The Floodplain Conservation District shall consist of the following
specific areas/districts:
A. The Floodway Area/District shall be those areas identified as "floodway"
on the FIRM, as well as those 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.
The floodway 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.
(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) No new construction or development shall be allowed, unless a 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 and 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 the base flood elevations have been provided and a floodway
has been delineated.
(2) The 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. Community-identified flood hazard areas shall be those areas where
Horsham Township 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, and as revised from time to time.
D. The A Area/District shall be the areas identified as an A Zone on
the FIRM included in the FIS prepared by FEMA and for which no one-percent
annual chance flood elevations have been provided. For these areas,
elevation and floodway information from other federal, state, or other
acceptable source shall be used when available. Where other acceptable
information is not available, the elevation shall be determined by
using the elevation of a point on the boundary of the Floodplain Conservation
District 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.
E. The Shallow Flooding 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 and three feet. In Zones AO and AH,
drainage paths shall be established to guide floodwaters around and
away from structures on slopes.
With FEMA's prior approval, the Floodplain Conservation
District may be revised or modified by Township Council 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 Floodplain Administrator
in consultation with the Township Engineer, and any party aggrieved
by this decision or determination may appeal to the Zoning Hearing
Board. 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 occurred, 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.