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)
Within any floodway area, no new construction or development
within a Floodway Area shall be allowed, unless a variance is obtained
from the Lower Gwynedd Township Zoning Hearing Board, and 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 for which base flood
elevations have been provided.
(1)
The AE Area/District 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)
The AE Area/District without floodway 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 in the FIS but
no floodway has been delineated.
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 the 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
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.
(d) In lieu of the mapping provided 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.
The Floodplain Conservation District 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, 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, the
Township shall notify FEMA of the changes by submitting technical
or scientific data.
Prior to development occurring in areas where annexation or
other corporate boundary changes are proposed or have occurred, the
Township shall review flood hazard data affecting the lands subject
to boundary changes. The Township 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.