The identified floodplain area shall consist of the following
specific areas:
A. The floodway area shall be those areas identified in the FIS and
the FIRM as floodway and which represent the channel of a watercourse
and the adjacent land areas that must be reserved in order to discharge
the base flood without 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 flood hazard areas where no floodway
has been identified in the FIS and FIRM.
(1) Within any floodway area, no encroachments, including fill, new construction,
substantial improvements, or other development shall be permitted
unless it has been demonstrated through hydrologic and hydraulic analysis
performed in accordance with standard engineering practice that the
proposed encroachment would not result in any increase in flood levels
within the community during the occurrence of the base flood discharge.
(2) Within any floodway area, no new construction or development shall
be allowed, unless the appropriate permit is obtained from the Department
of Environmental Protection Regional Office.
B. The AE Area/District shall be those areas identified as an AE Zone
on the FIRM included in the FIS prepared by FEMA for which base flood
elevations have been provided.
(1) The AE Area adjacent to the floodway shall be those areas identified
as an AE Zone on the FIRM included in the FIS prepared by FEMA for
which base flood elevations have been provided and a floodway has
been delineated.
(2) AE Area without floodway shall be those areas identified as an AE
zone on the FIRM included in the FIS prepared by FEMA for which base
flood elevations have been provided but no floodway has been determined.
(a)
No permit shall be granted for any construction, development,
use, or activity within any AE Area/District without floodway unless
it is demonstrated that the cumulative effect of the proposed development
would not, together with all other existing and anticipated development,
increase the BFE more than one foot at any point.
(b)
No new construction or development shall be located within the
area measured 50 feet landward from the top-of-bank of any watercourse,
unless the appropriate permit is obtained from the Department of Environmental
Protection Regional Office.
C. The A Area/District shall be those areas identified as an A Zone
on the FIRM included in the FIS prepared by FEMA and for which no
base flood elevations have been provided. For these areas, elevation
and floodway information from other federal, state, or other acceptable
sources shall be used when available. Where other acceptable information
is not available, the base flood elevation shall be determined by
using the elevation of a point on the boundary of the identified floodplain
area which is nearest the construction site. In lieu of the above,
the municipality 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 municipality.
D. The AO and AH Area/District shall be those areas identified as Zones
AO and AH on the FIRM and in the FIS. These areas are subject to inundation
by one-percent-annual-chance shallow flooding where average depths
are between one foot and three feet. In Zones AO and AH, drainage
paths shall be established to guide floodwaters around and away from
structures on slopes.
E. Community-identified flood hazard areas shall be those areas where
Township of Tinicum has identified local flood hazard or ponding areas,
as delineated and adopted on a "Local Flood Hazard Map" using best
available topographic data and locally derived information such as
flood of record, historic high water marks, soils or approximate study
methodologies.
The identified floodplain area may be revised or modified by the Board of Commissioners where studies or information provided by a qualified agency or person documents the need for such revision. However, prior to any such change to the special flood hazard area, approval must be obtained from 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 to the special flood hazard area by submitting technical or scientific data. See §
159-21B for situations where FEMA notification is required.
Should a dispute concerning any identified floodplain boundary
arise, an initial determination shall be made by the Floodplain Administrator
and any party aggrieved by this decision or determination may appeal
to the Board of Commissioners. The burden of proof shall be on the
appellant.
Prior to development occurring in areas where annexation or
other corporate boundary changes are proposed or have occulted, the
community shall review flood hazard data affecting the lands subject
to boundary changes. The community shall adopt and enforce floodplain
regulations in areas subject to annexation or corporate boundary changes
which meet or exceed those in 44 CFR 60.3.