The SWM site plan shall consist of a general description of the project, including calculations, maps, and plans. A note on the maps shall refer to the associated computations and erosion and sediment (E&S) control plan by title and date. The cover sheet of the computations and E&S control plan shall refer to the associated maps by title and date. All SWM site plan materials shall be submitted to the Township in a format that is clear, concise, legible, neat, and well organized; otherwise, the Township may not accept the SWM site plan for review. The following items shall be included in the SWM site plan:
(a)
General:
(1)
General description of the project.
(2)
All stormwater management facilities must be located on a plan and detailed description of proposed stormwater management techniques, including drainage and construction specifications of the materials to be used for the stormwater management facilities.
(3)
Complete hydrologic, hydraulic, and structural computations for all stormwater management facilities.
(4)
An erosion and sediment control plan. The applicant is required to obtain a letter of approval or adequacy from the Montgomery County Conservation District for the erosion and sediment control plan for all projects that propose greater than one acre of earth disturbance.
(5)
A general description of proposed nonpoint source pollution controls.
(6)
The SWM site plan application and completed fee schedule form and associated fee.
(7)
The SWM site plan checklist.
(b)
Maps:
(1)
Prepare an existing resource and site analysis map (ERSAM) showing environmentally sensitive areas including, but not limited to, steep slopes, ponds, lakes, streams, wetlands, hydric soils, vernal pools, stream buffers, floodplains, hydrologic soil groups, closed topographic depressions and recharge areas. Land development, existing recharge areas, and any other requirements specifically outlined in the municipal SALDO also shall be included.
(2)
Map(s) of the project area shall be submitted on twenty-four-inch-by-thirty-six-inch sheets and/or shall be prepared in a form that meets the requirements for recording at the offices of the Recorder of Deeds of Montgomery County. Map(s) for a stormwater management plan filed as part of a land development application shall meet the requirements for both the SALDO and this chapter. The contents of the map(s) shall include, but not be limited to:
A.
The location of the project relative to highways, municipal boundaries, or other identifiable landmarks.
B.
Existing contours at intervals of two feet or less. In areas of slopes greater than 10%, five-foot contour intervals may be used.
C.
Existing streams, lakes, ponds, or other waters of the commonwealth within the project area.
D.
Other physical features including flood hazard boundaries, stream buffers, existing drainage courses, areas of natural vegetation to be preserved, and the total extent of the upstream area draining through the site.
E.
Provisions for permanent access or maintenance easements for all physical SWM BMPs, such as ponds and infiltration structures, as necessary to implement the operation and maintenance (O&M) plan discussed in this section.
F.
The following signature block for the municipality: "(Municipal official or designee), on this date (Signature date), has reviewed and hereby certifies that the SWM Site Plan meets all design standards and criteria of the Municipal Ordinance No. (number assigned to ordinance)."
G.
A determination of site conditions in accordance with the BMP Manual. A detailed site evaluation shall be completed for projects proposed in areas of carbonate geology or karst topography, and other environmentally sensitive areas, such as brownfields.
H.
Plan and profile drawings of all SWM BMPs, including drainage structures, pipes, open channels, and swales.
I.
SWM site plan shall show the locations of existing and proposed on-lot wastewater facilities and water supply wells.
J.
The SWM site plan shall include an O&M plan for all existing and proposed physical stormwater management facilities. This plan shall address long-term ownership and responsibilities for O&M as well as schedules and costs for O&M activities.
K.
A justification must be included in the SWM site plan if BMPs other than green infrastructure methods and LID practices are proposed to achieve the volume, rate and water quality controls under this chapter.
L.
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.
M.
A north arrow.
N.
The total tract boundary and size with distances marked to the nearest foot and bearings to the nearest degree.
O.
Existing and proposed land use(s).
P.
A key map showing all existing man-made features beyond the property boundary that would be affected by the project.
Q.
Location of all open channels.
R.
Overland drainage patterns and swales.
S.
A fifteen-foot-wide access easement around all stormwater management facilities to provide ingress to and egress from a public right-of-way, where necessary, or appropriate at discretion of the Township.
T.
The location of all erosion and sediment control facilities.
U.
A note on the plan indicating the location and responsibility for maintenance of stormwater management facilities that would be located off site. All off-site facilities shall meet the performance standards and design criteria specified in this chapter located within this Township.
V.
The following note shall be placed on all plans which propose permanent BMPs: "The BMP facilities shown on these plans are a basic and perpetual part of the stormwater management system for the proposed site located in Lower Gwynedd Township, Montgomery County, and as such are to be protected and preserved in accordance with the approved plans by the owners, their successors and assigns of these lands. Lower Gwynedd Township and/or its agents reserve the right and privilege to enter upon these lands from time to time for the inspection of said facilities in order to determine that the structural and design integrity is being maintained and the proper operation and maintenance of the facility is being conducted."
W.
A statement, signed by the applicant, acknowledging that any revision to the approved drainage plan must be approved by the Township, and that a revised erosion and sediment control plan must be submitted to the Township and Montgomery County Conservation District for approval, if applicable.
X.
The following signature block for the Design Engineer:
"I, (Design Engineer), on this date (date of signature); hereby certify that this drainage plan meets all requirements of the Department of Environmental Protection's (DEP's) regulations and this Ordinance."
(c)
Supplemental information to be submitted to the Township:
(1)
The following information shall be submitted by the applicant and shall include:
A.
The overall stormwater management concept for the project designed.
B.
Stormwater runoff computations required by this chapter.
C.
Stormwater management techniques to be applied both during and after development.
D.
Expected project time schedule.
E.
Development stages or project phases, if so proposed.
F.
An operations and maintenance (O&M) plan in accordance with all applicable sections of this chapter.
(2)
A description of the effect of the project (in terms of runoff volumes and peak flows) on adjacent properties and on any existing municipal stormwater collection system that may receive runoff from the project site.
(3)
An approved highway occupancy permit from the Pennsylvania Department of Transportation (PennDOT) District office when drainage towards PennDOT property is proposed.
(d)
Stormwater management facilities: