Consistent with the declaration of legislative intent and statement of community development objectives found in §§
310-2 and
310-3 of Article
I of this chapter, it is the intent of this article to benefit the public health, safety and welfare by conserving and protecting areas of steep slopes from the harmful consequences of excessive clearing of vegetation, excessive grading and/or inappropriate development. In so doing, the Township shall be guided by the goals of the Township Comprehensive Plan, 1994, Open Space and Environmental Resource Protection Plan, and the following objectives:
A. Guard against property damage and personal injury and minimize the
potential for erosion, soil failure, stream siltation, and contamination
of surface waters caused by the misuse of steep slope areas.
B. Conserve existing woodlands for air and water quality benefits, to
provide habitat for wildlife, and to maintain the ecological balance
among the natural systems on steep slope areas.
C. Permit land uses by right that are compatible with protection of
steep slope areas and encourage the use of steep slope areas for open
space and conservation uses.
D. Prohibit development in steep slope areas wherever possible, and
require all land use, clearing, grading and construction to satisfy
performance standards that guard against potential harmful consequences.
E. Regulate the expansion of any land use or development that existed
on steep slope areas prior to enactment of these requirements.
F. Protect adjoining properties from harmful consequences of development
permitted under relief from the provisions of these requirements.
The Steep Slope Conservation Overlay District is established
as all those areas of the Township with a slope of 25% or more, referred
to as "steep slopes" or "steep slope areas." This district may be
referred to as the "Steep Slope District."
A. Steep slope map:
(1)
Areas of steep slopes shall be plotted on a map known as the
"Steep Slope Conservation Overlay District Map of Perkiomen Township
(Steep Slope Map)," as determined from United States Geological Survey
(USGS) maps to indicate the approximate boundaries of the Steep Slope
District.
(2)
The boundaries shown on the Steep Slope Map may be supplemented
or modified by boundaries determined by examination of one or both
of the following sources whenever a subdivision or land development
plan is submitted for review by the Township:
(a)
Contour maps prepared from aerial photography.
(b)
On-site survey prepared by a registered professional engineer
or surveyor.
(3)
Changes in the boundaries of the Steep Slope District may be
plotted as amendments to the Steep Slope Map when feasible.
B. Boundary delineation and interpretation:
(1)
Applicants shall show the boundaries of the Steep Slope District on all subdivision and land development plans, based on one or more of the sources listed in §
310-188A herein.
(2)
The Township Engineer shall decide whether or not the Steep
Slope District has been shown with sufficient accuracy on the applicant's
plans. Based on the Township Engineer's advice, the Township Zoning
Officer may require applicants to revise the boundaries shown on the
plans.
(3)
The burden of proving the correct boundary shall be on the appellant,
supported by engineering and/or surveying data or mapping, testimony
of a soil scientist, or other acceptable evidence.
The Steep Slope District shall be an overlay on all zoning districts
and shall function in accordance with the following:
A. For any lot or portion thereof lying within the Steep Slope District,
the regulations of the overlay district shall take precedence over
the regulations of the underlying district.
B. Should the underlying zoning of any lot or any part thereof which
is located in the Steep Slope District be changed through any legislative
or judicial action, such change shall have no effect on the overlying
Steep Slope District unless such change was included as part of the
original application.
C. Should the overlying Steep Slope District be declared inappropriate
to any lot through any legislative or judicial actions, such change
shall have no effect on the underlying zoning district.
D. All uses, activities and development occurring within any Steep Slope
District shall be undertaken only in strict compliance with the provisions
of this article, with all federal and state laws, and with all other
applicable Township codes and ordinances.
The following open space and conservation uses are permitted
by right, provided that they shall not include any structures, roads,
driveways, parking areas, construction or other development or grading
or clearing of vegetation:
A. Wildlife sanctuary, woodland preserve, arboretum and passive park
and recreation areas.
B. Game farm or hunting preserve.
C. Forestry and reforestation in accordance with recognized natural
resource and soil conservation practices.
D. Pasture and grazing land in accordance with recognized natural resource
and soil conservation practices.
E. Outdoor plant nursery or orchard in accordance with recognized natural
resource and soil conservation practices.
F. Cultivation and harvesting of crops in accordance with recognized
natural resource and soil conservation practices.
G. Front, side or rear yards and required lot area for any district, subject to the requirements of §
310-193, Development regulations, and provided such yards shall not be used for any use prohibited under §
310-192 herein.
H. Nonstructural accessory uses necessary to the operation and maintenance
of the above-permitted uses.
The following uses shall be permitted on steep slopes of 25% or more when authorized by the Board of Supervisors as conditional uses in accordance with §
310-53 of Article
VIII and with the conditional use standards and criteria in §
310-194 herein:
A. Structures, roads, driveways, parking areas and underground utilities,
except that under no circumstances shall more than 50% of the driveway
traverse regulated steep slopes.
B. Clearing of vegetation or grading, including the addition of fill
composed of earth, rock or inorganic construction debris.
C. Sealed public water supply wells with approval of the Pennsylvania
Department of Environmental Protection.
D. Storm sewers and stormwater detention basins with the approval of
the Township Engineer and the Pennsylvania Department of Environmental
Protection (if applicable).
E. On-site sewage disposal systems, when approved by the Pennsylvania
Department of Environmental Protection and/or the Montgomery County
Department of Health (if applicable).
F. Utility transmission lines and aboveground utility line structures.
G. Extractive uses and borrow pits in accordance with recognized conservation
practices and regulations of the Pennsylvania Department of Environmental
Protection.
H. Public sanitary sewers with the approvals of the Township Engineer,
Authority Engineer and Pennsylvania Department of Environmental Protection
(if applicable).
Applications for conditional uses shall comply with the procedures in §
310-53 of Article
VIII of this chapter and provide the following information and documentation:
A. A plan by a registered professional engineer or surveyor which accurately
locates the proposed use with respect to the Steep Slope District
boundaries and existing development within 200 feet of the proposed
use, together with all pertinent information describing the proposal
and a topographical survey with contour elevations at no greater than
five-foot intervals.
B. A plan of proposed development or use of the site conforming to the preliminary plan requirements of Chapter
264, Subdivision and Land Development, with contours shown at two-foot intervals, throughout the steep slope areas proposed for development or use. Contours shall be accurately drawn from on-site survey or aerial photographic sources.
C. Proposed modifications to the existing topography and vegetative
cover as well as the means of accommodating stormwater runoff.
D. Documentation of any additional engineering and/or conservation techniques
designed to alleviate environmental problems created by the proposed
activities, in compliance with the Township's sedimentation and erosion
control regulations.
E. A table shall be provided on the plan, containing the amount of total
regulated steep slope area in acres and/or square feet and a total
of proposed disturbed area of steep slopes in acres and/or square
feet. This table shall be shown on the plan presented for the conditional
use and on the approved development plans. The maximum amount of steep
slope disturbance shall not exceed 5% of the total lot area.
F. The following, as deemed necessary by the Board of Supervisors:
(1)
Typical tract cross sections at a vertical and horizontal scale
deemed appropriate by the Township Engineer.
(2)
Specifications of building materials and construction, including
filling, grading, materials storage, water supply, and sewage disposal
facilities.
In considering a conditional use application, the Board of Supervisors
shall consider the following:
A. Relationship of the proposed use to the objectives set forth in §
310-187.
B. Adverse effects on abutting properties.
C. The need for a woodland management plan on wooded steep slopes areas. This plan shall utilize the plant materials listed in Chapter
264, Subdivision and Land Development. Substitutions to this list must be approved by the Township.
D. Evidence that:
(1)
Proposed buildings or structures are of sound engineering design
and that footings are designed to extend to stable soil and/or bedrock
and that the proposal will be sound from architectural, engineering
and environmental perspectives and will have no adverse impacts on
the health, safety and welfare of the community.
(2)
Proposed roads, drives and parking areas are designed so that
land clearing and/or grading will not cause accelerated erosion. Both
vertical and horizontal alignment for such facilities shall be so
designed that hazardous conditions are not created.
(3)
Alternative placements on non-steep-slope areas were carefully
evaluated for structures, including buildings, retaining walls, swimming
pools, roads, access driveways, parking facilities and other development,
and can be shown to be inappropriate or infeasible to the satisfaction
of the Board of Supervisors.
(4)
Proposed on-lot sewage disposal facilities are properly designed
in conformity with applicable regulations.
(5)
Proposed nonagricultural displacement of soil is for purposes
consistent with the intent of this chapter and will be executed in
a manner that will not cause erosion or other unstable conditions.
The applicant shall provide an erosion and sediment control plan and
supporting evidence.
(6)
Surface runoff of water will not create unstable conditions,
including erosion, and that appropriate stormwater management facilities
will be constructed as necessary.
At the conclusion of work done pursuant to an approval obtained
under this article, an as-built plan prepared by a surveyor or engineer
registered in the Commonwealth of Pennsylvania shall be submitted
to the Township. The plan shall be subject to review and approval
by the Township Zoning Officer and/or the Township Engineer. No certificate
of completion or certificate of occupancy shall be issued until the
as-built plan has been approved.
The granting of a certificate of occupancy, certificate of completion,
or the approval of a subdivision or land development plan on or near
the Steep Slope District shall not constitute a representation, guarantee
or warranty of any kind by the Township or any official or employee
thereof regarding the practicability or safety of the proposed use
and shall create no liability upon the Township, its officials or
its employees. Protections provided by this article are reasonable
for regulatory purposes and are based on engineering and scientific
studies. The article does not imply that areas outside the Steep Slope
District are free from the adverse effects of erosion and sedimentation.