[Ord. No. 1179, 5/2/2023]
1. The identified floodplain area shall be;
A. Any areas of Borough of Mechanicsburg, classified as special flood
hazard areas (SFHAs) in the Flood Insurance Study (FIS) and the accompanying
Flood Insurance Rate Maps (FIRMs) dated March 16, 2009, and issued
by the Federal Emergency Management Agency (FEMA) or the most recent
revision thereof, including all digital data developed as part of
the Flood Insurance.
2. The above referenced FIS and FIRMs, and any subsequent revisions
and amendments are hereby adopted by Borough of Mechanicsburg and
declared to be a part of this chapter.
[Ord. No. 1179, 5/2/2023]
1. 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 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 of more than one foot 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,
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. 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.
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.
[Ord. No. 1179, 5/2/2023]
The identified floodplain area may be revised or modified by the Council 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 §
8-501, Subsection
2, for situations where FEMA notification is required.
[Ord. No. 1179, 5/2/2023]
Should a dispute concerning any identified floodplain boundary
arise, an initial determination shall be made by the Borough of Mechanicsburg
and any party aggrieved by this decision or determination may appeal
to the Council. The burden of proof shall be on the appellant.
[Ord. No. 1179, 5/2/2023]
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.