Exemptions from the drainage plan requirements are as specified in §
163-6.
The following items shall be included in the drainage plan:
A. General.
(1) General description of project.
(2) General description of proposed permanent stormwater controls.
(3) The name and address of the project site, the name and address of
the owner of the property, and the name of the individual or firm
preparing the drainage plan.
(4) The date of the plan submission.
(5) A graphic and written scale of one-inch equals no more than 50 feet;
for tracts of 20 acres or more, the scale shall be one-inch equals
no more than 100 feet.
(7) The total tract boundary and size with distances marked to the nearest
foot and bearings to the nearest degree.
(8) Existing and proposed land use(s).
(9) A key map showing all existing man-made features beyond the property
boundary that maybe affected by the project.
B. Map(s) of the project area showing:
(1) The location of the project relative to highways, municipalities,
or other identifiable landmarks.
(2) Existing contours at intervals of two feet. In areas of steep slopes
(greater than 15%), five-foot contour intervals may be used. Off-site
drainage areas impacting the project including topographic detail.
(3) Streams, lakes, ponds, or other bodies of water within the project
area.
(4) Other features including flood hazard boundaries, existing drainage
swales, wetlands, closed depressions, sinkholes, and areas of natural
vegetation to be preserved.
(5) Locations of proposed underground utilities, sewers, and waterlines.
The locations of all existing and proposed utilities, sanitary sewers,
and waterlines within 50 feet of property lines of the project site.
(6) An overlay showing soil types and boundaries based on the county
soil survey, as applicable, latest edition. Any hydric soils present
on the site should be identified as such.
(7) An overlay showing geologic types, boundaries, and any special geologic
features present on the site.
(8) Proposed changes to land surface and vegetative cover.
(9) Proposed structures, roads, paved areas, and buildings.
(10)
Final contours at intervals of two feet. In areas of steep slopes
(greater than 15%), five-foot contour intervals may be used.
(11)
Stormwater management district boundaries applicable to the
site.
(12)
Clear identification of the location and nature of permanent
stormwater BMPs.
(13)
Horizontal and vertical profiles of all open channels, including
hydraulic capacity.
(15)
An adequate access easement around all stormwater BMPs that
would provide municipal ingress to and egress from a public right-of-way.
(16)
A schematic showing all tributaries contributing flow to the
site and all existing man-made features beyond the property boundary
that would be affected by the project.
(17)
The location of all public water supply wells within 400 feet
of the project and all private water supply wells within 100 feet
of the project.
C. Stormwater management controls and BMPs.
(1) All stormwater management controls and BMPs shall be shown on a map
and described, including:
(a)
Groundwater recharge methods such as seepage pits, beds, or
trenches. When these structures are used, the locations of septic
tank infiltration areas and wells shall be shown.
(b)
Other control devices or methods such as rooftop storage, semipervious
paving materials, grass swales, parking lot ponding, vegetated strips,
detention or retention ponds, storm sewers, etc.
(2) All calculations, assumptions and criteria used in the design of
the BMPs shall be shown.
(3) All site testing data used to determine the feasibility of infiltration
on a site.
(4) All details and specifications for the construction of the stormwater
management controls and BMPs.
(5) The following signature block must be added to the stormwater plan
for the Township Engineer:
(Township Engineer), on this date (date of signature), have
reviewed and hereby certify that the stormwater management site plan
meets all the design standards and criteria of the Stormwater Management
Ordinance," Ordinance No.- _____.
D. The BMP Operations and Maintenance Plan, as required in Article
VII, describing how each permanent stormwater BMP will be operated and maintained and the identity of the person(s) responsible for operations and maintenance. A statement must be included, signed by the landowner, acknowledging that the stormwater BMPs are fixtures that cannot be altered or removed without approval by the municipality.
E. A written description of the following information shall be submitted:
(1) Overall stormwater management concept for the project.
(2) Stormwater runoff computations as specified in this chapter.
(3) Stormwater management techniques and best management practices to
be applied both during construction and after development.
(4) A description of the proposed operation and maintenance procedures
for all permanent stormwater BMPs.
(5) Expected project time schedule.
F. A declaration of adequacy and highway occupancy permit from the PennDOT
District Office when utilization of a PennDOT storm drainage system
is proposed.
A modification to a drainage plan for a proposed development site which involves a change in control methods or techniques, or which involves the relocation or redesign of control measures, or which is necessary because soil or other conditions are not as stated on the drainage plan (as determined by the municipality) shall require a resubmission of the modified drainage plan consistent with §
163-23 subject to review per §
163-24 of this chapter.