All activities regulated by §
373-4 of this chapter, and not exempted by §
373-10, shall prepare a stormwater management site plan. The stormwater management site plan shall consist of all applicable calculations, maps and plans, including all plans, reports, and correspondence with the Lancaster County Conservation District. All stormwater management site plan materials shall be submitted to the municipality in a format that is clear, concise, legible, neat and well organized.
A. The following general information:
(1) Proposed name or identifying title of project.
(2) Name and address of the landowner and developer of the project site.
(3) Total acreage of the project site and the tract of land on which
the project site is located.
(4) A location map, for the purpose of locating the project site to be
developed, at a minimum scale of 2,000 feet to the inch, showing the
relation of the tract to adjoining property and to all streets and
Township boundaries existing within 1,000 feet of any part of the
tract of land on which the project site is proposed to be developed.
(5) Certificate for approval by the Township's authorized staff representative.
See form of certificate in the Appendix.
(6) A modification to a submitted stormwater management site plan that
involves a change in stormwater management BMPs or techniques, or
that involves the relocation or redesign of stormwater management
BMPs, or that is necessary because soil or other conditions are not
as stated on the stormwater management site plan as determined by
the municipality shall require a resubmission of the modified stormwater
management site plan in accordance with this article.
B. The following existing features:
(1) Tract boundaries showing distances, bearings and curve data, as located
by field survey or by deed plotting.
(2) Existing contours at vertical intervals of one foot for land with
an average slope of 0% to 3%, two feet for land with an average natural
slope of 4% to 20%, and at vertical intervals of five feet for land
with an average slope of 21% and greater; except that for residential
and agricultural uses where a preliminary subdivision or land development
plan is not required by the controlling subdivision and land development
ordinance, no contours shall be required; however, the plan should
indicate the natural drainage patterns of the site along with the
approximate grades of all slopes. Where contours are shown, the location
of the benchmark and the datum used shall also be indicated.
(3) The names of all owners of all immediately adjacent unplatted land,
the names of all proposed or existing developments immediately adjacent,
and the locations and dimensions of any streets or easements shown
thereon.
(4) The names, locations and dimensions of all existing streets, railroads,
watercourses, drainage facilities, floodplains, and other significant
features within 200 feet of any part of the tract proposed to be developed
and the location of all buildings and approximate location of all
tree masses within the tract.
(5) Soil types as designated by the USDA NRCS Soil Survey of Lancaster
County.
(6) The locations of all existing utilities (including on lot disposal
systems and wells), sanitary sewers, and water lines and associated
easements.
C. The following proposed features:
(1) The proposed land use, the number of lots and dwelling units and
the extent of commercial, industrial or other nonresidential uses.
(2) The locations and dimensions of all proposed streets, parks, playgrounds,
and other public areas; sewer and water facilities; lot lines and
building locations, and parking compounds and other impervious and
semipervious surfaces.
(3) The proposed changes to land surface and vegetative cover including
areas to be cut or filled.
(4) Final contours at vertical intervals of one foot for land with an
average slope of 0% to 3%, two feet for land with an average natural
slope of 4% to 20%, and at vertical intervals of five feet for land
with an average slope of 21% and greater.
(5) Where existing contours are not shown or where proposed contour lines
cannot be accurately located (i.e., as in a single-family detached
residential development when the building has not been determined),
arrows indicating general surface runoff flow patterns shall be shown.
D. The following stormwater management facilities and information:
(1) All storm sewers along with any proposed connections to existing
facilities.
(2) Groundwater recharge methods such as seepage pits, beds or trenches.
When these structures are used, the locations of septic tank infiltration
areas and wells must be shown.
(3) Other control devices or methods such as rooftop storage, grass swales,
parking lot ponding, vegetated strips, and detention or retention
basins.
(4) Plans and profiles of all proposed stormwater management facilities
including vertical and horizontal alignment, size and type of material.
This information shall be of the quality required for the construction
of all facilities.
(5) When plan applications, whether preliminary or final, are submitted
in sections, a generalized stormwater management site plan for the
entire project site shall be submitted in addition to the detailed
stormwater management site plan for the proposed section. This generalized
plan shall demonstrate how the stormwater of the proposed section
will relate to the entire development. The amount and velocity at
the discharge point of the section shall be included in the data submitted.
If temporary facilities are required for construction of a section,
such facilities shall be included in the submitted plans.
(6) A note on the plan indicating any area that is not to be offered
for dedication along with a statement that the Township is not responsible
for maintenance of any area not dedicated to and accepted for public
use, and that no alteration to swales, or basins, or placement of
structures shall be permitted within easements.
(7) A certificate, signed and sealed by an individual registered in the
Commonwealth of Pennsylvania and qualified under all applicable local
and state laws to perform such duties, indicating the compliance of
the design of the stormwater management facilities with the provisions
of this chapter.
(8) A declaration of adequacy/highway occupancy permit from the PennDOT
District Office when utilization of a PennDOT stormwater facility
is proposed.
(9) For any activities that require a DEP joint permit application and
are regulated under Chapter 105 or Chapter 106, require a PennDOT
Highway Occupancy Permit, or require any other permit under applicable
state or federal regulations, the permit(s) shall be part of the stormwater
management site plan and must be obtained prior to final plan approval.
E. Erosion and sedimentation controls. The type, location and extent of all erosion and sedimentation control measures shall be shown on an erosion and sedimentation control plan that conforms to the requirements of the Soil Erosion and Sedimentation Control Manual of the Pennsylvania Department of Environmental Protection and the Design Standards of §
373-20 of this chapter.
(1) Written report, including the following information.
(a)
Stormwater runoff calculations for both predevelopment and postdevelopment
conditions.
(b)
An erosion and sedimentation control plan narrative that conforms
to the requirements of the Soil Erosion and Sedimentation Control
Manual of the Pennsylvania Department of Environmental Protection
and provides a description of all erosion and sedimentation control
measures, temporary as well as permanent, including the staging of
earthmoving activities, sufficient in detail to clearly indicate their
function.
(c)
An ownership and maintenance program, in recordable form, that
clearly sets forth the ownership and maintenance responsibility of
all temporary and permanent stormwater management facilities, BMPs
and erosion and sedimentation control facilities, including:
[1]
Description of temporary and permanent maintenance requirements.
[2]
Identification of a responsible individual, corporation, association
or other entity for ownership and maintenance of both temporary and
permanent stormwater management and erosion and sedimentation control
facilities.
[3]
Establishment of suitable easements, a minimum of 20 feet wide
for access to all facilities.
[4]
The intent of these regulations is to provide private ownership
and maintenance of stormwater management and erosion and sedimentation
control facilities. Where the Township Supervisors accepts dedication
of stormwater management facilities, the Township Supervisors may
require the developer to establish, at the time of dedication, a maintenance
fund, in an amount determined by the Township, adequate for the perpetual
care of such facilities, including detention basins.
[5]
For all proposed detention basins and retention basins, except
temporary sedimentation basins, the documentation shall include a
plotting or tabulations of storage volumes with corresponding water
surface elevations and the outflow rates for those water surfaces.
[6]
For all proposed detention basins and retention basins, except
temporary sediment basins, documentation shall set forth the design
hydrograph, the shortcut routing method or a method of equal caliber
acceptable to the Township Engineer, utilized to determine the function
of the basin.
[7]
A Pennsylvania Department of Transportation Highway Occupancy
Permit for any stormwater management facility proposed within the
right-of-way of a state road.
(2) A note on the maps shall refer to the associated computations and
E&S Pollution Control Plan by title and date. The cover sheet
of the computations and E&S Pollution Control Plan shall refer
to the associated maps by title and date.
Prior to the final release of the financial security, the developer
shall provide the Township with one Mylar and two prints of the final
as-built plan showing the following:
A. Actual location of all concrete monuments which were set at all angle
breaks, points of curvature and tangents around the perimeter of the
total tract. When the outside perimeter of a tract falls within or
along an existing road right-of-way, then the right-of-way of that
roadway shall be monumented at the above-referenced points.
B. Actual location of all iron pins or drill holes in curbs for all
individual lot lines.
C. Actual cul-de-sac radius.
D. Actual horizontal and vertical location of cartway center line versus
right-of-way center line.
E. Actual location of floodplain by elevation and dimension from property
line.
F. Actual location and cross section of swales and accompanying easements.
G. Actual horizontal and vertical location of stormwater management
facilities, including type and size of storm drainage pipes.
H. Detention basin.
(1) Actual contours of the detention basin.
(2) Actual outlet structure details, including type, size and inverts
of outlet pipes.
(3) Actual elevation of the embankment and emergency spillway.
(4) A table showing the stage/storage/discharge curve for the constructed
conditions.
(5) A table providing a comparison of the approved design versus the
as-built discharge rates from all detention facilities.
I. When a digital submission of an as-built plan is required, all coordinates
as depicted on the plan shall be based on the Pennsylvania South Zone
State Plane Coordinate System (NAD83 for horizontal and NAVD88 for
vertical).
J. The as-built record plan submission shall include a certification
of completion signed by the owner's qualified professional verifying
that all permanent stormwater management BMPs have been constructed
according to the approved plans and specifications. If any qualified
licensed professionals contributed to the construction plans, then
a qualified licensed professional must sign the completion certificate.
[Added 8-1-2022 by Ord. No. 1-2022]
A. If the municipality determines that any requirement under this chapter cannot be achieved for a particular regulated activity, the municipality may, after an evaluation of alternatives, approve measures other than those in this chapter, subject to §
373-10.
B. Waivers or modifications of the requirements of this chapter may
be approved by the municipality if enforcement will exact undue hardship
because of peculiar conditions pertaining to the land in question,
provided that the modifications will not be contrary to the public
interest and that the purpose of this chapter is preserved. Cost or
financial burden shall not be considered a hardship. Modifications
may be considered if an alternative standard or approach will provide
equal or better achievement of the purpose of this chapter. A request
for modifications shall be in writing and accompany the stormwater
management site plan submission. The request shall provide the facts
on which the request is based, the provision(s) of this chapter involved
and the proposed modification.
C. No waiver or modification of any regulated stormwater activity involving
earth disturbance greater than or equal to one acre may be granted
by the municipality unless that action is approved in advance by the
Department of Environmental Protection (DEP) or the delegated county
conservation district.