Other floodplain districts may be established under this chapter
and reflected on the floodplain zoning maps. These districts may include
general floodplain districts and flood storage districts.
A.
Applicability. The provisions for this district shall apply to all
floodplains for which flood profiles are not available or where flood
profiles are available but floodways have not been delineated. Floodway
and flood-fringe districts shall be delineated when adequate data
is available.
B.
Permitted uses. Pursuant to Subsection D, it shall be determined whether the proposed use is located within a floodway or flood-fringe area. Those uses permitted in floodway (§ 505-22) and flood-fringe areas (§ 505-26) are allowed within the general floodplain district, according to the standards of Subsection C, provided that all permits or certificates required under § 505-36 have been issued.
D.
Determining floodway and flood-fringe limits. Upon receiving an application
for development within the general floodplain district, the Zoning
Administrator shall:
(1)
Require the applicant to submit two copies of an aerial photograph
or a plan which shows the proposed development with respect to the
general floodplain district limits, stream channel, and existing floodplain
developments, along with a legal description of the property, fill
limits and elevations, building floor elevations and floodproofing
measures.
(2)
Require the applicant to furnish any of the following information
deemed necessary by the Department to evaluate the effects of the
proposal upon flood height and flood flows and regional flood elevation
and to determine floodway boundaries:
(a)
A typical valley cross section showing the stream channel, the
floodplain adjoining each side of the channel, the cross-sectional
area to be occupied by the proposed development, and all historic
high water information.
(b)
Plan (surface view) showing elevations or contours of the ground;
pertinent structure, fill or storage elevations; size, location and
layout of all proposed and existing structures on the site; location
and elevations of streets, water supply, and sanitary facilities;
soil types; and other pertinent information.
(c)
Profile showing the slope of the bottom of the channel or flow
line of the stream.
(d)
Specifications for building construction and materials, floodproofing,
filling, dredging, channel improvement, storage, water supply and
sanitary facilities.
(3)
Transmit one copy of the information described in Subsection D(1) and (2) to the Department regional office along with a written request for technical assistance to establish regional flood elevations and, where applicable, floodway data. Where the provisions of § 505-36B(3) apply, the applicant shall provide all required information and computations to delineate floodway boundaries and the effects of the project on flood elevations.
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.
A.
Applicability. The provisions of this section apply to all areas
within the flood storage district (FSD), as shown on the Official
Floodplain Zoning Map.
B.
Permitted uses. Any use or development which occurs in a flood storage district must meet the applicable requirements in § 505-27.
C.
Standards for development in flood storage districts.
(1)
Development in a flood storage district shall not cause an increase
equal to or greater than 0.01 of a foot in the height of the regional
flood.
(2)
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.
(3)
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 § 505-42 of this chapter.
(4)
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.
