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's 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.
[Added 1-10-2017 by Ord.
No. 2017-O-01]
(a) No encroachments, including fill, new construction, substantial improvements,
or other development shall be permitted in an AE Zone without floodway,
unless it has been demonstrated through hydrologic and hydraulic analysis
performed in accordance with standard engineering practice that the
proposed development together with all other existing and anticipated
development, would not result in an increase in flood levels within
the entire community during the occurrence of the base flood discharge.
(b) No new construction or development shall be located within the area
measured 50 feet landward from the top-of-bank of any watercourse.
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 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.
In the absence of any of the above data or documentation, the community
may require elevation of the lowest floor to be at least three feet
above the highest adjacent grade. 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 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.
[Amended 1-10-2017 by Ord. No. 2017-O-01]
D. Community-identified flood hazard areas shall be those
areas where Warrington 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.
The identified floodplain area may be revised or modified by the 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 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 §
181-21C for situations where FEMA notification is required.
[Amended at time of adoption of Code (see Ch. 1, General
Provisions, Art. I)]
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 Supervisors. 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.