ACT 167 STORMWATER MANAGEMENT ORDINANCE ORDINANCE NO. 659 MUNICIPALITY OF BOROUGH OF RIDGWAY ELK COUNTY, PENNSYLVANIA Adopted at a Public Meeting Held on March 21,2011 Page No. 1 1 1 1 2 2 2 2 3 4 14 14 16 20 22 22 23 27 31 31 35 35 36 36 36 37 37 37 37 38 38 38 39 39 Article I- General Provisions Section 101. Short Title Section 102. Statement of Findings Section 103. Purpose Section 104. Statutory Authority Section 105. Applicability Section 106. Repealer Section 107. Severability Section 108. Compatibility with Other Ordinance Requirements Article II- Definitions Article III- Stormwater Management Standards Section 301. General Requirements Section 302. Exemptions Section 303. Waivers Section 304. Volume Controls Section 305. Rate Controls Section 306. Calculation Methods Section 307. Other Requirements Article IV- SWM Site Plan and Report Requirements Section 401. Plan and Report Contents Section 402. Plan Submission Section 403. Plan Review Section 404. Modification of Plans Section 405. Resubmission of Disapproved SWM Site Plans Section 406. Record Drawings and Final Inspection Article V-Operation and Maintenance Section 501. Responsibilities Section 502. Operation and Maintenance Agreements Section 503. Financial Guarantee Section 501A. Schedule of Inspections Section 502A. Right-of-Entry Article VI-Fees and Expenses Section 601. General Article V-A Inspections Article VIl-Prohibitions 40 40 40 40 41 41 41 41 41 42 42 43 Section 701. Prohibited Discharges and Connections Section 702. Roof Drains Section 703. Alteration of BMPS Article Vll-Enforcements and Penalties Section 801. Right-of-Entry Section 802. Inspection Section 803. Enforcement Section 804. Suspensions andl Revocation Section 805. Penalties Section 806. Appeals Article IX- References Appendix A: Low Impact Development Practices Appendix B: Site Conditions Suitable for Infiltration BMPS for Infiltration BMPS for Rate Control BMPS for Evapotranspiration Appendix C: Operation and Maintenance Agreement, Stormwater Best Management Practices Appendix D: Rational Formula Runoff Coefficients Appendix E: Release Rate District Map Appendix F: Small Project SWMI Plan Application and' Worksheets Appendix G: Disconnected Impervious Areas Appendix H: Fee Reimbursement Agreement Appendix :: Additional Ordinance and Technical Guidelines ARTICLEI-GENERAL PROVISIONS Section 101. Short Title This Ordinance shall be known and may be cited as the Borough of Ridgway Stormwater Management Ordinance." Section 102. Statement of Findings The governing body of the Municipality finds that: A. Inadequate management of accelerated runoff of Stormwater resulting from development throughout a watershed increases flows and velocities, contributes to erosion and sedimentation, overtaxes the carrying capacity of streams and storm sewers, greatly increases the cost of public facilities to carry and control Stormwater, undermines flood plain management and flood control efforts in downstream communities, reduces groundwater recharge, threatens public health and A comprehensive program of Stormwater management, including reasonable regulation of development and activities causing accelerated runoff, isf fundamental to the publicl health, safety and welfare and the protection of people oft the Commonwealth, their resources and the Stormwater is an important water resource, which provides groundwater recharge for water supplies and base flow of streams, which protects and maintains surface water quality. Federal and state regulations require certain Municipalities to implement a program of Stormwater controls. These Municipalities are required to obtain a permit for Stormwater. discharges from their separate storm sewer systems under the National Pollutant Discharge Elimination System safety, and increases non-point source pollution of water resources. B. environment. C. D. (NPDES). Section 103. Purpose The purpose oft this Ordinance is to promote health, safety, and welfare within the Municipality and its watershed by minimizing the harms and maximizing the benefits described in Section 102 of this Ordinance, through provisions designed to: A. Meet legal water quality requirements under state law, including regulations at 25Pa. Code Chapter 93 toy protect, maintain, reclaim and restore the existing and designated uses. B. Preserve the natural drainage systems as much as possible. 1 C. D. E. F. G. H. Manage Stormwater runoff close to the source. Provide the minimum procedures and performance standards for Stormwater planning and Maintain groundwater recharge, to prevent degradation of surface and groundwater quality management. and to otherwise protect water resources. Prevent scour and erosion of stream banks and streambeds. Provide proper operations and maintenance of all permanent Stormwater Management Best Management Practices BMPs)implemented within the Municipality. Provide standards to meet NPDES permit requirements. Section 104. Statutory Authority A. Primary Authority: The Municipality is empowered to regulate these activities by the authority of the Act of October 4, 1978, P.L. 864 (Act 167), 32P.S. Section 680.1, ets seq., as amended, the "Stormwater Management. Act" and the (appropriate Municipal code). B. Secondary Authority: The Municipality is empowered to regulate land use activities that affect runoff by the authority of the Act of July 31, 1968, P.L. 805, No. 247, The Pennsylvania Municipalities Planning Code, as amended. Section 105. Applicability Ail Reguiated Activities and all activities that may affect Stormwater runoff, including land development or earth disturbance, are subject to regulation by this Ordinance. Section 106. Repealer Any other ordinance provision(s) or regulation of the Municipality inconsistent with any of the provisions of this Ordinance is hereby repealed to the extent of the inconsistency only. Section 107. Severability In the event that a court of competent jurisdiction declares any section or provision oft this Ordinance invalid, such decision shall not affect the validity of any of the remaining provisions of this Ordinance. 2 Section 108. Compatibility with Other Ordinance Requirements Approvals issued and actions taken under this Ordinance do not relieve the Applicant of the responsibility tos secure required permits or approvals for activities regulated by any other code, law, regulation or ordinance. 3 ARTCLEI-DEFNTIONS Fort the purposes oft this Ordinance, certain terms and words used herein shall be interpreted as follows: A. Words usedi in the present tense include the future tense; the singular number includes the plural, and the plural number includes the singular,; words ofr masculine gender include feminine gender; and words off feminine gender include masculine gender. The word "includes" or' 'including" shall not limit the term to the specific example buti is intended to extend its meaning to all otheri instances ofl like kind and character. C. The words "shal" and' must" are mandatory; the words "may" and' "should" are B. permissive. D. The words "used or occupied" include the words intended, designed, maintained, or arranged to be used or occupied." Accelerated Erosion The removal of the surface of the land through the combined action ofr man's activity and the natural processes of ar rate greater than would occur because of the natural process alone. Agricultural Activity The work ofp producing crops including tillage, land clearing, plowing, disking, harrowing, planting, harvesting crops, or pasturing and raising ofl livestock and installation of conservation measures. Construction of new buildings ori impervious area is not considered an Agricultural Activity. Alteration As applied to land, a change in topography because of the moving of soil and rock from one location or position to another; also the changing of surface conditions by causing the surface to be moreor Applicant Al landowner, developer or other person who has filed an application for approval to engage in Bank full - The channel at the top-of-bank or point where water begins to overflow onto ai floodplain. Base Flow- - Portion of stream discharge derived from groundwater; the sustained discharge that does not result from direct runoff or from water diversions, reservoir releases, piped discharges, or other human Bioretention - A Stormwater retention areai that utilizes woody and herbaceous plants and soils to remove BMP (Best Management Practice) Activities, facilities, designs, measures or procedures used to manage Stormwater impacts from Regulated Activities, to meet State Water Quality Requirements, to promote groundwater recharge and to otherwise meet the purposes of this Ordinance. BMPS include but are not limited toi infiltration, filter strips, lowi impact design, bio-retention, wet ponds, permeable paving, grassed swales, forested buffers, sand filters and detention basins. Structural SWM BMPs are permanent Carbonate Bedrock (Areas) - Rock consisting chiefly of carbonate minerals, such as limestone and dolomite; specifically. a sedimentary rock composed of more than 50% by weight of carbonate minerals that less impervious; land disturbance. any Regulated Earth Disturbance activity at aj project site in the Municipality. activities. pollutants before infiltration occurs. appurtenances tot the project site. underlies soil or other unconsolidated, superficial material. 4 Channel A drainage element in which Stormwater flows with an open surface. Open channels include, but shall not be limited to, natural and man-made drainage ways, swales, streams, ditches, canals, and Channel Erosion The widening, deepening, and headward cutting of small channels and waterways, pipes flowing partly full. caused by Stormwater runoff or bank full flows. Cistern -A Anu underground reservoir or tank for storing rainwater. Conservation District-A A conservation district, as defined in section 3(c) of the Conservation District Law (3P.S.S8 851(c), which has the authority under a delegation agreement executed with the Department to administer and enforce all or aj portion oft the erosion and sediment control program in this Commonwealth. Culvert A structure with appurtenant works, which carries water under or through an embankment or fill. Dam An artificial barrier, together with its appurtenant works, constructed for the purpose ofi impounding or storing water or another fluid or semi fluid, ora an refuse bank, fill or structure for highway, railroad or other purposes which does or mayi impound water or another fluid or semi fluid. Delineation - The process of determining a wetland's physical boundaries. Designee The agent oft the Elk County Planning Commission, Elk County Conservation District andlor agent oft the governing body involved with the administration, review or enforcement of any provisions of Design Storm The magnitude and temporal distribution of precipitation from a storm event measured in probability of occurrence (e.g. a 5-year storm) and duration (e.g. 24-hours), used in the design and Detention the volume ofr runoff that is captured and released into the Waters of this Commonwealth ata Detention Basin An impoundment designed to collect and attenuate Stormwater peak runoff by temporarily storing the runoff and releasing it at a predetermined rate. Detention basins are designed to drain completely shortly after any given rainfall event and are dry until the next rainfall event. PAI DEP-7 The Pennsylvania Department of Environmental Protection. Development See Earth Disturbance Activity." The term includes redevelopment. this ordinance by contract or memorandum of understanding. evaluation of Stormwater management systems. (See Return Period) controlled rate. Discharge - Tor release water from a project, site, aquifer, drainage basin or other point ofi interest (verb); The rate and volume of flow of water such as in a stream, generally expressed in cubic feet per second (volume per unit oft time) (noun). See also Peak Discharge. Discharge Point-T The point to which Stormwater flows. Disconnected Impervious Area (DIA)- - Ani impervious or impermeable surface that is disconnected from any stormwater drainage or conveyance system andi is redirected or directed to a pervious area, which allows fori infiltration, filtration, and increased time of concentration as specified in Appendix G, Disturbed Area - An un-stabilized land area where an earth disturbance activity is occurring or has Disconnected Impervious Area. occurred. Ditch - (See Channel). 5 Down Slope Property Line - That portion of the property line of the lot, tract, or parcels of land being Drainage Easement - A right granted by a landowner to a grantee, allowing the use of private land for Earth Disturbance Activity A construction or other human activity which disturbs the surface of thel land, including, but not limited to, clearing and grubbing, grading, excavations, embankments, road maintenance, building construction and the moving, depositing, stockpiling, or storing of soil, rock or earth materials. Emergency Spillway - A conveyance area thati is used top pass peak discharge greater than the maximum Encroachment - A structure or activity that changes, expands, or diminishes the course, current or cross Ephemeral stream - A: stream with flowing water only during, and for a short duration after, precipitation events in at typical year. Ephemeral streambeds are located above the water table year-round. Groundwater is not as source of water for the stream. Runoff from rainfall is the primary source of water for Erosion The natural process by which the surface of the land is worn away by water, wind or chemical Erosion and Sediment Pollution Control Plan A plan for a project site which identifies BMPs to Exceptional Value Waters - Surface waters of high quality which satisfy Pennsylvania Code Title 25 Environmental Protection, Chapter 93, Water Quality Standards, S 93.4b(b) (relating to anti-degradation). Extended Detention Volume (EDV) Release of detained runoff in excess of Permanently Removed Volume (PRV) over a period oft time not less than 24 and not more than 72 hours. Existing Condition - The dominant land cover during the five (5) year period immediately preceding a developed located such that overland or pipe flow from the site would flow towards it. Stormwater management purposes. design storm controlled by a Stormwater Management facility. section of a watercourse, floodway, floodplain, or body of water. stream flow. action. minimize accelerated erosion and sedimentation. proposed Regulated Activity. Felling The process of cutting down standing trees. rivers, and other waters of this Commonwealth. Flood A temporary condition of partial or complete inundation ofl land areas from the overflow of streams, Floodplain Any land area susceptible to inundation by water from any natural source or delineated by applicable Federal Emergency Management. Agency (FEMA) maps and studies as being a special flood hazard area. Also included are areas that comprise Group 13 Soils, as listed in Appendix A oft the Pennsylvania Department of Environmental Protection (PAI DEP) Technical Manuali for Sewage Enforcement Officers (as amended or replaced from time to time by PAI DEP). Floodway The channel of the watercourse and those portions of the adjoining floodplain that is reasonably required to carry and discharge the 100-year flood. Unless otherwise specified, the boundary of thet floodway is as indicated on maps and flood insurance studies provided by FEMA. In an area where no FEMA maps or studies have defined the boundary of the 100-year floodway, thei floodway includes floodplain areas within 501 feet oft the top of each stream bank and the stream channel itself. 6 Forest Management /Timber Operations - Planning and activities necessary for the management of forestland. These include timber inventory and preparation off forest management plans, silvicultural treatment, cutting budgets, logging road design and construction, timber harvesting, site preparation and Freeboard A vertical distance between the elevation oft the design high water elevation and the top ofa a dam, levee, tank, basin, swale, or diversion berm. The space is required as a safety margin in aj pond or Grade A slope, usually of a road, channel or natural ground specified in percent and shown on plans as specified herein. (To) Grade tot finish the surface of a roadbed, top ofe embankment or bottom of Grassed Waterway A natural or constructed waterway, usually broad and shallow, covered with erosion- Groundwater- Water beneath the earth's surface, often! between saturated soil and rock that supplies Groundwater Recharge Replenishment of existing natural underground water supplies without degrading reforestation. basin. excavation. resistant grasses, used to convey surface water. wells and springs. groundwater quality. Harvesting The felling, skidding, loading, and transporting oft timber products. High Quality' Waters Surface waters having quality which exceeds levels necessary to support propagation of fish, shelfish, and wildlife andi recreation in and on the water by satisfying Pennsylvania Code Title 25 Environmental Protection, Chapter 93 Water Quality Standards, S 93.4b(a). Hydric Soils - Soils that are characterized by the presence of water. Hydrograph - Ag graph of stormwater or runoff discharge versus time for a selected point in the drainage Hydrologic Soil Group (HSG) Infiltration rates of soils vary widely and are affected by subsurface permeability. as well as surface intake rates. Soils are classified into four HSG's (A,B,C, and D) according tot their minimum infiltration rate, whichi is obtained for bare soil after prolonged wetting. Thel Natural Resources Conservation Service (NRCS) of the US Department of Agricuiture defines the four groups and provides al list ofr most of the soils in the United States and their group classification. The soils underlying the project site may be identified from as soil survey report that can be obtained from local NRCS offices or conservation district offices. Soils become less! pervious as the HSG varies from A toD. Hydrophytic Vegetation - Plant life that is adapted to livingi in wet conditions. Impervious surfaces (or covers) shalli include, but not be limited to: system. Impervious Surface (Impervious Area) A surface that prevents the infiltration of water into the ground. i. roofs, additional indoor living spaces, patios, garages, storage sheds and similar structures ii. new streets or sidewalks, decks, parking areas, and driveway areas using traditional paved surfaces that prevent infiltration intot the ground. New decks, parking areas, and driveways are not defined as impervious areas if they are designed to allow long-term infiltration. 7 ii. existing gravel parking areas, driveways, andr roads shall be treated as slightly pervious and shall be analyzed using the appropriate SCS curve number based on their HSG; proposed gravel parking areas, driveways, and roads shall be treated as impervious areas for all calculations Impoundment- -Ar retention or detention basin designed to retain Stormwater runoff and release ita ata ac controlled Infiltration - Movement of surface water into the soil, where iti is absorbed by plant roots, evaporates into Infiltration Structures A: structure designed to direct runoff into the groundwater (e.g., French drains, rate. the atmosphere, or percolates downward to recharge groundwater. seepage pits, and seepage trench). Inlet- The upstream end of any structure through which water may flow. Runoff from rainfall is a supplemental source of water for stream flow. Intermittent Stream A stream with flowing water during certain times of the year, when groundwater provides water for stream flow. During dry periods, intermittent streams may not have flowing water. Karst - A type of topography or landscape characterized by surface depressions, sinkholes, rock pinnacles /uneven bedrock surface, underground drainage and caves. Karsti is formed on carbonate rocks, such as Landing (or deck) A place where logs or tree-length materials are assembled for loading and transport. Land Development (Development) - Inclusive of any or all of thei following meanings: () the improvement of one lot or two or more contiguous lots, tracts, or parcels ofl land for any purpose involving (a) agroup of two or more buildings, or (b) the division or allocation ofl land or space between or among two or more existing or prospective occupants by means of, or for the purpose of streets, common areas, leaseholds, condominiums, building groups, or other features; (i) any subdivision of land; (ii) development in Litter Layer Thel layer of fallen leaves, twigs, and decaying woody material that provides as sponge-like Lot- - A part of a subdivision or a parcel of land used as al building site ori intended to be usedi for building Main Stem (Main Channel) Any stream segment or other runoff conveyance facility used as a reach in Manning Equation (Manning formula) A method for calculation of velocity of flow (e.g., feet per second) and flow rate (e.g., cubic feet per second) in open channels based upon channel shape, roughness, depth off flow and slope. "Open channels" may include closed conduits SO long as the flow is not under pressure. Municipal Engineer - A professional engineer licensed as such in the Commonwealth of Pennsylvania, duly appointed as the engineer for al Municipality, planning agency orj joint planning commission. Natural Recharge. Area - Undisturbed surface area or depression where Stormwater collects, and a limestone or dolomite. accordance with Section 503(1.1) of the PAI Municipalities Planning Code. mat covering forest soils. purposes, whether immediate or future, which would not bet further subdivided. thel hydrologic model. Municipality - Borough of Ridgway, Elk County, Pennsylvania. portion of which infiltrates and replenishes the underground and groundwater. 8 Non-point Source Pollution Pollution that enters a water body from diffuse origins in the watershed and Non-structural Best Management Practice (BMPs) - Methods of controlling Stormwater runoff quantity and quality, such as innovative site planning, impervious area and grading reduction, protection of natural NPDES - National Pollutant Discharge Elimination System, the federal government's system for issuance of does not result from discernible, confined, or discrete conveyances. depression areas, temporary ponding on site and other techniques. permits under the Clean Water Act, which is delegated to PA DEP in Pennsylvania. NRCS-N Natural Resources Conservation Service (previously SCS). system discharges to surface waters of the Commonwealth. PAI DOT- Pennsylvania Department of Transportation. from the date of Municipal adoption of this ordinance. Outfall "Point source" as described in 40 CFR S 122.2 at the point where the Municipality's storm sewer Outlet- Points of water disposal to a stream, river, lake, tidewater or artificial drain. Parent Tract- - The parcel of land from which al land development or subdivision originates, determined Parking Lot Storage The use of parking areas as temporary impoundments with controlled release rates during rainstorms. Peak Discharge - The maximum rate of Stormwater runoff from a specific storm event. Permanently Removed Volume (PRV) - The volume ofr runoff thati is permanently removed from the runoff and not released intos surface Waters of this Commonwealth during or after a storm event. Pervious Surface (Pervious Area) - Any area or ground surface not defined- as impervious and that may Pipe Ad culvert, closed conduit, or similar structure (including appurtenances) that conveys Stormwater. Planning Commission The municipal or County planning commission authorized under the Pennsylvania Point Source any discernible, confined and discrete conveyance, including, but not limited to, any pipe, ditch, channel, tunnel, or conduit from which Stormwater is or may be discharged, as defined in State Post-Construction: - Period after construction where disturbed areas are stabilized, Stormwater controls are in place and functioning and all proposed improvements in the approved land development plan are be vegetated or un-vegetated. Municipalities Planning Code. regulations at 25F Pa. Code S 92.1. completed. Ple-development-UndeveopedNatura Condition. materials and other pollutants before they enter the system. Pre-treatment - Techniques employed in Stormwater BMPS to provide storage or filtering to trap coarse Project Site The specific area ofl land where any Regulated Activities in the Municipality are planned, Qualified Professional- - Al Professional Engineer licensed by the Pennsylvania Department of State Recharge - The replenishment of groundwater through the infiltration of rainfall or Stormwater runoff. conducted, orr maintained. qualified by law to perform the engineering work required by the Ordinance. 9 Record Drawings Those drawings maintained by the Applicant, Applicant's Contractor, or Applicant's Agent as the Applicants project is constructed; and upon which is documented the actual locations of the building components and changes to the original contract documents. These, or acopy of same, are Redevelopment - The demolition, construction, reconstruction, alteration, ori improvement exceeding 2,000 square feet ofl land disturbance performed on sites where existing land use is commercial, industrial, institutional, or multifamily residential. Maintenance activities such as top-layer grinding and re-paving are not considered redevelopment. Interior remodeling projects and tenant improvements are also not considered redevelopment. Utility trenches in streets are not considered redevelopment unless more than Regulated Activities All activities involving land development or earth disturbance activity that may affect Regulated Earth Disturbance Activity Activity involving Earth Disturbance subject to regulation under Release Rate - The percentage ofe existing conditions peak rate ofr runoff from a site or subarea to which the post-development peak rate ofr runoff must! be reduced to protect downstream areas. Retention Basin A: structure in which Stormwater is stored and not released during the storm event. Retention Basins dor not function without operational intervention to release stored Stormwater unless Retention/Removed - The volume ofr runoff thati is captured and not released directly into the surface Return Period The interval, in years, within which a storm event of a given magnitude can be expected, on average, to recur. For example, the 25-year return period rainfall would be expected, on average, to recur every twenty-five years. The probability of a 25-year storm occurring in any one yeari is 0.04 or 4% Riser- A vertical pipe extending from the bottom of a pond thati is used to control the discharge rate from Road Maintenance Earth disturbance activities within the existing road cross-section, such as grading and repairing existing unpaved road surfaces, cutting road banks, cieaning or ciearing drainage ditches and Roof Drains A drainage conduit or pipe that collects water runoff from a roof and leads it away from the Rooftop Detention Temporary ponding and gradual release of Stormwater falling directly onto flat roof turned over tot the Municipality at the completion oft the project. 50% of the street width is removed andi re-paved. stormwater runoff. 25 PA Code Chapters 92, Chapter 102, or the Clean Streams Law. designed asi infiltration-only basins. Waters oft this Commonwealth during or after a storm event. the pond for a specified design storm. other similar activities. structure. surfaces byi incorporating controlled-flow roof drains into building designs. Runoff- Any part ofp precipitation that flows over the land. SALDO-S Subdivision and Land Development Ordinance. SCS-S Soil Conservation Service (currently known as NRCS, Natural Resources Conservation Service). Also a commonly referred to method ("SCS Method") for the hydrologic computation and estimation of runoff from rainfall information that has been developed by the United States Department of Agriculture's Sediment Soils or other materials transported by surface water as a product ofe erosion. Soil Conservation Service (SCS). 10 Sediment Basin A barrier, dam, retention or detention basin located and designed to retain rock, sand, Sediment Pollution Thej placement, discharge or any otheri introduction of sediment into the waters oft the Sedimentation The process by which mineral or organic matter is accumulated or deposited by the Seepage Pit/Seepage Trench An area of excavated earth filled with loose stone or similar coarse material, into which surface water is directed for infiltration into the groundwater. Separate Storm Sewer System A conveyance or system of conveyances (including roads with drainage systems, Municipal streets, catch basins, curbs, gutters, ditches, man-made channels or storm drains) Shallow Concentrated Flow- Stormwater runoff flowing in shallow, defined rills prior to entering a defined Sheet Flow- - A flow process associated with broad, shallow water movement on sloping ground surfaces Skidding Moving of logs or felled trees along the surface oft the ground from the stump to the point of Skid Road/Haul Road - Those roads, trails, or other openings upon which trees, logs, equipment, or Slash - Unusable woody material such as large limbs, tops, culll logs, and stumps that remain after timber Soil-Cover Complex Method A A method ofr runoff computation developed by the NRCS thati is based on relating soil type and land uselcover to a runoff parameter called Curve Number (CN). Special Geologic Features Carbonate bedrock features, including but not limited to closed depressions, existing sinkholes, fracture traces, lineaments, joints, faults, caves and pinnacles, which may exist and must bei identified on a site when Stormwater management BMPS are being considered. Spillway - A conveyance that is used to pass the peak discharge oft the maximum design storm controlled State Water Quality Requirements The regulatory requirements to protect, maintain, reclaim, and restore water quality under Pennsylvania Code Title 25 and the Clean Streams Law. Storage Indication Method A reservoir routing procedure based on solution of the continuity equation (inflow minus outflow equals the change in storage) with outflow defined as ai function of storage volume Storm Frequency The number of times that a given storm "event" occurs or is exceeded on the average Storm Sewer A system of pipes andlor open channels that convey intercepted runoff and Stormwater Stormwater Drainage runoff from the surface of the land resulting from precipitation or snow ori ice melt. gravel, silt, or other material transported by water during construction. Commonwealth. movement of water or air. primarily used for collecting and conveying Stormwater runoff. channel or waterway. thati is not channelized or concentrated. loading. vehicles are moved within the site of the work. harvesting. by the Stormwater facility. and depth. ina a stated period ofy years. See "Return Period". from other sources, but exclude domestic sewage and industrial wastes. 11 Stormwater Management Facility- Any structure, natural or man-made, that, due to its condition, design, or construction, conveys, stores, or otherwise affects Stormwater runoff. Typical Stormwater management facilities include, but are not limited to, detention and retention basins, open channels, storm sewers, pipes, Stormwater Management Plan - Thep plan for managing Stormwater runoff adopted by the County of Elk asi required by the Act of October 4, 1978, P.L. 864, (Act 167), as amended, andl known as the' Stormwater Stormwater Management BMPs Is abbreviated as SWMI BMPs throughout this Ordinance. Stormwater Management Site Plan The plan prepared by the Applicant or his representative indicating how Stormwater runoff willl be managed at the project site in accordance with this Ordinance. Stormwater Management Site Plan will be designated as SWM Site Plani throughout this Ordinance. andi infiltration structures. Management Act". Stream - A natural watercourse. Stream Enclosure - A bridge, culvert or other structure in excess of 1001 feet inl length upstream to Subarea (Sub-watershed) The smallest drainage unit of a watershed for which Stormwater management Subdivision The division or re-division of a lot, tract or parcel of land by any means into two or more lots, tracts, parcels or other divisions of land including changes in existing lot lines for the purpose, whether immediate or future, ofl lease, partition by the court for distribution to heirs or devisees, transfer of ownership or building or lot development (Refer to thel PAI Municipalities Planning Code, current version.) Surface Waters of the/this Commonwealth Any and all rivers, streams, creeks, rivulets, ditches, watercourses, storm sewers, lakes, dammed water, wetlands, ponds, springs, and all other bodies or channels of conveyance of surface, or parts thereof, whether natural or artificial, within or on the downstream that encloses a regulated water oft this Commonwealth. criteria havel been established in the Stormwater Management Plan. boundaries of this Commonwealth. Swale - Al low-lying stretch of land that gathers or carries surface water runoff. Timber Operations - See Forest Management. time and flow time in pipes or channels, ifa any. Time-or-Concentration (Tc)- The time for surface runoff tot travei from the hydraulically most distant point oft the watershed to aj point ofi interest within the watershed. This time is the combined total of overland flow Top-of-Bank- - Highest point of elevation in as stream channel cross section at which a rising water level just begins toi flow out of the channel and over the floodplain. USACE- United States Army Corp of Engineers Vernal Pond - Seasonal depressional wetlands that are covered by shallow water for variable periods from Watercourse- A channel or conveyance of surface water having defined bed and banks, whether natural Waters of the/this Commonwealth - Rivers, streams, creeks, rivulets, impoundments, ditches, watercourses, storm sewers, lakes, dammed water, wetlands, ponds, springs and other bodies or channels ofconveyance of surface and underground water, or parts thereof, whether natural or artificial, within or on winter to spring, but may be completely dry for most oft the summer andi fall. or artificial, with perennial ori intermittent flow. thel boundaries of this Commonwealth. 12 Watershed Region or area drained by a river, watercourse or other body of water, whether natural or Wet Basin - A detention basin that is designed to detain Stormwater and which always contains water. Wetland Those areas that arei inundated or saturated by surface or ground water at a frequency and duration sufficient to support, and that under normal circumstances do support, a prevalence of vegetation typically adapted for life in saturated soil conditions, including swamps, marshes, bogs, fens, and similar artificial. areas. 13 ARTICLE II-STORMWATER MANAGEMENT STANDARDS Section 301. General Requirements A. Written approval of a SWM Site Plan must be obtained from the Municipality prior to commencement of Regulated Activities unless the proposed activity is specifically exempt from B. SWM Site Plans approved by the Municipality shall be on site throughout the duration of the C. The Municipality may; after consultation with the PA DEP, approve measures for meeting the State Water Quality Requirements other than those in this Ordinance, provided they meet the minimum requirements of, and do not conflict with, State lawi including but not limited to the D. For all Regulated Activities, implementation of peak rate controls and preparation of a SWM Site Plan are required, unless exempted by Section 302 of this Ordinance. this requirement under Section 302. Regulated Activity. Clean Streams Law. E. Impervious Areas: 1. Ther measurement ofi impervious areas shall include all oft thei impervious areas in the total proposed development eveni if development is to take place in stages. 2. For development taking place in stages, the entire development plan must be used in 3. For projects that add impervious area to a parcel, the total impervious area on the parcel is subject to the requirements oft this ordinance, unless, the project is otherwise deemed exempt from stormwater management provisions per the criteria set forth in 4. Existing gravel parking areas, driveways, andi roads shall not be considered impervious. These areas shall be treated as semi-pervious and shall be analyzed using the appropriate SCS curve number based on the appropriate HSG underlying determining conformance with this Ordinance. Section 302. the gravei areas, which is defined as: a. HSG A- Gravel Area Curve Number shall be 76 b. HSGI B -Gravel Area Curve Number shall be 85 C. HSG C- Gravel Area Curve Number shall be 89 d. HSGI D- Gravel Area Curve Number shall be 91 5. Proposed gravel parking areas, driveways, and roads shall be considered impervious. F. Concentrated stormwater discharges onto adjacent property shall not be created, increased, decreased, or relocated, or otherwise altered without written notification of] permission from] adjacent property owner(s). Such discharges shall be subject to the requirements oft this Ordinance. G.A All regulated activities shall include such measures as necessary to: 1. Protect health, safety, and property; 14 2. Meet the water quality goals of this ordinance byi implementing measures to: a. Minimize disturbance tot floodplains, wetlands, natural slopes over 15%, and b. Minimize thermal impacts to' Waters of the Commonwealth. C. Preserve and maintain trees and woodlands. Maintain or extend riparian buffers and protect existing forested buffer. Provide trees and woodlands d. Establish and maintain non-erosive flow conditions ini natural flow pathways. e. Minimize soil disturbance and soil compaction. Cover disturbed areas with topsoil having a minimum depth of 4 inches. Use tracked equipment for f. Disconnect impervious surfaces by directing runoff to pervious areas. existing native vegetation. adjacent toi impervious areas. grading. 3. Implement Volume Controls in Section 304. Development Practices) whenever practical. 4. Incorporate the techniques described in Appendix A of this Ordinance (Low Impact 5. The Applicant must demonstrate that thet following BMPS are being used to the maximum extent practicable tor receive consideration for the exemptions in Section a. Design around and limit disturbance of Floodplains, Wetlands, Natural Slopes over 15%, existing native vegetation, and other sensitive and special value 302: features. b. Maintain riparian and forested buffers. C. Limit grading and maintain non-erosive flow conditions in natural flow paths. d. Maintain existing tree canopies near impervious areas. e. Minimize soil disturbance and reclaim disturbed areas with topsoil and vegetation. Direct runoff to pervious areas. area will not adversely impact thei following: b. Velocities and erosion. C. Quality ofr runoffi if direct discharge is proposed. d. Existing known problem areas. e. Safe conveyance of the additional runoff. Downstream property owners. 6. The Applicant must demonstrate that the proposed evelopmentadatuonal impervious a. Capacities ofe existing drainage ways and storm sewer systems. 15 H. The design of all facilities over Karst shall include an evaluation ofr measures to minimize Infiltration BMPS shall be spread out, made as shallow as practicable, andl located to maximize use ofr natural on-site infiltration features while still meeting the other requirements of this J. Storage facilities shall completely drain both the volume control and rate control capacities over a period oft time not less than 24 and noti more than 721 hours from the end of the design K. The design storm volumes to be used in the analysis of peak discharge rates shall be obtained from the Plecptaton-requency Atlas of the United States, Atlas 14, Volume 2, US Department of Commerce, National Oceanic and Atmospheric Administration, National Weather Service, Fydrometeorologica Design Studies Center, Silver Spring, Maryland, 20910. adverse effects. Ordinance. storm. NOAA's Atlas 14 can be accessed at Internet address: ttp./ndsc.nws.noaa.gov/hdscptas. The Municipality and its Engineer may require that regulated activities maintain a minimum distance between proposed impervious areas/stormwater management facility outlets and M. SWM BMPS for all Regulated. Activities shall be designed, implemented, operated, and maintained to meet the purposes andi requirements of this Ordinance and to meet all requirements under Title 25 of the Pennsylvania Code, the Clean Streams Law, and the N. For all regulated earth disturbance activities, erosion and sediment control BMPS shall be designed, implemented, operated, andi maintained during the regulated earth disturbance activities (e.g., during construction) tor meet the purposes and requirements of this Ordinance and to meet all requirements under Title 25 of the Pennsylvania Code and the Clean Streams Law. Various BMPS and their design standards are listed in the Erosion and Sediment Pollution Control Program Manual (E&S Manual), No. 363-2134-008 (April 15, 2000), as amended and updated. down slope property line(s). Stormwater Management. Act. Section 302. Exemptions A. Under no circumstance shall the Applicant be exempt from implementing such measures as necessary to: 1. Meet special requirements for projects within High Quality (HQ) and Exceptional Value B. The Applicant must demonstrate that the following BMPS are being used to the maximum (EV) watersheds (Section 307.G). extent practicable to receive consideration for the exemptions: 1. Design around and limit disturbance of Floodplains, Wetlands, Natural Slopes over 15%, existing native vegetation, and other sensitive and special value features. 3. Limit grading and maintain non-erosive flow conditions in natural flow paths. 2. Maintain riparian and forested buffers. 16 4. Maintain existing tree canopies near impervious areas. 5. Minimize soil disturbance and reclaim disturbed areas with topsoil and vegetation. . The Applicant must demonstrate that the proposed evelopmentadationa impervious area 6. Direct runoff to pervious areas. will not adversely impact the following: 1. Capacities of existing drainage ways and storm sewer systems. 2. Velocities and erosion. 3. Quality ofr runoffi if direct discharge is proposed. 4. Existing known problem areas. 5. Safe conveyance oft the additional runoff. 6. Downstream property owners. D. An Applicant proposing Regulated Activities, after demonstrating compliance with Sections 302.A, 302.B, and 302.C, may be exempted from various submission requirements of this Ordinance according to thei following table: Table 302-1 New Impervious Area OSF snewi impervious area <1000 SF Applicant Submission Requirements No Submission Required 1000 SF S new impervious area <2 2500 SF Small Project SWM Application1 (See Appendix KF) 2500 SF S new impervious area <5000 SF Volume Control (Section 304) and Small Project SWM Application (See Appendix F) Peak Rate Control (Section 305), Volume Control (Section 304), and Stormwater Management Site Plan (Article IV) 5000 SF S new impervious area AIl Regulated. Activities must comply with the State Water Quality Requirements. E. New Single Family Residential activities on as single lot are exempt from the requirements of Section 304- Volume Control, Section 305- Peak Rate Control, andi from the submission ofa Small Project SWM Application provided the construction: 1. Complies with Sections 302.A, 302.B, ,302.C, and 1Ther municipality can require the applicant toy provide supplemental and additional information beyond the Small Project SWM Application ift therei is at threat top property, health or safety 17 2. Has building setbacks of atl least 751 feet from downslope property lines, and 3. Driveways: a. Runoff must discharge onto pervious surface with agravel strip or other b. No more than 1,000 square feet of paved surface may discharge to any one C. Foreach discharge point; the length of flow- on the pervious surface must exceed the spreading device. point. length of flow ont the paved surface. F. The Municipality may, after consultation with the PAI DEP, approve alternative stormwater management controls for meeting the State Water Quality Requirements other than those in this Ordinance, provided they meet the minimum requirements of, do not conflict with State law 1. The alternative controls are documented to be acceptable to PADEP (or Delegated Authority), for NPDES requirements pertaining to post construction stormwater 2. The alternative controls comply with all other sections oft this ordinance, including but G. Agricultural activities are exempt from the rate and SWM Site Plan preparation requirements of this ordinance provided the activities are performed according to the requirements of25 H. Forest management and timber operations are exempt from the rate and volume control and SWM Site Plan preparation requirements of this ordinance provided the activities are performed according to the requirements of 25 Pa.Code Chapter 102. Refer to Section 309 for additional information and guidance concerning timber operations. Exemptions from any provisions oft this Ordinance shall not relieve the Applicant from the requirements in Sections 301.D,F,G,H,,andi K. Proposed Municipal projects are bound to the following requirements and criteria: including but not limited to the Clean Streams Law, and provided that: management requirements. not limited to Sections 301.Cand 302.A-C. Pa.Code Chapter 102. Table 302-2 Description: Type of Project Requirements: Change the roadway by either reducing or eliminating BMPi implementation that uses horizontal and vertical curves, or changing ther roadway's non-structural and restoration Alignments' superelevation. practices such as: Street sweeping Impervious disconnection Pull-Offs' New, as part of al larger project or byi itself. 18 Table 302-2 Description: Type of Project Requirements: Increase the width oft the existing travel lanes (no new lanes added) and shoulders, or extension of acceleratonldeceleraton ramps in existing shoulder Widening" areas. Nominal channelization ofi intersections and addition of Minor practices and BMP Intersection' turning lanes. implementation that usesl low- impact practices such as: Preservation ofe existing vegetation Pavement Replace portions, overlay, or mill and resurface the roadway'ss surface. Resurface, stabilize, upgrade (dirt or gravel to paved), or Minimization ofs soil compaction Shoulders widen the existing shoulders within the existing footprint. Maintenance of Erosion Control and any PCSME BMPS Restoration and stabilization of staging areas Replace and/or repair guide rail, signs, trafic signals, and drainage systems to their original specifications; various minor safety improvements. Other Addition of one or more travel lanes, including Peak Rate Control (Section 305), and Stormwater Management Site Plan Major Widening' New Alignment" Municipal Facilities acceleration and deceleration lanes, to an existing road. Volume Control (Section 304), New roadway corridor. interchange area, etc. this section Interchange' Reconfiguration ofr ramps, lane modification within New stockpile sites, buildings, or other structures or facilities not otherwise addressed by the requirements of Projects falling into the noted categories and that have the potential to discharge into surface waters that have existing or designated HQ or EV uses (including EV wetlands), have impairments due to stormwater, are connected to combined sewer systems, or have the potential to have an adverse effect ont threatened or endangered species, or critical habitat for such species, are subject to additional stormwater management requirements, beyond the requirements listed in the table. The additional BMP measures that must be considered andi implemented for projects occurring in these areas are as follows: 19 Table 302-3 Constructed wetlands/Wet Significant detention ofp peakf flow rates is needed and the contributing ponds Permeable pavement Manufactured products: quality inlets, etc. drainage area is large; retrofit existing detention basins are feasible. Subsurface storage products are designed to attenuate peak runoff events structures or inserts are designed to minimize the discharge of solids, floatables, and oillgrease pollutants. Regular maintenance oft these Parking lots only. Subsurface storage, water through infiltration and/or discharge rate reduction. Storm sewer inlet products is necessary. Projects occurring in the areas listed above and not previously bound to such requirements (roadway restoration projects), are also required to achieve the following targeted outcomes: 1. For project areas within ar release rate district, reduce the post-construction runoff peak rate as required byt the release rate districti int this Ordinance. For project areas not within a release rate district, reduce the post-construction runoff peak rate to the pre- construction peak rate for the 1-year through 100-year storm events. 2. Reduce the post-construction runoff volume to the pre-construction runoff volume for the 2-year 24-hour storm event and smaller. Section 303. Waivers A. The provisions of this Ordinance are the minimum standards for the protection of the public B. Waivers shall not be issued from implementing such measures as necessary to: 1. Meet State Water Quality Standards and Requirements. 2. Protect health, safety, and property. 3. Meet special requirements for High Quality (HQ) and Exceptional Value (EV) C. Thel Municipality will consider waiver requests in accordance with Section 301.C. Ifan Applicant demonstrates to the satisfaction oft the governing body of the Municipality that any mandatory provision of this Ordinance is unreasonable or causes unique or undue unreasonableness or hardship as it applies to the proposed Project, or that an alternate design may resulti in a superior result within the context of Section 102 and 103 oft this Ordinance, the governing body of the Municipality upon obtaining the comments and recommendations of the Municipal Engineer and Conservation District may grant a waiver or relief sot that substantial justice may be done and the public interest is secured; provided that such waiver will not have D. The Applicant shall submit all requests for waivers in writing and shall include such requests as ap part of the plan review and approval process. The Applicant shall state in full the facts of unreasonableness or hardship on which the request is based, the provision or provisions oft the Ordinance that are involved, and the minimum waiver or relief that is necessary. The Applicant shall state how the requested waiver and how the Applicant's proposal shall result in an equal watersheds. the effect of nulifying thei intent and purpose of this Ordinance. 20 or better means of complying with the requirements oft this Ordinance including but not limited E. The Municipality shall keep a written record of all actions on waiver requests. The Municipality may charge a fee for each waiver request, which shall be used to offset the administrative costs of reviewing the waiver request. The Applicant shall also agree to reimburse the Municipality for reasonable and necessary fees that may be incurred by the Municipal Engineer F. Ing granting waivers, the Municipality may impose reasonable conditions that will, ini its judgment, secure substantially the objectives of the standards or requirements that are tol be G. The Municipality may grant applications for waivers when thet following findings are made, as to Section 301, General Requirements. ina any review of a waiver request. modified. relevant: 1. That the waiver shall resulti in an equal or better means of complying with the intent of this Ordinance. 2. That the waiver is the minimum necessary to provide relief. 3. That the applicant is not requesting a waiver based on cost considerations. 4. That existing down gradient stormwater problems will not be exacerbated. 5. That runoff is not being diverted to a different drainage area. 7. That potential icing conditions will not occur. 6. That increased flooding or ponding on off-site properties or roadways will not occur. 8. Thati increases in peak flow or volume from the site will not occur. 9. That erosive conditions due to increased peak flows or volume will not occur. 10. That adverse impact to water quality will not result. 11. That increased 100-Year Floodplain levels will not result. 12. That increased or unusual municipal maintenance expenses will not result from the 13. That the amount of stormwater generated has been minimized tot the greatest extent 14. That infiltration ofr runoff throughout the proposed site has been provided where practicable and pre-development ground water recharge protected. 15. That peak flow attenuation ofr funoff! has been provided. 16. That long-term operation and maintenance activities are established. waiver. allowed. 17. That the receiving streams and/or water bodies will not be adversely impacted in flood carrying capacity, aquatic habitat, channel stability and erosion and sedimentation. 21 Section 304. Volume Controls Thel low impact development practices provided in the PA BMP Manual shall be used for all regulated activities tot thei maximum extent practicable. Water volume controls shall bei implemented using the Design Storm Method in Subsection A or the Simplified Method in Subsection B below. For regulated activity areas equal or less than 1 acre that do not require hydrologic routing to design the stormwater facilities, this Ordinance establishes no preference for either methodology; therefore, the applicant may select either methodology on thel basis ofe economic considerations, the intrinsic limitations on applicability oft the analytical procedures associated with each methodology, and other factors. A. The Design Storm Method (CG-1 in the PA BMP Manual (current version)) is applicable to any size of Regulated Activity. This method requires detailed modeling based on site conditions. 1. Do noti increase the post development total runoff volume for all storms equal to or less than the 2-year 24-hour duration precipitation. 2. For modeling purposes: a. Existing pre-development) non-forested pervious areas must be considered b. Twenty (20) percent of existing impervious area, when present, shall be considered meadowi in the model for existing conditions. meadow ori its equivalent. B. The Simplified Method (CG-2i in the PAI BMPI Manual (current version)) provided below is independent of site conditions and shall be usedi if the Design Storm Method is not followed. This method is not applicable to Regulated Activities that disturb greater than one (1) acre, or for projects that require design of stormwater storage facilities. For new impervious surfaces: 1. Stormwater facilities shall be sized to capture at least the first two inches (2")ofrunoff 2. Atleastt thet first one inch (1.0") ofr runoff from newi impervious surfaces shall be permanently removed from the runoff flow- i.e. its shall not be released into the surface Waters oft this Commonwealth. Removai options inciude reuse, evaporation, 3. Wherever possible, infiltration facilities shall be designed to accommodate infiltration of the entire permanently removed runoff; however, in all cases at least the first one-half inch (0.5") oft the permanently removed runoff shall bei infiltrated. 4. This method is exempt from the requirements of Section 305, Rate Controls. from all newi impervious surfaces. transpiration, andi infiltration. Section 305. Rate Controls A. Areas not covered by a Release Rate Map from an approved Act 167 Stormwater Management Plan: 22 Post-development discharge rates shall not exceed the Pre-Development discharge rates for the 1,2,10.,25,50. and 100-year storms. Ifiti is shown, that the peak rates of discharge indicated by the post-development analysis are less than or equal tot the peak rates of discharge indicated by the pre-development analysis for 1-, 2-, 10-, 25-, 50-, and 100-year, 24- hour storms, then the requirements oft this section havel been met. Otherwise, the applicant shall provide additional controls as necessary to satisfy the peak rate of discharge B. Areas covered by al Release Rate Map from an approved Act 167 Stormwater Management For the 1-, 2-, 10-, 25-, 50-, and 100-year storms, the post-development discharge rates will follow the release rate maps in this Ordinance. For any areas not shown on the release rate maps, the post-development discharge rates shall not exceed thel Pre-Development discharge requirement. Plan: rates. C. BMPs for Rate Controls: AI list of BMPS for peak rate controls is provided in Appendix B, Item C. Section 306. Calculation Methods A. Stormwater runoff from all project sites shall be calculated using a generally accepted calculation technique thati is based on the NRCS soil cover complex method. Table 306-1 summarizes acceptable computation methods and the method selected by the Qualified Professional shall be based on the individual limitations and suitability ofe each method for a TABLE3061-ACCEPTABLE COMPUTATION METHODOLOGIES FOR particular site. STORMWATER MANAGEMENT PLANS Method Developed By USDA NRCS USDA NRCS Method TR-20/WINTR20 (or commercial computer package based on TR-20) TR-55/WINTR55 (or commercial computer package based on TR-55) HEC-HMS Applicability Applicable where use off fulll hydrology computer modei is desirabie or necessary. Applicable forl land development plans within limitations described in TR-55. Applicable where use off full hydrologic computer model is desirable or necessary. time of concentration less than 60 minutes (T< 60 min), or as approved by the Municipality Other computation methodologies US Army Corps of Engineers Rational Formula (or commercial computer package based on Rational Formula) Other Methods such as Emil Kuichling (1889) For sites less than fiftly acres and with Varies 23 TABLE306-1-A ACCEPTABLE COMPUTATION METHODOLOGIES FOR STORMWATER MANAGEMENT PLANS Method Developed By Method SWMM, WMS, etc. Applicability approved by the Municipality Note: Successors to the above methods are also acceptable. B. All calculations consistent with this Ordinance using the soil cover complex method shall use the appropriate design rainfall depths andi intensities for the various return period storms according to the approximate center of the proposed development site, in accordance with the values obtained from the National Oceanic and Atmospheric Administration's (NOAA) Hydrometeorological Design Studies Center Precipitation Frequency Data Server (PFDS) at the following location for the Commonwealth of Pennsylvania: tp/ndsenwsnoagownocpids/ndezhm Applicant shall provide documentation of PFDS data location (latitude and longitude in C. All calculations using the Rational Formula shall use rainfall intensities consistent with appropriate times-oFconcentration for overland flow and return periods from the NOAA, PFDS website, thel Design Storm Curves from PennDOT Publication 13M, Design Manual Part 2, D. Times--concentation for overland flow shall be calculated using the methodology presented in Chapter 3 of Urban Hydrology for Small Watersheds, NRCS, TR-55 (as amended or replaced from time to time by NRCS). Times-okconcentration for channel and pipe flow shall be computed using Manning's equation. NRCS lag equation divided by 0.6 as acceptable E. Inorder to reduce stormwater runoff volumes from developed areas and encourage groundwater recharge, underground basin drains, infiltration trenches, dry wells, and cisterns are permitted to which roof leaders may be connected. These drains consist of stone-filled basins that temporarily store and release water below ground surface. Plans for such facilities shall be submitted to the Municipality for approval, and thel basins shall be used onlyi in those F. Runoff Curve Numbers (CN) for both existing and proposed conditions to be used in the soil cover complex method shall be obtained from Table 2-2 oft the TR-55 manual. G. Runoff coefficients (C) for both existing and proposed conditions for use in the Rational H. All flow assumptions and source of supporting data shall be provided as part of the overall plan. The Municipality reserves the right to reject any submitted values, despite the source, Where uniform flow is anticipated, the Manning equation shall be used for hydraulic computations, and to determine the capacity of open channels, pipes, and storm sewers. Values for Manning's roughness coefficient (n) shall be consistent with generally accepted values from al legitimate and verifiable source. All flow assumptions ands source of supporting egesminutesseconas, Chapter 10, andl NOAA Atlas 14. method for Tci inundeveloped areas. areas where soils, geologic, and water table conditions permit. Formula are provided in Appendix D. and top provide as substitute source for use by the applicant. 24 data shall be provided as part of the overall plan. The Municipality reserves the right to reject any submitted values, despite the source, and to provide a substitute source for use by the applicant. Full flow capacity shall be assumed for closed conduits. Storm sewer systems consisting ofr more than three pipe junctions shall be designed using hydraulic grade line J. - Outlet structures for Stormwater management facilities shall be designed tor meet the performance standards of this Ordinance using any generally accepted hydraulic analysis The design of any Stormwater detention facilities intended to meet the performance standards of this Ordinance shall be verified by routing the design storm hydrograph through these facilities using the Storage-Indication Method. For drainage areas greater than 200 acres in size, the design storm hydrograph shall be computed using a calculation method that produces computations. technique or method. afull hydrograph (ie. TR-20, TR-55, ànd HEC-HMS). K. Stormwater management and related facilities shall be provided: 1. Top permit unimpeded flow of natural watercourses. Such flow may be redirected as required, subject to the approval oft the Pennsylvania Department of Environmental Protection and the Municipality. 2. Toensure adequate drainage of all street low points. L. Storm sewers and related installations: 1. Storm sewers, where required by zoning and land use densities, shall be placed under ori immediately adjacent to the roadway side oft the curb, or as directed by the Municipality, when parallel to the street within the right-of-way. 2. When located in undedicated land, they shall be placed within a drainage easement not less than twenty (20) feet wide as approved by the Municipality. 3. The use of properly designed, graded, and vegetated drainage channels is encouraged in lieu of storm sewers in commercial and industrial areas and, where approved by the Municipality, in residential areas. Such swales shall be designed to not only carry the required discharge without excessive erosion, but also to increase the time of concentration, reduce the peak discharge and velocity, and permit the water to percolate into the soil, where appropriate. Criteria related to- the use and a. Where vegetated drainage swales are usedi in lieu of ori in addition to storm sewers, they shall be designed to carry the 10-year discharge without erosion, and also to increase the time of concentration, reduce the peak discharge and velocity, and permit the watert to percolate into the soil. b. The maximum encroachment of water on the roadway pavement along roadside swales in cut areas shall not exceed half of a through traffic lane during a 10-year frequency storm of five (5) minute duration. Frequent andlor design of drainage swales are as follows: sustained flooding oft the sub-base shall be avoided. 25 The design of all vegetated channels shall, as a minimum, conform to the design procedures outlined in the Erosion and Sediment Pollution Control Program Manual (PAI DEP). Inlets shall be provided to limit road shoulder d. The side slope for any vegetated drainage channel requiring mowing of the vegetation shall have a maximum grade of three (3) horizontal to one (1) vertical on those areas to be mowed. Maximum side slopes for any vegetated drainage channel shall be two (2) horizontal to one (1) vertical. e. Erosion Prevention: All drainage swales shall be designed to prevent the erosion oft the bed and bank areas. Suitable temporary and/or permanent stabilization during vegetative cover establishment shall be provided to Storm sewers or drainage swales shall discharge to a detention or retention basin to attenuate the peak rate and volume, respectively ofs stormwater encroachment and water velocity. prevent erosion. runoff, except as provided int the plan. 4. The design capacity of storm sewers shall be in accordance with PennDOT Drainage Manual, Publication Number 584, as amended. Storm drainage systems shall be designed without surcharging inlets to provide conveyance of stormwater runoff into a detention basin or similar facility utilized to manage the rate of stormwater runoff. To avoid surcharging inlets, and to ensure thati inlets will receive stormwater runoff, the hydraulic grade line att the inlet shall be at least six (6) inches below the elevation of the inlet grate. Where site grading will direct stormwater runoff from the 100-year design storm to a detention basin or similar facility utilized to manage the rate of stormwater runoff, then the storm sewer may be designed for the 10-year design storm. Where site grading will not direct stormwater runoff from the 100-year design storm to a detention basin or similar facility utilized to manage the rate ofs stormwater runoff, then the storm sewer shall be designed for the 100-year design storm. The location of the hydraulic grade line for the 100-year design storm shall be graphically shown on the required storm sewer profle drawings. Conveyance of storms tot the detention basin, up to and including the 100-year frequency, shail be provided so as 5. Storm inlet types andi inlet assemblies shall conform to the Pennsylvania Department ofTransportation Standards for Roadway Construction as approved by the 6. Accessible drainage structures shall bel located on a continuous storm sewer system ata all vertical dislocations, at all locations where a transition in storm sewer pipe sizing is required, at all vertical and horizontal angle points exceeding five (5) degrees, and ata all points of convergence of two or more influent storm sewer mains. The construction locations of accessible drainage structures shall be as indicated on the subdivision drainage plan or area drainage plan approved by the Municipality. 7. When evidence available to thel Municipality indicates that existing storm sewers have sufficient capacity as determined by hydrograph summation and are accessible, proposed stormwater facilities may connect to the existing storm sewers sol long as the peak rate of discharge does not exceed the amount permitted by this Article. not to endanger life or seriously damage property. Municipality. 26 M. Downstream Analysis 1. Where deemed necessary by the Municipal Engineer, the applicant shall submit an analysis of thei impacts of detained stormwater flows on downstream areas within the watershed, established with the concurrence oft the Municipal Engineer. The analysis shall include hydrologic and hydraulic calculations necessary to determine thei impact ofp peak discharge modifications oft the proposed development on critical locations such as dams, tributaries, existing developments, undersized culverts, andf flood prone areas. Review and comment oft the analysis by the Engineer of a downstream Municipality shall be obtained as deemed necessary. N. Multiple Use Basins: The design and construction ofr multiple use stormwater detention facilities are strongly encouraged. In addition to: stormwater management; where appropriate, facilities allow for recreational uses including: ball fields, play areas, picnic grounds, etc. Provision for parking facilities within basins andp permanent wet ponds with stormwater management capabilities may also be appropriate. Priora approval and consultation with the Municipality are required before design. Multiple use basins shall be constructed so that 0. Multiple Development Basins: Stormwater management facilities designed to serve more than onep property or development in the same watershed are encouraged. Staged construction of existing or proposed multiple-use detention facilities by several developers in conjunction with watershed development is encouraged. Each applicant shall be responsible for the incremental increase in stormwater runoff generated by the respective development and incremental construction improvements necessary for the overall detention facility. Prior approval and consultation with the Municipality is required before design of such facilities. P.A Alternative Detention Facilities: Alternative stormwater detention facilities including roof top, subsurface basins or tanks and in-pipe detention storage, or other approved alternative Q. Landscaping of Stormwater management facilities: Facilities constructed with berms or earthen embankments shall not be landscaped along the top of the impoundment berm, embankment, nor shall other facility areas constructed from compacted fill materials be landscaped. Heavy vegetative cover root penetration can cause soil weakening and damage potentially dangerous conditions are not created. designs are permitted as determined by the Municipality. tof facility piping. Section 307. Other Requirements A. All wet basins shall be designed in a manner thats seeks to mitigate the proliferation of mosquito breeding habitats and the potential spread of the West Nile Virus. This can be 1. The design of a Stormwater wetland/wet basin must include the selection of hydrophytic plant species for their pollutant uptake capabilities and for not contributing to the potential for vector mosquito breeding. The establishment of hydrophytic vegetation will promote the population of the wetland/ wet basin by amphibians and other mosquito predators. Inr natural wetlands, predatory insects and amphibians are effective at keeping mosquito populations in check during the larval stage of accomplished through the following means: 27 development while birds and bats prey on adult mosquitoes. Refer to Appendix Bof the PA SWM BMP Manual (current version) for hydrophytic native plant species lists. 2. Aeration fountains and stocked fish can be added tol keep larval mosquito populations inc check. B. The Municipality reserves the right to disapprove any design that would resulti in the . When the elevation of any existing or proposed entrance to a structure, including windows, is lower than the elevation of the public cartway serving thats site, ag grading plan shall be submitted, reviewed and approved as part oft the SWM approval process fort the proposed D. No Stormwater detention facility shall be placed within fifty (50) feet of a special geologic feature. No subsurface Stormwater conveyance facility shall be constructed within fifty (50) feet of a special geologic feature, without written permission of the Municipality. E. Stormwater management facilities located outside of existing or proposed public rights-of-way shall be located within and accessible by easements granted to the Municipality as follows: 1. Drainage Easements: Where at tract is traversed by a watercourse, drainageway, channel or stream, there shall be provided a drainage easement paralleling the centerline of such watercourse, drainageway, channel or stream. The width oft the drainage easement willl be adequate to preserve the unimpeded natural flow oft the 100-year storm, in accordance with computed top widths for water surface elevations. Drainage easements shall provide for maintenance, and fori the purpose of widening, 2. Access Easements: Where proposed stormwater management facilities are not adjacent to proposed or existing public right-of-ways or are not accessible due to physical constraints, as determined by the Municipality, a twenty (20) feet wide access easement specifying rights of entry shall be provided. Access easements shall provide for vehicle ingress and egress on grades of less than ten (10) percent for carrying out inspection or maintenance activities. A permanent fifteen-foot wide vehicular access road within the easement(s) shall be provided around all SWM BMPS, such as ponds and infiltration structures. The access roads shall connect to a public thoroughfare. The access road (when applicable) will also provide access at a slope no greater than 20% to the bottom of all ponds and associated outlet structures. The access road shall be constructed ofe either gravel orp pavement andi maintained per the maintenance agreement. The Municipality reserves the right to alter the design of the access to any Vehicle ingress and egress and access roads are not required for SWM BMPS serving one Single Family Residential lot and located on the same lot they serve. 3. Maintenance Easements: A maintenance easement shall be provided which encompasses the stormwater facility and appurtenances and provides for access for maintenance purposes. The maintenance easement must be located atl least twenty (20) feet outside of the line ofi intersection of the 100-year water surface elevation and the ground surface for the stormwater facility and appurtenances. construction or continuation of a Stormwater problem area. structure. deepening, improving orp protecting such drainage facilities. SWM BMP. 28 4. Easements shall state that no trees, shrubs, structures, excavation, placement oft fill, or re-grading are tol be performed within the easement without written approval from the Municipality upon review by the Municipal Engineer. Upon approval of the Municipality, such landscaping may be placed in maintenance easements, providedit 5. Whenever practicable, easements shall be parallel to width and linked to property lines 6. Alle easement agreements shall be recorded with a reference to the recorded easement indicated on the site plan. The format and content of the easement agreement shall be does noti impede access. oft the subdivision. reviewed and approved by the Municipality and Solicitor. F. Inorder toj promote overland flow and infiltration, roof drains shall not discharge directly to streets or storm sewers. Roof drains may discharge directly to streets or storm sewers when deemed necessary by thel Municipality. Under no circumstances shall roof drains discharge G. Projects that have the potential to discharge into surface waters that have existing or designated HQ or EV uses (including EV wetlands), havei impairments due to stormwater, are connected to combined sewer systems, or have the potential to have an adverse effect on threatened or endangered species, or critical habitat for such species, are subject to additional BMP measures that must be considered and implemented for projects occurringi in these more directly to sanitary sewer systems. nvtonmenalysenstve areas: Table 307-1 Constructed wetlands s/Wet ponds Use where significant detention of peak flow rates isn needed and the contributing drainage area is large. May retrofit existing detention basins or Limited to park-and-ride sites and parking lots. temper peak runoff events through infiltration and/or discharge rate reduction. Storm sewer inlet structures or inserts are designed tor minimize the discharge of solids, floatables, and oillgrease pollutants. Regular maintenance oft these products isnecessary and is an important factor in assessing thet feasibility of using one of these construct new. Permeable pavement Manufactured products: Subsurface Subsurface storage products are designed to storage, water qualityi inlets, etc. products. 29 Proposed infiltration BMPS within two miles on either side of surface water supply areas or surface waters that have existing or designated HQ orE EV uses (including EV wetlands) must be designed and constructed to provide maximum pollutant removal priort to the runoff being infiltrated or discharged to 1. Zone A- Represents a 1/4 mile buffer on either side of ther river or stream extending from the area 1/4 mile downstream of thei intake upstream to thet five hourt time-of-travel (TOT) (Pennsylvania Department of Environmental Protection, 2006). 2. Zone B - Represents at two-mile buffer on either side oft the water body extending from the area 1/4 mile downstream oft the intake upstream to the 25 hour TOT. (Pennsylvania Department of Environmental Protection, 2006). 3. Zone C-T The remainder oft the watershed area (Pennsylvania Department of Environmental the receiving stream. PADEP defines thei following zones around such waters: Protection, 2006). H. Groundwater Supply Protection 1. Zone 1-7 Thei innermost protective zone: surrounding a well, spring, or existing infiltrative gallery. Zone 1ist the area within ar radius of 4001 feet around a community or public water supply source unless information is presented supporting a reduction oft this requirement. Proposed infiltration BMPS are notp permitted within Zone 1p protection areas (Pennsylvania 2. Zone 2-T The capture zone that encompasses the area of the aquifer through whichi its supplies watert to a well, spring, ore existing infiltration gallery. Zone 2is one-half mile radius arounda community or public water supply source unless more extensive hydrogeological testingi is done. Extreme care should be used wheni implementing! infitration BMPsi in Zone 2 areas. Pretreatment measures must be used toi filter and diminish pollutants (Pennsylvania 3. Zone 3- The area outside Zone 2t that contributes significant recharge tot the capture zone aquiferi in Zone 2( (Pennsylvania Department of Environmenta. Protection, 2006). Use of 4. Infiltration BMPS are not permitted within ar radius of 501 feet from a privately owned wells and water sources serving non-community supply systems (Pennsylvania Department of Department of Environmental Protection, 2006). Department of Environmental Protection, 2006). infiltration BMPs is not restricted. Environmental Protection, 2006) 30 ARTICLE IV- SWM SITE PLAN AND REPORT REQUIREMENTS Section 401. Plan and Report Contents A. All regulated activities that do noti fall under the exemption criteria referenced herein shall submit a SWM Site Plan and Report tot the municipality for review. These criteria shall apply to the total proposed development even if development is tot take place in stages. B. The following items shall bei included in the SWM Site Plan: 1. Appropriate sections from the Municipal SALDO and other applicable ordinances shall bei followed inj preparing the SWM Site Plans. Ini instances where the Municipality lacks Subdivision and Land Development regulations, the County SALDO shall be followed. 2. The SWM: Site Plan shall provide the following information: a. Unless specifically given written permission by the Municipality, thet following must be shown on the SWM Site Plan, prepared in at form which meets the requirements for recording in the County Office oft the Recorder of Deeds: Annotated maps, drawings, engineering plans, and construction details. Said plan shall be prepared by a Qualified Professional, with said preparer's seal andi registration number affixed tot the plan. Plans for tracts of less than twenty (20) acres shall be drawn at a scale of one inch equals no more than fifty (50) feet; for tracts of twenty (20) acres or more, plans shall be drawn at as scale of one inch equals no more than onel hundred (100) feet. Plans shall be submitted on the following sheet sizes: 18" X2 24",24'x3 36", or 36" X4 42".. AIl lettering shall be drawn to a size tol bel legible if the plans are reduced to half size. All sheets comprising a submission shall be on one size. The name oft the proposed development and the name and address of the owner oft the property and thei individual or firm preparing the plan. ii. Date of submission and revision, graphic scale, and North arrow. iv. Total tract boundary with distances marked to the nearest foot and bearings tot the nearest degree and the total acreage oft the tract. V. Key map (drawn to scale) showing all existing natural andr man-made features beyond the property boundary affected by the project and the extent of the watershed or sub-basin which drains through the project vi. Existing and proposed topographic contours shall be provided at intervals not greater than five (5) feet for existing and proposed site. conditions. 31 vii. Topographic contours ati intervals less than five (5) feet may be required forf flat sites, and to depict certain existing andi future stormwater management features. The reference datum used to develop topographic contours shall be stated on the plans. vii. Existing and proposed use, including the total area ofi impervious ix. Location and selected plant material used for vegetative filter paths to sinkholes, stream buffers, buffer yards, wetlands, streams, and other waters oft the Commonwealth, and the location of all notices to be posted, as specified in this Ordinance. Ifs stormwater management facilities are off-site, a note on the plan referring to location and agreements indicating responsibility for conveyance. to and maintenance oft the facilities; all such off-site facilities shall meet the design standards and criteria specified in this Ordinance, and details of the facilities shall bei included with the plan. surfaces after construction. b. An erosion and sediment pollution control plan, as prepared for and submitted C. Plan and profile, and construction detail drawings of all SWM BMPS including d. Locations ofe existing watercourses (including stream name per PAI DEP Chapter 93 designation, or otherwise noted as "unnamed tributary" with Chapter 93 numeric designation) and existing and proposed on-lot wastewater e. Locations of all access and maintenance easements, suitable for Recording. tot the County Conservation District. open channels andswales. facilities, water supply wells, andi infiltration areas. Signature blocks: The following signature block for thel Municipality: criteria of the applicable Municipal Ordinances." The following signature block for the Qualified Professional: on this date (date of signature), has reviewed this SWM Site Pian in accordance with the design standards and on this date (date of signature), hereby certify that this SWM Site Plan was prepared in strict accordance with all of the design standards and criteria of all applicable Municipal Ordinances." Thei following signature block for the Applicant/Owner: on this date (date of signature), has acknowledged that Iwe and/or mylour assigneesigrantees shall be responsible for maintenance oft the stormwater management system shown hereon, in accordance with approved stormwater management ownership and maintenance plan for this project, andt that such stormwater system shall 32 remain as a permanent fixture that cannot be altered, replaced, or removed g. Anote indicating that a copy oft the Recorded Record drawings will be submitted to thel Municipality by the Applicant's Registered Engineer for all stormwater facilities prior to occupancy, or the release oft the surety bond. The Municipality reserves the right to authorize the Municipal Engineer to review said Record Drawings, and to conduct independent measurements and without prior written approval from the Municipality." surveys. C. The following items shall bei included in the SWMI Report 1. The overall Stormwater management concept for the project. 2. Ad determination of Site Conditions in accordance with Appendix B. Ad 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. 3. Stormwater runoff design computations and documentation as specified in this Ordinance, or otherwise necessary to demonstrate that the maximum practicable measures havel been taken to meet the requirements oft this Ordinance, including the recommendations and general requirements in Section 301. All calculations shall be submitted to the Municipality on computation sheets for approval. Ifthe Municipality determines through review and independent computation that the size(s) of stormwater management facilities is insufficient, the Municipality may require the applicant to increase the size(s) of said stormwater management facilities. If the storm drainage system design is completed on a computer installation, sufficient supporting data shall be provided to allow comprehensive review by Municipal officials. 4. Expected project construction schedule. 5. The effect oft 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 6. Copies of all permits related to the SWM Site Plan required by the Pennsylvania Department of Environmental Protection, Pennsylvania Department of Transportation (PA DOT), and U.S. Army Corps of Engineers (USACOE) and other regulatory agencies. 7. The SWM: Site Plan shall include an operation and maintenance (0&M) plan for alle existing andp proposed physical stormwater management facilities. This plan shall address long-term ownership and responsibilities for operation and maintenance as well as schedules and 8. Hydrologic and hydraulic computations for alle existing and proposed stormwater 9. Construction specifications for SWM BMPS and storm drainage systems. 10. Each stormwater management report shall contain provisions that clearly set forth the ownership and maintenance responsibility of all permanent stormwater management, and the project site. costs for 0&M activities. management facilities and measures. erosion and sediment control facilities. Including: 33 a. Description of Maintenance Requirements. Officials, in accordance with this Article. b. Establishment of suitable easements for access to all facilities by Public Identification oft the responsible party ore entity for ownership andi maintenance of both temporary and permanent stormwater management facilities. In meeting this requirement, the following options are hereby provided for upon Facilities may bei incorporated within individual lots sot that the respective lot owners will own and be responsible for maintenance in accordance with recorded deed restriction. A description of the facility or system and the terms of the required maintenance shall be incorporated as part of the deed to the Ownership and maintenance may be the responsibility of al Property Owners Association. The stated responsibilities of the Property Owners Association in terms of owning and maintaining the stormwater management facilities shall be submitted with final plans for determination of their adequacy, and upon their approval shall be recorded with the approved subdivision plan among the County deed records. In addition, the approved subdivision plan and any deed written from said plan for a lot or lots shown herein shall contain a condition that its shall be mandatory for the owner or owners of said lot tol be members of d. For stormwater management facilities that are proposed as part of the site development plan, the applicant will be required to execute a developer agreement and a maintenance agreement with the Municipality for the construction and continued maintenance oft the facilities prior to the signature approval on the final plan. Access fori inspection by the municipality of all such facilities deemed critical to the public welfare at any reasonable time shall be e. Int the event the above priorities cannot be achieved, or where iti is required, the facilities may be dedicated to the Municipality in accordance with this Ordinance. Asa condition of Municipality acceptance of said facilities, the applicant shall provide fifteen (15) percent oft the cost ofi improvements, in the form ofa a maintenance bond, as estimated by the applicant's Qualified Professional, and approved by the Municipality, to cover contingency maintenance costs for eighteen (18) months from the date of stormwater management facilities acceptance of dedication. The fifteen (15) percent bond shall be based on the construction costs of the detention basin and outlet structure within the area dedicated to the municipality. approval by the Municipality. property. said Property Owners Association. provided. 11. Example Report Sections: Introduction Existing Site Conditions Models Existing Soils Information 34 Volume Mitigation Peak Rate Mitigation Description And Background Information Description And Background Information Pre-Development Conditions Post-Development Conditions StormwaterDetention Basin Hydraulics Storm Drain Design Peak-Rate Mitigation Results Effect of Project on Adjacent Properties Expected Project Construction Schedule Ownership and Maintenance Appendices Volume Mitigation Calculations, Worksheets And Information Peak Rate Mitigation Calculations And Information Water Quality' Worksheets And Information Precipitation Source Data Miscellaneous Computations Infiltration Rate Test Data General References SCSI Runoff Curve Numbers, Rational Runoff Coefficients, Manning'sc coefficients Construction Specifications for SWMI BMPS D. Small Project SWM Application 1. Refer to Appendix F. Section 402. Plan Submission A. Five (5) copies of the SWM Site Plan shall be submitted as follows: 1. Two (2) copies to the Municipality. 2. One copy to the Municipa! Engineer (when applicable) 3. One (1) copy to the County Planning Commission/Ofice B. Additional copies shall be submitted as requested by the Municipality. Section 403. Plan Review A. The SWM Site Plan shall be reviewed by the Municipality for consistency with the provisions of this ordinance. After review, thel Municipality will make the decision to approve or disapprove the SWM Site Plan. Ifthe SWM: Site Plan is disapproved upon review, the Municipality shall state the reasons for the disapproval in writing. The Municipality may also recommend approval oft the SWM Site Plan with conditions and, ifs so, shall provide the acceptable conditions for approval in writing. The SWM Site Plan review and recommendations shall be completed within thet time allowed by the Municipalities Planning Code for reviewing subdivision and land development plans. 35 B. The Municipality shall notify the applicant in writing within 45 calendar days whether the SWM Site Plan is approved or disapproved. If the SWMI Plan involves a Subdivision orl Land Development Plan, the notification period is 90 days. If al longer notification period is provided by other statute, regulation, or ordinance, the applicant will be SO notified by the Municipality. If the Municipality disapproves the SWM Plan, the Municipality shall cite the reasons for C. Thel Municipality's approval of a SWM Site Plan shall be valid for a period not to exceed five (5) years. This five-year period shall commence on the date that the Municipality signs the approved SWM Site Plan. If Stormwater management facilities included in the approved SWM Site Plan have not been constructed, or ifal Record Drawing of these facilities has not been approved within this five-year time period, then the Municipality may consider the SWM: Site Plan disapproved andr may revoke any and all permits. SWM Site Plans that are considered disapproved by the Municipality shall be resubmitted in accordance with this Ordinance. disapproval in writing. Section 404. Modification of Plans Amodification to a submitted SWM Site Plan thati involves a change in SWM BMPS or techniques, or that involves the relocation or re-design of SWMI BMPs, ort that is necessary because soil or other conditions are not as stated on the SWM Site Plan as determined by the Municipality, shall require a resubmission of the modified SWM Site Plani in accordance with this Article. Section 405. Resubmission of Disapproved SWM Site Plans Ad disapproved SWM Site Plan may be resubmitted, with the revisions addressing the Municipality's concerns, to thel Municipality in accordance with this Article. The applicable Review Fee must accompany a resubmission of a disapproved SWM Site Plan. Section 406. Record Drawings and Final Inspection A. The ApplicantDeveloper shall be responsible for completing Record Drawings of all SWM BMPS includedi in the approved SWM Site Plan. The Record Drawings and an explanation of any discrepancies with the design plans shall be submitted to the Municipality. B. The submission shall include a signed statement from a Qualified Professional verifying that all permanent SWM BMPS have been constructed according to the plans and specifications and C. After receipt of the signed statement and the Record Drawings by the Municipality, the Municipality may" conduct at final inspection. Sucht final inspection mayi include survey measurements by the Municipal Engineer to ensure conformance with the approved SWM Site Plan. The costs for such final inspection and surveys shall be included in the Fees and approved revisions thereto. Expenses in Section 601. 36 ARTICLE V- OPERATION AND MAINTENANCE Section 501. Responsibilities A. Thel Municipality shall make the final determination on the continuing maintenance responsibilities prior tot final approval oft the SWM Site Plan. Thel Municipality may require a dedication of such facilities as part oft the requirements for approval oft the SWM: Site Plan. Such a requirement isi not ani indication that thel Municipality will accept the facilities. The Municipality reserves the right to accept the ownership and operating responsibility for any or B. AlI SWMI BMPS shall be enumerated as permanent real estate appurtenances and recorded as The Operation and Maintenance Plan shall be recorded as a restrictive deed covenant that D. The Municipality shall take enforcement actions against an owner for any failuré to satisfy the the entire Stormwater management controls. deed restrictions. runs with the land. provisions oft this Article. Section 502. Operation and Maintenance Agreements The owneri is responsible for Operation and Maintenance of the SWMI BMP's, and for preparing an Operation and Maintenance Agreement in accordance with Appendix C. If the owner fails to adhere to the Operation and Maintenance Agreement, the Municipality may perform the services required and charge the owner appropriate fees. Non-payment off fees may result in al lien against the property. Section 503. Financial Guarantee A. When an approved SWM Site Plan requires the timely installation and proper construction of stormwater management controls, the Applicant shall provide al Financial Guarantee tot the Municipality equai to 110% oft the full construction cost of the required controis in accordance B. At the completion oft the project and as a prerequisite for the release oft the Financial with the Municipalities Planning Code. Guarantee, the Applicant shall: 1. Provide a certification of completion from an engineer, architect, surveyor or other qualified person, verifying that all permanent facilities have been constructed according to the SWM Site Plan & Report and approved revisions thereto. 3. Request at final inspection from the Municipality to certify compliance with this Ordinance, after receipt of the certification of completion and Record Drawings by the 2. Provide a set of Record Drawings. Municipality. 37 ARTICLE VA- Inspections Section 501A. Schedule of Inspections A. PA DEP ori its designees normally ensure compliance with any permits issued, including those for stormwater management. In addition tol PADEP compliance programs, the Municipality, the Municipal Engineer, and/or the Municipality's designee mayi inspect all phases oft the installation of temporary or permanent stormwater management facilities. The costs for such inspections shall be included in the Fees and Expenses in Section 601. B. During any stage of Earth Disturbance Activities, ift thel Municipality determines that the stormwater management facilities are not being installed in accordance with the approved SWM Site Plan, thel Municipality shall notify the Applicant and the Applicant shall take action to address the issue. Thel Municipality shall revoke any existing permits or approvals until the matter is addressed. In addition, the Municipality may require the Applicant to submit a revised C. After completion of construction, stormwater BMPS shall bei inspected by the landowner, or the landowner's designee according to thei inspection schedule described on the SWM Site Plan 1. The landowner shall submit copies of the inspection reports to the Municipality, ina D. The Municipality, the Municipal Engineer andlor the Municipality's designee may also conduct inspections oft the stormwater BMP's. The costs for such inspections shall bei included in the SWM Sitel Plan for review and approved as specified in this Ordinance. for each BMP. form stipulated by the Municipality. Expenses Covered by Fees in Section 601. Section 502A. Right-of-Entry A. Upon presentation of proper credentials, duly authorized representatives of the Municipality may enter at reasonable times, upon any property within the Municipality, to inspect the implementation, condition, or operations and maintenance of the stormwater BMPs in regard to B. Stormwater BMP owners and operators shall allow persons working on behalf of the Municipality ready access to all parts oft the premises for the purposes of determining . - Persons working on behalf of the Municipality shall have the right to temporarily locate on any stormwater BMP in thel Municipality such devices, as are necessary, to conductmonitoring: D. Unreasonable delay in allowing the Municipality access to a stormwater BMP is a violation of any aspect governed by this Ordinance. compliance with this Ordinance. andlor sampling oft the discharges from such stormwater BMP. this Ordinance. 38 ARTICLE VI- FEES AND EXPENSES Section 601. General The Municipality mayi include all costs incurred in the Review Fee charged to an Applicant. The Review Fee may include but not be limited to costs for thet following: A. Administrative/clenical processing. B. Review of the SWM Site Plan. C. Attendance atl Meetings. D. Inspections. E. Qualified Professional Review and Meeting Costs. F.F Recording Fees and Costs for Plan Reduction to Meet County Recording Requirements (f G. Final inspection upon completion oft the stormwater management facilities/BMPs and drainage improvements presented in the SWM Site Plan. Survey measurements oft the constructed H. Any additional work required to enforce any permit provisions regulated by this Ordinance, correct violations, and assure proper completion of stipulated remedial actions. Inspections of constructed stormwater management facilities by the Municipality, the Municipal Engineer andlor Municipal approval of the construction. The Municipal Engineer shall convert the future costs oft thesei inspections into a present worth. The Applicant shall deposit the present wroth sum of money with the Municipality to defray the costs of thei future inspections. required). facilities to confirm compliance with the approved SWM Site Plan. 39 ARTICLE VII-F PROHIBITIONS Section 701. Prohibited Discharges and Connections A. Any drain or conveyance, whether on the surface or subsurface, which allows any non- Stormwater discharge including sewage, process wastewater, and wash water to enter the B. No person shall allow, or cause to allow, discharges into surface waters oft this Commonwealth that are not composed entirely of stormwater, except (1) as provided in Subsection CI below C. Thet following discharges are authorized unless they are determined to be significant Waters oft this Commonwealth is prohibited. and (2) discharges allowed under a state or federal permit. contributors toj pollution of the Waters of this Commonwealth: Discharges from firet fighting activities fire hydrant flushing Irrigation drainage Air conditioning condensate Springs Water from crawl space pumps Flows from riparian habitats and wetlands Potable water sources including water line and Uncontaminated water from foundations ori from footing drains Lawn watering De-chlorinated swimming pool discharges Uncontaminated groundwater Water fromi individual residential car washing Pavement wash waters where spills or leaks of Routine external building wash down (which toxic or hazardous materials have not occurred does not use detergents or other compounds) (unless all spill material has been removed) and where detergents are not used D. Int the event that the Municipality or PA DEP determines that any of the discharges identified in Section 701.C, significantly contribute to pollution oft the Waters of this Commonwealth, the Municipality or PA DEP wil notify the responsibie person(s) to cease the discharge. Section 702. Roof Drains Roof drains and sump pumps shall discharge to infiltration or vegetative BMP's and to the maximum extent practicable to satisfy the criteria for Disconnected Impervious Areas (Appendix G). Section 703. Alteration of BMPs No person shall modify, remove, fill, landscape, or alter any SWM BMPS without the prior written approval oft the Municipality. 40 ARTICLE VIII - ENFORCEMENT AND PENALTIES Section 801. Right-of-Entry As a condition of approval of an Applicant's Stormwater management site plan, and upon presentation of proper credentials, the Applicant agrees that the Municipality, and/or their agents, may enter atr reasonable times upon any property within the Municipality toi inspect the condition oft the Stormwater structures and facilities concerning any aspect regulated by this Ordinance. Section 802. Inspection SWMI BMPs shall bei inspected by the land owner/developer (including Municipality for dedicated facilities) according to thei following list off frequencies: A. Annually for the first 5 years. B. Onceevery 3 years thereafter, C. During ori immediately after the cessation of a 10-year or greater storm. Section 803. Enforcement A. Itshall be unlawful for a person to undertake any Regulated. Activity except as provided in an B. Itshall be unlawful to alter, remove, or fail to implement any control structure required by the C. Compliance Inspections regarding implementation oft the SWM Site Plan are a responsibility of approved SWM Site Plan unless specifically exempted in Section 302. SWM Site Plan. the Municipality. 804. Suspension and Revocation A. Any approval for al Regulated Activity may be suspended or revoked by thel Municipality for: 1. Non-compliance with, or failure toi implement any provision of the approval, including Record Drawings and Operations and Maintenance Agreements. 2. Av violation ofa any provision of this Ordinance or any other applicable law, Ordinance, rule or 3. The creation of any condition or the commission of any act during the Regulated Activity which constitutes or creates al hazard or nuisance, pollution, or which endangers the life or property regulation relating to the Regulated Activity. ofothers. B. Asuspended approval may be reinstated by the Municipality when: 1. The Municipality has inspected and approved the corrections to the violations that 2. The Municipality is satisfied that the violation has been corrected. caused the suspension. 41 C. An approval that has been revoked byt thel Municipality cannot be reinstated. The Applicant may apply for an new approval under the provisions of this Ordinance. D. Ifa violation causes no immediate danger tol life, public health, or property, ati its sole discretion, the Municipality may provide al limited time for the owner to correct the violation. In these cases, thel Municipality will provide the owner, or the owner's designee, with a written notice oft the violation and the time allowed the owner to correct the violation. If the owner does not correct the violation within the allowed time, the Municipality may revoke or suspend any, ora all, applicable approvals and permits pertaining to any provision of this Ordinance. Section 805. Penalties A. Any person violating the provisions of this Ordinance may be assessed a civil penalty ofr not more than $300 for each violation, recoverable with costs. Each day thatt the violation continues constitutes a separate violation, and penalties shall be cumulative. B. Ina addition, the Municipality, mayi institute injunctive, mandamus or any other appropriate action or proceeding at law or in equity for the enforcement oft this Ordinance. Any court of competent jurisdiction shall have the right to issue restraining orders, temporary or permanent injunctions, mandamus or other appropriate forms ofr remedy or relief. C. The cost ofr removal, fine, and penalties hereinabove mentioned may be entered by the Municipality as al lien against such property, or properties of individual members ofa al Property Owners Association, in accordance with existing provisions ofl law. D. Ifthe Municipality determines at any time that any permanent stormwater management facility has been eliminated, altered, or improperly maintained, the Municipality shall advise the responsible party ofr required corrective measures, and shall provide said responsible party with as specific period toi implement the required corrective measures. Ifsuch action isr not taken by thep property owner, the Municipality may cause the work to be done and back-charge all costs to the property owners in accordance with this Ordinance. Section 806. Appeais A. Any person aggrieved by any action oft the Municipality ori its designee, relevant to the provisions of this Ordinance, may appeal to the Municipality within thirty (30) days oft that B. Any person aggrieved by any decision oft the Municipality, relevant to the provisions of this Ordinance, may appeal to the County Court Of Common Pleas in the county where the activity action. has taken place within thirty (30) days of the Municipality's decision. 42 ARTICLE IX - REFERENCES A. Pennsylvania Department of Environmental Protection. (DEP Doc. #363-0300-002 or current version). Pennsylvania Stormwater Best Management Practices Manual. Harrisburg, PA. B. Pennsylvania Department of Environmental Protection. 363-2134-008 (2000), as amended and updated. Erosion and Sediment Pollution Control Program Manual. Harrisburg, PA. C. United States Department of Agriculture (USDA), National Resources Conservation Service (NRCS). National Engineering Handbook. Part 630: Hydrology, 1969-2001. Originally published as the National Engineering Handbook, Section 4: Hydrology. Available online at: D. United States Department of Agriculture (USDA), Natural Resources Conservation Service (NRCS). 1986. Technical Release 55: Urban Hydrology for Small Watersheds, 2nd Edition. E. US Department of Commerce (USDC), National Oceanic and Atmospheric Administration (NOAA), National Weather Service (NWS), Hydrometeorological Design Studies Center. 2004- 2006. Plecptaton-Frequeny Atlas oft the United States. Atlas 14, Volume 2, Silver Spring, ntp/ww.wcenrsusdpR-techetnen-30hm Washington, D.C. Maryland, 20910. Internet address: ASASASASASINA Drainage Design Manual. F. United States Department of Department of Transportation (US DOT), Federal Highway Administration (FHA). 2001. Hydraulic Engineering Circular Number 22 (HEC-22), Urban G.F PennDOT Drainage Manual, Publication Number 584, as amended H. Philadelphia Water Department. 2006. Stormwater Management Guidance Manual. Section 4.2.2: Integrated Site Design. Philadelphia, PA. 43 ENACTED and ORDAINED at a regular meeting oft the Ridgway Borough Council ont this 21St day of March 2011. This Ordinance shall take effecti immediately. AaHb Doimil Cavdnt [Name][Title] S Mupey [Name][Title] Borough Manager -00 Name/[Tite) ATTEST: 19-9002 Secretary 44 APPENDIXA LOW IMPACT DEVELOPMENT PRACTICES ALTERNATIVE APPROACHES FOR MANAGING STORMWATER RUNOFF Natural hydrologic conditions may! be altered by development practices, which may create impervious surfaces, destroy drainage swales, construct storm sewers, and change local topography. A traditional approach to drainage has been to remove runoff from sites as quickly as possible and capture itin downstream detention basins. This approach leads tot the degradation of water quality as well as additional The recommended approach is to promote practices that will minimize post-development runoff rates and volumes and minimize needs for artificial conveyance and storage facilities. To: simulate pre-development hydrologic conditions, increasedi infiltration often is helpful to offset the effects ofi increasing the area of impervious surfaces. The ability toi increase infiltration depends upon the soil types and land use. Preserving natural hydrologic conditions requires careful site design that includes preservation of natural drainage features, minimization of impervious surfaces, reduction of hydraulic connectivity ofi impervious surfaces, and protection of natural depression storage areas. A well-designed site will contain ar mix ofa all expenditures for detaining and managing concentrated runoff. these features. Thet following describes various techniques to achieve this: A. Preserve Drainage Features. Protect natural drainage features, particularly vegetated drainage swales and channels. Locate streets and adjacent storm sewers away from valleys and B. Protect Natural Depression Storage Areas. Depression storage areas have no surface outlet, or they drain very slowly. Depressions shall be protected and the storage capacity shall be C. - Avoid Creating Impervious Surfaces. Reduce impervious surfaces to the maximum extent possibie. Buiding footprints, sidewaiks, driveways and other features shail be minimized. D. - Avoid Connecting Impervious Surfaces. Route roof runoff over lawns and avoid using storm sewers. Grade sites to increase the travel time of Stormwater runoff. Avoid concentrating E. Use Pervious-Paving Materials. Use pervious materials for driveways, parking lots, access roads, sidewalks, bike trails and hiking trails. Provide pervious strips between streets and F. Reduce Setbacks. Reduce setbacks for buildings to shorten the driveways and entry walks. G. Construct Cluster Developments. Construct Cluster Developments tor reduce street length per swales. incorporated into required detention facilities. runoff. sidewalks- lot. A-1 APPENDIX B A. LIST OF SITE CONDITIONS SUITABLE FOR INFILTRATION 1. Depth of bedrock below thei invert ofi infiltration BMPS shall be greater than or equal to 2. Depth of seasonal high water table below the invert ofi infiltration BMPs shall be 3. Soil permeability test results shall be greater than or equal to 0.10 inches/hour and 4. The appropriate factor of safety, per the existing soil conditions, and per the guidance provided per the! Pennsylvania Stormwater BMP Manual (current version) shall be 5. Methodologies and procedures for properly determining soil infiltration rates can be found within the Pennsylvania Stormwater Best Management Practices Manual. 6. Setback distances or buffers ofi infiltration BMPS shall be a minimum of: a. One hundred (100) feet from individual water supply wells andi from 2f feet. greater than or equal to 21 feet. less than or equal to 10 inches per hour. applied tot thet finali infiltration rate used for design. community or Municipal water supply wells. b. Twenty (20) feet from building foundations. C. Fifty (50) feet from septic system drain fields. fracture traces, faults, and pinnacles. d. Fifty (50) from karst geologic contacts such as sinkholes, closed depressions, e. Twenty (20) from the property line unless documentation is provided to show that all setbacks from wells, foundations and drain fields on neighboring properties will be met B. EFFECTIVE BMPS FOR INFILTRATION 1. Infiltration trench 2. Infiltration Basin/Sub-Surface Infiltration Bed 3. Bio Filters, Rain Gardens, Bio-Infiltration, Bio Swales 4. Filters for pre-treatment. 5. DryWellSeepage. Pits 6. Pervious Pavement/Concrete 7. Soil Amendments 8. Riparian Buffer Restoration C. EFFECTIVE BMPS FOR RATE CONTROL 1. Wet Ponds B-1 2. Stormwater Wetlands 3. Extended Detention (dry) Ponds 4. Vegetated Swales 5. Floodplain Restoration 6. Constructed Filters and re-vegetation. 1. Rain gardens 2. Green roofs 3. Constructed Wetlands 7. Runoff volume reduction BMPS listed and B and C above such as retention, infiltration D. EFFECTIVE BMPS FORBIO-RETENTION. ANDI EVAPOTRANSPRATION 4. Select, commercially available products (as approved by thel Municipality) Consult the Pennsylvania Stormwater Best Management Practices Manual for all available BMPS and stormwater technologies that can effectively mitigate stormwater runoff, volume, and quality issues. B-2 APPENDIX C OPERATION. AND MAINTENANCE AGREEMENT STORMWATER BEST MANAGEMENT PRACTICES THIS AGREEMENT, made and entered into this day of 20, bya and between. Ridgway, WITNESSETH records of (hereinafter Property"). (hereinafter the Landowner"), and Boroughof Elk County, Pennsylvania, (hereinafter Municipality"); WHEREAS, the Landowner is the owner of certain real property as recorded by deed in the land County, Pennsylvania, Deed Book at Page. WHEREAS, the Landowner is proceeding to build and develop the Property; and WHEREAS, the Stormwater management BMP Operation and Maintenance Plan approved byt the Municipality (hereinafter referred to as the "Plan") for the property identified herein, which is attached hereto as Appendix A and made part hereof, as approved by the Municipality, provides for management of Stormwater within the confines oft the Property through the use of Best Management Practices (BMPs); and WHEREAS, the Municipality, and the Landowner, his successors and assigns, agree that the health, safety, and welfare oft the residents oft the Municipality and the protection and maintenance of water quality require that on-site Stormwater Best Management Practices be constructed and maintained on the Property; and WHEREAS, the Municipality requires, through thei implementation oft the SWM Site Plan, that Stormwater management BMP's as required by said Plan and the Municipal Stormwater Management Ordinance be constructed and adequately operated and maintained by the Landowner, his successors and assigns. C-1 NOW, THEREFORE, in consideration of the foregoing promises, the mutual covenants contained herein, and thet following terms and conditions, the parties hereto agree as follows: 1. 2. 3. Thel Landowner shall construct the BMPs in accordance with the plans and specifications identified The Landowner shall operate and maintain the BMPS as shown on the Plani in good working order accordance with the specific maintenance requirements noted on the approved SWM Site Plan. The Landowner hereby grants permission to the Municipality, its authorized agents ande employees, to enter upon the property, at reasonable times and upon presentation of proper credentials, to inspect the BMPs whenever necessary. Whenever possible, the Municipality shall notify the Int the event the Landowner fails to operate and maintain the BMPS per paragraph 2, the Municipality ori its representatives may enter upon the Property and take whatever action is deemed necessary to maintain said BMP(s). This provision shall not be construed to allow the Municipality to erect any permanent structure on the land oft the Landowner. Iti is expressly understood and agreed that the Municipality is under no obligation to maintain or repair said facilities, andi in no event shall this Agreement be construed to impose any such obligation on the In the event the Municipality, pursuant to this Agreement, performs work of any nature, or expends any fundsi in performance ofs said work for labor, use ofe equipment, supplies, materials, and the like, the Landowner shall reimburse thel Municipality for all expenses (direct and indirect) incurred within The intent and purpose oft this Agreement is to ensure the proper maintenance of the onsite BMPS by the Landowner; provided, however, that this Agreement shall not be deemed to create or affect any additional liability of any party for damage alleged to result from or be caused by Stormwater The Landowner, its executors, administrators, assigns, and other successors in interests, shall release the Municipality from all damages, accidents, casualties, occurrences or claims which might arise or be asserted against said employees and representatives from the construction, presence, existence, or maintenance oft the BMP(s) by the Landowner or Municipality. The Municipality shall inspect the BMPS ata al minimum of once every three years to ensuret their in the SWM Site! Plan. Landowner prior to entering the property. 4. Municipality. 5. 10 days of receipt ofi invoice from the Municipality. 6. runoff. 7. 8. continued functioning. C-2 This Agreement shall be recorded at the Office oft the Recorder of Deeds of County, Pennsylvania, and shall constitute a covenant running with the Property and/or equitable servitude, and shall be binding on the Landowner, his administrators, executors, assigns, heirs and any other successors in interests, inj perpetuity. ATTEST: WITNESS the following signatures and seals: (SEAL) For the Municipality: (SEAL) For the Landowner: ATTEST: (City, Borough, Township) Pennsylvania County of , al Notary Public in and for the County and State aforesaid, whose commission expires on the. foregoing Agreement bearing date of the. GIVEN UNDER MY HAND THIS day of day of day of 20 do 20 has hereby certify that whose name(s) islare signed to the acknowledged the same before mei inr my said County and State. 200 NOTARY PUBLIC (SEAL) C-3 APPENDIX D 1 : 33 4 / 0 0 2 3 VAVASS D-1 APPENDIXE RELEASE RATE DISTRICT MAP E-1 APPENDIXF SMALL PROJECT SWM APPLICATION AND WORKSHEET F-1 Elk County Small Project Stormwater Management Application As required by the Municipality's Act 167 Stormwater Management Ordinance, a Small Project Stormwater Management Plani is required whenever more than 1,000 square feet of impervious surface is proposed. Impervious surfaces are areas that prevent the infiltration of water into the ground and shalli include, but not be limited to, roofs, patios, garages, storage sheds and similar structures, and any new streets or sidewalks. Table F-1 X To Calculate Impervious Surfaces Please Complete ThisTable Surface Type Building Driveway Parking Areas Patios/Walks Other Length Width = Proposed Surface Area Total Impervious Surface Area to be Managed (Sum of AllAreas) Smail Project SWM Application ift there is at threat to properly, health or safety. Ifthe Total Impervious Surface Area is LESS THAN 2,500 Square Feet: NOTE: The municipality can require the applicant to provide supplemental and additional information beyond the AStormwater Management Plan ISNOT required fort this regulated activity, please read and sign the Ifthe Total Impervious Surface. Area is GREATER THAN ORI EQUAL TO: 2,500 Square Feet: Complete the remainder oft the Application, including the Small Project SWMI Plan Worksheet. Property Owner Acknowledges that submission ofi inaccurate information may result in a stop work order or permit revocation. Acknowledgement of such is by signature below. declare thatl lam the owner or owner's legal representative. Ifurther acknowledge that the information provided is accurate and Municipal employees are granted access tot the above-described property for review andi inspection as may! ber required. Bys signature belowl acknowledge the requirements of Section 302.A, 302.B and 302.C of Ridgway Borough's Stormwater Management Ordinance, and hereby state that the Regulated Activity to be undertaken will comply with these Sections. acknowledgement below. F-2 :Owner Date: (Signature) (Print Name) F-3 Fort thel Proposed Impervious Surface, the following chart provides the required Capture Volume as well as the required surface area of chosen BMP's. The proposed Impervious Surface should ber rounded to the nearest 100 square feet. Table F-2 Required Surface Area of Proposed BMP Required Capture Volume (2'ximpervious Area) (Cubic Feet) 416.7 433.3 450.0 466.7 483.3 500.0 516.7 533.3 550.0 566.7 583.3 600.0 616.7 633.3 650.0 666.7 683.3 700.0 716.7 733.3 750.0 766.7 783.3 800.0 816.7 833.3 Proposed Impervious Area (Square Feet) 2,500 2,600 2,700 2,800 2,900 3,000 3,100 3,200 3,300 3,400 3,500 3,600 3,700 3,800 3,900 4,000 4,100 4,200 4,300 4,400 4,500 4,600 4,700 4,800 4,900 5,000 Sump or Trench2 2.5' Deep Aggregate (Square Feet) 500 520 540 560 580 600 620 640 660 680 700 720 740 760 780 800 820 840 860 880 900 920 940- 960 980 1,000 Rain Garden 2.0' Amended Soils (Square Feet) 521 542 563 583 604 625 646 667 688 708 729 750 771 792 813 833 854 875 896 917 938 958 979 1,000 1,021 1,042 25:1 Maximum Loading Ratio Governs thel Required Surface Area. Thisi is necessary to prevent compaction oft the underlying soils and thus reduce theiri infiltrative capacity over time (see current version of the PAD DEP BMP Manual) F-4 Small Project SWM Plan Worksheet- Instructions The Stormwater Management Ordinance developed through the Elk County Act 167 Stormwater Management Plan regulates compliance requirements for Stormwater Management int this jurisdiction. A complete copy of the ordinance can! be obtained by contacting the Elk County Planning Department. Regulated activities shall be conducted only after thel Municipality approves as stormwater management plan. The Elk County Act 167 Stormwater Management Plan will assist youi in preparing the necessary information and plans fort thel Municipality to review and approve. This document will constitute an approved plan ifall of the relevant components arei installed int their entirety AND no part of the stormwater system adversely affects any other property, nor adversely affect any septic systems or drinking water wells on this, or any other, parcel. Ifa an alternative system is to be used a plan willr need to bes submitted to the Municipality for approval. A design by a Qualified Professional may! be required for sites that are more complex. Construction details and materials for Stormwater BMPS can! bet found ini the PADEP Stormwater Management BMP (http:/www. depebsiatepausporalksenerplcommuntbes management practices manual/10631). All BMPS must be installed int their entirety AND the BMPS willl be located as not to adversely affect other property, norany Manual (current version) at: septic systems or drinking water wells on this, or any other, parcel. F-5 Small Project SWM Plan Worksheet PLEASE INITIAL BELOW TO INDICATE THE STORMWATER MANAGEMENT PLAN COMPONENTS FOR THIS SITE Tomeett this requirement, the following will bei installed and maintained: Required BMP Proposed Tributary Surface Area (#A) Impervious Area % ofTotal Impervious Area Small Project BMP Type From Table F-2) (#2) Rain Garden 6"F Ponding Depth; 2.0' Soil Depth Dry Well or Infiltration Trench 2.5 Aggregate Depth Sum of Total Value Must Equal: 100% Inl lieu of meeting the above, an alternative and/or professional design is attached for approval AND the system willl be located as not to adversely affect other property, any septic systems or drinking water wells on this, or any other, parcel. Site Sketch Plan showing: Property lines with dimensions Proposed buildings with dimensions Proposed impervious surfaces with Proposed septic system, ifa applicable Proposed well site, ifapplicable Proposed stormwater managements dimensions system(s) Operation and Maintenance. Agreement Condition on approval - The stormwater management plan must bei fullyi implemented prior to a request fori final inspection oft thel building or zoning permit. F-6 Acknowledgement By executing below, the Owner acknowledges thet following: Ideclare thatl lam the owner. of the property. Thei information providedi is accurate. review andi inspection as may ber required. Ifurther acknowledge thatr municipal representatives are! granted access to the above-described property for Property Owner Acknowledges that submission ofi inaccurate information may result in as stoplacknowledge the requirements of Section 302.A, 302.B and 302.C of Ridgway Borough's Stormwater Management Ordinance, and hereby state that the Regulated Activity to be undertaken will comply with these Sections. (Owner Signature) (Date) (Print Name) F-7 APPENDIXG DISCONNECTED IMPERVIOUS AREAS (DIA) G.1. Rooftop Disconnection When rooftop downspouts are directed to ap pervious area that allows fori infiltration, filtration, andi increased time of concentration, the rooftop may qualify as completely or partially DIA and a portion oft thei impervious rooftop arear may A rooftop is considered to be completely or partially disconnected ifiti meets the requirements listed below: The contributing area ofr rooftop to each disconnected discharge is 500 square feet or less, and The soil,i in proximity of the roof water discharge area, is not designated as hydrologic soil group' "D"or The overland flow path from roof water discharge area has a positive slope of 5% orl less. be excluded from the calculation oft total impervious area. equivalent, and For designs that meet these requirements, the portion oft the roof that may be considered disconnected depends on the length oft the overland path as designated in Table G.1. Table G.1 Partial Rooftop Disconnection Pervious Flow path Lengthi Roof Area Treated as Disconnected %of Contributing Area) 0 20 40 60 80 100 () 0-14 15-29 30-44 45-59 60-74 75+ 1- Flow path cannot include impervious surfaces and must be at least 15f feeti from anyi impervious surface. G.2. Pavement Disconnection When pavement runoffi is directed to a pervious area that allows fori infiltration, filtration, andi increased time of concentration, the contributing pavement arear may qualify as al DIA that may! be excluded from the calculation oft total impervious area. This applies generally only to small or narrow pavement structures such as driveways and narrow Pavement is disconnected ift the pavement, or area adjacent to the pavement, meets the requirements below: pathways through otherwise pervious areas (e.g., a walkway or bike path through ap park). The contributing flow path over impervious areai is not more than 751 feet, and Thel length of overland flow is greater than or equal to the contributing length, and The soili is not designated as hydrologic soil group' "D" ore equivalent, and The slope oft the contributing impervious areal is 5% or less, and The slope of the overland flow path is 5% or less. G-1 Ift the discharge is concentrated at one or more discrete points, no more than 1,000 square feetr may discharge to any one point. In addition, ag gravel strip or other spreading device is required for concentrated discharges. For non-concentrated discharges along thee edge of thep pavement, this requirement is waived; however, there must be a provision fort the establishment of vegetation along the pavement edge and temporary stabilization oft the area until vegetation becomes stabilized. REFERENCE Philadelphia Water Department. 2006.Stormwater Management Guidance Manual. Section 4.2.2: Integrated Site Design. Philadelphia, PA. G-2 APPENDIXH FEE REIMBURSEMENT AGREEMENT H-1 FEE REIMBURSEMENT AGREEMENT THIS AGREEMENT, made and entered into this Pennsylvania, (hereinafter ("Municipality"); day of 20 by and between, (hereinafter the Landowner), and the Borough of Ridgway, Elk County, WITNESSETH WHEREAS, thel Landowner is the owner of certain real property in the Borough of Ridgway (Municipality), as recorded by deed in the land records of Elk County, Pennsylvania, Deed Book. WHEREAS, thel Landowner is proceeding to build and develop the Property; and at Page. (hereinafter Property"). WHEREAS, thel Landowner has submitted a SWM Site Plan for review and approval by the Municipality (hereinafter WHEREAS, thel Developer has requested and/or required the Municipality approval and/or review ofi its proposed plans, and the Municipality is willing to authorize its professional consultants to review said Plan andlor proposal upon execution of this agreement, and upon deposit of an escrow account according tot the current Fee Schedule. NOW, THEREFORE, in consideration of thet foregoing promises, the mutual covenants contained herein, and the 1. Thel Landowner and Municipality hereby authorize and direct the Municipality's professional consultants, as defined at Section 107 of thel Pennsylvania Municipalities Planning Code tor review Landowner's plans or proposals to usei its property, and tor make such recommendations and specifications as may be necessary with respect to such plansi in accordance with all applicable Municipality ordinances, and State and Federal 2. The Landowner and Municipality acknowledge that the Municipality willi incur costs and fees relating to the review ofl Landowner's plans byi its professional consultants, and Landowner agrees to pay and/or reimburse 3. Thel Landowner shall pay the professional consultant's charges andi fees fort thei following: (a) review of any and all Stormwater Management Plans, studies, or other correspondence relating to the Landowners submission; (b) attendance at any and allr meetings relating to Landowner's plan; (c) preparation of any reports, legal documents, or other correspondence relating to Landowner's plan or proposal; (d) inspections during construction; (e) survey measurements and analyses of the constructed facilities for the purposes of ensuring compliance with the approved SWM Site Plan; ( administrative cost andi incurred expenses relating to the administration of this agreement; and (g)i inspections following completion ofo construction for aj period of 10 years. Itis understood by the execution of this agreement that thel Landowner specifically referred to as the' "Plan") fort the property identified herein; and following terms and conditions, the parties hereto agree as follows: rules and regulations. thei Municipaiity for such costsi in accordance with this agreement. accepts the Fee Schedule currently in effecti ini the Municipality. 4. The Landowner hereby agrees to deposit with the Municipality the sum of shall be held in anoninterest bearing account by thel Municipality. Dollars ($_ ), payable as cash in U.S. Dollars or check drawn on al Pennsylvanial bank to defray the costs of thet future inspections described in Paragraph 3(g) above, upon execution of this Agreement, which H-2 5. Thel Landowner hereby agrees to deposit with the Municipality the sum of Dollars ($ payable as cash in U.S. Dollars or check drawn on al Pennsylvania bank, as security for the payment of all costs and expenses, charges and fees as seti forthi in Paragraph 3(a) through 3(0) above, upone execution oft this agreement, which shall bel heldi in anoninterest- bearing account byt the Municipality. In thee event that the above deposited escrowi fund shall fall below fifty percent (50%) oft the original deposit, thel Landowner shall immediately, upon receipt of written notice from the Municipality ori its agent(s), deposit sums with the Municipality necessary to replenish the account to its original balance. Ini the event that thisi is insufficient to pay current Municipality incurred expenses, Landowner agrees top pay the total amount currently duet for Municipality incurred expenses without delayi in addition tor re-establishing the! base escrow account balance. The Municipality will usei its best efforts to advise thel Landowner of the impending likelihood thati its costs have exceeded the required escrow account sums as described above. 6. Landowner and Municipality agree that upon completion of construction and determination of the acceptability ofs such construction by the Municipality, all unused portions of the escrow account as described in Paragraph 5 above shall be returned tot the applicant upon written request to the Municipality. 7. Landowner and Municipality acknowledge that the Ordinance and appropriate fee schedules require Landowner to pay! Municipality's professional consultant fees relating to this plan or project, and ini the even that Landowner fails to provide sufficient funds int the above-described revolving escrow account upon fifteen (15) days written notice tot thel Landowner or make thei initial deposit payment described above within five (5) days of the date of this agreement, Landowner shall! bei in default oft this agreement andi in violation of the above Sections of Ordinance. Ini the event of Landowner's default as described above, the Municipality may refuse toi issue any permit or grant any approval necessary to further improve or develop the subject site until such time as thet terms of this Agreement are strictly met by Landowner. Moreover, final approval ori further review may! be denied or delayed until such time as thet terms of this agreement are 8. Landowner and thel Municipality further agree that all fees or costs arising out oft this Agreement shall be paid priort to thei issuance of any permit, occupancy or otherwise, for the use, improvement or construction of thel buildings as proposed on the Landowner's plan. The Landowner agrees and acknowledges that no permit, occupancy or otherwise, or recordable plans, shall ber released by thel Municipality until all outstanding professional consultant fees and costs are paidt to the Municipality, and provided thatt the 9. Thel Landowner may at any time terminate all further obligations under this Agreement by giving fifteen (15) days written notice toi the Municipality that it does not desire to proceed with the development: as set forth on the plan and upon receipt of such written noticel by the Landowner to thel Municipality, the Landowner shall bel liable to thel Municipality fori its costs and expenses incurred to the date and time ofi its receipt of the notice, plus the applicable administrative costs and expenses as outlined in Paragraph 3 above. 10. Thel Landowner and thel Municipality further agree that the Municipality shall have the right and privilege to sue thel Landowner or then property owneri in assumpsit for reimbursement or tol lien the property orb both, in itss sole discretion, for any expense in excess oft thet then current balance of funds on deposit with the Municipality in accordance with this agreement incurred byt the Municipality by reason of any review, supervision andi inspection of Landowner's project byi its professionals including, but not limited to, the Municipality Engineer and Solicitor. The Municipality's election ofi its remedies under this paragraph shall not 11. The Landowner and the Municipality acknowledge that this agreement represents their full understanding as strictly met by Landowner. Landowner is not in default under this agreement. constitute a waiver of any other remedies thel Municipality may have. to the Muniepaliysreimbusement forp professional or consultant services. H-3 12. This agreement shall bel binding on andi insure to the benefit oft the successors and assigns ofl Landowner. Thel Municipality shall receive thirty (30) days advance written notice from Landowner of any proposed assignment ofl Landowner's rights and responsibilities undert this Agreement. ATTEST: (SEAL) WITNESS thet following signatures and seals: For thel Municipality: For thel Landowner: Commonwealth of Pennsylvania County of Elk, Pennsylvania 3 SS: Ont this, the. personalily appeared day of 20 before met the undersigned officer, known toi me (or satisfactorily proven) tol be the person whose name subscribed to the within instrument, and acknowledges that executed the same for thep purpose therein contained. INWITNESS WHEREOF, Ihave hereunto set my hand and seal. My Commission Expires Official Title H-4 APPENDIXI ADDITIONAL ORDINANCE AND TECHNICAL GUIDELINES Attachment A-1 ADDITIONAL ORDINANCE. AND TECHNICAL GUIDELINES The use oft the Rational Formula to estimate peak discharges only from drainage areas that arel less than fiffy acres andi for storm sewer. sizing calculations, which are typically small in size may be used. For drainage areas fify acres or greater in size discharging to a storm drainage collection system, al more accurate methodology shall Inl lieu of using the data obtained from the NOAA, PFDS website, the use of alternate sources ofr rainfall data, including the PAL DOT Design Storm Curve values for Region 1,A per the most current version of the PA DOT Drainage Manual may be used. Forall full hydrograph calculations, arainfall duration of 24-hours shall be used and the Toi intercept stormwater runoff along streets at intervals reasonable relatedi to the extent and grade oft the area drained, and to prevent substantial flow ofv water across intersections ori flooded intersections during storms, designs shall comply with the procedures int the Pennsylvania Department of Transportation Design Manual Part 2. To6 ensure adequate and unimpeded flow ofs stormwater under driveways in, near, or across natural watercourses or drainage swales, suitable pipes or other waterways AlII lot and open areas shall be designed to drain to the nearest practical. street or drainage system, existing or proposed, as defined by the Municipal Engineer, with no impact on adjoining properties, unless an area specificaly designed for stormwater Swales shall be designed in accordance with Design of Roadside Channels with Flexible Linings, Hydraulic Engineering Circular No. 15 (US DOT, FHA). Deed restrictions may bei required on property (ies) containing drainage swaies and/or perennial streams. When required, these deed restrictions shall specify that no property owner obstruct or alter any drainage swale or perennial stream identified in Minimum storm. sewer diameter or equivalent diameter shall be 15 inches. Inlets shal, at a minimum, be located at the lowest point ofs street intersections to intercept the stormwater before it reaches pedestrian crossings; or at sag points of vertical curves in the street alignment that provide a natural point of ponding of Where special land requirements exist, special inlets may be used. The interval between inlets collecting stormwater, runoffs shall be determined in accordance with the Pennsylvania Department of Transportation Design Manual Part 2, DM-2, Chapter 10, Section 5' Capacity of Waterway Areas," "or Urban Drainage be used. distribution type shall be Type-ll, per TR-55. DM-2, Chapter 10 (PADOT). shall be provided as necessary. detention is provided. the stormwater management, plan. surface stormwater. Design Manual (HEC22, USDOT, FHA). Attachment A-2 In curbed sections, the maximum encroachment ofv water ont the roadway pavement shall not exceed half ofa a through traffic lane or one (1)i inch less than the depth of curb during the 10j year design storm off five (5) minute duration. Inlets shall be provided tol limit the encroachment ofv water ont the pavement. When inlets are used in a storm system within the right-of-way limits ofa street inl lieu ofr manholes, the spacing of such inlets shall note exceed the maximum distance off four hundredi fifly The design ofs storm inlets shall be in accordance with Drainage of Highway Pavements, Hydraulic Engineering Circular Number 12, (USDOT, FHA). (450) feet. Bridges and culverts Bridges and culverts shall have ample waterway to carrye expected flows based on the following minimum storm frequencies: 10 year for driveways; 25) year for local streets; 50 year for collector streets; and 100 yeart for arterials; or as required by the Municipal Bridge and/or culvert construction shall be in accordance with the Pennsylvania The design criteria contained ini this Article are intended for use. in conjunction with the Chapter 105 Regulations of the Pennsylvania Department of Environmental Protection APA DEP permit ina accordance with Chapter 105 shall be required for any obstruction ore encroachment ini the regulated waters of the Commonwealth, priort to the approval oft the SWMI Plan. Alla areas oft the Municipality shall be classified as rural, suburban, or urban, as determined by the Municipality (See PA DEP Section 105.161) for bridge and culvert designs. Ini the event any question or conflict arises between this Article andi the PA DEP Chapter 105 Regulations, the design criteria contained in Engineer. Department of Transportation specifications. entitled, "Water Obstructions and Encroachments". the PAL DEP regulations shall govern. Stormwater Management Facilities: Any Stormwater management facility (e.g., detention basin) designed to store runoff andi requiring a berm or earthen embankment. required or regulated by this Ordinance shall be designed to provide an emergency: spillway to handle flow up to and including the 100-year proposed conditions andi may be subject to PA DEP Chapter 105 regulations. Facilities requiring berms or earthen embankments shalli include the construction of anti-seep collars along the length oft the outlet barrel and containing the proposed phreatic line. Anti-seep collars should be designed in accordance with Stormwater management facilities shall be installed prior to or concurrent with any earthmoving or land disturbances which they will serve. Earthen embankments and berms shall be constructed using 6" soil lifts and compacted with the use of the PA DEP Erosion Control Manual. Attachment A-3 sheepsfoot roller equipment. The design of all Stormwater management facilities over limestone formations shall include measures to prevent groundwater contamination and, where required, sinkhole formation. Soils used for the construction of Stormwater management facilities shall have moderate tol low erodibility factors (ie. "K" factors of0.32 or less). Outlet structures within etention/retention/wet basins shall incorporate childproof, non-clogging trash racks or grates over all horizontally oriented openings. All vertically oriented openings over twelve (12) inches or larger in any dimension where entry bya child could cause injury or death shall be covered with childproof, non-clogging trash racks, except where. such openings carry perennial stream flows. Design openings less than six (6) inches in any dimension shall be covered with a pipe screen. Measures to completely drain detention/retention basins in the event of clogging oft the primary design opening(s) shall be incorporated into the design of basin outlet structures. Basin outlet pipes shall have a minimum inside diameter of fifteen (15) inches or a cross-sectional area of one hundred seventy-six (176) square inches, except that pipes under ai twenty-five foot or greater fill shall not be less than twenty- four (24) inches ora cross-sectional area off four hundred fity-three (453) square Outleta aprons shall be designed and shall extend at a minimum toi the toe oft the basin slope. Where spillways will be usedt to manage peak discharges in excess oft the 10- year storm, such spillways shall be constructed to withstand the pressures of impounded waters and convey flows at computed outlet velocities without erosion. Energy dissipaters andlor level spreaders shall be installed at points where pipes or drainageways discharge to ort from Stormwater management: facilities. Stormwater management. facilities shall be constructed with an appropriate sedimentation forebay Stormwater management facilities shall be designed to release their total volumes inches, and shall consist ofr reinforced concrete. and al low-flow channel at a minimum slope of 1% detained within the following maximum time periods: Roofs and Parking Lots 241 hours. Detention Basin- 48 hours. Infiltration Facilities 72 hours. The intermittent treatment of wetlands/wet basins with commercially available products designed to curtail the breeding habitats ofn mosquitoes and other invasive insects may be permitted at the discretion oft the Municipality. Publications from the PA Department of Health and the Penn State Cooperative Extension concerning West Nile Virus identify aggressive public education about the risks posed by standing water in artificial containers (tires, trash cans, rain gutters, bird baths) as the most effective method to control vector mosquitoes. Stream Buffers Attachment A-4 Stream Buffers shall be providedi for new development sites using the following A minimum stream buffer width of 501 feet landwardi in each direction from the topo of stream banks is required for all waterways having both a defined bank anda a A minimum stream buffer width of 35f feet landward in each direction from the centerline oft the waterway is requiredi fors smaller waterways having a contributing watershed area ofl less than 100 acres and greater than 10 acres. The stream buffer area shall be maintained in a natural state. requirements: contributing watershed. area of greater than 100 acres. When wetland(s) extend beyond the edge oft the required buffer width, the buffer shall be adjusted. sO that the buffer consists oft the extent oft the wetland plus a 25-foot zone Stream buffer averaging may be appliedi to account for encroachments such as road crossings. The following criteria must be met in order to use buffer averaging ona Buffer averaging is requiredi for water quality buffers that have stream crossings. An overall average buffer width ofa at least 50 feet must be achieved within the boundaries of the property to be developed. Stream buffer corridors on adjoining properties cannot be included with buffera averaging onas separate property, eveni if The average width must be calculated based upon the entire length ofs stream bank that is located within the boundaries oft the property to be developed. When calculating the buffer length, the natural. stream channel. shall be followed. Stream buffer averaging shall be applied to each side of a stream independently. If the property being developed encompasses both sides ofa a stream, buffer averaging can be applied to both sides oft the stream, but must be applied to both sides of the The total width of the buffer shall not bei less than 25 feet at any location, except at approved. stream crossings. Those areas oft the buffer having a minimum width of25 feet (or less at approved. stream crossings) can comprise no more. than 50 percent of Stream buffer locations and widths. shall be shown on all subdivision plans with notations requiring that they be maintained. in a natural state. Stream buffers shall be shown on allg grading ande erosion and sedimentation control plans. The defined. stream buffer location. shall be properly recorded. The recording shall provide a plan illustrating the stream buffer location, width and the requirement When there is a conflict between the buffer requirements in this ordinance and any other municipal ordinance, the more restrictive standard. shall apply. In ordert to promote overland flow andi infiltration, roof drains shall not discharge directly to streets or storm sewers. Roof drains may discharge directly to. streets or storm sewers when deemed necessary by the Municipality. Under no circumstances extending beyond the wetland edge. development site: owned by the same property owner. stream independently. the buffer length. that it be maintained ina a natural state. Attachment A-5 shall roof drains discharge directly tos sanitary sewer systems. Stormwater drainage systems shall be provided to permit unimpeded flow along natural watercourses; except as modified by stormwater managementi facilities or Areas of existing diffused drainage discharge shall be subject to any applicable discharge criteria ini the general direction of existing discharge, whether proposed to be concentrated or maintained as diffused drainage areas, except as otherwise provided by this ordinance. Ifdiffused flow is proposed to be concentrated and discharged onto adjacent property, the Applicant must document that adequate downstream conveyance facilities exist to safely transport the concentrated discharge, or otherwise prove that no erosion, sedimentation, flooding or other harm will result Where a development. site is traversed by watercourses, drainage easements. shall be provided conforming to the line ofs such watercourses. The terms oft the easement shall prohibit excavation, the placing off fill or structures, and any alterations that may adversely affect the flow ofs stormwater within any portion of the easement. In addition, maintenance, including mowing of vegetation within the easement shall be required, When. it can be shown that, due to topographic conditions, natural drainageways on the site cannot adequately provide for drainage, open channels may be constructed conforming substantially to thel line and grade ofs such natural drainageways. Work within natural drainageways shall be subject to approval by PAI DEP through the Joint Permit Application process, or, where deemed appropriate by PA DEP, through the open channels consistent with this Ordinance. from the concentrated discharge. except as approved by the appropriate governing authority. General Permit process. Sinkhole Protection: Stormwater from roadways, parking lots, storm sewers, roof drains, or other concentrated stormwater runoff paths shall not be discharged directly into. sinkholes. To, protect. sensitive Karst areas, the Municipal Engineer may require basins to contain an impervious liner. The liner may be of the impervious membrane type, placed in accordance with the manufacturer's recommendations, or an approved alternative as approved by the Municipal Engineer. Attachment A-6