The flood storage district delineates that portion of the floodplain where storage of floodwaters has been taken into account and is relied upon to reduce the regional flood discharge. The district protects the flood storage areas and assures that any development in the storage areas will not decrease the effective flood storage capacity, which would cause higher flood elevations.
The provisions of this article apply to all areas within the flood storage district (FSD), as shown on the Official Floodplain Zoning Maps.
Any use or development which occurs in a flood storage district must meet the applicable requirements in § 466-17.
Development in a flood storage district shall not cause an increase in the height of the regional flood.
No development shall be allowed which removes flood storage volume unless an equal volume of storage as defined by the predevelopment ground surface and the regional flood elevation shall be provided in the immediate area of the proposed development to compensate for the volume of storage which is lost (compensatory storage). Excavation below the groundwater table is not considered to provide an equal volume of storage.
If compensatory storage cannot be provided, the area may not be developed unless the entire area zoned as flood storage district – on this waterway – is rezoned to the flood-fringe district. This must include a revision to the floodplain study and map done for the waterway to revert to the higher regional flood discharge calculated without floodplain storage, as per Article X, Amendments, of this chapter.
No area may be removed from the flood storage district unless it can be shown that the area has been filled to the flood-protection elevation and is contiguous to other lands lying outside of the floodplain.