S_Nodes 

This table is required for all studies with new or revised hydrologic data. A spatial file with 
locational information also corresponds with this data table. 

The S_Nodes table contains data only on the location of points used to define the topology of the 
hydrologic network. Nodes can be subbasin pourpoints, confluences, diversions, hydraulic 
structures, etc. Nodes are connected to each other via links, which are defined in S_Profil_Basln 
(see below). 

The spatial elements representing the nodes are points. 
This is an Enhanced DFIRM Database table. 

The S_Nodes table contains the following elements. 

NODE_ID R E Primary key for this table. Assigned by table creator. 

SOURCE_CIT R E Source Citation. Abbreviation used in the metadata file when 
describing the source information for S_Nodes. 


Table: S_Nodes

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
NODE_ID R E text 11 string 11 character 11 11 character 11 
SOURCE_CIT R E text 11 string 11 character 11 11 character 11 

L-307


Table: S_Ovrbnkln 

This table is required for a detailed study that uses overbank flow lengths as input data. 

The S_Ovrbnkln table contains information about overbank flow line features for the study area. 

The features are those lines along which overbank flow distances between two cross sections are 
measured. Between any two adjacent cross sections, there must be two overbank flow lines: one 
for the right overbank line and one for the left overbank line. The two lines may be one 
continuous line or may be broken at the cross section. However, if the line is broken, the line 
must be continuous between the cross sections; the endpoints of an overbank line must lie on a 
cross section. A spatial file with locational information also corresponds with this data table. 

Since models will eventually overlap, these features should represent the lines associated with 
the model for the base flood from which the effective FIRM was derived. 

Locations are based on standard engineering practice and should match locations used in the 
analysis. 

The spatial elements representing the boundaries of the flood hazards depicted on the FIRM are 
lines. 

This is an Enhanced DFIRM Database table. 

The S_Ovrbnkln table contains the following elements. 

OVRBNK_ID R E Primary key for table lookup. Assigned by table creator. 

WTR_NM R E Surface Water Feature Name. This is the formal name of the 
surface water feature, as it will appear on the hardcopy FIRM. 

OBNK_SIDE R E Overbank Side. Indicates which side the overbank line represents. 
Enter L for left or R for right. 

SOURCE_CIT R E Source Citation. Abbreviation used in the metadata file when 
describing the source information for the S_Ovrbnkln. 


Table: S_Ovrbnkln

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
OVRBNK_ID R E text 11 string 11 character 11 11 character 11 
WTR_NM R E text 100 string 100 character 100 100 character 100 
OBNK_SIDE R E text 1 string 1 character 1 1 character 1 
SOURCE_CIT R E text 11 string 11 character 11 11 character 11 

L-309


Table: S_Perm_Bmk 

This table is required unless there are no National Geodetic Survey (NGS) or other bench marks 
that meet the minimum standard in the jurisdiction covered by the Flood Insurance Rate Map 
(FIRM). 

The S_Perm_Bmk table contains information about Permanent Bench Marks that are associated 
with the study area. The bench marks shown in this file must meet the requirements specified in 
Subsection 1.4.1.4.1. A spatial file with locational information also corresponds with this data 
table. 

The spatial entities representing bench marks are points. Generally, the assigned Mapping must 
place these points based on the coordinates in the NGS database. However, the horizontal 
coordinates maintained by the NGS for vertical bench marks is often not very precise because 
the users usually rely on the location descriptions to locate the bench marks. If the source of the 
horizontal coordinates used by the NGS is not precise, the Mapping Partner may adjust the 
position based on better available data. 

This is a Standard DFIRM Database table. 

The S_Perm_Bmk table contains the following elements. 

BM_ID R S Primary key for table lookup. Assigned by table creator. 

PID R S Permanent Identifier. This must be the NGS assigned or 
community assigned permanent identifier. It must be unique for 
each bench mark. 

SOURCE_CIT R S Source Citation. Abbreviation used in the metadata file when 
describing the source information for the S_Perm_Bmk table. 


Table: S_Perm_Bmk

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
BM_ID R S text 11 string 11 character 11 11 character 11 
PID R S text 11 string 11 character 11 11 character 11 
SOURCE_CIT R S text 11 string 11 character 11 11 character 11 

L-311


Table: S_PFD_Ln 

This table is required when a primary frontal dune (PFD) is present along portions or all of the 
coastline within the modeled coastal floodplain. PFDs are not required to be continuous along 
the length of the studied shoreline. It is applicable when PFD_TF = T in the L_Cst_Model 
table. 

The S_PFD_Ln table contains information about the primary frontal dune features for the coastal 
study area. Primary frontal dunes are not shown on the FIRM but are used in the coastal 
floodplain analysis. They are lines that represent the back side of the first natural ridge inland 
from the coastal shoreline and where the gradient changes from steep to gentle. A spatial file 
with locational information also corresponds with this data table. 

The spatial elements representing the primary frontal dunes are lines. 

This is an Enhanced DFIRM Database table. 

The S_PFD_Ln table contains the following elements.
PFD_ID R E Primary key for table lookup. Assigned by table creator.

SOURCE_CIT R E Source Citation. Abbreviation used in the metadata file when 
describing the source information for the S_PFD_Ln table. 


Table: S_PFD_Ln

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
PFD_ID R E text 11 string 11 character 11 11 character 11 
SOURCE_CIT R E text 11 string 11 character 11 11 character 11 

L-313


Table: S_PLSS_Ar 

This table is required when U.S. Public Land Survey System (PLSS) areas are shown on the 
Flood Insurance Rate Map and the data used for the map can be distributed by FEMA at no cost. 

The S_PLSS_Ar table contains information about PLSS areas that are associated with the study 
area, if applicable. This would include the attributes for the range, township, and section areas. 
A spatial file with locational information also corresponds with this data table. 

The spatial elements representing the PLSS areas are polygons. Generally there is one polygon 
per section. The PLSS areas must cover the entire jurisdiction where sections are defined. 

In general, the Public Land Survey System table structure is fairly flexible depending on the 
format of the data available for the map. The Federal Emergency Management Agencys 
(FEMAs) objective is to have spatially accurate PLSS data to which the flood hazard 
information is referenced. Users must be able to identify section, township and range 
information on the printed maps. If these objectives are met, then almost any file structure is 
acceptable. PLSS features may be represented as either polygons or lines. With some data 
structures, it may not be practical to assign attributes to each spatial entity. While these 
attributes are desirable, FEMA recognizes that they may not always be easily available. This is 
acceptable because the PLSS system is a public system not maintained by FEMA. This 
information is provided for reference on the paper maps.. 

This is a Standard DFIRM Database table. 

The S_PLSS_Ar table contains the following elements. 

PLSS_AR_ID R S Primary key for table lookup. Assigned by table creator. 

RANGE A S Range Number. This is the range number assigned to the PLSS 
area shown. This attribute would also include the designation of E 
(east) or W (west) as part of the data. For example, 21W would be 
an acceptable value. This field is applicable whenever the 
SECT_NO does not equal zero. 

TWP A S Township. This is the township number assigned to the PLSS area 
shown. This attribute would also include the designation of N 
(north) or S (south) as part of the data. For example, 14S would be 
an acceptable value. This field is applicable whenever the 
SECT_NO does not equal zero. 

SECT_NO R S Section. This is the section number assigned to the PLSS area 
shown. 

SOURCE_CIT R S Source Citation. Abbreviation used in the metadata file when 
describing the source information for the S_PLSS_Ar table. This 


field is required when source citation information is not provided 
by the S_PLSS_Ln table. 


Table: S_PLSS_Ar

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
PLSS_AR_ID R S text 11 string 11 character 11 11 character 11 
RANGE A S text 8 string 8 character 8 8 character 8 
TWP A S text 8 string 8 character 8 8 character 8 
SECT_NO R S text 4 string 4 character 4 4 character 4 
SOURCE_CIT R R text 11 string 11 character 11 11 character 11 

L-316


Table: S_PLSS_Ln 

This table is required when U.S. Public Land Survey System (PLSS) areas are shown on the 
FIRM and the data used for the map can be distributed by FEMA at no cost. 

The S_PLSS_Ln table contains information about the boundary lines for the PLSS that is 
associated with the study area, if applicable. This would include the attributes for the adjacent 
range and township areas. 

In general, the Public Land Survey System table structure is fairly flexible depending on the 
format of the data available for the map. The Federal Emergency Management Agencys 
(FEMAs) objective is to have spatially accurate PLSS data to which the flood hazard 
information is referenced. Users must be able to identify section, township and range 
information on the printed maps. If these objectives are met, then almost any file structure is 
acceptable. PLSS features may be represented as either polygons or lines. With some data 
structures, it may not be practical to assign attributes to each spatial entity. While these 
attributes are desirable, FEMA recognizes that they may not always be easily available. This is 
acceptable because the PLSS system is a public system not maintained by FEMA. This 
information is provided for reference on the paper maps.. 

A spatial file with locational information corresponds with this data table. 

The spatial entities representing PLSS boundaries are lines. 

This is a Standard DFIRM Database table. 

The S_PLSS_Ln table contains the following elements. 

PLSS_LN_ID R S Primary key for table lookup. Assigned by table creator. 

LN_TYP R S Line Type. This describes the PLSS boundary and may be used to 
indicate how the feature must be depicted on the hardcopy Flood 
Insurance Rate Map (FIRM). Acceptable values for this field are 
listed in the D_Ln_Typ table. 

E_RANGE A S East Range Number. This is the range number assigned to the 
PLSS area shown to the east of the line feature. This number is 
shown on the hardcopy FIRM. This attribute would also include 
the designation of E (east) or W (west) as part of the data. For 
example, 21W would be an acceptable value. Only populated for 
lines that divide one range from another. 

W_RANGE A S West Range Number. This is the range number assigned to the 
PLSS area shown to the west of the line feature. This number is 
shown on the hardcopy FIRM. This attribute would also include 
the designation of E (east) or W (west) as part of the data. For 


example, 21W would be an acceptable value. Only populated for 
lines that divide one range from another. 

N_TWP A S North Township. This is the township number assigned to the 
PLSS area shown to the north of the line feature. This number is 
shown on the hardcopy FIRM. This attribute would also include 
the designation of N (north) or S (south) as part of the data. For 
example, 14S would be an acceptable value. Only populated for 
lines that divide one township from another. 

S_TWP A S South Township. This is the township number assigned to the 
PLSS area shown to the south of the line feature. This number is 
shown on the hardcopy FIRM. This attribute would also include 
the designation of N (north) or S (south) as part of the data. For 
example, 14S would be an acceptable value. Only populated for 
lines that divide one township from another. 

SOURCE_CIT R S Source Citation. Abbreviation used in the metadata file when 
describing the source information for the S_PLSS_Ln table. This 
field is required when source citation information is not provided 
by the S_PLSS_Ar table. 


Table: S_PLSS_Ln

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
PLSS_LN_ID R S text 11 string 11 character 11 11 character 11 
LN_TYP R S text 45 string 45 character 45 45 character 45 
E_RANGE A S text 8 string 8 character 8 8 character 8 
W_RANGE A S text 8 string 8 character 8 8 character 8 
N_TWP A S text 8 string 8 character 8 8 character 8 
S_TWP A S text 8 string 8 character 8 8 character 8 
SOURCE_CIT R S text 11 string 11 character 11 11 character 11 

L-319


Table: S_Pol_Ar 

This table is required for all preliminary or final DFIRM databases. 

The S_Pol_Ar table contains information about the Political Areas within the study area. This 
includes the attributes for the political areas and other areas such as forests, parks, military lands, 
and Tribal lands. For the National Flood Insurance Program (NFIP), it is important to know the 
jurisdiction that has land use authority over an area. Political jurisdictions individually agree to 
participate in the NFIP and availability of insurance, floodplain regulations, and insurance rates 
may vary by political jurisdiction. The political jurisdiction assigned to each area corresponds to 
the jurisdiction responsible for NFIP and floodplain management for that area. A spatial file 
with locational information also corresponds with this data table. 

The spatial entities representing political areas are polygons. 

This is a Standard DFIRM Database table. 

The S_Pol_Ar table contains the following elements. 

POL_AR_ID R S Primary key for table lookup. Assigned by table creator. 

POL_NAME1 R S Political Area Name 1. This is the primary name of the area shown. 
For areas that have more than one name, this would be the primary 
name with subsequent names shown in fields below. This would 
correspond to the official name of this jurisdiction used by the 
Federal Emergenc y Management Agency (FEMA) within the NFIP. 
For unincorporated areas of a county, this must be the county name 
(e.g., Montgomery County). 

POL_NAME2 A S Political Area Name 2. This is the secondary name of the area 
shown. Populated if there is a common name for an area other than 
the official jurisdiction name. 

CO_FIPS R S County Federal Information Processing Standard (FIPS) Code. 
This is the three-digit county FIPS code. This is a standard 
numbering system that is used by the Federal government. Defined 
in FIPS Pub 6-4. 

ST_FIPS R S State FIPS. This is the two-digit code that corresponds to the state 
FIPS code. This is a standard numbering system that is used by the 
Federal government. Defined in FIPS Pub 6-4. These two 
numbers correspond to the first two digits of the panel number. 

COMM_NO R S Community Number. This is the four-digit number assigned by 
FEMA to each community for tracking purposes under the NFIP. 
On newer Flood Insurance Rate Maps (FIRMs) the state FIPS and 
the community number appear below the community name where it 


is shown in the body of the map. For single jurisdiction FIRMs, 
this is the 3rd through the 6th digits of the panel number. This 
number can be obtained from the community status book that can 
be viewed at www.fema.gov/msc. Areas under Federal jurisdiction 
such as National Parks, National Forests, military bases, etc. do not 
have community numbers assigned by FEMA. These areas should 
have a value of FED in the COMM_NO field. Areas under state 
jurisdiction such as state parks and wildlife reservations should 
have a value of ST in the COMM_NO field. For any other 
jurisdictions where local community does not have the authority to 
administer the NFIP and FEMA does not assign a community 
number, the COMM_NO field should contain OTHR. 

CID R S Community Identification Number. This is the six-digit community 
number assigned by FEMA. It is created by combining the state 
FIPS code with the COMM_NO. If the jurisdiction does not have a 
community number assigned by FEMA, the CID is created by 
combining the state FIPS code with the abbreviation contained in 
the COMM_NO field (FED, ST, or OTHR). 

ANI_TF R S Area Not Included. This field contains information about the 
geographical area to determine if it is included in the FIRM or not. 
Areas Not Included fall within the extent of the FIRM, but no flood 
risk information is shown on this map. This is either because the 
area is mapped on another FEMA map or because the area is not 
mapped at all by FEMA. Enter T for true or F for false. 

COM_NFO_ID A S Community Information Identification. This attribute links to the 
table L_Comm_Info that contains information about the specific 
community. This table must contain a number that matches a 
corresponding number in the COM_NFO_ID field of the 
L_Comm_Info. This field is populated for any jurisdiction that has 
a CID number issued by FEMA. 


Table: S_Pol_Ar

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
POL_AR_ID R S text 11 string 11 character 11 11 character 11 
POL_NAME1 R S text 50 string 50 character 50 50 character 50 
POL_NAME2 A S text 50 string 50 character 50 50 character 50 
CO_FIPS R S text 3 string 3 character 3 3 character 3 
ST_FIPS R S text 2 string 2 character 2 2 character 2 
COMM_NO R S text 4 string 4 character 4 4 character 4 
CID R S text 6 string 6 character 6 6 character 6 
ANI_TF R S text 1 string 1 character 1 1 character 1 
COM_NFO_ID A S text 11 string 11 character 11 11 character 11 

L-322


Table: S_Pol_Ln 

This table is required for all preliminary or final DFIRM databases. 

The S_Pol_Ln table contains information about the boundaries of Political Areas within the 
study area. This would include the attributes for the political areas and other areas such as 
forests, parks, military lands, and Native American lands. A spatial file with locational 
information also corresponds with this data table. 

The spatial elements representing the boundaries of the political jurisdictions depicted on the 
Flood Insurance Rate Map (FIRM) are lines. 

This is a Standard DFIRM Database table. 

The S_Pol_Ln table contains the following elements. 

POL_LN_ID R S Primary key for table lookup. Assigned by table creator. 

LN_TYP R S Line Type. This describes the jurisdictional boundary and can be 
used to indicate how the feature must be depicted on the hardcopy 
FIRM. Acceptable values for this field are listed in the D_Ln_Typ 
table. 

SOURCE_CIT R S Source Citation. Abbreviation used in the metadata file when 
describing the source information for the S_Pol_Ln table. 


Table: S_Pol_Ln

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
POL_LN_ID R S text 11 string 11 character 11 11 character 11 
LN_TYP R S text 45 string 45 character 45 45 character 45 
SOURCE_CIT R S text 11 string 11 character 11 11 character 11 

L-324


Table: S_Precip_Gage 

This table is required when rain gages are used in developing the hydrologic analysis. A spatial 
file with locational information also corresponds with this data table. 

The spatial elements representing the precipitation gages are points. 

This is an Enhanced DFIRM Database table. 

The S_Precip_Gage table contains the following elements. 

PRECIP_ID R E Primary key for this table. Assigned by table creator. 

GAGE_ID R E Rain Gage Identification Number. The ID for the rain gage. 
Assigned by agency maintaining gage. 

AGENCY R E Agency. Name of agency maintaining gage. 

CASE_NO R E FEMA Case Number. The case number for the rain gage links to 
the L_Case_Info table. 

GAGE_TYPE R E Rain Gage Type. This attribute establishes gage type. Values 
include tipping, instantaneous, and fixed interval. Acceptable 
values for this field are listed in the D_Gage table. 

REC_INTVL A E Recording Interval. This field is populated only if the rain gage is a 
fixed-interval gage. 

TIME_UNIT A E Recording Interval Time Unit. This attribute establishes the unit of 
measure of the recording interval. This field is populated only if the 
rain gage is a fixed-interval gage. Acceptable values for this field 
are listed in the D_Time_Units table. 

START_PD R E Start Period. This value is the start of the earliest period of record 
used in the gage analysis. 

END_PD R E End Date. This value is the end of the latest period of record used 
in the gage analysis. 

SOURCE_CIT R E Source Citation. Abbreviation used in the metadata file when 
describing the source information for S_Precip_Gage. 


Table: S_Precip_Gage

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
PRECIP_ID R E text 11 string 11 character 11 11 character 11 
GAGE_ID R E text 25 string 25 character 25 25 character 25 
AGENCY R E text 150 string 150 character 150 150 character 150 
CASE_NO R E text 12 string 12 character 12 12 character 12 
GAGE_TYPE R E text 40 string 40 character 40 40 character 40 
REC_INTVL A E text 11 string 11 character 11 11 character 11 
TIME_UNIT A E text 20 string 20 character 20 20 character 20 
START_PD R E date/time 8 yyyymmdd 00/00/0000 date date 8 10 date 
END_PD R E date/time 8 yyyymmdd 00/00/0000 date date 8 10 date 
SOURCE_CIT R E text 11 string 11 character 11 11 character 11 

L-326


Table: S_Profil_Basln 

This table is required for a detailed study when hydrologic and hydraulic models have been 
developed for reaches of streams. The results of the models are shown on the FIRM. The profile 
baseline and/or stream centerline may or may not be shown on the FIRM. 

The S_Profil_Basln table contains information about profile baseline and stream centerline 
features for the study area. A spatial file with locational information also corresponds with this 
data table. The spatial elements representing the profile baseline and stream centerline are lines. 

This is an Enhanced DFIRM Database table. 

The S_Profil_Basln table contains the following elements. 

BASELN_ID R E Primary key for table lookup. Assigned by table creator. 

WTR_NM R E Surface Water Feature Name. This is the formal name of the 
surface water feature as it will appear on the hardcopy FIRM. 

WATER_TYP R E Surface Water Feature Type. The type value describes the kind of 
watercourse represented. Valid entries include items such as 
stream/river, channel, and shoreline/coastline. Acceptable values 
for this field are listed in the D_Water_Typ table. 

UP_NODE A E Upstream Node. This is the node ID at the upstream end of the 
reach. This ID field must contain a number that matches the 
NODE_ID field in the S_Nodes table, which documents points used 
to define the topology of the hydrologic network. This field is only 
populated when WATER_TYPs value equals PROFILE 
BASELINE or PROFILE BASELINE AND STREAM 
CENTERLINE. 

DN_NODE A E Downstream Node. This is the node ID at the downstream end of 
the reach. This ID field must contain a number that matches the 
NODE_ID field for a record in the S_Nodes table, which 
documents points used to define the topology of the hydrologic 
network. This field is only populated when WATER_TYPs value 
equals PROFILE BASELINE or PROFILE BASELINE AND 
STREAM CENTERLINE. 

ROUTE_METH A E Hydrologic Routing Method. This is the hydrologic routing method 
used for the reach. This field is only populated if hydrologic 
routing is used for the reach. 

SHOWN_FIRM R E Profile Baseline Shown on FIRM. This field is true only if the 
centerline is shown on the FIRM. Enter T for true or F  for 
false. 


SOURCE_CIT R E Source Citation. Abbreviation used in the metadata file when 
describing the source information for the S_Profil_Basln. 


Table: S_Profil_Basln

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
BASELN_ID R E text 11 string 11 character 11 11 character 11 
WTR_NM R E text 100 string 100 character 100 100 character 100 
WATER_TYP R E text 40 string 40 character 40 40 character 40 
UP_NODE A E text 11 string 11 character 11 11 character 11 
DN_NODE A E text 11 string 11 character 11 11 character 11 
ROUTE_METH A E text 254 string 254 character 254 254 character 254 
SHOWN_FIRM R E text 1 string 1 character 1 1 character 1 
SOURCE_CIT R E text 11 string 11 character 11 11 character 11 

L-329


Table: S_Quad_Index 

This table is required for all preliminary or final DFIRM databases. 

The S_Quad_Index table contains information about the US Geological Survey (USGS) 7.5-
Minute Series Topographic Quadrangle maps that cover the study area. While USGS 
quadrangles do not meet the Federal Emergency Management (FEMA) digital base map 
standards, they are often useful as a supplementary reference source. The quadrangle 
information is provided as a convenience to users who may want to cross-reference this map 
series. A spatial file with locational information also corresponds with this data table. 

The spatial entities representing the USGS quadrangles are polygons. Each polygon corresponds 
to the neatline of a USGS map. 

This is a Standard DFIRM Database table. 

The S_Quad_Index table contains the following elements. 

QUAD_ID R S Primary key for table lookup. Assigned by table creator. 

QUAD_NO R S Quad Number. This is the eight-digit USGS alphanumeric 
quadrangle identifier. The list of values for each state is published 
by USGS in the State Indexes to Topographic and Other Map 
Coverage. This item is composed of three components: the latitude, 
rounded down to the nearest whole degree, of the 7.5-minute 
quadrangle map sheet; the longitude, rounded down to the nearest 
whole degree, of the 7.5-minute quadrangle map sheet; and the 
alphanumeric map sheet identifier used by USGS (i.e., A1 through 
H8). 

QUAD_NM R S Quad Name. This is the name of the quadrangle that is assigned by 
USGS. 

SOURCE_CIT R S Source Citation. Abbreviation used in the metadata file when 
describing the source information for S_Quad_Index table. 


Table: S_Quad_Index

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
QUAD_ID R S text 11 string 11 character 11 11 character 11 
QUAD_NO R S text 8 string 8 character 8 8 character 8 
QUAD_NM R S text 50 string 50 character 50 50 character 50 
SOURCE_CIT R S text 11 string 11 character 11 11 character 11 

L-331


Table: S_Riv_Mrk 

This table is required if the Flood Insurance Rate Map (FIRM) shows river distance marks. 

The S_Riv_Mrk table contains information about the River Marks shown on the hardcopy FIRM 
if applicable. A spatial file with locational information also corresponds with this data table. 

The spatial entities representing the river marks are points. The points are generally located 
along side of the river at regular intervals. 

This is a Standard DFIRM Database table. 

The S_Riv_Mrk table contains the following elements.
RIV_MRK_ID R S Primary key for table lookup. Assigned by table creator.

START_ID R S Start Identification. A code that provides a link to a point in the 
L_Stn_Start table at which the river mark distances start. 

RIV_MRK_NO R S River Mark Number. This attribute usually represents the distance 
from a known point (identified by START_ID), such as the 
confluence with another river, to the current river mark. This is the 
value shown next to the river mark on the FIRM. 

SOURCE_CIT R S Source Citation. Abbreviation used in the metadata file when 
describing the source information for the S_Riv_Mrk table. 


Table: S_Riv_Mrk

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
RIV_MRK_ID R S text 11 string 11 character 11 11 character 11 
START_ID R S text 11 string 11 character 11 11 character 11 
RIV_MRK_NO R S text 6 string 6 character 6 6 character 6 
SOURCE_CIT R S text 11 string 11 character 11 11 character 11 

L-333


Table: S_Shore_Ln 

This table is required for coastal modeling studies. 

The S_Shore_Ln table contains information about the shoreline used in the coastal flood hazard 
model. Typically, the S_Shore_Ln represents to 0.0-foot elevation contour. The S_Shore_Ln 
shoreline may not be shown on the FIRM but must be archived for informational purposes. The 
mapped shoreline is stored in the S_Wtr_Ln table of the standard DFIRM database. A spatial 
file with locational information also corresponds with this data table. 

The spatial elements representing the shorelines are lines. 

This is an Enhanced DFIRM Database table. 

The S_Shore_Ln table contains the following elements. 

SHR_LN_ID R E Primary key for table lookup. Assigned by table creator. 

SHRLN_TYP R E Shoreline Type. This value describes the criteria used in 
determining the shoreline in coastal flood hazard models. 
Acceptable values for this table are listed in the D_Shr_Typ table. 

V_DATUM R E Vertical Datum. This is the vertical datum of the printed FIRM. 
The vertical datum describes the reference surface from which 
elevation on the map is measured. Normally this would be North 
American Vertical Datum of 1988 for new studies. Acceptable 
values for this field are listed in the D_V_Datum table. 

SOURCE_CIT R E Source Citation. Abbreviation used in the metadata file when 
describing the source information for the S_Shore_Ln table. 


Table: S_Shore_Ln

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
SHR_LN_ID R E text 11 string 11 character 11 11 character 11 
SHRLN_TYP R E text 30 string 30 character 30 30 character 30 
V_DATUM R E text 6 string 6 character 6 6 character 6 
SOURCE_CIT R E text 11 string 11 character 11 11 character 11 

L-335


Table: S_Stn_Start 

This table is required when the geographic location of station start points exist. 

The S_Stn_Start contains information about station points. These points indicate the reference 
point that was used as the origin for distance measurements along streams and rivers. This table 
links to descriptive information in the L_Stn_Start table. A spatial file with locational 
information also corresponds with this data table. 

The spatial entity representing station starting locations are points. The point should be located 
on the stream centerline at the place where the measurements begin. This point may be outside 
the jurisdiction mapped in some cases. The location of the stationing start for a group of cross 
sections is normally referenced as a note on the floodway data table and on the flood profiles. 
Generally, all the cross sections for a particular reach are reference to the same starting point. 

This is an Enhanced DFIRM Database table. 

The S_Stn_Start table contains the following elements. 

STRT_PT_ID R E Primary key for this table. Assigned by table creator. 

START_ID R E Start Identification. This is a link to the station start lookup table. 
The station start describes the origin for the measurements in the 
STREAM_STN field. This field must contain a number that links 
to a unique value in the START_ID field in the L_Stn_Start table. 

SOURCE_CIT R E Source Citation. Abbreviation used in the metadata file when 
describing the source information for S_Stn_Start. 


Table: S_Stn_Start

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
STRT_PT_ID R E text 11 string 11 character 11 11 character 11 
START_ID R E text 11 string 11 character 11 11 character 11 
SOURCE_CIT R E text 11 string 11 character 11 11 character 11 

L-337


Table: S_Subbasins 

This table is required for all studies with new or revised hydrologic data. 

The S_Subbasins table contains data specific to each subbasin in the hydrologic analysis, 
including the subbasins relationship to the hydrologic network. The subbasin may be the 
subbasin specific to a detailed hydrologic model. It may also correspond to the drainage area 
used in a regression analysis, or to the drainage area for a stream gage. A spatial file with 
locational information also corresponds with this data table. 

The spatial elements representing the subbasins are polygons. In some cases the extent of these 
polygons may overlap, for example, cumulative subbasin areas for a regression analysis. 

This is an Enhanced DFIRM Database table.
The S_Subbasins table contains the following elements.
SUBBAS_ID R E Primary key for this table. Assigned by table creator.

SUBBAS_NM R E Name of subbasin. 

NODE_ID R E Node Identification. A code that provides a link to a valid entry 
from the S_Nodes table. ID for the load/outflow point (pourpoint) 
for the subbasin. 

SOURCE_CIT R E Source Citation. Abbreviation used in the metadata file when 
describing the source information for S_Subbasins. 


Table: S_Subbasins

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
SUBBAS_ID R E text 11 string 11 character 11 11 character 11 
SUBBAS_NM R E text 254 string 254 character 254 254 character 254 
NODE_ID R E text 11 string 11 character 11 11 character 11 
SOURCE_CIT R E text 11 string 11 character 11 11 character 11 

L-339


Table: S_Trnsport_Ln 

This table or an equivalent that is fully documented is required for all Digital Flood Insurance 
Rate Map databases that use a vector rather than raster base map data. 

The S_Trnsport_Ln table contains information about the linear base map transportation features 
such as roads, railroads, and airports. A spatial file with locational information also corresponds 
with this data table. 

The spatial entities representing linear transportation features are normally lines. However, if the 
available transportation data depict roads as polygons, polygon representation is acceptable. In 
general, the transportation table structure is fairly flexible depending on the format of the data 
available for the map. The Federal Emergency Agencys (FEMAs) objective is to have spatially 
accurate base map data to which the flood hazard information is referenced. Users must be able 
to identify the names of roads, railroads and other major features in or near the special flood 
hazard area. If these objectives are met, then almost any file structure is acceptable. Road 
centerlines or edge of pavement files are both acceptable, provided that they meet the FEMA 
base map standard. With some data structures, it may not be practical to assign feature names or 
other attributes to each spatial entity. While these attributes are desirable, FEMA recognizes that 
they may not always be easily available. This is acceptable because the S_Label_Pt and 
S_Label_Ld tables will identify the names of all of the important features in or near the SFHA. 

This is a Standard DFIRM Database table. 

The S_Trnsport_Ln table contains the following elements. 

TRANS_ID R S Primary key for table lookup. Assigned by table creator. 

TRANS_TYP R S Transportation Feature Type. These line types indicate how the 
feature must be depicted on the hardcopy Flood Insurance Rate 
Map. Acceptable values for this field are listed in the 
D_Trans_Typ table. 

RD_STAT R S Road Status. Acceptable values for this field are listed in the 
D_Rd_Stat table. 

PREFIX A S Prefix of the Feature Name. Not all features will have an entry in 
this attribute. Valid entries might include N for a transportation 
feature named N Main Street. 

FEAT_NM1 R S Feature Name 1. This is the primary name of the feature. For areas 
that have more than one name, this would be the primary name with 
subsequent names shown in fields below. Route numbers and 
Intercoastal Waterway would also be included in this item. 


NM_TYP R S Name Type. Transportation feature name type. Valid entries 
include items such as road, street, or avenue. Acceptable values for 
this field are listed in the D_Nm_Typ table. 

SUFFIX A S Suffix of the Feature Name. Not all features will have an entry in 
this attribute. Valid entries might include NW for a transportation 
feature named Main Street NW. 

FEAT_NM2 A S Feature Name 2. This is the secondary name of the feature. 

FEAT_NM3 A S Feature Name 3. This is the tertiary name of the feature. 

SOURCE_CIT R S Source Citation. Abbreviation used in the metadata file when 
describing the source information for the S_Trnsport_Ln table. 


Table: S_Trnsport_Ln

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
TRANS_ID R S text 11 string 11 character 11 11 character 11 
TRANS_TYP R S text 50 string 50 character 50 50 character 50 
RD_STAT R S text 20 string 20 character 20 20 character 20 
PREFIX A S text 50 string 50 character 50 50 character 50 
FEAT_NM1 R S text 100 string 100 character 100 100 character 100 
NM_TYP R S text 20 string 20 character 20 20 character 20 
SUFFIX A S text 50 string 50 character 50 50 character 50 
FEAT_NM2 A S text 100 string 100 character 100 100 character 100 
FEAT_NM3 A S text 100 string 100 character 100 100 character 100 
SOURCE_CIT R S text 11 string 11 character 11 11 character 11 

L-342


Table: S_Water_Gage 

This table is required when non-rain gages are used in developing the hydrologic analysis. A 
spatial file with locational information also corresponds with this data table. 

The spatial elements representing the water gages are points. 

This is an Enhanced DFIRM Database table.
The S_Water_Gage table contains the following elements.
GAG_WTR_ID R E Primary key for this table. Assigned by table creator.

GAGE_ID R E Gage Identification. Assigned by the agency maintaining the gage.
AGENCY R E Agency. Name of the agency maintaining the gage.

GAGE_TYPE R E Gage Type. This attribute establishes the gage type. Values 
include flow, stage, wind direction, wind speed, wave, and tide. 
Acceptables values for this table are listed in the D_Gage table. 

REC_INTVL R E Recording Interval. Recording interval for the gage. 

TIME_UNIT R E Recording Interval Time Unit. This attribute establishes the unit of 
measure of the recording interval. Acceptable values for this table 
are listed in the D_Time_Units table. 

CASE_NO R E FEMA Case Number. The case number for the water gage links to 
the L_Case_Info table. 

START_PD R E Start Period. This value is the start of the earliest period of record 
used in the gage analysis. 

END_PD R E End Period. This value is the end of the latest period of record used 
in the gage analysis. 

SOURCE_CIT R E Source Citation. Abbreviation used in the metadata file when 
describing the source information for S_Water_Gage. 


Table: S_Water_Gage

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
GAG_WTR_ID R E text 11 string 11 character 11 11 character 11 
GAGE_ID R E text 25 string 25 character 25 25 character 25 
AGENCY R E text 150 string 150 character 150 150 character 150 
GAGE_TYPE R E text 40 string 40 character 40 40 character 40 
REC_INTVL R E text 11 string 11 character 11 11 character 11 
TIME_UNIT R E text 20 string 20 character 20 20 character 20 
CASE_NO R E text 12 string 12 character 12 12 character 12 
START_PD R E date/time 8 yyyymmdd 00/00/0000 date date 8 10 date 
END_PD R E date/time 8 yyyymmdd 00/00/0000 date 11 date 8 10 date 11 
SOURCE_CIT R E text 11 string 11 character 11 11 character 11 

L-344


Table: S_Wtr_Ar 

This table is required for any Digital Flood Insurance Rate Map (DFIRM) database where vector 
surface water features are shown on the Flood Insurance Rate Map (FIRM) and some of these 
features are represented as polygons in the spatial data. Vector streams must always be shown 
with a vector base map. They may also be shown on raster base maps. 

The S_Wtr_Ar table contains information about surface water area features. A spatial file with 
locational information also corresponds with this data table. 

The spatial elements representing surface water area features are polygons. Normally lakes, 
ponds and streams wide enough to show both channel banks will be represented as polygons. 
However, the main purpose of the S_Wtr_Ar table and the S_Wtr_Ln table are to provid e a 
cartographic depiction of the surface water features for visual interpretation of the mapping data. 
As a result, the method for structuring surface water features as lines or polygons is very flexible. 
Surface water features may appear in either the S_Wtr_Ar table or the S_Wtr_Ln table or both. 
However, features that appear in both must match exactly. The hydrologic structure of the 
stream network will be represented by tables in the Enhanced DFIRM Database. 

In general, the surface water table struc ture is fairly flexible depending on the format of the data 
available for the map. The Federal Emergency Management Agencys (FEMAs) objective is to 
have spatially accurate surface water feature data to which the flood hazard information is 
referenced. Users must be able to identify the names of flooding sources and other important 
surface water features. If these objectives are met, then almost any file structure is acceptable. 
Streams, rivers and lakes may be represented as either polygons or lines. With some data 
structures, it may not be practical to assign feature names or other attributes to each spatial 
entity. While these attributes are desirable, FEMA recognizes that they may not always be easily 
available. This is acceptable because the S_Label_Pt and S_Label_Ld tables will identify the 
names of flooding sources and other important surface water features. 

This is a Standard DFIRM Database table. 

The S_Wtr_Ar table contains the following elements. 

WTR_AR_ID R S Primary key for table lookup. Assigned by table creator. 

WATER_TYP R S Surface Water Feature Type. This type value describes the 
classification of the surface water feature. Valid entries include 
items such as lake, retention pond, and reservoir. Acceptable 
values for this field are listed in the D_Water_Typ table. 

WTR_NM R S Surface Water Feature Name. This is the formal name of the 
surface water feature, as it will appear on the hardcopy FIRM. 

SOURCE_CIT R S Source Citation. Abbreviation used in the metadata file when 
describing the source information for the S_Wtr_Ar table. 


Table: S_Wtr_Ar

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
WTR_AR_ID R S text 11 string 11 character 11 11 character 11 
WATER_TYP R S text 40 string 40 character 40 40 character 40 
WTR_NM R S text 100 string 100 character 100 100 character 100 
SOURCE_CIT R S text 11 string 11 character 11 11 character 11 

L-346


Table: S_Wtr_Ln 

This table is required for any Digital Flood Insurance Rate Map (DFIRM) database where vector 
surface water features are shown on the Flood Insurance Rate Map (FIRM) and some of these 
features are represented as lines in the spatial data. Vector streams must always be shown with a 
vector base map. They may also be shown on raster base maps. 

The S_Wtr_Ln table contains information about surface water linear features. A spatial file with 
locational information also corresponds with this data table. 

The spatial elements representing surface water line features are lines. Normally stream 
centerlines will be represented as line features. However, the main purpose of the S_Wtr_Ar 
table and the S_Wtr_Ln table is to provide a cartographic depiction of the surface water features 
for visual interpretation of the mapping data. As a result, the method for structuring surface 
water features as lines or polygons is very flexible. Lake shorelines and stream channel banks 
used to show lakes and wide rivers are usually represented as polygons. However, they may be 
represented as lines based on the structure of the data received and the Mapping Partners 
discretion. Surface water features may appear in either the S_Wtr_Ar table or the S_Wtr_Ln 
table or both. However, features that appear in both must match exactly. The hydrologic 
structure of the stream network will be represented by tables in the Enhanced DFIRM Database. 

In general, the surface water table structure is fairly flexible depending on the format of the data 
available for the map. The Federal Emergency Management Agencys (FEMAs) objective is to 
have spatially accurate surface water feature data to which the flood hazard information is 
referenced. Users must be able to identify the names flooding sources and other important 
surface water features. If these objectives are met, then most any file structure is acceptable. 
Streams, rivers and lakes may be represented as polygons or lines. With some data structures, it 
may not be practical to assign feature names or other attributes to each spatial entity. While 
these attributes are desirable, FEMA recognizes that they may not always be easily available. 
This is acceptable because the S_Label_Pt and S_Label_Ld tables will identify the names of 
flooding sources and other important surface water features. 

This is a Standard DFIRM Database table. 

The S_Wtr_Ln table contains the following elements. 

WTR_LN_ID R S Primary key for table lookup. Assigned by table creator. 

WATER_TYP R S Surface Water Feature Type. The type value describes the kind of 
watercourse represented. Valid entries include items such as 
stream/river, channel, and shoreline/coastline. Acceptable values 
for this field are listed in the D_Water_Typ table. 

CHAN_REP R S Channel Representation. Single means linear water features 
represented by a centerline. Double means linear water features 
represented by shorelines or channel banks. Acceptable values for 
this field are listed in the D_Chn_Rep table. 


WTR_NM R S Surface Water Feature Name. This is the formal name of the 
surface water feature, as it will appear on the hardcopy FIRM. 

SOURCE_CIT R S Source Citation. Abbreviation used in the metadata file when 
describing the source information for the S_Wtr_Ln table. 


Table: S_Wtr_Ln

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
WTR_LN_ID R S text 11 string 11 character 11 11 character 11 
WATER_TYP R S text 40 string 40 character 40 40 character 40 
CHAN_REP R S text 20 string 20 character 20 20 character 20 
WTR_NM R S text 100 string 100 character 100 100 character 100 
SOURCE_CIT R S text 11 string 11 character 11 11 character 11 

L-349


Table: S_XS 

This table is required for any Digital Flood Insurance Rate Map database where cross sections 
are shown on the Flood Insurance Rate Map (FIRM). Normally any FIRM that has associated 
flood profiles has cross sections. 

The S_XS table contains information about cross section lines. A spatial file with locational 
information also corresponds with this data table. These lines represent the locations of channel 
surveys performed for input into the hydraulic model used to calculate flood elevations. These 
locations are also shown on the Flood Profiles in the Flood Insurance Study (FIS) report and can 
be used to cross reference the Flood Profiles to the planimetric depiction of the flood hazard. All 
cross sections for which a spatial location is available should be included in this table. 

The spatial elements representing cross sections are lines generally extending from outside the 
floodplain, across the entire floodplain and out the other side. Each cross section should be 
represented by a single line feature without the hexagons shown on each end on the hardcopy 
map. The location and shape of the lines should depict as accurately as possible the position of 
the cross section used. 

This is a modified Standard DFIRM Database table that includes Standard DFIRM Database 
items and Enhanced Database items. All items after SOURCE_CIT are Enhanced. The 
Enhanced DFIRM Database must contain all modeled cross sections, whether they are printed on 
the FIRM or not. 

The S_XS table contains the following elements. 

XS_LN_ID R S Primary key for table lookup. Assigned by table creator. 

XS_LTR A S Cross-Section Letter. The letter or number that is assigned to the 
cross section on the hardcopy FIRM and in the FIS report. This 
attribute is blank if the cross section is not shown on the FIRM. For 
a digital conversion, only cross sections that are shown on the 
FIRM will be available. 

START_ID R S Start Identification. This is a link to the station start lookup table. 
The station start describes the origin for the measurements in the 
STREAM_STN field. This field should contain a number that links 
to a unique value in the START_ID field in the L_Stn_Start table. 

STREAM_STN R S Stream Station. This is the measurement along the stream to the 
cross-section location. Normally this information is available in the 
Floodway Data table in the FIS report. When no Floodway Data 
table is published, this value can be read from the horizontal scale 
of the flood profile. The units are clarified in the description in the 
START_DESC field in the L_Stn_Start table. 


XS_LN_TYP R S Cross-Section Line Type. This attribute should contain 
LETTERED for cross sections that are shown on the hardcopy 
FIRM. If the cross section will not be shown on the hardcopy 
FIRM, this attribute should contain NOT LETTERED to indicate 
that the cross section is part of the backup data for the study, but is 
not shown on the FIRM. 

WTR_NM R S Surface Water Feature Name. This is the formal name of the 
surface water feature, as it will appear on the hardcopy FIRM. 

WSEL_REG R S Regulatory Water-Surface Elevation for the 1-Percent-Annual-
Chance Flood Event. This is the precise water surface elevation of 
the base flood calculated at this cross section. This elevation 
exactly matches the elevation of the base flood in the Flood Profiles 
and the Floodway Data table. This number is determined during the 
engineering analysis for the study. This value should match the 
regulatory column in the Floodway Data table in the FIS report or 
the elevation from the corresponding flood profile if no Floodway 
Data table is published. 

LEN_UNIT R S Water Surface Elevation Units. This unit indicates the 
measurement system used for the water surface elevation. 
Normally this would be feet. Acceptable values for this field are 
listed in the D_Length_Units table. 

V_DATUM R S Vertical Datum. The vertical datum indicates the reference surface 
from which the flood elevations are measured. Normally this would 
be North American Vertical Datum of 1988 for new studies. 
Acceptable values for this field are listed in the D_V_Datum table. 

SOURCE_CIT R S Source Citation. Abbreviation used in the metadata file when 
describing the source information for the S_XS table. Table: 

BED_ELEV R E Streambed Elevation. The elevation of the streambed at this cross 
section as shown on the Flood Profile in the FIS. 

TOP_WIDTH R E Top Width. Width of the floodway at this cross section as shown in 
the Floodway Data table in the FIS. 

XS_AREA R E Cross Section Area. Area of the cross section underwater for the 
width of the floodway as shown in the Floodway Data table in the 
FIS. 

AREA_UNIT R E Area Unit. This unit specifies the areal unit for the area of the cross 
section underwater for the width of the floodway. Acceptable 
values for this field are listed in the D_Area_Units table. 


VELOCITY R E Mean Velocity. The mean velocity of the floodway at this cross 
section as shown in the Floodway Data table in the FIS. 

VEL_UNIT R E Velocity Measurement. This unit specifies the unit of measurement 
for the velocity of the floodway. Acceptable values for this field 
are listed in the D_Velocity_Units table. 


Table: S_XS

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
XS_LN_ID R S text 11 string 11 character 11 11 character 11 
XS_LTR A S text 12 string 12 character 12 12 character 12 
START_ID R S text 11 string 11 character 11 11 character 11 
STREAM_STN R S text 12 string 12 character 12 12 character 12 
XS_LN_TYP R S text 20 string 20 character 20 20 character 20 
WTR_NM R S text 100 string 100 character 100 100 character 100 
WSEL_REG R S 
number 
(double) 8 2 number 13 2 numeric 8 13 2 decimal 15 2 
LEN_UNIT R S text 20 string 20 character 20 20 character 20 
V_DATUM R S text 6 string 6 character 6 6 character 6 
SOURCE_CIT R S text 11 string 11 character 11 11 character 11 
BED_ELEV R E 
number 
(double) 8 2 number 13 2 numeric 8 13 2 decimal 15 2 
TOP_WIDTH R E number 8 2 number 13 2 numeric 8 13 2 decimal 15 2 

L-353


(double) 
XS_AREA R E 
number 
(double) 8 2 number 13 2 numeric 8 13 2 decimal 15 2 
AREA_UNIT R E text 20 string 20 character 20 20 character 20 
VELOCITY R E 
number 
(double) 8 2 number 13 2 numeric 8 13 2 decimal 15 2 
VEL_UNIT R E text 20 string 20 character 20 20 character 20 

L-354


Table: Study_Info 

This table is required for all draft Digital Flood Insurance Rate Map data. 

The Study_Info table contains details about the study such as the study name, datum, projection, 
etc. There is normally only one record in this table for each Flood Insurance Rate Map (FIRM). 

This is a modified Standard DFIRM Database table that includes Standard DFIRM Database 
items and Enhanced Database items. The item STUDY_ZIP is Enhanced. 

The Study_Info table contains the following elements. 

STD_NFO_ID R S Primary key for table lookup. Assigned by table creator. 

STUDY_PRE A S Study Prefix. This is the prefix of the study name such as City of 
or Town of. This field is applicable for single jurisdiction maps 
where the type of jurisdiction precedes the name of the jurisdiction 
in the map title. For county-wide maps or maps of the 
unincorporated portions of a county, this field is NULL. 

STUDY_NM R S Study Name. This attribute contains the main portion of the study 
name, which is shown in the title block of the hardcopy FIRM. For 
county-wide FIRMs, or FIRMs for the unincorporated portions of 
counties, the name should include the county or county equivalent 
descriptor (e.g. Washington County or Iberia Parish). 

STATE_NM R S State Name. This attribute contains the state name for the study and 
is shown in the title block of the hardcopy FIRM. 

CNTY_NM R S County Name. This is the county (or county equivalent) name that 
the study falls within. The name should include the county or 
county equivalent descriptor (e.g. Washington County or Iberia 
Parish). The county name is also shown in the title block section of 
the hardcopy FIRM. 

JURIS_TYP A S Political Jurisdiction Type. This attribute contains entries such as 
Unincorporated Areas or All Jurisdictions or and Incorporated 
Areas. This field is applicable when the type of map is 
Unincorporated Areas or All Jurisdictions or and Incorporated 
Areas. For a single jurisdiction map, this field is NULL. If there 
are data in this attribute, it is also shown in the title block section of 
the hardcopy FIRM. 

LG_PAN_NO R S Largest Panel Number. This is the highest panel number shown on 
the FIRM Index for the area mapped. This number is shown in the 
title block section of the hardcopy FIRM. 


OPP_TF R S Only Panel Printed. This field is True only if the study has only 
one printed panel. Enter T for true or F for false. 

H_DATUM R S Horizontal Datum. Valid entries for this attribute include North 
American Datum of 1927 or North American Datum of 1983 
(NAD83). This is the horizontal datum used for the printed FIRM. 
The horizontal datum describes the reference system on which the 
horizontal coordinate information shown on the FIRM is based. 
NAD83 is the preferred horizontal datum. 

V_DATUM R S Vertical Datum. This is the vertical datum of the printed FIRM. 
The vertical datum describes the reference surface from which 
elevation on the map is measured. Normally this would be North 
American Vertical Datum of 1988 for new studies. Acceptable 
values for this field are listed in the D_V_Datum table. 

PROJECTION R S Map Projection used for hardcopy FIRM publication. The 
preferred projection is Universal Transverse Mercator (UTM). If a 
State Plane coordinate system and associated projection is used, this 
field should include the name of the projection, the state and the 
zone (e.g., Lambert Conformal Conic, Virginia North Zone). 

PROJ_ZONE A S Projection Zone. When using many map projections and coordinate 
systems, there is a zone associated with the area. This field is 
populated based on the projection selected for the Final hardcopy 
map production. Applies if the projection used has a zone 
parameter such as UTM or state plane. The zone should be stated 
as the appropriate Federal Information Processing Standard zone or 
FIPSZONE. 

CW_TF R S Countywide, true/false. This attribute is true if the hardcopy FIRM 
includes all incorporated areas and any unincorporated areas of the 
county. Enter T for true or F for false. 

CBRS_PHONE A S Coastal Barrier Resources System (CBRS) Phone number. This is 
the phone number for the contact person/office for the CBRS 
legislative area. Applies if the FIRM contains CBRS areas. Enter 
the phone number as a ten-digit numeric string with hyphens in the 
following format, 000-000-0000. 

CBRS_REG A S CBRS Coordinators region. This attribute contains the Fish and 
Wildlife Service (FWS) region within which the FIRM is located. 
Applies if the FIRM contains CBRS areas. 

RTROFT_TF R S Retrofit, True/False. The Retrofit attribute should be True if older 
study data is used with updated stream location data. If flood 
features were adjusted to fit new stream locations due to better base 


map information this attribute would be true. Enter T for true or 
F for false. 

META_NM R S Metadata File Name. This attribute stores the name of the metadata 
file. The file should be named 
<ST_FIPS><PCOMM>_<EFF_DATE>_metadata.txt; where 
ST_FIPS is the two digit state FIPS code; PCOMM is the four digit 
community or county identifcation number; and EFF_DATE is the 
effective date of the study. If the study is not yet effective, the 
effective date, <EFF_DATE>, should be replaced with the word 
PRELIM. 

STUDY_ZIP A E Name of the Study Zipfile. This attribute stores the path/filename 
of the zipped file that contains the FIS report or auxiliary data that 
is relevant to the entire study. 


Table: Study_Info

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
STD_NFO_ID R S text 11 string 11 character 11 11 character 11 
STUDY_PRE A S text 20 string 20 character 20 20 character 20 
STUDY_NM R S text 50 string 50 character 50 50 character 50 
STATE_NM R S text 50 string 50 character 50 50 character 50 
CNTY_NM R S text 50 string 50 character 50 50 character 50 
JURIS_TYP A S text 50 string 50 character 50 50 character 50 
LG_PAN_NO R S text 4 string 4 character 4 4 character 4 
OPP_TF R S text 1 string 1 character 1 1 character 1 
H_DATUM R S text 10 string 10 character 10 10 character 10 
V_DATUM R S text 6 string 6 character 6 6 character 6 
PROJECTION R S text 50 string 50 character 50 50 character 50 
PROJ_ZONE A S text 4 string 4 character 4 4 character 4 
CW_TF R S text 1 string 1 character 1 1 character 1 
CBRS_PHONE A S text 15 000-000-0000 000\-000\-0000 string 15 character 15 15 character 15 

L-358


CBRS_REG A S text 1 string 1 character 1 1 character 1 
RTROFT_TF R S text 1 string 1 character 1 1 character 1 
META_NM R S text 50 string 50 character 50 50 character 50 
STUDY_ZIP A E text 254 string 254 character 254 254 character 254 

L-359


Table: L_Aux_Data 

This table is required when the data developer wishes to document additional data sources used 
in developing the study. The table may be used to document other data sets such as topography, 
soils, land use, coastal roughness, etc. 

This is an Enhanced DFIRM Database table.
The L_Aux_Data table contains the following elements.
DATA_ID R E Primary key for this table. Assigned by table creator.

CASE_NO R E FEMA Case Number. The case number for the auxiliary data links 
to the L_Case_Info table. 

DATA_DATE R E Date the data was prepared (e.g., date of file originally supplied by 
Mapping Partner). 

DATA_TYPE R E Description of data set. 

ORG_NAME A E Organization which generated/supplied the data. 
CONTACT A E Name of contact person. 

TITLE A E Title of contact person. 

PHONE A E Phone number of contact person/organization. Enter the phone 
number as a ten-digit numeric string with hyphens in the following 
format, 000-000-0000. 

ADDRESS1 A E Line 1 of mailing address of contact person/organization.

ADDRESS2 A E Line 2 of mailing address of contact person/organization.
ADDRESS3 A E Line 3 of mailing address of contact person/organization.
CITY A E City of contact person/organization.

STATE A E State/Territory/Commonwealth of contact person/organization.
ZIP A E Postal ZIP code of contact person/organization.

FILE_NM R E Name of accompanying data file.
META_NM R E Name of metadata file that describes the accompanying dataset. 


Table: L_Aux_Data

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
DATA_ID R E text 11 string 11 character 11 11 character 11 
CASE_NO R E text 12 string 12 character 12 12 character 12 
DATA_DATE R E date/time 8 yyyymmdd 00/00/0000 date date 8 10 date 
DATA_TYPE R E text 254 string 254 character 254 254 character 254 
ORG_NAME A E text 100 string 100 character 100 100 character 100 
CONTACT A E text 50 string 50 character 50 50 character 50 
TITLE A E text 25 string 25 character 25 25 character 25 
PHONE A E text 15 000-000-0000 000\-000\-0000 string 15 character 15 15 character 15 
ADDRESS1 A E text 50 string 50 character 50 50 character 50 
ADDRESS2 A E text 50 string 50 character 50 50 character 50 
ADDRESS3 A E text 50 string 50 character 50 50 character 50 
CITY A E text 50 string 50 character 50 50 character 50 
STATE A E text 50 string 50 character 50 50 character 50 
ZIP A E text 10 string 10 character 10 10 character 10 

L-361


FILE_NM R E text 254 string 25 character 25 25 character 25 
META_NM R E text 50 string 50 character 50 50 character 50 

L-362


Table: L_Case_Info 

This table is required for all studies with new or revised hydrologic data. 

The L_Case_Info table is a lookup table that contains data specific to the study, including FEMA 
Case information and general hydrologic and/or hydraulic backup information. The fields are 
populated by the Mapping Partner who creates the database. If a Case Number is not available at 
the time the table is populated, the Mapping Partner shall use a temporary unique identification 
number. 

This is an Enhanced DFIRM Database table. 

The L_Case_Info table contains the following elements. 

CASE_NO R E Primary key for this table. FEMA Case Number for study. Used to 
link to archived electronic and hardcopy data, and to link to various 
hydrologic and hydraulic data tables. 

CASE_DESC R E General description of the study, for example, the study location 
and method(s) used. 

CASE_ZIP R E Name of the Case Zipfile. This attribute stores the file 
name/pathway of the zipped file that contains engineering support 
data associated with the Case. 

STD_NFO_ID R E Study Information Identification. A code that provides a link to a 
valid entry from the Study_Info table. 

EFF_DATE R E Effective date of the Case. 


Table: L_Case_Info

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
CASE_NO R E text 12 string 12 character 12 12 character 12 
CASE_DESC R E text 254 string 254 character 254 254 character 254 
CASE_ZIP R E text 254 string 254 character 254 254 character 254 
STD_NFO_ID R E text 11 string 11 character 11 11 character 11 
EFF_DATE R S date/time 8 yyyymmdd 00/00/0000 date date 8 10 date 

L-364


Table: L_Comm_Info 

This table is required for all preliminary or final DFIRM databases. 

The L_Comm_Info table is a lookup table that contains community map repository details and 
map history information that is shown on the Flood Insurance Rate Map (FIRM) legend or index. 
This table will include any community that has a CID; even if it is considered non-floodprone or 
non-participationg. Communities that do not have a CID issued by FEMA, or are not included 
within the area of the data submittal, will not appear in this table. The not populated values, 
that are described in sections L.2.5.10 and L.3.5.11, may be used to fill in some of the required 
fields when necessary. There is normally one record in this table for each community mapped 
on the FIRM. 

This is a Standard DFIRM Database table. 

The L_Comm_Info table contains the following elements. 

COM_NFO_ID R S Primary key for table lookup that links to the S_Pol_Ar table. 
Value in this field must match the values COM_NFO_ID field of 
the S_Pol_Ar table. 

REPOS_ADR1 R S First line of the mailing or street address for the map repository. 
The map repository is the office the community has designated as 
responsible for maintaining copies of all the flood hazard 
information the Federal Emergency Management Agency (FEMA) 
publishes for the community. The public may view copies of the 
current effective information at the map repository. This 
information is also displayed in the FIRM legend or index. For 
example, this line might read Division of Community and 
Economic Development. 

REPOS_ADR2 A S Second line of the mailing or street address for the map repository. 
This information is also displayed in the FIRM legend or index. 
For example, this line might read 226 W. Fourth Street. This field 
is applicable if the map repository address requires more than one 
line. 

REPOS_ADR3 A S Third line of the mailing or street address for the map repository. 
This information is also displayed in the FIRM legend or index. 
For example, this line might read Suite 200. This field is 
applicable if address requires additional space. 

REPOS_CITY R S City portion of the mailing or street address for the map repository. 
This information is also displayed in the FIRM legend or index. 
For example, this line might read Springfield. 


REPOS_ST R S State portion of the mailing or street address for the map repository. 
This information is also displayed in the FIRM legend or index. 
The full name of the state should be provided. For example, this 
line might read ILLINOIS. 

REPOS_ZIP R S ZIP Code portion of the mailing or street address for the map 
repository. This information is also displayed in the FIRM legend 
or index. For example, this line might read 62269. 

IN_ID_DAT R S Initial identification date for the community as shown on the FIRM 
legend, index, or Flood Insurance Study (FIS) report. This 
information can also be obtained from FEMA. See Appendix K of 
these Guidelines for more detailed information about map dates. 

IN_NFIP_DT R S Initial date of the first National Flood Insurance Program map 
published by FEMA for this community. This can be obtained 
from the FIRM legend, index, or FIS report. This information can 
also be obtained from FEMA. See Appendix K of these Guidelines 
for more detailed information about map dates. 

IN_FRM_DAT R S Initial date FIRM was created. This can be obtained from the 
FIRM legend, index, or FIS report. This information can also be 
obtained from FEMA. See Appendix K of these Guidelines for 
more detailed information about map dates. 

RECENT_DAT A S Most recent panel date. This can be obtained from the FIRM Index 
or the FEMA Community Status book at www.fema.gov/msc. 
This field is only populated for final DFIRM Databases. See 
Appendix K of these Guidelines for more detailed information 
about map dates. 


Table: L_Comm_Info

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
COM_NFO_ID R S text 11 string 11 character 11 11 character 11 
REPOS_ADR1 R S text 50 string 50 character 50 50 character 50 
REPOS_ADR2 A S text 50 string 50 character 50 50 character 50 
REPOS_ADR3 A S text 50 string 50 character 50 50 character 50 
REPOS_CITY R S text 50 string 50 character 50 50 character 50 
REPOS_ST R S text 50 string 50 character 50 50 character 50 
REPOS_ZIP R S text 9 string 9 character 9 9 character 9 
IN_ID_DAT R S date/time 8 yyyymmdd 00/00/ 0000 date date 8 10 date 
IN_NFIP_DT R S date/time 8 yyyymmdd 00/00/0000 date date 8 10 date 
IN_FRM_DAT R S date/time 8 yyyymmdd 00/00/0000 date date 8 10 date 
RECENT_DAT A S date/time 8 yyyymmdd 00/00/0000 date date 8 10 date 

L-367


Table: L_Cst_Model 

This table is completed if coastal engineering analysis was performed. It is required for new 
coastal studies It is not required for digital conversions of effective flood hazard information 
because considerable additional effort may be required to research the applicable models. 

The L_Cst_Model table is a lookup table that contains information about the coastal models that 
were used during the engineering analysis. 

This is an Enhanced DFIRM Database table. 

The L_Cst_Model table contains the following elements. 

CST_MDL_ID R E Primary key for table lookup that links to the S_Cst_Tsct_Ln table. 
Value in this field should match the values in the CST_MDL_ID 
field of the S_Cst_Tsct_Ln table. 

WTR_NM R E Surface Water Feature Name. This is the formal name of the 
surface water feature, as it will appear on the hardcopy FIRM. 

CASE_NO R E Case Number Identification. This field is populated by a linking 
element to the L_Case_Info table. The L_Case_Info table contains 
information about the FEMA case number and includes archived 
electronic data that are relevant to the case. 

SURGE_MDL R E Hurricane Surge Model. This is the name or abbreviation of the 
Federal Emergency Management Agency (FEMA) approved 
hurricane surge model that is associated with the coastal 
engineering analysis. Acceptable values for this field are listed in 
the D_Surge_Mdl table. 

SURGE_DATE R E Hurricane Surge Model Run Date. This is the date the model was 
run. 

SURGE_ZIP R E Filename/path of zip file containing surge model input, surge model 
output, README.TXT, and any other supporting reports and 
documentation. 

SURGE_EFF R E Surge Effective Date. Effective date of the surge model. 

WAVEHT_MDL A E Wave Height Model. This is the name or abbreviation of the 
FEMA approved wave height model that was used for the coastal 
engineering analysis. Acceptable values for this field are listed in 
the the D_Wave_Mdl table. 

WAVEHT_DT A E Wave Height Model Run Date. This is the date the model was run. 


RUNUP_MDL A E Runup Model. This is the name or abbreviation of the FEMA 
approved wave runup model that was used for the coastal 
engineering analysis. Acceptable values for this field are listed in 
the D_Runup_Mdl table. 

RUNUP_DATE A E Runup Model Run Date. This is the date the wave runup model 
was run. 

SETUP_METH A E Wave Setup Methodology. This information should detail the 
methodology used for determining the wave setup magnitude. 

SETUP_DATE A E Wave Setup Methodology Date. This is the date the setup 
methodology was run. 

PFD_TF R E Have primary frontal dune criteria been applied in the coastal 
modeling? Enter "T" for true or "F" for false 

EROS_TF A E Has erosion treatment been applied in the coastal modeling? Enter 
T for true or F for false. 

WAVE_EFF A E Wave Effective Date. Effective date of the wave height and wave 
runup models. 

WAVE_ZIP A E File name/path of zip file containing wave height input, wave 
height output, wave runup input, wave runup output, 
README.TXT, and any other supporting reports and 
documentation. 


Table: L_Cst_Model

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
CST_MDL_ID R E text 11 string 11 character 11 11 character 11 
WTR_NM R E text 100 string 100 character 100 100 character 100 
CASE_NO R E text 50 string 50 character 50 50 character 50 
SURGE_MDL R E text 40 string 40 character 40 40 character 40 
SURGE_DATE R E date/time 8 yyyymmdd 00/00/0000 date date 8 10 date 
SURGE_ZIP R E text 254 string 254 character 254 254 character 254 
SURGE_EFF R E date/time 8 yyyymmdd 00/00/0000 date date 8 10 date 
WAVEHT_MDL A E text 25 string 25 character 25 25 character 25 
WAVEHT_DT A E date/time 8 yyyymmdd 00/00/0000 date date 8 10 date 
RUNUP_MDL A E text 30 string 30 character 30 30 character 30 
RUNUP_DATE A E date/time 8 yyyymmdd 00/00/0000 date date 8 10 date 
SETUP_METH A E text 100 string 100 character 100 100 character 100 
SETUP_DATE A E date/time 8 yyyymmdd 00/00/0000 date date 8 10 date 
PFD_TF R E text 1 string 1 character 1 1 character 1 

L-370


EROS_TF A E text 1 string 1 character 1 1 character 1 
WAVE_EFF A E date/time 8 yyyymmdd 00/00/0000 date date 8 10 date 
WAVE_ZIP A E text 254 string 254 character 254 254 character 254 

L-371


Table: L_Hydra_Model 

This table is only completed if detailed hydraulic engineering methods were used. It is required 
for new studies. 

The L_Hydra_Model table is a lookup table that contains detailed information about the 
hydraulic models used in the engineering analysis for the area. 

There should be one record for each distinct model run. 

This is an Enhanced DFIRM Database table. 

The L_Hydra_Model table contains the following elements. 

HYDRA_ID R S Hydraulic Model Identification. The primary key for table lookup 
that links to the L_XS_Ratings table. The value in this field should 
match the values in the HYDRA_ID field of the L_XS_Ratings 
table. 

HYDRA_MDL R S Hydraulic Model. This is the name or abbreviation of the hydraulic 
model that was used for the engineering analysis. Acceptable 
values for this field are listed in the D_Hydra table. 

HYDRA_DATE R S Hydraulic Model Run Date. This is the date that the hydraulic 
model was run. 

CASE_NO R S FEMA Case Number. This is the FEMA case number for the study. 
This ID may be used to link to the L_Case_Info table. 

HYDRA_ZIP R E Name of the Hydraulic Model Zipfile. This attribute stores the file 
name/pathway of the zipped file that contains the hydraulic model 
input and output data and any other auxiliary hydraulic data 
information. 


Table: L_Hydra_Model

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
HYDRA_ID R E text 11 string 11 character 11 11 character 11 
HYDRA_MDL R E text 40 string 40 character 40 40 character 40 
HYDRA_DATE R E date/time 8 yyyymmdd 00/00/0000 date date 8 10 date 
CASE_NO R E text 12 string 12 character 12 12 character 12 
HYDRA_ZIP R E text 254 string 254 character 254 254 character 254 

L-373


Table: L_Hydro_Model 

This table is required for all studies with new or revised hydrologic data. 

The L_Hydro_Model table contains data specific to a particular hydrologic model used in the 
study. 

This is an Enhanced DFIRM Database table. 

The L_ Hydro_Model table contains the following elements. 

HYDRO_ID R E Hydrologic Model Identification. The primary key for table lookup 
that links to the L_Node_Disch table. 

HYDRO_MDL R E Hydrologic Model. This is the name or abbreviation of the 
hydrologic model that was used for the engineering analysis. 
Acceptable values for this field are listed in the D_Hydro table. 

HYDRO_DATE R E Hydrologic Model Run Date. This is the date that the hydrologic 
model was run. 

CASE_NO R E FEMA Case Number. The case number for the hydrologic model 
links to the L_Case_Info table. 

HYDRO_ZIP R E Name of the Hydrologic Model Zipfile. The file name/pathway of 
the zipped file containing input & output files for hydrologic 
analysis and supporting data analyses. 


Table: L_Hydro_Model

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
HYDRO_ID R E text 11 string 11 character 11 11 character 11 
HYDRO_MDL R E text 40 string 40 character 40 40 character 40 
HYDRO_DATE R E date/time 8 yyyymmdd 00/00/0000 date date 8 10 date 
CASE_NO R E text 12 string 12 character 12 12 character 12 
HYDRO_ZIP R E text 254 string 254 character 254 254 character 254 

L-375


Table: L_Media 

This table is required when digital photographs, sketches, or other media are used to describe 
spatial objects in the study. 

The L_Media table is a lookup table that links archived media to the spatial object represented in 
the photograph, sketch, or other media. 

This is an Enhanced DFIRM Database table. 

The L_Media table contains the following elements. 

MEDIA_ID R E Primary key for table lookup. Assigned by table creator. 

MEDIA_PATH R E The file name/relative path/location of the photograph, sketch, or 
other media. 

OBJ_TABLE R E Object Table. The DFIRM Database table that corresponds to the 
spatial object that the photograph, sketch, or other media describes. 

OBJ_ID R E Object Identification. The DFIRM Database primary key that 
corresponds to the spatial object that the photograph, sketch, or 
other media describes. Can be used as Foreign Key to object. 

MEDIA_TYPE R E Media Type. This is the type of media used to describe the object 
(e.g., Photo, Sketch, Video, etc.) 

MEDIA_DATE R E Media Date. This is the date on which the photograph, sketch, or 
other media was created. 

DSCRIPTION R E Description of the Object. This is a brief description of the object. 
It should include relevant directional information (e.g., Downstream 
face of Third Street bridge, Left bank of Big Creek, Along transect 
21 facing offshore). 

AZIMUTH A E Azimuth of a line that represents the line of sight from where the 
photographer was standing to the object. 0  360 degrees. 


Table: L_Media

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
MEDIA_ID R E text 11 string 11 character 11 11 character 11 
MEDIA_PATH R E text 254 string 254 character 254 254 character 254 
OBJ_TABLE R E text 20 string 20 character 20 20 character 20 
OBJ_ID R E text 11 string 11 character 11 11 character 11 
MEDIA_TYPE R E text 100 string 100 character 100 100 character 100 
MEDIA_DATE R E date/time 8 yyyymmdd 00/00/0000 date date 8 10 date 
DSCRIPTION R E text 254 string 254 character 254 254 character 254 
AZIMUTH A E text 100 string 100 character 100 100 character 100 

L-377


Table: L_MT1_LOMC 

The L_MT1_LOMC table is a lookup table that contains information about Letters of Map 
Change (LOMC) for the area. LOMCs typically include property descriptions. Frequently, 
LOMCs are issued to show that specific locations are outside the Special Flood Hazard Areas. 
Generally, the amount of detail that can be shown on the map does not allow these areas to be 
shown explicitly on the Flood Insurance Rate Map (FIRM). Instead, this information is 
communicated in the form of a LOMC. For data published by the Federal Emergency 
Management Agency (FEMA), this table would only include letters of map amendment and 
letters of map revision based on fill that have been reva lidated following the map revision. 
Revalidated LOMCs indicate that the information presented in the LOMC continues to be true 
regardless of the depiction of this area on the FIRM. 

For LOMCs that appear on more than one map panel, multiple records will exist with the same 
case number, but different panel numbers. 

This is a Standard DFIRM Database table. 

The L_MT1_LOMC table contains the following elements. 

LOMC_ID R S Primary key for table lookup. Assigned by table creator. 

CASE_NO R S Case Number. This is the case number assigned by FEMA to the 
LOMC. This must be filled in for reference back to the complete 
LOMC materials. The case number must be entered without 
hyphens or other separators. 

EFF_DATE R S Effective Date of the LOMC. 

FIRM_PAN R S FIRM panel number that the LOMC is on. This field provides a 
link to the S_FIRM_Pan table. MT1 LOMCs can be matched to a 
specific FIRM panel by matching this field to the FIRM_PAN field 
of the S_FIRM_Pan table. 

LOMC_STAT R S Status of the LOMC. Valid entries for this field include the 
following: 

superseded 
revalidated 

incorporated 

redetermined 

Only revalidated LOMCs are still in effect after a panel has been 
revised. All others must be superseded, redetermined or 


incorporated into the new FIRM. Therefore, a final DFIRM 
Database will only include revalidated LOMCs. 


Table: L_MT1_LOMC

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
LOMC_ID R S text 11 string 11 character 11 11 character 11 
CASE_NO R S text 13 string 13 character 13 13 character 13 
EFF_DATE R S date/time 8 yyyymmdd 00/00/0000 date date 8 10 date 
FIRM_PAN R S text 11 string 11 character 11 11 character 11 
LOMC_STAT R S text 20 string 20 character 20 20 character 20 

L-380


Table: L_Node_Disch 

This table is required when hydrologic routing (flow combining) is used in the hydrologic 
analysis. For nodes whose subbasins are headwaters, this table will contain the same flow 
information as the subbasins outflow table.

L_Node_Disch is a lookup table that contains information regarding hydrologic routing.
A node may have none, one, or many links connected to it.
If an existing node is to be moved, it must be renamed.

This is an Enhanced DFIRM Database table.
The L_Node_Disch table contains the following elements.

FLOW_ID R E Primary key for this table. Assigned by table creator.

NODE_ID R E Node Identification. A code that links to the S_Nodes table.

NODE_TYPE R E Node Type. Values include junction (default), reservoir, structure, 
and diversion. A junction node may have none, one, or many links 
connected to it. Acceptable values for this field are listed in the 
D_Nodes table. 

HYDRO_ID R E Hydrologic Model Identification. Link to the L_Hydro_Model 
table, which stores information about the hydrologic methods used 
in the study. 

FREQUENCY R E Frequency Interval. This attribute stores the return period for the 
associated discharge. Acceptable values for this field are listed in 
the D_Frequency table. 

DISCHARGE R E Discharge. Subbasin discharge/outflow for the above return period. 

DISCH_UNIT R E Discharge Unit. This attribute stores the unit for the discharge. 
Acceptable values for this field are listed in the D_Discharge_Units 
table. 


Table: L_Node_Disch

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
FLOW_ID R E text 11 string 11 character 11 11 character 11 
NODE_ID R E text 11 string 11 character 11 11 character 11 
NODE_TYPE R E text 10 string 10 character 10 10 character 10 
HYDRO_ID R E text 11 string 11 character 11 11 character 11 
FREQUENCY R E text 100 string 100 character 100 100 character 100 
DISCHARGE R E text 11 string 11 character 11 11 character 11 
DISCH_UNIT R E text 20 string 20 character 20 20 character 20 

L-382


Table: L_Pan_Revis 

This table will not apply for an initial Flood Insurance Rate Map (FIRM) or for a FIRM that has 
a completely new paneling scheme such as a first time countywide FIRM. Otherwise, this table 
is required for all Preliminary or Final Digital Flood Insurance Rate Map databases. 

The L_Pan_Revis table is a lookup table that contains information about historic revisions to 
each FIRM panel. 

For each FIRM panel that is being revised, there must be at least one record. There may also be 
multiple records for multiple revision dates for a particular panel and there may be multiple 
records for a single revision date if there are multiple revision notes for that date. Each FIRM 
panel may have a unique set of revision dates and revision codes. There must be one record for 
each FIRM_PAN, REVIS_DATE, REVIS_NOTE combination. 

This is a Standard DFIRM Database table. 

The L_Pan_Revis table contains the following elements. 

REVIS_ID R S Primary key for table lookup. Assigned by table creator. 

FIRM_PAN R S FIRM Panel Number. This field links to the S_FIRM_Pan table. 
This must match a value in the FIRM_PAN field of the 
S_FIRM_Pan table. This is the complete FIRM panel number, 
which is made up of ST_FIPS, PCOMM, PANEL, and SUFFIX, 
which are found in S_FIRM_Pan table. The FIRM panel number is 
the 11-digit FIRM panel number that is shown in the title block of 
the map. 

REVIS_DATE R S Revision Date. Effective date of revision to the FIRM panel. 
FIRM revision dates can be found in the FIRM legend or the Flood 
Insurance Study (FIS) report. 

REVIS_NOTE R S Revision Note. Note describing the reason for the revision to the 
panel. This is shown under the effective date in the FIRM legend 
or in the FIS report. A list of standard revision notes appears in 
Appendix K of these Guidelines. 


Table: L_Pan_Revis

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
REVIS_ID R S text 11 string 11 character 11 11 character 11 
FIRM_PAN R S text 11 string 11 character 11 11 character 11 
REVIS_DATE R S date/time 8 yyyymmdd 00/00/0000 date date 8 10 date 
REVIS_NOTE R S text 254 string 254 character 254 254 character 254 

L-384


Table: L_Pol_FHBM 

This table will not apply if all communities on the Flood Insurance Rate Map (FIRM) never had 
revisions to their Flood Hazard Boundary Maps (FHBMs). Otherwise, this table is required for 
all Digital Flood Insurance Rate Map databases. 

The L_Pol_FHBM table is a lookup table that contains a list of communities and FHBM 
revisions. 

Each community may have different revision dates. Each revision date may have multiple 
revision notes. 

This is a Standard DFIRM Database table. 

The L_Pol_FHBM table contains the following elements. 

FHBM_ID R S Primary key for table lookup. Assigned by table creator. 

CID R S Community Identification Number, which links to the S_Pol_Ar 
table. The value in this field must match a value in the CID field of 
the S_Pol_Ar table. This is the six-digit community identification 
number assigned by the Federal Emergency Management Agency 
(FEMA). It is created by combining the state Federal Information 
Processing Standard code with the COMM_NO. Only communities 
which have had a revision to their FHBM will appear in this table. 

FHBM_DATE R S FHBM revision date. 

FHBM_NOTE R S FHBM revision note that describes the reason for the revision. 
FHBM revision notes are shown in the FIRM legend or Flood 
Insurance Study report. A list of standard revision notes appears in 
Appendix K of these Guidelines. 


Table: L_Pol_FHBM

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
FHBM_ID R S text 11 string 11 character 11 11 character 11 
CID R S text 6 string 6 character 6 6 character 6 
FHBM_DATE R S date/time 8 yyyymmdd 00/00/0000 date date 8 10 date 
FHBM_NOTE R S text 254 string 254 character 254 254 character 254 

L-386


Table: L_Regression 

This table is required when regression equations are used in hydrologic analysis. 

L_Regression is a lookup table that stores information regarding the regression equations utilized 
in the hydrologic modeling. 

This is an Enhanced DFIRM Database table. 

The L_Regression table contains the following elements. 

REGR_ID R E Primary key for this table. Assigned by table creator. 

SUBBAS_ID R E Subbasin Identification. A code that provides a link to a valid entry 
from the S_Subbasins table. 

REGR_EQN R E Regression Equation. Regression equation used in the analysis. 
Non-Roman symbols (e.g., Greek) should be spelled out (e.g., Phi). 

REGR_RPT R E Regression Report. This field stores the name of the report in 
which the regression equation was published. 


Table: L_Regression

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
Type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
REGR_ID R E text 11 string 11 character 11 11 character 11 
SUBBAS_ID R E text 11 string 11 character 11 11 character 11 
REGR_EQN R E text 254 string 254 character 254 254 character 254 
REGR_RPT R E text 254 string 254 character 254 254 character 254 

L-388


Table: L_Stn_Start 

This table is required for any Digital Flood Insurance Rate Map database that has an S_XS or 
S_Riv_Mrk table. Because of production limitations, it may be omitted at the direction of the 
FEMA Project Officer. 

The L_Stn_Start table contains information about station starting locations. These locations 
indicate the reference point that was used as the origin for distance measurements along streams 
and rivers. This table is referenced by both the S_XS table, which contains stream station 
information for cross section, and by the S_Riv_Mrk table, which contains river distance marker 
points. The location of the stationing start for a group of cross sections is normally referenced as 
a note on the Floodway Data table and on the Flood Profiles. Generally, all of the cross sections 
for a particular reach are referenced to the same starting point. If multiple reaches are measured 
from the same point, they may share the same record in L_Stn_Start. 

This is a Standard DFIRM Database table. 

The L_Stn_Start table contains the following elements. 

START_ID R S Primary key for table lookup. Assigned by table creator. This field 
is the link that is used to reference cross section in the S_XS table 
or river marks in the S_Riv_Mrk table to the appropriate stationing 
starting point. 

START_DESC R S Start Description. The description of the location of the station 
starting point. This should include the measurement units. For 
example, Distances are measured in feet upstream from the 
confluence with the Main Channel of the Big River. 


Table: L_Stn_Start

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
START_ID R S text 11 string 11 character 11 11 character 11 
START_DESC R S text 254 string 254 character 254 254 character 254 

L-390


Table: L_Storm_Curve 

This table is required when precipitation data are used in the hydrologic analysis. 

The L_Storm_Curve table accommodates descriptions of Depth-Duration-Frequency (DDF) and 
Intensity-Duration-Frequency (IDF) relationships, as well as durations of e.g. design storms and 
precipitation patterns of historical storms. 

This is an Enhanced DFIRM Database table. 

The L_Storm_Curve table contains the following elements. 

CURVE_ID R E Primary key for this table. Assigned by table creator. 

STORM_ID R E Storm Identification. A code that provides a link to a valid entry 
from the L_Storm_Info table. 

DURATION R E Duration. Duration of precipitation event. The duration is that of a 
design or historical storm, or of a point on a DDF or IDF curve. 

TIME_UNIT R E Duration Unit. This attribute establishes the unit of measure of the 
corresponding duration entry. Acceptable values for this field are 
listed in the D_Time_Units table. 

DEPTH A E Precipitation Depth. This field is populated only if entering data for 
a DDF curve. 

LEN_UNIT A E Precipitation Depth Unit. This attribute establishes the unit of 
measure for precipitation depth. This field is populated only if a 
precipitation depth is entered. Acceptable values for this field are 
listed in the D_Length_Units table. 

INTENSITY A E Rainfall Intensity. This field is populated only if entering data for 
an IDF curve. 

VEL_UNIT A E Rainfall Intensity Unit. This attribute establishes the unit of 
measure for precipitation intensity. This field is populated only if a 
precipitation intensity is entered. Acceptable values for this field 
are listed in the D_Velocity_Units table. 

FREQUENCY A E Frequency Interval. This attribute stores the return period of the 
associated discharge. Acceptable values for this field are listed in 
the D_Frequency table. 


Table: L_Storm_Curve

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
Type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
CURVE_ID R E text 11 string 11 character 11 11 character 11 
STORM_ID R E text 11 string 11 character 11 11 character 11 
DURATION R E text 11 string 11 character 11 11 character 11 
TIME_UNIT R E text 20 string 20 character 20 20 character 20 
DEPTH A E 
number 
(double) 8 2 number 13 2 numeric 8 13 2 decimal 15 2 
LEN_UNIT A E text 20 string 20 character 20 20 character 20 
INTENSITY A E 
number 
(double) 8 2 number 13 2 numeric 8 13 2 decimal 15 2 
VEL_UNIT A E text 20 string 20 character 20 20 character 20 
FREQUENCY A E text 100 string 100 character 100 100 character 100 

L-392


Table: L_Storm_Info 

This table is required when precipitation distributions are used in the hydrologic analysis. 

The L_Storm_Info table is a lookup table that contains basic descriptions of precipitation 
patterns. 

This is an Enhanced DFIRM Database table. 

The L_Storm_Info table contains the following elements. 

STORM_ID R E Primary key for this table. Assigned by table creator. 

STORM_TYPE R E Storm Type. This attribute establishes the storm type. Acceptable 
values for this field are listed in the D_Storms table. 

STORM_DESC A E Storm Description. Brief text description/note for the storm. 

SUBBAS_ID R E Subbasin Identification. A code that provides a link to a valid entry 
from the S_Subbasins table. 


Table: L_Storm_Info

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
STORM_ID R E text 11 string 11 character 11 11 character 11 
STORM_TYPE R E text 20 string 20 character 20 20 character 20 
STORM_DESC A E text 254 string 254 character 254 254 character 254 
SUBBAS_ID R E text 11 string 11 character 11 11 character 11 

L-394


Table: L_Subbas_Disch 

This table is required for all studies with new or revised non-coastal hydrologic data. 

The L_Subbas_Disch table is a lookup table that contains outflow data for each subbasin and 
recurrence interval in the hydrologic analysis. The subbasin outflow data is specific to that 
subbasin and must not be a cumulative system flow. (System flows, if required, are assigned in 
L_Node_Disch.) 

This is an Enhanced DFIRM Database table. 

The L_ Subbas_Disch table contains the following elements.
DISCH_ID R E Primary key for this table. Assigned by table creator.

SUBBAS_ID R E Subbasin Identification. A code that provides a link to a valid entry 
from the S_Subbasins table. 

FREQUENCY R E Frequency Interval. This attribute stores the return period for the 
associated discharge. Acceptable values for this field are listed in 
the D_Frequency table. 

DISCHARGE R E Discharge. Subbasin discharge/outflow for the above return period. 

DISCH_UNIT R E Discharge Unit. This attribute stores the discharge unit value. 
Acceptable values for this field are listed in the D_Discharge_Units 
table. 


Table: L_Subbas_Disch

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
DISCH_ID R E text 11 string 11 character 11 11 character 11 
SUBBAS_ID R E text 11 string 11 character 11 11 character 11 
FREQUENCY R E text 100 string 100 character 100 100 character 100 
DISCHARGE R E 
number 
(double) 8 2 number 13 2 numeric 8 13 2 decimal 15 2 
DISCH_UNIT R E text 20 string 20 character 20 20 character 20 

L-396


Table: L_XS_Ratings 

This table is required for a detailed study. 

The L_XS_Ratings table is a lookup table that contains information about the cross sections. 
This table should contain a record for each frequency / scenario associated with a cross section. 
For instance, if a cross section has data for the 25-, 100-and 500-year recurrence intervals, the 
L_XS_Ratings table should have three associated records. Therefore, each cross section should 
be associated with at least one record in L_XS_Ratings. The L_XS_Ratings table should possess 
at least one record at all times: the data for the 100-year regulatory model. 

This is an Enhanced DFIRM Database table. 

The L_XS_Ratings table contains the following elements. 

XS_RATG_ID R E Primary key for table lookup. Assigned systematically by the 
creator. 

XS_LN_ID R E Foreign key for table lookup that links to the S_XS table. Value in 
this field should match the values in the XS_LN_ID field of the 
S_XS table. 

XS_NO R E Cross Section Number. This attribute is used for all cross sections 
that are created during the engineering analysis. This must be 
populated with the number associated with the cross section used by 
the Mapping Partner in their modeling of the stream. 

REACH_NM A E Reach Name. This attribute stores that name of the reach in the 
model that the cross section intersects. XS_NO and REACH_NM 
may be used in conjunction as a unique identifier to identify the 
correct cross section in the model zipfile. This field is not 
populated if the correct cross section may be identified in the model 
without merging XS_NO and REACH_NM. 

FREQUENCY R E Frequency Interval. This field identifies the hydraulic analysis that 
applies to this record. Hydraulic analysis can be a recurrence 
interval (e.g., 1 percent or 0.2 percent flood hazard) or a scenario, 
for example without levee or with floodway. Acceptable values for 
this field are listed in the D_Frequency table. D_Frequency is an 
existing domain table that may be added to by the Mapping Partner 
that creates the database. 

FREQ_WSEL R E Water Surface Elevation. This is the water surface elevation 
associated with the frequency or scenario identified in 
FREQUENCY. 


LEN_UNIT R E Length Unit. This unit indicates the measurement system used 
for the water surface elevation, stream bed elevation, and top width. 
Acceptable values for this field are listed in the D_Length_Units 
table. 

V_DATUM R E Vertical Datum. The vertical datum indicates the reference surface 
from which the flood elevations are measured. Normally this would 
be North American Vertical Datum of 1988 for new studies. 
Acceptable values for this field are listed in the D_V_Datum table. 

FREQ_Q A E Discharge Value. This is the discharge value associated with the 
frequency or scenario identified in FREQUENCY. This field is 
required when the frequency or scenario identified is based on a 
discharge value. For example, it is not required for stage gage 
analysis on rivers near the coast. 

DISCH_UNIT A E Discharge Unit. This unit specifies the unit of measurement for the 
discharge. This field is populated only if a discharge value is 
entered. Acceptable values for this field are listed in the 
D_Discharge_Units table. 

HYDRA_ID R E Hydraulic Model Identification. A code that provides a link to the 
hydraulic model table, L_Hydra_Model. The L_Hydra_Model 
table will identify the hydraulic model used to calculate the flood 
hazard at this cross section line. This ID field must contain a 
number that matches the HYDRA_ID field for a record in the 
L_Hydra_Model table. The L_Hydra_Model table documents 
model information for this cross section. Multiple cross sections 
may link to a single record in the L_Hydra_Model table. 

HYDRO_ID R E Hydrologic Model Identification. A code that provides a link to the 
hydrologic model table, L_Hydro_Model. The L_Hydro Model 
table will identify the hydrologic model used to calculate the flood 
hazard at this cross section line. This ID field for a record in the 
L_Hydro_Model table. The L_Hydro_Model table documents 
model information for this cross section. Multiple cross sections 
may link to a single record in the L_Hydro_Model table. 

EFF_MODELS R E Effective Hydraulic and Hydrologic Model. This field is true only 
if the elevation and discharge are the result of the effective 
hydraulic and hydrologic models at this cross section. Enter T 
for true or F for false. 


Table: L_XS_Ratings

Field R/A S/E MS Access ESRI Shapefile ESRI Coverage MapInfo 
type 
field 
size dec format input mask type width dec type 
item 
width 
output 
width dec type width dec 
XS_RATG_ID R E text 11 string 11 character 11 11 character 11 
XS_LN_ID R E text 11 string 11 character 11 11 character 11 
XS_NO R E text 12 string 12 character 12 12 character 12 
REACH_NM A E text 254 string 100 character 100 100 character 100 
FREQUENCY R E text 100 string 254 character 254 254 character 254 
FREQ_WSEL R E 
number 
(double) 8 2 number 8 2 numeric 8 13 2 decimal 15 2 
LEN_UNIT R E text 20 string 20 character 20 20 character 20 
V_DATUM R E text 6 string 6 character 6 6 character 6 
FREQ_Q A E 
number 
(double) 8 2 number 8 2 numeric 8 13 2 decimal 15 2 
DISCH_UNIT A E text 20 string 20 character 20 20 character 20 
HYDRA_ID R E text 11 string 11 character 11 11 character 11 
HYDRO_ID R E text 11 string 11 character 11 11 character 11 

L-399


EFF_MODELS R E text 1 string 1 character 1 1 character 1 

L-400


L.8 Metadata Example for Preliminary and Final Digital 
Flood Insurance Rate Map Databases 

DFIRM DATABASE, FLOOD COUNTY, USA 

Identification_Information: 
Citation: 
Citation_Information: 
Originator: Federal Emergency Management Agency 
Publication_Date: 20000505 
Title: DIGITAL FLOOD INSURANCE RATE MAP DATABASE, FLOOD COUNTY, USA 

Geospatial_Data_Presentation_Form: Vector and Raster Digital Data 
Publication_Information: 
Publication_Place: Washington, DC 
Publisher: Federal Emergency Management Agency 

Other_Citation_Details: Metadata_File_Name: 99009C_19980915_metadata.htm 
Online_Linkage: http://www.fema.gov/msc 
Description: 

Abstract: The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information 
and supporting data used to develop the risk data. The primary risk classifications used are the 1-
percent-annual-chance flood event, the 0.2-percent-annual-chance flood event, and areas of minimal 
flood risk. The DFIRM Database is derived from Flood Insurance Studies (FISs), previously 
published Flood Insurance Rate Maps (FIRMs), flood hazard analyses performed in support of the 
FISs and FIRMs, and new mapping data, where available. The FISs and FIRMs are published by the 
Federal Emergency Management Agency (FEMA). The file is georeferenced to earth's surface using 
the UTM projection and coordinate system. The specifications for the horizontal control of DFIRM 
data files are consistent with those required for mapping at a scale of 1:12,000. 

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 Flood Disaster Protection Act of 1973. 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 coverage offered through the NFIP. 

The DFIRM Database presents the flood risk information depicted on the FIRM in a digital format 
suitable for use in electronic mapping applications. The DFIRM database is a subset of the Digital 
FIS database that serves to archive the information collected during the FIS. 

Time_Period_of_Content: 
Time_Period_Information: 
Single_Date/Time: 

Calendar_Date: 19980701 

Currentness_Reference: FIRM and FIS effective date 

Status: 
Progress: Complete 
Maintenance_and_Update_Frequency: Irregular 

Spatial_Domain: 
Bounding_Coordinates: 

West_Bounding_Coordinate: -84.125 
East_Bounding_Coordinate: -84.25 
North_Bounding_Coordinate: 30.5 
South_Bounding_Coordinate: 30.625 


Keywords: 

Theme: 
Theme_Keyword_Thesaurus: None 
Theme_Keyword: FEMA Flood Hazard Zone 
Theme_Keyword: DFIRM Database 
Theme_Keyword: DFIRM 
Theme_Keyword: Special Flood Hazard Area 
Theme_Keyword: Digital Flood Insurance Rate Map 
Theme_Keyword: CBRS 
Theme_Keyword: Coastal Barrier Resources System 
Theme_Keyword: Riverine Flooding 
Theme_Keyword: Coastal Flooding 
Theme_Keyword: NFIP 
Theme_Keyword: Base Flood Elevation 
Theme_Keyword: SFHA 
Theme_Keyword: Flood Insurance Rate Map 
Theme_Keyword: FIRM 
Theme_Keyword: Floodway 

Place: 
Place_Keyword_Thesaurus: None 

Place_Keyword: FLOOD COUNTY 
Place_Keyword: USA 

Access_Constraints: None 

Use_Constraints: The hardcopy FIRM and DFIRM and the accompanying FISs are the official 
designation of SFHAs and Base Flood Elevations (BFEs) for the NFIP. For the purposes of the NFIP, 
changes to the flood risk information published by FEMA may only be performed by FEMA and 
through the mechanisms established in the NFIP regulations (44 CFR Parts 59-78). 

These digital data are produced in conjunction with the hardcopy FIRMs and generally match the 
hardcopy map exactly. However the hardcopy flood maps and flood profiles are the authoritative 
documents for the NFIP. 

Acknowledgement of FEMA would be appreciated in products derived from these data. 

Point_of_Contact: 
Contact_Information: 
Contact_Organization_Primary: 

Contact_Organization: Federal Emergency Management Agency 
Contact_Position: Federal Insurance and Mitigation Administration 
Contact_Address: 

Address_Type: mailing address
Address: 500 C Street, S.W.
City: Washington
State_or_Province: District of Columbia
Postal_Code: 20472
Country: USA

Contact_Voice_Telephone: 1-800-358-9616 
Contact_Electronic_Mail_Address: www.fema.gov/msc 
Native_Data_Set_Environment: Original data development environment varies. Finishing of the data is 
done using ESRIs ARC/INFO software. 
Cross_Reference: 
Citation_Information: 
Originator: Federal Emergency Management Agency 

Publication_Date: 19980701
Title: Flood Insurance Rate Map, FLOOD COUNTY, USA

Geospatial_Data_Presentation_Form: map 
Publication_Information: 


Publication_Place: Washington, DC 
Publisher: Federal Emergency Management Agency 
Cross_Reference: 
Citation_Information: 
Originator: Federal Emergency Management Agency 

Publication_Date: 19980701
Title: Flood Insurance Study, FLOOD COUNTY, USA

Geospatial_Data_Presentation_Form: document 

Publication_Information: 
Publication_Place: Washington, DC 
Publisher: Federal Emergency Management Agency 

Cross_Reference: 

Citation_Information: 
Originator: Federal Emergency Management Agency 
Publication_Date: 19980701 
Title: Raster DFIRM, FLOOD COUNTY, USA 
Geospatial_Data_Presentation_Form: raster digital data 
Publication_Information: 

Publication_Place: Washington, DC 
Publisher: Federal Emergency Management Agency 
Data_Quality_Information: 
Attribute_Accuracy: 

Attribute_Accuracy_Report: The DFIRM Database consists of countywide vector files and 
associated attributes produced in conjunction with the hard copy FEMAFIRM. The published 
effective FIRM and DFIRM maps are issued as the official designation of the SFHAs. As such they 
are adopted by local communities and form the basis for administration of the NFIP. For these 
purposes they are authoritative. Provisions exist in the regulations for public review, appeals and 
corrections of the flood risk information shown to better match real world conditions. As with any 
engineering analysis of this type, variation from the estimated flood heights and floodplain 
boundaries is possible. Details of FEMA's requirements for the FISs and flood mapping process that 
produces these data are available in the Guidelines and Specifications for Flood Hazard Mapping 
Partners. Attribute accuracy was tested by manual comparison of source graphics with hardcopy 
plots and a symbolized display on an interactive computer graphic system. 

Independent quality control testing of FEMAs DFIRM database was also performed. 

To obtain more detailed information in areas where Base Flood Elevations (BFEs) and/or 
floodways have been determined, users are encouraged to consult the Flood Profiles and Floodway 
Data and/or Summary of Stillwater Elevations tables contained within the FIS report that 
accompanies this DFIRM database. Users should be aware that BFEs shown in the S_BFE table 
represent rounded whole-foot elevations. These BFEs are intended for flood insurance rating 
purposes only and should not be used as the sole source of flood elevation information. 
Accordingly, flood elevation data presented in the FIS report must be used in conjunction with the 
FIRM for purposes of construction and/or floodplain management. The 1-percent-annual-chance 
water-surface elevations shown in the S_XS table match the regulatory elevations shown in the FIS 
report. 

Logical_Consistency_Report: When FEMA revises an FIS, adjacent studies are checked to ensure 
agreement between flood elevations at the boundaries. Likewise flood elevations at the confluence of 
streams studied independently are checked to ensure agreement at the confluence. The FIRM and the 
FIS are developed together and care is taken to ensure that the elevations and other features shown on 
the flood profiles in the FIS agree with the information shown on the FIRM. However, the elevations as 
shown on the FIRM are rounded whole-foot elevations. They must be shown so that a profile recreated 
from the elevations on the FIRM will match the FIS profiles within one half of one foot. 

Completeness_Report: Data contained in the DFIRM Database files reflect the content of the source 
materials. Features may have been eliminated or generalized on the source graphic, due to scale and 
legibility constraints. With new mapping, FEMA plans to maintain full detail in the spatial data it 


produces. However, older information is often transferred from existing maps where some 
generalization has taken place. 

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 analyses of records of 
river flow, storm tides, and rainfall; information obtained through consultation with the communities; 
floodplain topographic surveys; and hydrological 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 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. 

Positional_Accuracy: 
Horizontal_Positional_Accuracy: 
Horizontal_Positional_Accuracy_Report: The DFIRM Database consists of countywide vector 
files and associated attributes produced in conjunction with the hardcopy FEMA FIRM. The 
published effective FIRM and DFIRM are issued as the official designation of the SFHAs. As 
such they are adopted by local communities and form the basis for administration of the NFIP. 
For these purposes they are authoritative. Provisions exist in the regulations for public review, 
appeals and corrections of the flood risk information shown to better match real world 
conditions. As with any engineering analysis of this type, variation from the estimated flood 
heights and floodplain boundaries is possible. Details of FEMA's requirements for the FISs and 
flood mapping process that produces these data are available in the Guidelines and 
Specifications for Flood Hazard Mapping Partners. Horizontal accuracy was tested by manual 
comparison of source graphics with hardcopy plots and a symbolized display on an interactive 
computer graphic system. 

Independent quality control testing of FEMAs DFIRM database was also performed. 

Vertical_Positional_Accuracy: 
Vertical_Positional_Accuracy_Report: The DFIRM Database consists of countywide vector 
files and associated attributes produced in conjunction with the hardcopy FEMA FIRM. The 
published effective FIRM and DFIRM maps are issued as the official designation of the 
SFHAs. As such they are adopted by local communities and form the basis for administration 
of the NFIP. For these purposes they are authoritative. Provisions exist in the regulations for 
public review, appeals and corrections of the flood risk information shown to better match real 
world conditions. As with any engineering analysis of this type, variation from the estimated 
flood heights and floodplain boundaries is possible. Details of FEMA's require ments for the 
FISs and flood mapping process that produces these data are available in the Guidelines and 
Specifications for Flood Hazard Mapping Partners. Vertical accuracy was tested by manual 
comparison of source graphics with hardcopy plots and a symb olized display on an interactive 
computer graphic system. 

Independent quality control testing of FEMAs DFIRM database was also performed. 
Lineage 
Source_Information: 
Source_Citation: 

Citation_Information: 
Originator: Federal Emergency Management Agency 
Publication_Date: 1987 
Title: Flood Insurance Study, FLOOD COUNTY USA (Unincorporated areas). 
Geospatial_Data_Presentation_Form: map 
Publication_Information: 

Publication_Place: Washington, DC
Publisher: Federal Emergency Management Agency

Other_Citation_Details: The hydrologic and hydraulic analyses for the FIS dated April 
17, 1987, were prepared by the U.S. Army Corps of Engineers (USACE), Springfield 
District, for the Federal Emergency Management Agency (FEMA), under Inter-


Agency Agreement No. EMW-84-E-1506. That work was completed in December 

1985. Denominator_of_Source_Scale: 2400-12000. 
Source_Scale_Denominator: 12,000 
Type_of_Source_Media: paper 
Source_Time_Period_of_Content: 

Time_Period_Information: 
Single_Date/Time: 

Calendar_Date: 19870601 

Source_Currentness_Reference: Effective Date 

Source_Citation_Abbreviation: FIS1 

Source_Contribution: Spatial and attribute information, floodplain widths, BFEs, floodplain 
location. 
Source_Information: 
Source_Citation: 
Citation_Information: 
Originator: Federal Emergency Management Agency 

Publication_Date: 1987
Title: Flood Insurance Study, FLOODVILLE, Town of

Geospatial_Data_Presentation_Form: map 

Publication_Information: 
Publication_Place: Washington, DC 
Publisher: Federal Emergency Management Agency 

Other_Citation_Details: The hydrologic and hydraulic analyses for the FIS report dated 
April 17, 1987, were prepared by the USACE, Springfield District, for the FEMA, 
under Inter-Agency Agreement No. EMW-84-E-1506, Project Order No. 1, 
Amendment No. 4. That work was completed in December 1985. 
Denominator_of_Source_Scale: 2400-12000. 

Source_Scale_Denominator: 12,000 
Type_of_Source_Media: paper 
Source_Time_Period_of_Content: 

Time_Period_Information: 
Single_Date/Time: 

Calendar_Date: 19870601 

Source_Currentness_Reference: Effective Date 

Source_Citation_Abbreviation: FIS2 

Source_Contribution: Spatial and attribute information, floodplain widths, BFEs, floodplain 
location. 
Source_Information: 
Source_Citation: 

Citation_Information: 
Originator: Federal Emergency Management Agency 
Publication_Date: 1998 
Title: Flood Insurance Study Report, FLOOD COUNTY, USA and Incorporated areas. 
Geospatial_Data_Presentation_Form: map 
Publication_Information: 

Publication_Place: Washington, DC
Publisher: Federal Emergency Management Agency

Other_Citation_Details: For this countywide FIS, the hydrologic and hydraulic analyses 
were prepared by USACE for FEMA, under Inter-Agency Agreement No. EMW-94-
C-0019. This work was completed in October 1995. Denominator_of_Source_Scale: 
2400-12000. 

Source_Scale_Denominator: 12000 
Type_of_Source_Media: paper 
Source_Time_Period_of_Content: 

Time_Period_Information: 
Single_Date/Time: 


Calendar_Date: 19980701 

Source_Currentness_Reference: Effective Date 

Source_Citation_Abbreviation: FIS3 

Source_Contribution: Spatial and attribute information, floodplain widths, BFEs, floodplain 
location. 
Source_Information: 
Source_Citation: 
Citation_Information: 
Originator: Town of Floodville Stormwater Management Department, 126 Royal Oaks 

Drive, Suite 201, Floodville, USA 99150 
Publication_Date: 1995 
Title: Base map for Floodville, USA 
Geospatial_Data_Presentation_Form: vector digital data 
Publication_Information: 

Publication_Place: Floodville, USA 
Publisher: Town of Floodville Stormwater Management 
Other_Citation_Details: These files were photogrammetrically compiled at scales of 

1"=200' (urban areas) and 1"=400' (rural areas) from aerial photographs. 
Source_Scale_Denominator: 4,800 
Type_of_Source_Media: CD-ROM 
Source_Time_Period_of_Content: 

Time_Period_Information: 
Single_Date/Time: 
Calendar_Date: 19950301 

Source_Currentness_Reference: ground conditions 
Source_Citation_Abbreviation: BASE1 
Source_Contribution: Location of roads, railroads, bridges, streams and other physical features 

shown. 

Source_Information: 
Source_Citation: 
Citation_Information: 
Originator: Flood County Geographic Information Systems Department, 1110 South 

Road, Suite 205, Floodville, USA 99150 
Publication_Date: 1995 
Title: Base map for Flood County, USA 
Geospatial_Data_Presentation_Form: vector digital data 
Publication_Information: 

Publication_Place: Floodville, USA 
Publisher: Flood County Geographic Information Systems Department 
Other_Citation_Details: These files were photogrammetrically compiled at scales of 

1"=200' (urban areas) and 1"=400' (rural areas) from aerial photographs. 
Source_Scale_Denominator: 4,800 
Type_of_Source_Media: CD-ROM 
Source_Time_Period_of_Content: 

Time_Period_Information: 
Single_Date/Time: 
Calendar_Date: 19950301 

Source_Currentness_Reference: ground conditions 
Source_Citation_Abbreviation: BASE2 
Source_Contribution: Location of roads, railroads, bridges, streams and other physical features 

shown: 
Source_Information: 
Source_Citation: 

Citation_Information: 
Originator: U.S. Geological Survey 
Publication_Date: 1998 


Title: Digital Orthophoto Quadrangle 
Geospatial_Data_Presentation_Form: remote-sensing image 
Publication_Information: 

Publication_Place: Reston, VA 
Publisher: U.S. Geological Survey 

Other_Citation_Details: The digital orthophoto quadrangle (DOQ) is a 1-meter ground 
resolution, quarter-quadrangle (3.75-minutes of latitude by 3.75-minutes of longitude) 
image cast on the Universal Transverse Mercator Projection (UTM) on the North 
American Datum of 1983 (NAD83). The imagery is based on panchromatic black 
and white (or color infra-red) NAPP or NAPP-like photography. 

Source_Scale_Denominator: 12,000 
Type_of_Source_Media: CD-ROM 
Source_Time_Period_of_Content: 

Time_Period_Information: 
Single_Date/Time: 
Calendar_Date: 19970301 

Source_Currentness_Reference: ground conditions 
Source_Citation_Abbreviation: BASE3 
Source_Contribution: Location of roads, railroads, bridges, streams and other physical features 

shown: 

Process_Step: 

Process_Description: The DFIRM Database is compiled in conjunction with the hardcopy FIRM 
and the final FIS report. The specifics of the hydrologic and hydraulic analyses performed are 
detailed in the FIS report. The results of these studies are submitted in digital format to FEMA. 
These data and unrevised data from effective FIRMs are compiled onto the base map used for 
DFIRM publication and checked for accuracy and compliance with FEMA standards. 

Source_Used_Citation_Abbreviation: FIS1-FIS3, BASE1-BASE3 
Process_Date: 1996 
Spatial_Data_Organization_Information: 
Direct_Spatial_Reference_Method: Vector and raster 
Point_and_Vector_Object_Information: 
SDTS_Terms_Description: 
SDTS_Point_and_Vector_Object_Type: Point 
SDTS_Terms_Description: 
SDTS_Point_and_Vector_Object_Type: String 
SDTS_Terms_Description: 
SDTS_Point_and_Vector_Object_Type: GT -polygon composed of chains 
Raster_Object_Information: 
Raster_Object_Type: Pixel 
Spatial_Reference_Information: 
Horizontal_Coordinate_System_Definition: 
Planar: 
Grid_Coordinate_System: 

Grid_Coordinate_System_Name: Universal Transverse Mercator 

Universal_Transverse_Mercator: 
UTM_Zone_Number: 16 
Transverse_Mercator: 

Scale_Factor_at_Central_Meridian: 0.9996
Longitude_of_Central_Meridian: -87.0
Latitude_of_Projection_Origin: 0.0
False_Easting: 500000
False_Northing: 0.0

Planar_Coordinate_Information: 
Planar_Coordinate_Encoding_Method: Coordinate Pair 
Coordinate_Representation: 

Abscissa_Resolution: 0.061 


Ordinate_Resolution: 0.061 
Planar_Distance_Units: meters 
Geodetic_Model: 

Horizontal_Datum_Name: North American Datum 1983 
Ellipsoid_Name: Geodetic Reference System 80 
Semi-major_Axis: 6378206.4 
Denominator_of_Flattening_Ratio: 294.98 

Vertical_Coordinate_System_Definition: 
Altitude_System_Definition: 

Altitude_Datum_Name: North American Vertical Datum of 1988
Altitude_Resolution: 0.03
Altitude_Distance_Units: feet

Altitude_Encoding_Method: Attribute Values 
Entity_and_Attribute_Information: 
Overview_Description: 

Entity_and_Attribute_Overview: The DFIRM Database is made up of several data themes containing 
both spatial and attribute information. These data together represent the current flood risk for the 
subject area as identified by FEMA. The attribute tables include SFHA locations, flood zone 
designations, BFEs, political entities, cross-section locations, FIRM panel information, and other 
data related to the NFIP. 

Entity_and_Attribute_Detail_Citation: Appendix L of FEMAs Guidelines and Specifications for 
FEMA Flood Hazard Mapping Partners contains a detailed description of each attribute code and a 
reference to other relevant information. 

The following tables are included in this data set: 
S_BFE 
S_Fld_Haz_Ar 
S_Fld_Haz_Ln 
S_Gen_Struct 
S_LOMR 
L_Stn_Start 
S_Wtr_Ar 
S_Wtr_Ln 
S_XS 
L_Wtr_Nm 
S_Base_Index 
S_Perm_Bmk 
S_PLSS_AR 
S_PLSS_LN 
S_Pol_Ar 
S_Pol_Ln 
S_Quad_Index 
S_Label_Ld 
S_Trnsport_Ln 
S_Label_Pt 

Distribution_Information: 
Distributor: 
Contact_Information: 
Contact_Organization_Primary: 
Contact_Organization: FEMA, Map Service Center 

Contact_Address: 
Address_Type: mailing address 
Address: P.O. Box 1038 
City: Jessup 
State_or_Province: Maryland 
Postal_Code: 20794-1038 


Country: USA 
Contact_Voice_Telephone: 1-800-358-9616 
Contact_Electronic_Mail_Address: www.fema.gov/msc 
Contact_Instructions: Data requests must include the full name of the community or county and 

the FIRM panel number(s) or the 7.5-minute series 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 DFIRMs that match this data set are available from FEMA at the Map 
Service Center, cited above. 
Digital_Form: 

Digital_Transfer_Information: 
Format_Name: ESRI Shapefile 
Format_Version_Number: 1 

Digital_Transfer_Option: 

Offline_Option: 
Offline_Media: CD-ROM 
Recording_Format: ISO 9660 

Digital_Form: 

Digital_Transfer_Information: 
Format_Name: MapInfo Interchange file (MIF) 
Format_Version_Number: 1 

Digital_Transfer_Option: 

Offline_Option: 
Offline_Media: CD-ROM 
Recording_Format: ISO 9660 

Digital_Form: 

Digital_Transfer_Information: 
Format_Name: ARCE 
Format_Version_Number: 1 

Digital_Transfer_Option: 

Offline_Option: 
Offline_Media: CD-ROM 
Recording_Format: ISO 9660 

Fees: Contact Distributor 

Metadata_Reference_Information: 
Metadata_Date: 19980509 
Metadata_Contact: 

Contact_Information: 
Contact_Organization_Primary: 

Contact_Organization: Federal Emergency Management Agency 
Contact_Position: Federal Insurance and Mitigation Administration 
Contact_Address: 

Address_Type: mailing address
Address: 500 C Street, S.W.
City: Washington
State_or_Province: District of Columbia
Postal_Code: 20472
Country: USA

Contact_Voice_Telephone: 1-800-358-9616 
Contact_Electronic_Mail_Address: www.fema.gov/msc 


Metadata_Standard_Name : FGDC Content Standards for Digital Geospatial Metadata 
Metadata_Standard_Version: FGDC-STD-001-1998 


L.9 Domain Tables 

This section contains a list of domain tables for the DFIRM Database. For Preliminary or Final 
DFIRM Databases, these tables list acceptable values for fields which are referenced to a domain 
table. For draft DFIRM data that follow the structure defined in Section L.4, these tables provide 
the contents for the domain tables included in that option. 

Note that if pre-existing data are used by the Mapping Partner for S_PLSS_Ar, S_PLSS_Ln, 
S_Trnsport_Ln, S_Wtr_Ar or S_Wtr_Ln, it is not necessary to limit field values to only the 
domains defined here for those tables. 

Table: D_Area_Units 

 
Table: D_CBRS_Typ

CBRS_LID CBRS_TYP 
1000 COASTAL BARRIER RESOURCES SYSTEM 
1010 OTHERWISE PROTECTED AREA 


Table: D_Chan_Rep

CHAN_LID CHAN_REP 
1000 SINGLE 
1010 DOUBLE 


Table: D_Discharge_Units

DISCH_LID DISCH_UNIT 
1000 CFS 
1010 CMS 
1020 GPD 
1030 GPM 


Table: D_Eros_Method

EROS_LID EROS_METH 
1010 NOT APPLIED 
1020 REMOVAL 
1030 RETREAT 


Table: D_Floodway

FLDWAY_LID FLOODWAY 
1000 FLOODWAY 
1010 COLORADO RIVER 
1020 FLOODWAY CONTAINED IN CHANNEL 
1030 FLOWAGE EASEMENT BOUNDARY 
1040 STATE ENCROACHMENT 
1050 AREA OF SPECIAL CONSIDERATION 


Table: D_Frequency

FREQ_LID FREQUENCY 
1001 0.2 PCT 
1002 1 PCT 
1003 2 PCT 
1004 4 PCT 
1005 10 PCT 
1006 1 PCT LEVEE 
1007 1 PCT LEVEE, RIGHT FAILED 
1008 1 PCT LEVEE, LEFT FAILED 
1009 1 PCT LEVEE, LEFT AND RIGHT FAILED 
1010 1 PCT WITH FLOODWAY 
1011 1 PCT WITHOUT FLOODWAY 


Table: D_Gage

GAGE_LID GAGE_TYPE 
1000 FLOW 
1010 FLOW / STAGE 
1020 STAGE 
1100 FIXED INTERVAL 
1110 INSTANTANEOUS 
1120 TIPPING 
1200 WAVE HEIGHT 
1210 WIND DIRECTION 
1220 WIND SPEED 
1230 WIND SPEED & DIRECTION 
1240 TIDE 


Table: D_Hydra

HYDRA_LID HYDRA_MDL 
1000 ADVANCED ICPR 2.20 (OCTOBER 2000) 
1001 DHM 21 (AUGUST 1987) 
1002 FEQ 8.92 (1997) 
1003 FEQUTL 4.68 (1997) 
1004 FESWMS 2DH 1.1 (JUNE 1995) 
1005 FLDWAV (NOVEMBER 1998) 
1006 FLDWY (MAY 1989) 
1007 FLO-2D V.2000.11 (DECEMBER 2000) 
1008 GAGE ANALYSIS 
1009 HCSWMM 4.31B (AUGUST 2000) 
1010 HEC-2 4.6.2 (MAY 1991) 
1011 HEC-RAS 2.2 (SEPTEMBER 1998) 
1012 HEC-RAS 3.0.1 
1013 HY8 4.1 
1014 HY8 6.0 
1015 MIKE 11 HD (JUNE 1999) 
1016 PSUPRO 
1017 QUICK -2 1.0 
1018 QUICK -2 2.0 
1019 SFD 
1020 SHEET 2D 9 (JULY 2000) 
1021 SWMM 4.30 (MAY 1994) 


HYDRA_LID HYDRA_MDL 
1022 SWMM 4.31 (JANUARY 1997) 
1023 TABS-RMA2 V.4.3 (OCTOBER 1996) 
1024 TABS-RMA4 V.4.5 (JULY 2000) 
1025 UNET 4.0 (APRIL 2001) 
1026 WSPGW 12.96 (OCTOBER 2000) 
1027 WSPRO (JUNE 1988) 


Table: D_Hydro

HYDRO_LID HYDRO_MDL 
2000 AHYMO 97 (AUGUST 1997) 
2001 CUHPF/PC (MAY 1996) 
2002 DBRM 3.0 (1993) 
2003 DR3M (OCTOBER 1993) 
2004 FAN 
2005 HEC-FFA 3.1 
2006 HEC-1 4.0.1 
2007 HEC-1 4.1 
2008 HEC-HMS 1.1 
2009 HEC-HMS 2.0 
2010 HEC-HMS 2.0.3 
2011 HEC-HMS 2.1.1 
2012 HEC-HMS 2.1.2 
2013 HEC-HMS 2.1.3 
2014 HEC-IFH 1.03 
2015 HEC-IFH 1.04 
2016 HEC-IFH 2.0 
2017 HEC-IFH 2.01 
2018 HSPF 10.10 
2019 HSPF 10.11 
2020 HSPF 11.0 
2021 HYMO 


HYDRO_LID HYDRO_MDL 
2022 MIKE 11 RR (JUNE 1999) 
2023 MIKE 11 UHM (JUNE 1999) 
2024 PEAKFQ 2.4 (APRIL 1998) 
2025 PEAKFQ 2.5 
2026 PEAKFQ 3.0 
2027 PEAKFQ 4.0 
2028 RATIONAL METHOD 
2029 REGRESSION EQUATIONS 
2030 SNYDER METHOD 
2031 SWMM (RUNOFF) 4.30 (MAY 1994) 
2032 SWMM (RUNOFF) 4.31 (JANUARY 1997) 
2033 TR-20 (FEBRUARY 1992) 
2034 TR-55 (JUNE 1986) 


Table: D_Label_Typ

LABEL_LID LABEL_TYPE 
1000 DOQ-TRANSPORTATION 
1010 DOQ-WATER 
1020 S_TRNSPORT_LN 
1030 S_WTR_AR 
1040 S_WTR_LN 


Table: D_Length_Units

 
Table: D_Ln_Typ 

Some lines may have multiple values. For the S_Pol_Ln table, the following precedence should 
apply: INTERNATIONAL, STATE, COUNTY, CORPORATE, EXTRATERRITORIAL 
JURISDICTION, URBAN GROWTH BOUNDARY, MUNICIPAL URBAN DRAINAGE 
DISTRICT, LEVEE IMPROVEMENT DISTRICT, AREA NOT INCLUDED, 
RESERVATION, FOREST, and PARK. 

For the S_Fld_Haz_Ln table, the following precedence should apply: LIMIT OF DETAILED 
STUDY, LIMIT OF STUDY, LIMIT OF FLOODWAY, FLOODWAY, 1 PCT ANNUAL-
CHANCE FLOOD HAZARD, ZONE BREAK, 0.2 PCT ANNUAL CHANCE FLOOD 
HAZARD, FLOWAGE EASEMENT BOUNDARY, and STATE ENCHROACHMENT LINE. 

For the S_PLSS_Ln table, the following precedence should apply: TOWNSHIP, RANGE, 
SECTION, QUARTER SECTION, and MEANDER. 

 
Table: D_Method

METH_LID METHOD 
1010 CUT FROM TOPO 
1020 DIGITIZED FROM FIRM 
1030 FIELD SURVEY 


Table: D_Nm_Typ

NM_LID NM_TYP 
1000 ALLEY 
1001 ARCADE 
1002 AVENIDA 
1003 AVENUE 
1004 BOULEVARD 
1005 BYPASS 
1006 CALLE 
1007 CAUSEWAY 
1008 CENTER 
1009 CIRCLE 
1010 COUNTY HIGHWAY 
1011 COURT 
1012 COVE 
1013 CRESCENT 
1014 CROSSING 
1015 DRIVE 
1016 ESTE 
1017 EXPRESSO 
1018 EXPRESSWAY 
1019 FREEWAY 
1020 HIGHWAY 
1021 INTERSTATE HIGHWAY 


NM_LID NM_TYP 
1022 LANE 
1023 LOOP 
1024 MOTORWAY 
1025 NORTE 
1026 OESTE 
1027 PARKWAY 
1028 PASEO 
1029 PASS 
1030 PATH 
1031 PIKE 
1032 PLACE 
1033 PLAZA 
1034 ROAD 
1035 ROW 
1036 RUE 
1037 SQUARE 
1038 STATE HIGHWAY 
1039 STREET 
1040 SUR 
1041 TERRACE 
1042 THROUGHWAY 
1043 TRAFFICWAY 
1044 TRAIL 


NM_LID NM_TYP 
1045 TURNPIKE 
1046 WAY 


Table: D_Nodes

NODE_LID NODE_TYPE 
1000 DIVERSION 
1010 JUNCTION 
1020 RESERVOIR 
1030 STRUCTURE 


Table: D_Panel_Typ

PANEL_LID PANEL_TYP 
1000 COUNTYWIDE, PANEL PRINTED 
1010 COUNTYWIDE, NOT PRINTED 
1020 COMMUNITY BASED, PANEL PRINTED 
1030 COMMUNITY BASED, NOT PRINTED 
1040 UNMAPPED COMMUNITY 


Table: D_Rd_Stat

RD_S_LID RD_STAT 
1000 PAVED 
1010 PROPOSED 
1020 UNDER CONSTRUCTION 
1030 UNIMPROVED 


Table: D_Runup_Mdl

RUNUP_LID RUNUP_MDL 
1010 ACES 1.07 (1992) 
1020 CHAMP (1.0) (2001) 
1030 EROSION (1998) 
1040 GLWRM (1992) 
1050 RUNUP 2.0 (1990) 


Table: D_Scale

SCALE_LID SCALE 
1000 6000 
1010 12000 
1020 24000 


Table: D_Shr_Rough

SHR_LID SHR_ROUGH 
1001 VERY LOW 
1002 LOW 
1003 MODERATE 
1004 HIGH 
1005 VERY HIGH 


Table: D_Shr_Typ

SHRTYP_LID SHRLN_TYP 
1001 ZERO FOOT CONTOUR FIELD SURVEY 
1002 ZERO FOOT CONTOUR LIDAR/SHOALS 


Table: D_Storms

STORM _LID STORM_TYPE 
1000 CHICAGO 
1010 DDF 
1020 HUFF 
1030 IDF 
1040 SANTA BARBARA 
1050 SCS TYPE I 
1060 SCS TYPE II 
1070 SCS TYPE IIA 
1080 SCS TYPE III 
1090 TRIANGULAR 
1100 UNIFORM 


Table: D_Struct_Typ

STRUCT_LID STRUCT_TYP 
1000 AQUEDUCT 
1001 BRIDGE 
1002 CANAL 
1003 CHANNEL 
1004 CHANNEL CONTAINS 0.2 PCT FLOOD EVENT 
1005 CHANNEL CONTAINS 1 PCT FLOOD EVENT 
1006 CONTROL STRUCTURE 
1007 CULVERT 
1008 CULVERT CONTAINS 0.2 PCT FLOOD EVENT 
1009 CULVERT CONTAINS 1 PCT FLOOD EVENT 
1010 DAM 
1011 DIKE 
1012 DOCK 
1013 DROP STRUCTURE 
1014 ENERGY DISSIPATER 
1015 FISH LADDER 
1016 FLOODWAY CONTAINED IN CHANNEL 
1017 FLUME 
1018 FOOTBRIDGE 
1019 GATE 
1020 JETTY 
1021 LEVEE 


Table: D_Surge_Mdl

SURGE_LID SURGE_MDL 
1010 DYNLET 
1020 FEMA SURGE (1988) 
1030 FLOW2D (1975) 
1040 MIKE 21 HD/NHD 
1050 NEW ENGLAND TIDE PROFILE 
1060 NORTHEASTER MODEL (1978) 
1070 ODISTIM (1975) 
1080 TABS RMA2 V.4.3 (OCTOBER 1996) 
1090 USACE GREAT LAKES TIDE PROFILE (1998) 


Table: D_Time_Units

TIME_LID TIME_UNIT 
1000 DAYS 
1010 HOURS 
1020 MINUTES 
1030 MONTHS 
1040 SECONDS 
1050 WEEKS 
1060 YEARS 


Table: D_Trans_Typ

TRANS_LID TRANS_TYP 
1000 UNDEFINED ROAD 
1001 PRIMARY ROAD 
1002 SECONDARY ROAD 
1003 TRAIL 
1010 ROAD TUNNEL 
1020 FORD 
2000 UNDEFINED RAILROAD 
2001 ACTIVE RAILROAD 
2002 ABANDONED RAILROAD 
2003 DISMANTLED RAILROAD 
2010 RAILROAD TUNNEL 
3000 AIRPORT 
4000 FERRY 


 Table: D_V_Datum

V_DATM_LID V_DATUM 
1000 MSL 
1010 NAVD88 
1020 NGVD29 


Table: D_Velocity_Units

VEL_LID VEL_UNIT 
1000 CENTIMETERS / DAY 
1010 CENTIMETERS / HOUR 
1020 FEET / SECOND 
1030 INCHES / DAY 
1040 INCHES / HOUR 
1050 METERS / SECOND 
1060 MICROMETERS / SECOND 
1070 MILLIMETERS / DAY 
1080 MILLIMETERS / HOUR 


Table: D_Volume_Units

VOL_LID VOL_UNIT 
1000 ACRE -FEET 
1010 CUBIC FEET 
1020 CUBIC METERS 
1030 CUBIC YARDS 
1040 GALLONS 
1050 LITERS 
1060 MILLION GALLONS 


Table: D_VZone

VZONE_LID VZONE_EXT 
1010 30 FOOT SPLASH ZONE BEHIND STRUCTURE 
1020 PFD 
1030 RUNUP EXTENT 
1040 WHAFIS 


Table: D_Water_Typ

WATER_LID WATER_TYP 
1000 AREA OF COMPLEX CHANNELS 
1001 ARTIFICIAL PATH 
1002 BAY / INLET 
1003 BAYOU 
1004 BOG 
1005 BYPASS / DIVERSION 
1006 CANAL / DITCH 
1007 CHANNEL 
1008 CONCRETE / EARTHEN CHANNEL 
1009 CONCRETE / EARTHEN DITCH 
1010 CONCRETE CHANNEL 
1011 CONCRETE DITCH 
1012 CONNECTOR 
1013 CREEK 
1014 CREVASSE FIELD 
1015 DETENTION POND 
1016 EARTHEN CHANNEL 
1017 EARTHEN DITCH 
1018 ESTUARY 
1019 FISH LADDER 
1020 FLUME 
1021 GULCH 


WATER_LID WATER_TYP 
1022 HATCHERY 
1023 ICE MASS / GLACIER 
1024 INTERMITTENT RIVER / STREAM 
1025 LAKE / POND 
1026 LOCK CHAMBER 
1027 MUD POT 
1028 NONEARTHEN SHORE 
1029 OVERFLOW 
1030 PERENNIAL RIVER / STREAM 
1031 PLAYA 
1032 PROFILE BASELINE 
1033 RACE 
1034 RESERVOIR 
1035 RETENTION POND 
1036 SAND PIT 
1037 SEA / OCEAN 
1038 SHORELINE / COASTLINE 
1039 SPILLWAY 
1040 STREAM / RIVER 
1041 SUBMERGED STREAM 
1042 SWAMP / MARSH 
1043 TAILINGS POND 
1044 UNDERPASS 


WATER_LID WATER_TYP 
1045 WASH 
1046 WASTE WATER LAGOON / POND 
1047 WATER SEPARATION LINE 
1048 WATERFALL 
1049 WATERWAY 
1050 WETLANDS 
1051 NAVIGABLE WATERWAY 
1052 SOUND 
1053 ISLAND 
1054 CHANNEL CONTAINS 1 PCT FL OOD EVENT 
1055 HYDROLOGIC LINK 
1056 PROFILE BASELINE AND STREAM CENTERLINE 
1057 STREAM CENTERLINE 


Table: D_Wave_Mdl

WAVEHT_LID WAVEHT_MDL 
1010 CHAMP 1.0 (2001) 
1020 MIKE 21 (OSW) 
1030 MIKE 21 (NSW) 
1040 RCPWAVE (1986) 
1050 WHAFIS 3.0 (1988) 
1060 WHAFIS 3.0 GL (1993) 


Table: D_Zone 

Where the 1-percent-annual-chance flood or the 0.2-percent-annual-chance flood is contained in 
a culvert or channel, a corresponding feature appears in the S_Fld_Haz_Ar table only if an 
SFHA or 0.2-percent-annual-chance flood zone is shown on the FIRM in this area. In general, 
these culverts and channels are to be represented in the general structure table regardless of how 
the flood insurance risk zones are depicted. So, if these structures are shown on the FIRM as a 
dashed line passing through a Zone X, no corresponding flood insurance risk zone is shown in 
S_Fld_Haz_Ar table in the DFIRM database. If a narrow SFHA or 0.2-percent-annual-chance 
flood zone is shown on the FIRM, then a narrow polygon must be included in the DFIRM 
database. If the width of this flood insurance risk zone is accurately known and represented in 
the spatial data, the normal flood insurance risk zone is applied. If the width of the flood 
insurance risk zone is not accurately known and represented because of scale limitations, then 
the zone is designated as 1-percent-annual-chance flood contained in channel or 0.2-percent-
annual-chance flood contained in channel as appropriate. 

ZONE_LID FLD_ZONE 
1000 A 
1001 AE 
1002 AH 
1003 AO 
1004 AR 
1005 1 PCT ANNUAL CHANCE FLOOD HAZARD CONTAINED IN CHANNEL 
1006 1 PCT FUTURE CONDITIONS 
1007 A99 
1008 V 
1009 VE 
2000 0.2 PCT ANNUAL CHANCE FLOOD HAZARD 
2001 0.2 PCT ANNUAL CHANCE FLOOD HAZARD CONTAINED IN CHANNEL 
3000 AREA NOT INCLUDED 
4000 D 


ZONE_LID FLD_ZONE 
4001 X PROTECTED BY LEVEE 
4002 X 
5000 OPEN WATER