R322.1.4 Establishing the Design Flood Elevation
The design flood elevation shall be used to define flood hazard areas. At a minimum, the design flood elevation shall be the higher of the following:
- The base flood elevation at the depth of peak elevation of flooding, including wave height, that has a 1-percent (100-year flood) or greater chance of being equaled or exceeded in any given year.
- The elevation of the design flood associated with the area designated on a flood hazard map adopted by the community, or otherwise legally designated.
If design flood elevations are not specified, the building official is authorized to require the applicant to comply with either of the following:
- Obtain and reasonably use data available from a federal, state or other source.
- Determine the design flood elevation in accordance with accepted hydrologic and hydraulic engineering practices used to define special flood hazard areas. Determinations shall be undertaken by a registered design professional who shall document that the technical methods used reflect currently accepted engineering practice. Studies, analyses and computations shall be submitted in sufficient detail to allow thorough review and approval.