1. (a)

   1. (1) The Federal Emergency Management Agency is the official source for all floodplain maps used in the Building Authority Division floodplain management program.
   2. (2) The Federal Emergency Management Agency began publishing flood hazard boundary maps for the United States in 1977.
   3. (3) These early maps were constructed from information obtained from other sources such as the United States Army Corps of Engineers, United States Geological Survey, United States Natural Resources Conservation Service, and other available sources.
   4. (4) In some instances, the data used to compile these source maps have not been updated in many years.
   5. (5) In many parts of the state, these older maps are still the effective maps in use.

2. (b)

   1. (1) The Federal Emergency Management Agency regularly reviews these maps and will issue updated maps periodically when new or better flood study information is available.
   2. (2) These maps will be designated by a community panel number and an effective date.
   3. (3) Some maps will be designated as Flood Hazard Boundary Maps (FHBM), Flood Insurance Rate Maps (FIRM), Special Flood Hazard Areas (SFHA), or other designations.

3. (c)

   1. (1) Maps are issued in several formats.
   2. (2) Some older maps will be printed on ledger size paper eleven inches by seventeen inches (11” x 17”) and are commonly referred to as “plates”.
   3. (3) Larger format maps are printed and folded much like a road map and are commonly referred to as a “panel”.
   4. (4) Newer maps are being issued in an electronic format and are referred to as a “DFIRM” or digital map.
   5. (5) Some maps are available for viewing and or purchasing at the Federal Emergency Management Agency website (www.fema.gov).

4. (d)

   1. (1) Due to the methodology of producing the original maps and the incorporation of better information from actual field studies, sometimes property which is shown in a known floodplain may actually be at an elevation that is above the established base flood elevation.
   2. (2) In these instances, the department or owner may submit an application to the Federal Emergency Management Agency to have the property in question removed from the floodplain for insurance purposes.
   3. (3) The Federal Emergency Management Agency evaluates these applications and may issue a letter of map amendment (LOMA) or letter of map revision (LOMR).
   4. (4) The actual map panel may not be redrawn to reflect this change until the next scheduled revision.

5. (e)

   1. (1) Some maps or portions of maps will show a floodplain boundary but will not show the elevations of the base flood.

   2. (2) In these cases, the Design Review Section may determine the approximate base flood elevation by one (1) or more of the following methodologies:

      1. (A) Contour interpolation;
      2. (B) Obtainment of a base flood elevation determination from another authoritative source;
      3. (C) Review of high water marks from previous flood events; or
      4. (D) Review of flood studies prepared by other governmental or private agencies.
   3. (3) In the absence of a base flood elevation determination by the Federal Emergency Management Agency, the Design Review Section determination will be the official determination for that specific site.

6. (f)

   1. (1) Some maps or portions of maps will show a floodplain boundary with base flood elevation data but will not indicate a designated floodway.
   2. (2) In these cases, the Design Review Section will use the established base flood elevations and may designate a portion of the floodplain as a floodway for the purpose of regulating the development in the floodplain.
   3. (3) The area selected and designated a regulatory floodway shall be based on the principle that the area chosen for the regulatory floodway must be designed to carry the waters of the base flood without increasing the water surface elevation of that flood more than one foot (1’) at any point in the floodplain.
   4. (4) The division-designated floodway will be the official determination for that specific project site.

7. (g)

   1. (1) Some areas of the state have not yet been mapped by the Federal Emergency Management Agency for flood hazard areas.
   2. (2) When a project site falls within an unmapped area, the Design Review Section will determine if the project site is located within a potential flood-prone or hazard area.
   3. (3) When the project site is determined to be in a flood hazard area, the department shall be required to relocate the project outside of the division-determined hazard area or to provide an engineering study to verify the site will not be in a hundred-year flood hazard area.

Codification Notes: "DFIRM" means digital flood insurance rate map.