(A) (1) The SWM Site Plan and SWM Site Report shall consist of all applicable calculations, maps and plans. All SWM Site Plan materials shall be submitted to the municipality in a format that is clear, concise, legible, neat and well organized; otherwise, the SWM Site Plan shall be rejected.
(2) Appropriate sections from the municipal subdivision and land development ordinance, and other applicable local ordinances, shall be followed in preparing the SWM Site Plan.
(B) SWM Site Plan shall include, but not be limited to:
(1) Plans shall be of one size and in a form that meets the requirements for recording in the office of the County Recorder of Deeds:
(a) Plans for tracts of less than 20 acres shall be drawn at a scale of one inch equals no more than 50 feet;
(b) Plans for tracts of 20 acres or more, plans shall be drawn at a scale of one inch equals no more than 100 feet; and
(c) All lettering shall be drawn to a size to be legible if the plans are reduced to half size.
(2) The name of the development; name and location address of the property site; name, address and telephone number of the applicant/owner of the property; and name, address, telephone number, email address and engineering seal of the individual preparing the SWM Site Plan:
(3) The date of submission and dates of all revisions;
(4) A graphical and written scale on all drawings and maps;
(5) A north arrow on all drawings and maps;
(6) A location map at a minimum scale of one inch equals 1,000 feet and illustrates the project relative to highways, municipalities or other identifiable landmarks;
(7) Metes and bounds description of the entire tract perimeter;
(8) Existing and final contours at intervals:
(a) Slopes less than 5%: no greater than one foot;
(b) Slopes between 5% and 15%: no greater than two feet; and
(c) Steep slopes, greater than 15%: five-foot contour intervals may be used.
(9) Perimeters of existing water bodies within the project area including stream banks, lakes, ponds, springs, field delineated wetlands or other bodies of water, sinkholes, flood hazard boundaries (FEMA delineated floodplains and floodways), areas of natural vegetation to be preserved, the total extent of the upstream area draining through the site and overland drainage paths. In addition, any areas necessary to determine downstream impacts, where required for proposed stormwater management facilities must be shown;
(10) The location of all existing and proposed utilities, on-lot wastewater facilities, water supply wells, sanitary sewers and water lines on and within 50 feet of property lines, including inlets, manholes, valves, meters, poles, chambers, junction boxes and other utility system components;
(11) A key map showing all existing human-made features beyond the property boundary that may be affected by the project;
(12) Soil names and boundaries with identification of the hydraulic soil group classification including rock outcroppings;
(13) Proposed impervious surfaces, structures, roads, paved areas and buildings, including plans and profiles of roads and paved areas and floor elevations of buildings;
(14) Existing and proposed land use(s);
(15) Horizontal alignment, vertical profiles and cross-sections of all open channels, pipes, swales and other BMPs;
(16) The location and clear identification of the nature of permanent stormwater BMPs;
(17) The location of all erosion and sedimentation control facilities, shown separately from the SWM Site Plan (typically an E&S Plan);
(18) A minimum 20-foot wide access easement around all stormwater management facilities that would provide ingress to and egress from a public right-of-way. In lieu of providing an easement to the public right-of-way, a note may be added to the plan granting the municipality or their designees access to all easements via the nearest public right-of-way;
(19) Construction details for all drainage and stormwater BMPs;
(20) Construction sequence;
(21) Identification of short-term and long-term ownership, operations and maintenance responsibilities; and
(22) Notes and statements:
(a) A statement, signed by the landowner, acknowledging that the stormwater BMPs are fixtures that cannot be altered or removed without prior approval by the municipality;
(b) A statement referencing the operation and maintenance (O&M) agreement and stating that the O&M agreement is part of the SWM Site Plan;
(c) A note indicating that record drawings will be provided for all stormwater facilities prior to occupancy, or the release of the surety bond;
(d) The following signature block for the registered professional preparing the Stormwater Management Plan:
“I, , hereby certify that the Stormwater Management Plan meets all design standards and criteria of the City of Corry’s Stormwater Management Ordinance.”
(e) The following signature block for the municipality reviewing the Stormwater Management Plan:
“I, , have reviewed this Stormwater Management Plan in accordance with the Design Standards and Criteria of the City of Corry’s Stormwater Management Ordinance.”
(C) SWM Site Report shall include (but not limited to):
(1) General data including:
(a) Project name;
(b) Project location, address of the property site;
(c) Name, address and telephone number of the applicant/owner of the property;
(d) Name, address, telephone number, email address and engineering seal of the individual preparing the SWM Site Report; and
(e) Date of submission and revisions.
(2) Project description narrative that clearly discusses the project and provides the following information, where applicable:
(a) Narrative.
1. Statement of the regulated activity describing what is being proposed. Overall stormwater management concept with description of permanent stormwater management techniques, including construction specifications and materials to be used for stormwater management facilities;
2. Expected project schedule;
3. Location map showing the project site and its location relative to release rate districts;
4. Detailed description of the existing site conditions, including a site evaluation completed for projects proposed in areas of carbonate geology or karst topography, and other environmentally sensitive areas such as brownfields;
5. Total site area, pre and post, which must be equal or have an explanation as to why it is not;
6. Total site impervious area;
7. Total off-site areas;
8. Number and description of stormwater management facilities;
9. Type of development;
10. Pre-development land use;
11. Whether site is a water quality sensitive (WQS) development;
12. Whether site is in a defined sensitive area;
13. Types of water quality and recharge systems used, if applicable;
14. Complete hydrologic, hydraulic and structural computations for all stormwater management facilities;
15. A written maintenance plan for all stormwater features including detention facilities and other stormwater management elements;
16. Identification of ownership and maintenance responsibility for all permanent stormwater management facilities; and
17. Other pertinent information, as required
(b) Summary tables.
1. Pre-development hydrologic soil group (HSG) assumptions, curve numbers (CN), computation of average slope, hydraulic length, computed time of concentration;
2. Existing conditions runoff volume and peak rate of runoff;
3. Post-development runoff volume and peak rate of runoff;
4. Undetained areas, areas to ponds;
5. Land use for each sub-area;
6. Hydrologic soil group (HSG) assumptions, curve numbers (CN);
7. Time of concentration computed for each sub-area;
8. Post-development peak rate of runoff routed to ponds and out;
9. Pond maximum return period design data, including maximum water surface elevation, berm elevation and emergency spillway elevation; and
10. Water quality depth and volume requirements.
(c) Calculations.
1. Complete hydrologic, hydraulic and structural computations, calculations, assumptions and criteria for the design of all stormwater BMPs;
2. Details of the berm embankment and outlet structure indicating the embankment top elevation, embankment side slopes, top width of embankment, emergency spillway elevation, perforated riser dimensions, pipe barrel dimensions and dimensions and spacing of antiseep collars;
3. Design computations for the control structures, (pipe barrel and riser, and the like);
4. A plot or table of the stage-storage (volume vs. elevation) and all supporting computations; and
5. Routing computations.
(d) Drawings.
1. Drainage area maps for all watersheds and inlets depicting the time of concentration path for both existing conditions and post-developed condition;
2. All stormwater management facilities must be located on a plan and described in detail including easements and buffers boundaries;
3. Reports that do not clearly indicate the above information may be rejected for review by the municipality and will be returned to the applicant;
4. Description of, justification, and actual field results for infiltration testing with respect to the type of test and test location for the design of infiltration BMPs;
5. The effect of the project, in terms of runoff volumes, water quality and peak flows, on surrounding properties and aquatic features and on any existing municipal stormwater collection system that may receive runoff from the project site;
6. Description of the proposed changes to the land surface and vegetative cover including the type and amount of impervious area to be added; and
7. Identification of short-term and long-term ownership, operation and maintenance responsibilities as well as schedules and costs for inspection and maintenance activities for each permanent stormwater or drainage BMP, including provisions for permanent access or maintenance easements.
(D) Supplemental information to be provided prior to recording of the SWM Site Plan, as applicable:
(1) Signed and executed operations and maintenance agreement (Appendix A);
(2) Signed and executed easements, as required for all on-site and off-site work;
(3) An Erosion and Sedimentation Control Plan and approval letter from the County Conservation District;
(4) A NPDES permit;
(5) Permits from PADEP and ACOE;
(6) Geologic assessment;
(7) Soils investigation report, including boring logs, compaction requirements and recommendations for construction of detention basins; and
(8) A highway occupancy permit from PennDOT when utilization of a PennDOT storm drainage system is proposed or when proposed facilities would encroach onto a PennDOT right-of-way.
(Ord. 1508, passed 12-20-2010)