The identified floodplain area shall consist of the following
specific areas:
A. FW (Floodway Area): the area identified as Floodway in the FIS which
represents the channel of a watercourse and the adjacent land areas
that must be reserved in order to discharge the base flood without
cumulatively increasing the water surface elevation by more than one
foot at any point. This term shall also include floodway areas which
have been identified in other available studies or sources of information
for those special floodplain areas where no floodway has been identified
in the FIS.
B. FF (Flood-Fringe Area): the areas identified as Zones AE and A1-30
in the FIS which are subject to inundation by the one-percent annual
chance flood event determined by detailed methods and have base flood
elevations (BFEs) shown.
C. FA (General Floodplain Area): the areas identified as Zone A in the
FIS for which no one-hundred-year flood elevations have been provided.
When available, information from other federal, state and other acceptable
sources shall be used to determine the one-hundred-year elevation,
as well as a floodway area, if possible. When no other information
is available, the one-hundred-year elevation shall be determined by
using a point on the boundary of the identified floodplain area which
is nearest the construction site in question. In lieu of the above,
the Township may require the applicant to determine the elevation
with hydrologic and hydraulic engineering techniques. Hydrologic and
hydraulic analyses shall be undertaken only by professional engineers
or others of demonstrated qualifications, who shall certify that the
technical methods used correctly reflect currently accepted technical
concepts. Studies, analyses, computations, etc., shall be submitted
in sufficient detail to allow a thorough technical review by the Township
of Allegheny.
The identified floodplain area may be revised or modified by
the Allegheny Township Board of Supervisors where studies or information
provided by a qualified agency or person documents the need for such
revision. However, prior to any such change, approval must be obtained
from the FEMA. Additionally, as soon as practicable, but not later
than six months after the date such information becomes available,
a community shall notify FEMA of the changes by submitting technical
or scientific data.
Should a dispute concerning any identified floodplain boundary
arise, an initial determination shall be made by the Township Planning
Commission and any party aggrieved by this decision may appeal to
the Board of Supervisors. The burden of proof shall be on the appellant.