CHESAPEAKE BAY POLLUTANT REDUCTION PLAN FOR NORTH MIDDLETON TOWNSHIP

Transcription

1 369 East Park Drive Harrisburg, PA (717) July 2017 CHESAPEAKE BAY POLLUTANT REDUCTION PLAN FOR NORTH MIDDLETON TOWNSHIP PREPARED FOR: NORTH MIDDLETON TOWNSHIP CUMBERLAND COUNTY, PENNSYLVANIA HRG Project No. R Herbert, Rowland & Grubic, Inc., 2017

2 CHESAPEAKE BAY POLLUTION REDUCTION PLAN FOR NORTH MIDDLETON TOWNSHIP, CUMBERLAND COUNTY, PENNSYLVANIA TABLE OF CONTENTS Introduction Section A Public Participation Section B Maps Section C Pollutants of Concern Section D Determine Existing Loading for Pollutants of Concern Section E BMP to Achieve the Required Pollutant Load Reductions Section F Funding Mechanisms Section G BMP Operations and Maintenance Appendices Appendix A Public Participation Documentation Appendix B Mapping Appendix C PADEP Municipal MS4 Requirements Table Appendix D Existing Pollutant Loading Calculations Appendix E Proposed BMP Pollutant Load Reduction Calculations

3 Page 1 Introduction North Middleton Township discharges stormwater to surface waters located within the Chesapeake Bay watershed and is therefore regulated by PAG-13 General Permit, Appendix D (nutrients and sediment in stormwater discharges to waters in the Chesapeake Bay watershed). The Township also has watershed impairments regulated by PAG-13 General Permit, Appendix E (nutrients and/or sediment in stormwater discharges to impaired waterways). This Chesapeake Bay Pollutant Reduction Plan (CBPRP) was developed in accordance with both PAG-13 requirements and documents how the Township intends to achieve the pollutant reduction requirements listed in the Pennsylvania Department of Environmental Protection (PADEP) Municipal MS4 Requirements Table 1. This document was prepared following the guidance provided in the PADEP National Pollutant Discharge Elimination System (NPDES) Stormwater Discharges from Small Municipal Separate Storm Sewer Systems Pollutant Reduction Plan (PRP) Instructions 2. Notwithstanding that the prevailing guidance is associated with the General Permit, the Township is required to operate under an Individual Permit, to be issued upon review by PADEP, which is anticipated to include similar conditions to those included in the General Permit. The Township is required to operate under an Individual Permit because a portion of the Township drains to a high quality watershed (Letort Spring Run). GENERAL INFORMATION Permittee Name: North Middleton Township NPDES Permit No.: to be determined upon approval Mailing Address: 2051 Spring Road Effective Date: March 16, 2018 City, State Zip: Carlisle, PA Expiration Date: March 16, 2023 MS4 Contact Person: Deborah Ealer Renewal Due Date: Sept 16, 2022 Title: Township Manager Municipality: North Middleton Township Phone: (717) County: Cumberland dealer@nmiddleton.com Consultant Name: Herbert, Rowland & Grubic, Inc. Consultant Contact: Erin Letavic, P.E. 369 East Park Drive Co-Permittees (if applicable): N/A Harrisburg, PA (717) eletavic@hrg-inc.com North Middleton Township is a small MS4 community that will be starting its first permit term in March The Township is approximately 30-percent developed and has 4,768.9 acres of urbanized area (UA) according to the United States Census Bureau s 2010 census. North Middleton Township is located in the -Conodoguinet Creek, Letort Spring Run, and Alexanders Spring Creek HUC-12 watersheds. The -Conodoguinet Creek and Alexanders Spring Creek watersheds have been classified as 1 PADEP, MS4 Requirements Table (Municipal) (rev. 5/9/2017) 2 PADEP PRP Instructions; Document # 3800-PM-BCW0100k (rev. 3/2017)

4 Page 2 impaired by PADEP, therefore the Pollution Reduction Plan (PRP) requirements for these impaired watersheds are included as part of this CBPRP.

5 Page 3 Section A: Public Participation A complete copy of this CBPRP was made available for public to review at the North Middleton Township municipal office from August 1, 2017 to August 31, The availability of the document was publicized in The Sentinel on August 1, The published public notice contained a brief description of the plan, the dates and locations at which the plan was available for review by the public, and the length of time provided for the receipt of comments. A copy of the public notice will be included in Appendix A. Public comments will be accepted for 30 days following the publication date of the public notice. The number of public comments received will be included in the final version of this report. Additionally, copies of all public comments and the responses issued to each comment will be included in Appendix A. The information contained in this report was presented to the public during the regularly scheduled North Middleton Township Board of Supervisor s meeting held on August 3, Comments and questions regarding the CBPRP were received during the public presentation. A copy of the meeting minutes for the meeting at which the CBPRP was presented are included in Appendix A.

6 Page 4 Section B: Maps The North Middleton Township Planning Area Map depicts the Township s regulated outfalls and its contributing Municipal Separate Storm Sewer System (MS4) where possible to be mapped, as required under MCM #3, BMPs 2 and 3 of the PAG-13. It is anticipated that any remaining unmapped areas of the Township planning area will be fully mapped during the course of the five-year permit term. In addition to the MS4 infrastructure (inlets, pipes, outfalls, existing BMPs, etc.), the Planning Area Map also shows the CBPRP planning area, UA boundary, watershed boundaries, and proposed BMP locations. The Township s Land Use Map was developed using the most recent National Land Cover Database 3. The northern portion of the Township is undeveloped with large portions of agricultural and forested land. The majority of Township development is located in the southern portion of the municipality along the boundary with Carlisle Borough. Development within the southeastern part of the Township is mostly low-intensity residential and higher density commercial development in located within the southwestern portion of the Township. 3 Multi-Resolution Land Characteristics (MRLC) Consortium, National Land Cover Database 2011 (NLCD 2011)

7 Page 5 Section C: Pollutants of Concern The pollutants of concern for North Middleton Township were determined by referencing the PADEP MS4 Municipal Requirements Table 4 (Table 1). The applicable section of this table is included for reference in Appendix C. Table 1. Pollutants of Concern Impaired Downstream Water Chesapeake Bay Nutrients/Sediment Alexanders Spring Creek Pollutants of Concern Appendix D - Nutrients, Siltation (4a) Appendix E - Siltation (4a) Appendix E - Siltation (4a) 4 PADEP, MS4 Requirements Table (Municipal) (rev. 5/9/2017)

8 Page 6 Section D: Determine Existing Loading for Pollutants of Concern D.1 Parsed Area Calculation In order to calculate the actual pollutant loads applicable to the Township MS4, the PRP Instructions allow areas that do not drain to the MS4 and areas that are already covered by an NPDES permit to be removed from the CBPRP and PRP planning areas, a process called parsing 5. The following areas were parsed from the CBPRP and PRP planning areas: PennDOT Roadways The impervious area attributed to state roadways located within the Township was parsed from the existing pollutant base load, as PennDOT maintains their own MS4 permit to account for stormwater runoff generated from their system. Military Installation Areas The U.S. Army Garrisons, Carlisle Barracks (US Army War College) and Pennsylvania National Guard Armory are located within the southern portion of Township. These facilities are covered under separate MS4 permits through the state and federal agencies that operate and maintain the War College and Armory. Direct Discharge Areas Direct discharge areas are areas in which stormwater runoff does not enter the Township MS4. The area in the central and western portion of the Township, between I- 76 and the Conodoguinet Creek, has no existing MS4 infrastructure nor does it drain to the MS4. Therefore, this area was removed from the PRP and CBPRP planning areas. Additional smaller direct discharge areas along the Conodoguinet Creek in the eastern portion of the Township were also parsed from the Township planning areas. A summary of areas parsed from each planning area is shown in Tables 2A C. Parsed areas are shown on the CBPRP Planning Area Map (Appendix B) and supporting calculations for the pollutant loads associated with each parsed area are included in Appendix D. Table 2A. Parsed Area Summary CBPRP Planning Area Urbanized Planning Area Area CBPRP 4,769 Parsed Areas (PennDOT Roadways) Parsed Areas (Military Properties) Parsed Areas (Direct Drainage) - 1,734 Adjusted Planning Area 2,628 5 PADEP - PRP Instructions, Attachment A: Parsing Guidelines for MS4s in Pollutant Reduction Plans (rev. 3/2017)

9 Page 7 Table 2B. Parsed Area Summary Planning Area Urbanized Planning Area Area 3,842 Parsed Areas (PennDOT Roadways) Parsed Areas (Direct Drainage) - 1,694 Adjusted Planning Area 2,046 Table 2C. Parsed Area Summary Alexanders Spring Creek Planning Area Urbanized Planning Area Area Alexanders Spring Creek 286 Parsed Areas (PennDOT Roadways) - 27 Parsed Areas (Direct Drainage) - 41 Adjusted Planning Area 218 D.2 Existing Pollutant Load Calculation The existing loading in pounds per year was calculated using the Simplified Method 6. In accordance with this method, the adjusted UA from Tables 2A-C was multiplied by the percent pervious and impervious land use values for North Middleton Township listed in the Statewide MS4 Land Cover Estimates guidance document from PADEP 7. This calculation determined the acres of impervious and pervious land within each planning area. The impervious and pervious acreages were then multiplied by the Developed Land Loading Rates for Cumberland County 8 to determine the total existing pollutant load attributed to the Township. The existing pollutant loading was determined for the CBPRP planning area as well as for each impaired watershed (PRP planning areas). The UA within each planning area was determined using GIS software and the following layers: 2010 urbanized area (U.S. Census); municipal boundaries (Cumberland County GIS) and MS4 system (North Middleton Township). As stated previously in Section C, the pollutants of concern are TSS, TN, and TP; however, it is presumed that within the overall Bay watershed, the TP and TN goals will be achieved when the permit-required sediment reduction achieved. Therefore, only the TSS pollutant loading was calculated (Table 3). Detailed pollutant load calculations are provided in Appendix D. 6 PADEP PRP Instructions - Attachment C Chesapeake Bay PRP Example Using DEP Simplified Method 7 PADEP - Statewide MS4 Land Cover Estimates 8 PADEP - PRP Instructions, Attachment B: Developed Land Loading Rates for PA Counties (rev. 3/2017)

10 Page 8 Table 3. Pollutant Loading for North Middleton Township Planning Areas Planning Area UA Regulated Pollutant Load TSS (lbs/yr) CBPRP (entire regulated Township planning area) 2,628 1,783,502 PRP 2,046 1,395,462 Alexanders Spring Run PRP ,328 As the Alexanders Spring Run and planning areas are located within the overall CBPRP planning area, it is noted that the pollutant loads associated with the impaired watershed planning areas are a portion of, and not in addition to, the CBPRP planning area pollutant load. D.3 Existing Pollutant Loading Adjustment for Previously Implemented BMPs North Middleton Township contains several BMPs that have been installed previously and continue to function as designed. These BMPs treat a combined total of approximately 100 acres of UA and are being claimed as credit to reduce the existing baseline loading (Table 4). The pollutant loading reduction for existing BMPs were calculated in terms of pounds per year using PADEP s standard BMP Effectiveness Values 9. Additional information on existing BMPs is provided in Appendix D. The locations of existing BMPs are shown on the CBPRP Planning Area Map (Appendix B). Table 4: Adjusted Baseline Load Summary Planning Area Pollutant Load TSS (lbs/yr) Installed BMP Reduction TSS (lbs/yr) Adjusted Pollutant Load TSS (lbs/yr) CBPRP 1,783,502-27,273 1,756,229 PRP 1,395,462-18,297 1,377,165 Alexanders Spring Run PRP 134,328-8, ,352 9 PADEP Document 3899-PM-BCW0100M, NPDES Stormwater Discharges from Small MS4s, BMP Effectiveness Values (5/2015)

11 Page 9 Section E: BMPs to Achieve the Required Pollutant Load Reductions E.1 Required Pollutant Load Reduction Calculation North Middleton Township discharges stormwater to surface water located within the Chesapeake Bay watershed and is, therefore, regulated by PAG-13 General Permit, Appendix D (nutrients and sediment in stormwater discharges to waters in the Chesapeake Bay watershed). The pollutants of concern for Appendix D are TSS, TP, and TN with required loading reductions of 10-percent, 5-percent, and 3-percent, respectively. However, as stated previously, it is presumed that within the overall Bay watershed, the TP and TN goals will be achieved when a 10-percent reduction in sediment is achieved 10. Therefore, only the required 10-percent TSS reduction is calculated herein as a requirement for planning area load reductions (Table 5). The pollutant load reduction requirements listed below take into account adjustments to baseline loading from the parsed areas and existing BMPs discussed in Section D. Table 5: Required Pollutant Load Reduction Goals CBPRP Planning Area Planning Area UA Required Load Reduction TSS (lbs/yr) CBPRP 2, ,623 In addition to meeting the PAG-13 General Permit, Appendix D requirements listed in Table 5, two watersheds within North Middleton Township, and Alexanders Spring Run, have impairments regulated by PAG-13 General Permit, Appendix E (nutrients and/or sediment in stormwater discharges to impaired waterways). Appendix E siltation impairments require a minimum 10-percent reduction in sediment load. The pollutant load reduction requirements in pounds per year for Appendix E watersheds are shown in Table 6. The pollutant load reduction requirements listed below take into account adjustments to baseline loading from the parsed areas and existing BMPs discussed in Section D. The planning areas associated with each of these impaired waters are shown on the Planning Area Map (Appendix B). Table 6: Required Pollutant Load Reduction Goals PRP Planning Areas Planning Area UA Required Load Reduction TSS (lbs/yr) PRP 2, ,717 Alexanders Spring Run PRP ,535 As stated previously, the load reduction requirements for each impaired watershed planning areas are included as a portion of, and not in addition to, the CBPRP pollutant load reduction. Of the total CBPRP planning area required sediment load reduction (175,623 lbs/yr), at least 78-percent (137,717 lbs/yr) must be achieved within the planning area, and 7-percent (12,535 lb/yr) must be achieved within the Alexanders Spring Run planning area. The remaining 15-percent (25,371 lb/yr) may be achieved anywhere within the CBPRP planning area. 10 PADEP - PRP Instructions, Document # 3800-PM-BCW0100k (rev. 3/2017)

12 Page 10 E.2 Proposed BMPs The following section outlines the BMP implementation strategy developed to achieve the required pollutant load reduction goals stated in Section E.1. The proposed BMPs were determined through discussions with the public works employees and municipal staff, in-field site assessments, and public outreach meetings. A summary of the type and scale of BMP projects included in the pollutant reduction strategy is listed in Tables 6A and 6B. The pollutant loading reductions for each proposed BMP were calculated in terms of pounds per year using the simplified method and PADEP s standard BMP Effectiveness Values 11. Complete calculations for the anticipated pollutant load reductions for each BMPs listed below is provided in Appendix E. Table 6A: North Middleton BMP Strategy Summary Municipal Property Projects Project Site Regal View Drive (Old Landfill) BMP ID BMP-1 BMP Type Riparian Buffer Village Park BMP-2 Bioretention Township Municipal Bldg. Creekview Park BMP-3 BMP-4 BMP-5 BMP-6 Bioretention Bioretention Upgrade (Additional treatment for existing drainage area) Bioretention (New Drainage Area routed to BMP) Stream/Swale Restoration (350 ft) Riparian Buffer (1,000 ft) Planning Area Size (acre) Drainage Area Load Reduction TSS (lbs/yr) , , , ,831 n/a n/a 15, ,329 Total 69, PADEP Document 3899-PM-BCW0100M, NPDES Stormwater Discharges from Small MS4s, BMP Effectiveness Values (5/2015)

13 Page 11 Table 6B: North Middleton BMP Strategy Summary Private Property Projects Project Site Distribution Drive Warehouses Oriole Drive Virginia Avenue Jenni Lane Crain Drive Regal View Drive BMP ID BMP-7 BMP-8 BMP-9A BMP-9B BMP-9C BMP-10A BMP-10B BMP-10C BMP-11 BMP-12 BMP Type Basin Retrofits Basin Retrofit Outfall Repair & Stabilization (100 ft) Outfall Repair & Stabilization (200 ft) Stream Restoration (400 ft) Outfall Repair & Stabilization (100 ft) Outfall Repair & Stabilization (100 ft) Obstruction Removal & Stream Restoration (300 ft) Swale Restoration (300 ft) Basin Retrofit Planning Area Alexanders Spring Run Size (acre) Drainage Area Load Reduction TSS (lbs/yr) , ,066 n/a n/a 4,488 n/a n/a 8,976 n/a n/a 17,952 n/a n/a 4,488 n/a n/a 4,488 n/a n/a 13,464 n/a n/a 13, ,812 Total 106,327 E.3 BMP Project Location A summary of the estimated pollutant load reductions from the proposed BMPs within each planning area is shown below in Table 7. As the watershed has the greatest amount of UA and associated pollutant load, the majority of the proposed BMP projects are located within this planning area. The Alexanders Spring Run planning area is smaller in terms of UA and associated pollutant load, and therefore only one proposed BMP project is required in this planning area to meet to required pollutant load reduction. Table 7: Proposed BMPS by Planning Area Planning Area No. of Projects Estimated TSS Reduction from Proposed BMPs (lbs/yr) TSS Reduction Required (lbs/yr) % of Total Reduction , ,717 89% Alexanders Spring Run 1 19,129 12,535 11% CBPRP (Total) , , %

14 Page 12 E.4 Proposed BMP Descriptions Unless otherwise noted, the proposed BMP projects described below have not been fully designed. The following projects descriptions are conceptual and intended for planning and implementation purposes only. When designed, all proposed BMP projects will be in accordance with the Pennsylvania BMP Manual, all local ordinances and regulations as well as any applicable DEP guidance documents. Proposed projects have been evaluated in terms of preliminary feasibility and estimated pollutant load reductions in order to meet the goals of this plan. It is anticipated that during plan implementation, proposed BMP projects may change or be replaced as additional information becomes available. Details for each proposed project will be documented in the Annual Status Reports. Regal View Drive (Old Landfill) Riparian Buffer - The Township owns a large parcel of land north of the Conodoguinet Creek to the south of Regal View Drive. This property is a capped landfill and therefore development options for the property are limited. A stream channel runs along the northern property line and conveys stormwater from the residential development located to the north of property around the perimeter of the landfill. The stream channel is rock lined and is not in need of further stabilization, however there is only minimal existing vegetation around the channel. This project proposed to install a 35-foot wide riparian buffer along approximately 1,200 feet of the stream. The buffer planting will consist of a diverse selection of native trees and shrubs that will provide additional stabilization for the streambank and protect against thermal impacts to the stream. Village Park Bioretention - The wood chip material around the base of the playground is frequently washed out during heavy rain events. The proposed bioretention facility will be situated along the north end of the parking lot where it will intercept stormwater runoff before it can impact the playground area. It is anticipated that the design of this BMP will include an excavated shallow surface depression with amended soils and specially selected native vegetation to treat and capture runoff. The vegetation will serve to filter (water quality) and transpire (water quantity) runoff. The bioretention facility plants will take up pollutants, the root systems can enhance infiltration, and the amended soil medium will both filter out pollutants and allow for storage and infiltration of stormwater runoff. Municipal Building Basin Upgrade and Stream Restoration - A 0.8-acre reconstructed wetland area is located at the corner of Spring Road and Clearwater Drive adjacent to the Township Municipal building. Currently this BMP only treats stormwater runoff from a portion of the municipal parking lot. Stormwater runoff from a large drainage area to the south of the municipal building is collected and conveyed by the MS4 to a swale that runs alongside Clearwater Drive. The proposed basin upgrade will include restoration and realignment of the approximately 350-foot swale through the existing wetland BMP. This will allow the existing BMP to receive stormwater from a much larger drainage area. Pockets of amended soils and additional vegetation will be added to the existing BMP to increase infiltration and provide a more naturalized appearance. Stormwater runoff from the Fire Station to the east of the Township Municipal building drains to a large grass depression along Clearwater Drive. This area functions as a stormwater detention facility, but currently provides little benefit in terms of stormwater quality benefit. The proposed upgrade for this basin will include grading and the addition of bioretention pockets with amended soil and bioretention plantings to promote stormwater infiltration.

15 Page 13 Creekview Park Riparian Buffer - Creekview Park is a 10-acre neighborhood park located along the Conodoguinet Creek. There is 0.5-mile gravel loop trail around the perimeter of the park, and currently there is minimal buffer areas between the mowed lawn of the park and the creek. This project proposes to install multiple plantings along the creek to establish a 35-foot wide riparian buffer. This buffer will slow the velocity of stormwater runoff, thereby helping to maintain a stable streambank by allowing runoff to infiltrate and recharge groundwater. Distribution Drive Basin Retrofit - The Alexanders Spring Run watershed is located in the southwestern corner of the Township in the commercial development area. The majority of the northern portion of the Alexanders Spring Run watershed (north of the Turnpike) contains no MS4 infrastructure and has therefore been parsed from the CBPRP and PRP planning areas. Alexanders Spring Run is small stream with minimal water volume. A site visit determined that the presence of sinkholes is likely reason for the decreased stream volume. Previous portions of the stream have been restored during the rehabilitation of the Meadowbrook Road and Dyarman Road bridges. However, due to the minimal volume of water currently conveyed by this stream, it was determined that the implementation of additional stream restoration BMPs would be impractical in this watershed. There are several large warehouses located within the Alexanders Spring Run Watershed, to the east of Alexanders Spring Run. The stormwater basins associated with these warehouses provide stormwater volume control, but do not currently provide any stormwater quality benefit. This project proposes to upgrade two of the existing detention basins to include bioretention features. The detention basin retrofits will include the removal of existing concrete low-flow channels, installation of pockets of amended soils to promote infiltration, and the addition of bioretention plantings. The Township will coordinate with private property owners for the design and development of this project. Oriole Drive Basin Retrofit - The existing basin on Oriole Drive near the intersection with Falcon Drive provides stormwater volume control, but currently provided minimal stormwater quality benefit. The basin is maintained as mowed grass. Retrofit of the basin to improve water quality will include the addition of pockets of amended soils to promote infiltration and riparian plantings. Virginia Ave Stream Restoration and Outfall Stabilizations - A swale located between Virginia Ave and Pheasant Drive North receives stormwater runoff from two outfalls: a 36-inch concrete outfall from Douglas Drive and a 30-inch corrugated metal pipe from Pheasant Drive North. Stormwater from these two outfalls flows along an approximately 1,400-foot swale to the Conodoguinet Creek. Both outfalls are eroded and in poor condition. The drainage path from the Virginia Ave outfall was at one time paved with asphalt but has since eroded and broken into multiple pieces. The project will remove the broken pieces of asphalt, install more permanent outfall stabilization to prevent erosion and create a more naturalized stream channel. The outfall from Pheasant Drive North will also be repaired and stabilized to prevent erosion. Additionally, the drainage pathway between the two outfalls will be restored.

16 Page 14 The outfalls/drainage channels have existing vegetative buffers. During the design phase of the project it will be determined if additional plantings are needed to supplement the existing buffer. The stream stabilization design will be in accordance with the DEP stream restoration guidance. 12 Jenni Lane Stream Restoration and Outfall Stabilization - Stormwater collected by the MS4 in the vicinity of Jenni Lane is collected and conveyed by the MS4 to a 36-inch corrugated metal outfall across Sterretts Gap Ave. This outfall is partially crushed and is in need of repair. This project will repair the outfall and provide stabilization to protect against future erosion. Stormwater from the outfall flows into a swale that flows west towards the Conodoguinet Creek, however approximately 200 feet from the outfall, the swale is obstructed by a stone building foundation in the middle of the channel. This project proposes to remove the obstruction and stabilize the 200-foot section of streambank. The drainage channel has existing vegetative buffers, however during the design phase of the project it will be determined if additional plantings are needed to supplement the existing buffer. The stream stabilization design will be in accordance with the DEP stream restoration guidance. Crain Drive Swale Restoration - A swale that flows parallel to Spring Road and discharges to the Conodoguinet Creek along Crain drive is in poor condition and in need of repair. This swale is connected to the Township MS4 and receives stormwater from a large drainage area to the south of the project site. The Township plans to stabilize the swale to repair existing erosion areas (approximately 300 feet) and prevent further erosion issues as well as and protect the adjacent properties. When designed and implemented, swale stabilization will be in accordance with the DEP stream restoration guidance. Regal View Drive Basin Retrofit - The existing basin on Regal View Drive near the intersection with Cottonwood Drive provides stormwater volume control, but currently provided minimal stormwater quality benefit. The basin is maintained as mowed grass. Retrofit of the basin to improve water quality will include the addition of pockets of amended soils to promote infiltration and riparian plantings. 12 PADEP Considerations of Stream Restoration Projects in Pennsylvania for Eligibility as an MS4 Best Management Practice (June 2017).

17 Page 15 Section F: Funding Mechanisms Funding for the design and construction of the BMPs proposed herein will be funding through variety of sources including the Township s General Fund, available grants, and public donation of materials and manpower.

18 Page 16 Section G: BMP Operations and Maintenance (O&M) Once implemented, the BMPs outlined in this plan will be operated and maintained by the Township to ensure that they continue to produce the expected pollutant reductions. The O&M activities will be reported in the Annual MS4 Status Reports submitted in accordance with the General Permit. The O&M activities and schedule for each BMP will be developed during the design phase. A general summary of the O&M activities involved with each BMP type and the frequency at which O&M activities will occur are as follows: Table 8: Operations and Maintenance Schedule BMP Responsible Party O&M Activities Frequency Stream/ Swale Restoration Riparian Buffer Bioretention / Basin Retrofit Municipal Staff Municipal Staff Municipal Staff Inspection Revegetation (replanting, replacement of dead, or impaired vegetation) Repairs to streambank armoring structures Removal of nuisance aquatic vegetation/ woody debris Inspection Watering Mowing/Weed Control Invasive Removal Inspection Pruning/Weeding Cut down Perennial Planting/ Detritus Removal Re-spread Mulch Watering Twice per year and as needed after major storm events As needed As needed As needed Twice per year Regularly during the first growing season Twice per growing season As needed Twice per year Annually (or as needed while vegetation is being established) Annually (at end of growing season) Every 2-3 years (or as needed when erosion is evident) As needed during periods of extended drought

19 Page 17 APPENDIX A Public Participation Documentation

20 Page 18 Page to be replaced with the following (as applicable): Copy of the public notice from newspaper Copies of all public comments and the responses issued to each comment Meeting minutes for the meeting at which the PRPs were presented A record of the incorporated changes as a result of public comment

21 Page 19 APPENDIX B Mapping

22 Middle Sherman Creek Watershed Lower Sherman Creek Watershed ENOLA RD WAGNER DR Meetinghouse Run WAGGONERS GAP RD CRANES GAP RD - Conodoguinet Creek Watershed Direct Discharge BMP-1!O!O BMP-12!O BMP-8 MIDDLESEX DR SPRING RD Conodoguinet Creek!O BMP-6 RESERVOIR DR CRAIN DR BMP-11!O!O!O!O BMP-4 Ex-1!O BMP-3 Direct Discharge MCCLURES GAP RD Direct Discharge BMP-9C!O!O BMP-9A BMP-9B WAGNER ST!O Ex-3 LONGS GAP RD!O BMP-10C BMP-10B!O!O STERRETS GAP DR BMP-10A!O!O!O BMP-2 Ex-2A Ex-2B CAVALRY RD Letort Spring Run Watershed K ST PA National Guard Armory EX-6!O!O EX-5 EAST/WEST TURNPIKE!O Ex-4 HARRISBURG PK Alexanders Spring Creek!O BMP-7 Letort Spring Run POST RD Alexanders Spring Creek Watershed NEWVILLE RD ORANGE ST CLAREMONT RD US Army War College CARLTON AV TRINDLE RD P:\0007\000723_0425\GIS\Projects\NorthMiddleton_CBPRP_PlanningArea_24x36port.mxd [ 1, ,200 Feet Mapping derived from data provided by North Middleton Township, PennDOT, and USGS. 7/20/2017 PM: EGL GIS: BLS QA: HSH R East Park Drive Harrisburg, PA [phone] [fax] Proposed BMP!O Existing BMP UTpo Storm Observation Point $1 Storm Clean Out Storm Outfall Storm Fitting Storm Inlet Storm Manhole Storm Culvert Storm Gravity Main Storm Open Drain Storm Virtual Drainline Storm Basin Local Roads State Road Parsed Areas Municipal Boundary Urbanized Area (2010) CBPRP Planning Area North Middleton Township Cumberland County, Pennsylvania

23 LOWER FRANKFORD TOWNSHIP WEST PENNSBORO TOWNSHIP NORTH MIDDLETON TOWNSHIP NORTH MIDDLETON TOWNSHIP CARLISLE BOROUGH SPRING SPRING CARROLL CARROLL NORTH MIDDLETON TOWNSHIP ENOLA RD W ertz Run WAGGONERS GAP RD Meetinghouse Run SPRING RD MCCLURES GAP RD Alexanders Spring Creek WEST PENNSBORO TOWNSHIP NEWVILLE RD Conodoguinet C reek I 76 B ST CARLISLE SPRINGS RD Letort Spring CAVALRY RD Run HARRISBURG PIKE NORTH MIDDLETON TOWNSHIP MIDDLESEX TOWNSHIP ALLEN RD RITNER HWY COLLEGE ST HIGH ST HANOVER ST NORTH ST CLAREMONT RD P:\0007\000723_0425\GIS\Projects\LandUseMap_11x17port.mxd [ DICKINSON TOWNSHIP CARLISLE BOROUGH 2, ,500 Feet Mapping derived from data provided by Cumberland County, Perry County, USGS, US Census, and MRLC. 5/5/2017 PM: EGL GIS: BLS/ HMG QA: HSH R East Park Drive Harrisburg, PA [phone] [fax] Road Municipal Boundary Open Water Developed, Open Space Developed, Low Intensity WALNUT BOTTOM RD Developed, Medium Intensity Developed, High Intensity Deciduous Forest Evergreen Forest Mixed Forest WILLOW ST Shrub/Scrub Grassland/Herbaceous Pasture/Hay Cultivated Crops Woody Wetlands Emergent Herbaceous Wetlands Urban Areas (2010) CARLISLE BOROUGH YORK RD SOUTH MIDDLETON TOWNSHIP TRINDLE RD Land Use Map North Middleton Township Cumberland County, Pennsylvania I 81

24 Page 22 APPENDIX C PADEP Municipal MS4 Requirements Table

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27 Page 25 APPENDIX D Existing Pollutant Loading Calculations

28 Page 26 Appendix D Table 1A: Existing Pollutant Load Calculation Summary, CBPRP Planning Area Planning Area Loading Rate** Urbanized Area* Total TSS (lbs/ac/yr) Load TSS UA % % Imperv. Perv. Imperv. Perv. Imperv. Perv. (lbs/yr) CBPRP 4,769 23% 77% 1, , ,392,235 Parsed (Military Properties) % 77% ,618 Parsed (PennDOT Roadways) 133 n/a n/a ,678 Parsed (Direct Drainage) 1,734 23% 77% , ,233,437 Adjusted Baseline Total 2,628 1,783,502 *PADEP - Statewide MS4 Land Cover Estimates **PADEP PRP Instructions - Attachment B, Developed Land Loading Rates for PA Counties Appendix D Table 1B: Existing Pollutant Load Calculation Summary, PRP Planning Area Planning Area Loading Rate** Urbanized Area* Total TSS (lbs/ac/yr) Load TSS UA % % Imperv. Perv. Imperv. Perv. Imperv. Perv. (lbs/yr) PRP 3,842 23% 77% , ,732,980 Parsed (PennDOT Roadways) 102 n/a n/a ,819 Parsed (Direct Drainage) 1,694 23% 77% ,204,699 Adjusted Baseline Total 2,046 1,395,462 *PADEP - Statewide MS4 Land Cover Estimates **PADEP PRP Instructions - Attachment B, Developed Land Loading Rates for PA Counties Appendix D Table 1C: Existing Pollutant Load Calculation Summary, Alexander Spring Run PRP Planning Area Planning Area Loading Rate** Urbanized Area* Total TSS (lbs/ac/yr) Load TSS UA % % Imperv. Perv. Imperv. Perv. (lbs/yr) Imperv. Perv. Alexander Spring Run PRP % 77% ,154 Parsed (PennDOT Roadways) 27 n/a n/a ,719 Parsed (Direct Drainage) 41 23% 77% ,107 Adjusted Baseline Total ,328 *PADEP - Statewide MS4 Land Cover Estimates **PADEP PRP Instructions - Attachment B, Developed Land Loading Rates for PA Counties

29 Page 27 Appendix D Table 2A: Parsed Area Load Reductions State Roadways (PennDOT), CBPRP Planning Area Parsed Area (Roadway Name) Urbanized Area* Loading Rate** TSS (lbs/ac/yr) Total Load TSS (lb/yr) Length Width (ft) Width (ft) Imperv. Perv. (ft) Imperv. Perv. Imperv. Perv PA Turnpike 23, , , Waggoners Gap Rd 1, , , Spring Rd 12, , , N Hanover St/ Harrisburg Pike 4, , ,015.3 Calvary Rd 4, , ,989.2 McClures Gap Rd 3, , ,622.8 Crain Dr 1, , ,586.4 Reservoir Rd 3, , ,824.9 Stenettes Gap Ave 2, , ,392.6 Post Rd 1, , , Allen Rd , Newville Rd 10, , ,756.2 Total 180,678 *PADEP - Statewide MS4 Land Cover Estimates **PADEP PRP Instructions - Attachment B, Developed Land Loading Rates for PA Counties Appendix D Table 2B: Parsed Area Load Reductions State Roadways (PennDOT), PRP Planning Area Loading Rate** Urbanized Area* TSS (lbs/ac/yr) Parsed Area (Roadway Name) Length (ft) Width (ft) Imperv. Width (ft) Perv. Imperv. Perv. Imperv. Perv. Total Load TSS (lb/yr) 76 - PA Turnpike 19, , , Waggoners Gap Rd 1, , , Spring Rd 12, , ,054.5 Calvary Rd 2, , ,502.9 McClure's Gap Rd 3, , ,622.8 Crain Dr 1, , ,586.4 Reservoir Rd 3, , ,824.9 Stenettes Gap Ave 2, , ,392.6 Post Rd 1, , ,350.4 Total 132,819 *PADEP - Statewide MS4 Land Cover Estimates **PADEP PRP Instructions - Attachment B, Developed Land Loading Rates for PA Counties

30 Page 28 Appendix D Table 2C: Parsed Area Load Reductions State Roadways (PennDOT), Alexander Spring Run PRP Planning Area Parsed Area (Roadway Name) Urbanized Area* Loading Rate** TSS (lbs/ac/yr) Total Load TSS (lb/yr) Length Width (ft) Width (ft) Imperv. Perv. (ft) Imperv. Perv. Imperv. Perv PA Turnpike 3, , , Newville Rd 4, , , Allen Rd , ,644.1 Total 39,719 *PADEP - Statewide MS4 Land Cover Estimates **PADEP PRP Instructions - Attachment B, Developed Land Loading Rates for PA Counties Appendix D Table 3: Parsed Area Load Reductions Military Installation, CBPRP Planning Area Loading Rate** Urbanized Area* TSS (lbs/ac/yr) Total Load TSS (lbs/yr) Parsed Area UA % % Imperv. Perv. Imperv. Perv. Imperv. Perv. PA Nat l Guard Armory 40 23% 77% , ,453.0 US Army War College % 77% , ,659.2 Total ,618 *PADEP - Statewide MS4 Land Cover Estimates **PADEP PRP Instructions - Attachment B, Developed Land Loading Rates for PA Counties Appendix D Table 4A: Parsed Area Load Reductions Direct Discharge Areas, CBPRP Planning Area Loading Rate** Urbanized Area* TSS (lbs/ac/yr) Parsed Area UA % Imperv. % Perv. Imperv. Perv. Imperv. Perv. Total Load TSS (lbs/yr) DD - Area 1 1, % 77% , , ,160,825 DD- Area % 77% , ,982 Total 1, ,233,807 *PADEP - Statewide MS4 Land Cover Estimates **PADEP PRP Instructions - Attachment B, Developed Land Loading Rates for PA Counties

31 Page 29 Appendix D Table 4B: Parsed Area Load Reductions Direct Discharge Areas, Planning Area Loading Rate** Urbanized Area* TSS (lbs/ac/yr) Parsed Area UA % Imperv. % Perv. Imperv. Perv. Imperv. Perv. Total Load TSS (lbs/yr) DD-Area 1 1, % 77% , , ,131,717 DD-Area % 77% , ,982 Total 1, ,204,699 *PADEP - Statewide MS4 Land Cover Estimates **PADEP PRP Instructions - Attachment B, Developed Land Loading Rates for PA Counties Appendix D Table 4C: Parsed Area Load Reductions Direct Discharge Areas, Alexander Spring Run Planning Area Loading Rate** Urbanized Area* TSS (lbs/ac/yr) Parsed Area UA % Imperv. % Perv. Imperv. Perv. Imperv. Perv. Total Load TSS (lbs/yr) DD-Area % 77% , ,107 Total ,107 *PADEP - Statewide MS4 Land Cover Estimates **PADEP PRP Instructions - Attachment B, Developed Land Loading Rates for PA Counties

32 Page 30 Appendix D Table 5: Baseload Reduction Documentation, Existing BMPs by Planning Area BMP ID Ex-1 Ex-2A BMP Type Location Lat Long Planning Area Constructed Wetland Constructed Wetland Municipal Bldg. (Spring Rd) Village Park (by Road) **ADEP - Statewide MS4 Land Cover Estimates **PADEP PRP Instructions - Attachment B, Developed Land Loading Rates for PA Counties ***Standard Effectiveness Values, PADEP Approx. Drainage Area Drainage Area Characteristics* % Imperv. % Perv. Imperv. Perv. Loading Rate TSS (lbs/yr)** Imperv. Perv. Total Load TSS (lb/yr) BMP Effectiveness *** Load Reduction TSS (lb/yr) % 77% , ,130 60% 1, % 77% , ,201 60% 1,921 Ex-2B Extended Detention Village Park Basin (by Parking Lot) % 77% , ,010 60% 606 Ex-3 Infiltration Trench Crestview Elementary School % 77% , ,063 90% 1,857 Ex-4 Detention Basin Bellaire Elementary School % 77% , ,059 60% 12,035 Ex-5 Stream Restoration Alexanders Dyarman Bridge (100 ft) Spring Run n/a n/a n//a n/a n/a n/a n/a n/a lbs/ft 4,488 Ex-6 Stream Restoration Alexanders Meadowbrook Bridge (100 ft) Spring Run n/a n/a n/a n/a n/a n/a n/a n/a lbs/ft 4,488 Total 27,273

33 Page 31 APPENDIX E Proposed BMP Pollutant Load Reduction Calculations

34 Page 32 Appendix E Table 1: Proposed BMPs Site BMP ID BMP Type Lat Long Regal View Drive (Old Landfill) BMP-1 Riparian Buffer Village Park BMP-2 Bioretention Township Municipal Bldg. Creekview Park Distribution Drive Warehouses Planning Area Size (acre) / Length (ft) Drainage Area Drainage Area Characteristics* % Imperv. % Perv. Imperv. Perv. Loading Rate TSS (lbs/ys)** Imperv. Perv. Total Load TSS (lb/yr) BMP Effectiveness *** Load Reduction TSS (lb/yr) 1,200 ft % 77% , ,574 50% 8, ac % 77% , % 736 BMP-3 Bioretention ac 10 23% 77% , ,113 90% 6,402 Bioretention Upgrade (Additional treatment % 77% , ,130 90% 1,127 existing drainage area) BMP ac Bioretention (New drainage area % 77% , ,256 90% 21,831 routed to BMP) BMP-5 Stream/swale Restoration ft n/a n/a n/a n/a n/a n/a n/a n/a ,708 BMP-6 Riparian Buffer ,000 ft % 77% , ,658 50% 15,329 BMP-7 Basin Retrofits Alexanders 1.6 ac % 77% ,616 90% 19,129 Spring Run 0.15 ac 14 23% 77% % 8,066 BMP-9A Outfall Repair & ft n/a n/a n/a n/a n/a n/a n/a n/a lb/ft 4,488 Oriole Drive BMP-8 Basin Retrofit Virginia Avenue Jenni Lane Crain Drive Regal View Drive BMP-9B Stabilization Outfall Repair & Stabilization BMP-9C Stream Restoration BMP-10A BMP-10B Outfall Repair & Stabilization Outfall Repair & Stabilization BMP-10C Stream Restoration BMP-11 Stream/Swale Restoration BMP-12 Basin Retrofit ft n/a n/a n/a n/a n/a n/a n/a n/a lb/ft 8, ft n/a n/a n/a n/a n/a n/a n/a n/a lb/ft 17, ft n/a n/a n/a n/a n/a n/a n/a n/a lb/ft 4, ft n/a n/a n/a n/a n/a n/a n/a n/a lb/ft 4, ft n/a n/a n/a n/a n/a n/a n/a n/a lb/ft 13, ft n/a n/a n/a n/a n/a n/a n/a n/a lb/ft 13, ac % 77% ,582 90% 11,812 TOTAL 175,747 *PADEP - Statewide MS4 Land Cover Estimates **PADEP PRP Instructions - Attachment B, Developed Land Loading Rates for PA Counties ***Standard Effectiveness Values, PADEP; EPA Chesapeake Bay Model 5.3 (To calculate the pollutant load reductions associated with a basin retrofit, in accordance with the Chesapeake Bay Model 5.3, a 10% pollutant load reduction was assumed for existing, pre-retrofit, detention basins. As the basin retrofit will upgrade the existing detention basin into a bioretention basin, the bioretention BMP efficiency of 90% was used the calculate the pollutant load reduction for the basin, however this pollutant load efficiency was only applied to that portion of the runoff entering into the basin that is not already receiving treatment.)