A.
Encroachments, alterations and improvements.
(1)
No encroachment, alteration, or improvement of any kind shall be
made to any watercourse until all adjacent municipalities which may
be affected by such action have been notified, and until all required
permits or approvals have been first obtained from the PADEP, Bureau
of Dams, Waterways and Wetlands. In addition, the Federal Emergency
Management Agency and Department of Community and Economic Development
shall be notified prior to any alteration or relocation of any watercourse.
(2)
No encroachment, alteration, or improvement of any kind shall be
made to any watercourse unless it can be shown through a hydrology
and hydraulics study (H&H) that the activity will not reduce or
impede the flood-carrying capacity of the watercourse in any way.
B.
Any new construction, development, uses or activities allowed within
any identified floodplain area shall be undertaken in strict compliance
with the provisions contained in this chapter and any other applicable
codes, ordinances and regulations.
A.
Where a floodplain area has been identified, the following provisions
shall apply:
(1)
Within any FW (Floodway Area), no new construction, development,
use, activity, or encroachment of any kind shall be allowed, except
where the effect of such proposed activity on flood heights is fully
offset by accompanying improvements. No new construction or development
shall be allowed unless a permit is obtained from the PADEP, Bureau
of Dams, Waterways and Wetlands. A H&H study showing no rise shall
be provided for any project within the FW.
(2)
Within any designated FF (Flood Fringe Area), new construction and
other development, uses and activities shall be allowed, provided
that they are undertaken in strict compliance with the provisions
contained in this chapter and any other applicable codes, ordinances,
and regulations.
(3)
Within any FA (General Floodplain Area), for which no detailed profiles
or elevations have been provided, the following provisions shall apply:
(a)
No new construction or development shall be located within the
area measured 50 feet landward from the top of bank of any watercourse.
(b)
Within any designated FA, except for the provision of Subsection A(3)(a) above, new construction, and other development, uses, and activities shall be allowed, provided that they are undertaken in strict compliance with the provisions contained in this chapter, as well as any other applicable codes, ordinances, and regulations.
(c)
In determining the base (one-percent-annual-chance flood) flood
elevation, when federal, state or other acceptable sources are not
available, the applicant shall determine this elevation in accordance
with hydrologic and hydraulic engineering techniques.
[1]
The applicant shall also delineate a floodway area and provide
sufficient documentation to establish the base flood elevation of
each structure and demonstrate that his proposed activity, together
with all other existing and anticipated development, uses and activities,
will not increase the water surface elevation of the one-percent-annual-chance
flood more than one foot at any point. The engineering principle of
equal reduction of conveyance shall be used to make the determination
of increases in flood heights.
[2]
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 Engineer.
B.
Within any designated floodplain area, the following construction,
development, use, activity or encroachment shall be prohibited. A
variance to this requirement shall not be granted:
A.
Residential structures.
B.
Nonresidential structures.
(1)
Within any identified floodplain area, the elevation of the lowest
floor (including basement) of any new nonresidential structure shall
be 1 1/2 feet or more above the base flood elevation.
(2)
Any nonresidential structure, or part thereof proposing substantial
improvements, having a lowest floor (including basement) which is
not elevated to at least 1 1/2 feet above the base flood elevation
shall be floodproofed in a completely or essentially dry manner in
accordance with the W1 or W2 space classification standards contained
in the publication entitled "Flood Proofing Regulations" published
by the U.S. Army Corps of Engineers (June 1972, as amended December
1995) or with some other equivalent standard. All plans and specifications
for such floodproofing shall be accompanied by a statement certified
by a registered professional engineer or architect which states that
the proposed design and methods of construction are in conformance
with the above referenced standards.
(3)
Enclosed areas below the lowest floor (including basement) are prohibited.
The following minimum standards shall apply for all construction
proposed within any identified floodplain area:
A.
Fill. If fill is used, it shall:
(1)
Extend laterally at least 15 feet beyond the building line from all
points;
(2)
Consist of soil or small rock material only; sanitary landfills shall
not be permitted;
(3)
Be compacted to provide the necessary permeability and resistance
to erosion, scouring, or settling;
(4)
Be no steeper than one vertical to three horizontal feet, unless
substantial data justifying steeper slopes are submitted to and approved
by the Township Zoning Officer; and
(5)
Be used only to an extent to which it does not adversely affect adjacent
properties.
B.
Drainage facilities. Storm drainage facilities shall be designed
to convey the flow of stormwater runoff in a safe and efficient manner
without damage to persons or property. The system shall insure proper
drainage at all points along streets, and provide positive drainage
away from buildings. The system shall also be designed to prevent
the discharge of excess runoff onto adjacent properties.
C.
Water and sanitary sewer facilities and systems.
(1)
All new or replacement water and sanitary sewer facilities and systems
shall be located, designed and constructed to minimize or eliminate
flood damages and to prevent the infiltration of floodwaters into
the system and discharges from the system into floodwaters.
(2)
Sanitary sewer facilities and systems shall be designed and constructed
to prevent the discharge of untreated sewage into floodwaters. All
sanitary manholes shall contain adequate waterproof gaskets, liners,
waterproofing, etc., to prevent inflow.
(3)
No part of any on-site sewage disposal system shall be located within
any identified floodplain area except in strict compliance with all
state and local regulations for such systems. If any such system is
permitted, it shall be located so as to avoid impairment to it, or
contamination from it, during a flood.
D.
Other utilities. All other utilities such as gas lines, electrical
and telephone systems shall be located, elevated (where possible)
and constructed to minimize the chance of impairment during a flood.
E.
Streets. The finished elevation of all new streets shall be no less
than one foot above the base flood elevation.
F.
Storage. No materials that are buoyant, flammable, explosive or,
in times of flooding, could be injurious to human, animal, or plant
life shall be stored below regulatory flood elevation.
G.
Placement of buildings and structures. All buildings and structures
shall be designed, located, and constructed so as to offer the minimum
obstruction to the flow of water and shall be designed to have a minimum
effect upon the flow and height of floodwater.
H.
Anchoring.
(1)
All buildings and structures shall be firmly anchored in accordance
with accepted engineering practices to prevent flotation, collapse,
or lateral movement.
(2)
All air ducts, large pipes, storage tanks, and other similar objects
or components located below the regulatory flood elevation shall be
securely anchored or affixed to prevent flotation.
I.
Floors, walls, and ceilings.
(1)
Wood flooring used at or below the regulatory flood elevation shall
be installed to accommodate a lateral expansion of the flooring, perpendicular
to the flooring grain, without causing structural damage to the building.
(2)
Plywood used at or below the regulatory flood elevation shall be
of a marine or water-resistant variety.
(3)
Walls and ceilings at or below the regulatory flood elevation shall
be designed and constructed of materials that are water-resistant
and will withstand inundation.
(4)
Windows, doors, and other components at or below the regulatory flood
elevation shall be made of metal or other water-resistant material.
J.
Paints and adhesives.
(1)
Paints or other finishes used at or below the regulatory flood elevation
shall be of a marine or water-resistant quality.
(2)
Adhesives used at or below the regulatory flood elevation shall be
of a marine or water-resistant quality.
(3)
All wooden components (doors, trim, cabinets, etc.) shall be finished
with a marine or water-resistant paint or finishing material.
L.
Equipment. Water heaters, furnaces, air-conditioning and ventilating
units, and other electrical, mechanical or utility equipment or apparatus
shall not be located below the regulatory flood elevation.
M.
Fuel supply systems. All gas and oil supply systems shall be designed
to prevent the infiltration of floodwaters into the system and discharges
from the system into floodwaters. Additional provision shall be made
for the drainage of these systems in the event that floodwater infiltration
occurs.
A.
In accordance with the Pennsylvania Flood Plain Management Act,[1] and the regulations adopted by the Department of Community
and Economic Development as required by the Act, any new or substantially
improved structure which will be used for the production or storage
of any of the following dangerous materials or substances, or will
be used for any activity requiring the maintenance of a supply of
more than 550 gallons, or other comparable volume, or any of the following
dangerous materials or substances on the premises, or will involve
the production, storage, or use of any amount of radioactive substances,
shall be subject to the provisions of this section, in addition to
all other applicable provisions. The following list of materials and
substances are considered dangerous to human life:
(1)
Acetone.
(2)
Ammonia.
(3)
Benzene.
(4)
Calcium carbide.
(5)
Carbon disulfide.
(6)
Celluloid.
(7)
Chlorine.
(8)
Hydrochloric acid.
(9)
Hydrocyanic acid.
(10)
Magnesium.
(11)
Nitric acid and oxides of nitrogen.
(12)
Petroleum products (gasoline, fuel oil, etc.).
(13)
Phosphorus.
(14)
Potassium.
(15)
Sodium.
(16)
Sulfur and sulfur products.
(17)
Pesticides (including insecticides, fungicides, and rodenticides).
(18)
Radioactive substances, insofar as such substances are not otherwise
regulated.
[1]
Editor's Note: See 32 P.S. § 679.101 et seq.
B.
Within any FW (Floodway Area), any structure of the kind described in Subsection A above shall be prohibited.
All subdivision proposals and development proposals containing
at least 50 lots or at least five acres, whichever is the lesser,
in identified floodplain areas where base flood elevation data are
not available shall be supported by hydrologic and hydraulic engineering
analyses that determine base flood elevations and floodway information.
The analyses shall be prepared by a licensed professional engineer
in a format required by FEMA for a conditional letter of map revision
and letter of map revision. Submittal requirements and processing
fees shall be the responsibility of the applicant.
Special requirements for mobile homes, mobile homes located
in existing mobile home parks, all manufactured homes, including those
which have incurred substantial damage as the result of a flood, and
any improvements thereto, are as follows:
A.
Within any FW (Floodway Area), mobile and manufactured homes shall
be prohibited.
B.
Within any floodplain, mobile and manufactured homes shall be prohibited
within the area measured 50 feet landward from the top-of-bank of
any watercourse.
C.
Within any floodplain, where permitted, individual mobile or manufactured
homes to be located outside of mobile home parks, any minor expansions
or improvements to existing mobile parks, and any improvements to
such parks shall comply with the following requirements:
(1)
The stands or lots shall be elevated on compacted fill, or on pilings,
so that the lowest floor of the mobile or manufactured home will be
1 1/2 feet above the elevation of the one-percent-annual-chance
flood.
(2)
Adequate surface drainage shall be provided.
(3)
Adequate access for a hauler shall be provided.
(4)
Where pilings are used for elevation, the lots shall be large enough
to permit steps; piling foundations shall be placed in stable soil
no more than 10 feet apart; reinforcement shall be provided for pilings
that will extend for six feet or more above the ground level.
(5)
All mobile or manufactured homes and any additions thereto shall
be anchored to resist flotation, collapse, or lateral movements by
providing over-the-top and frame ties to ground anchors in accordance
with the American National Standards Institute and National Fire Protection
Association Standards as specified in the Standard for the Installation
of Mobile Homes Including Mobile Home Park Requirements (NFPA No.
401A-1974, ANSI A119.3-1975), as amended, for mobile homes in hurricane
zones or other appropriate standards such as the following:
(a)
Over-the-top ties shall be provided at each of the four corners
of the mobile or manufactured home, with two additional ties per side
at intermediate locations for units 50 feet or more length, one additional
tie per side for units less than 50 feet in length.
(b)
Frame ties shall be provided at each corner of the mobile or
manufactured home, with five additional ties per side at intermediate
locations for units 50 feet or more in length, and four additional
ties per side for units less than 50 feet in length.
(c)
All components of the anchoring system shall be capable of carrying
a force of 4,800 pounds.
(6)
An evacuation plan shall be prepared and filed with the Township
and with the county and state disaster preparedness authorities for
all mobile home parks located within or partially within a designated
floodplain.
