ACCELERATED EROSION - the removal of the surface of the land through the combined action of man’s activity and the natural processes of a rate greater than would occur because of the natural process alone.
ACT 167 - the Act of October 4, 1978, P.L. 864, No. 167, 32 P.S. §680.1 et seq., as amended, and as may be amended in the future.
AGRICULTURAL ACTIVITIES - the work of producing crops and raising livestock including tillage, plowing, disking, harrowing, pasturing and installation of conservation measures. For purposes of regulation by this Part construction of new buildings or impervious area is not considered an agricultural activity.
ALTERATION - as applied to land, a change in topography as a result 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 more or less impervious; land disturbance.
APPLICABLE ACT 167 PLAN - the Brodhead Creek Plan or the Delaware River Plan, depending on the watershed in which the parent tract is located.
APPLICANT - a person who has filed an application for approval to engage in any regulated activities as defined in §204 of this Part.
AS-BUILT DRAWINGS - those maintained by the contractor as he constructs the project and upon which he documents the actual locations of the building components and changes to the original contract documents. These, or a copy of same, are turned over to the Engineer at the completion of the project.
BANKFULL - the channel at the top-of-bank or point where water begins to overflow onto a floodplain.
BASE FLOW - the portion of stream flow that is sustained by ground water discharge.
BIORETENTION - a stormwater retention area which utilizes woody and herbaceous plants and soils to remove pollutants before infiltration occurs.
BMP (BEST MANAGEMENT PRACTICE) - stormwater structures, facilities and techniques to control, maintain or improve the quantity and quality of surface runoff and groundwater recharge.
BOARD OF SUPERVISORS - the governing body of the Township.
BRODHEAD CREEK PLAN - the Brodhead/McMichael Creeks Watershed Stormwater Management Plan approved by the Board of Commissioners of Monroe County, Pennsylvania, in December, 2005, and approved by DEP.
BUFFER - the area of land immediately adjacent to any wetland, lake, pond, vernal pond, or stream, measured perpendicular to and horizontally from the delineated edge of the wetland, lake, pond, or vernal pond, or the top-of-bank on both sides of a stream.
CHANNEL EROSION - the widening, deepening, and headword cutting of small channels and waterways, caused by stormwater runoff or bankfull flows.
CHAPTER 102 - Chapter 102, “Erosion and Sedimentation Control,” of Title 25, rules and regulations of the DEP.
CHAPTER 105 - Chapter 105, “Water Obstructions and Encroachments,” of Title 25, rules and regulations of the DEP.
CHAPTER 106 - Chapter 106, “Floodplain Management,” of Title 25, rules and regulations of the DEP.
CISTERN - an underground reservoir or tank for storing rainwater.
CONSERVATION DISTRICT - the Monroe County Conservation District.
CONSUMPTIVE WATER USE - that part of water removed from the immediate water environment not available for other purposes such as water supply, maintenance of stream flows, water quality, fisheries and recreation, as opposed to water that is used nonconsumptively, which is returned to surface water, where practicable, and groundwater.
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 of impounding or storing water or another fluid or semifluid, or a refuse bank, fill or structure for highway, railroad or other purposes which does or may impound water or another fluid or semi fluid.
DELAWARE RIVER PLAN - the watershed stormwater management plan for the Delaware River Watershed approved by the Board of Commissioners of Monroe County and DEP Until such time as the Board of Commissioners of Monroe County and DEP approve such a watershed stormwater management plan, the provisions of the Brodhead Creek Plan shall be considered the Delaware River Plan.
DEP - the Pennsylvania Department of Environmental Protection or any agency successor thereto.
DESIGNEE - the agent of the Monroe County Planning Commission, Conservation District and/or agent of the Board of Supervisors involved with the administration, review or enforcement of any provision of this Part by contract or memorandum of understanding.
DESIGN PROFESSIONAL - a Pennsylvania registered professional engineer, registered landscape architect or a registered professional land surveyor trained to develop stormwater management plans.
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 evaluation of stormwater management systems.
DETENTION BASIN - an impoundment structure designed to manage stormwater runoff by temporarily storing the runoff and releasing it at a predetermined rate.
DETENTION DISTRICT - those subareas in which some type of detention is required to meet the requirements of the applicable Act 167 Plan and the goals of Act 167.
DEVELOPMENT SITE - the specific tract of land for which a regulated activity is proposed.
DIFFUSED DRAINAGE DISCHARGE - drainage discharge not confined to a single point location or channel, such as sheet flow or shallow concentrated flow.
DISTURBED AREAS - land area where an earth disturbance activity is occurring or has occurred.
DOWNSLOPE PROPERTY LINE - that portion of the property line of the lot, tract, or parcels of land being developed located such that overland or pipe flow from the site would be directed towards it.
DRAINAGE CONVEYANCE FACILITY - a stormwater management facility designed to transmit stormwater runoff and shall include channels, swales, pipes, conduits, culverts, storm sewers, etc.
DRAINAGE EASEMENT - a right granted by a grantor to a grantee, allowing the use of private land for stormwater management purposes.
DRAINAGE PERMIT - a permit issued by the Township after the drainage plan has been approved.
DRAINAGE PLAN - the documentation of the stormwater management system, if any, to be used for a given development site, the contents of which are established in §233.
EARTH DISTURBANCE - a construction or other human activity which disturbs the surface of land, including, but not limited to, clearing and grubbing, grading, excavations, embankments, agricultural plowing or tilling, timber harvesting activities, road maintenance activities involving subbase disturbance, mineral extraction, and the moving, depositing, stockpiling, or storing of soil, rock or earth materials.
EMERGENCY SPILLWAY - a conveyance area that is used to pass peak discharge greater than the maximum design storm controlled by the stormwater facility.
ENCROACHMENT - a structure or activity that changes, expands or diminishes the course, current or cross section of a watercourse, floodway or body of water.
EROSION - the movement of soil particles by the action of water, wind, ice, or other natural forces.
EROSION AND SEDIMENT CONTROL PLAN - a site specific plan that is designed to minimize accelerated erosion and sedimentation during construction.
EXCEPTIONAL VALUE WATERS - surface waters of high quality which satisfy Pennsylvania Code, Title 25, “Environmental Protection,” Chapter 93, “Water Quality Standards,” §93.4b(b) (relating to anti-degradation).
EXISTING CONDITIONS - the initial condition of a project site prior to the proposed alteration. If the initial condition of the site is undeveloped land, the land use shall be considered as “meadow” unless the natural land cover is proven to generate lower curve numbers or Rational “C” value.
FLOOD - a temporary condition of partial or complete inundation of land areas from the overflow of streams, rivers, and other waters of this Commonwealth.
FLOODPLAIN - any land area susceptible to inundation by water from any natural source or delineated by applicable Department of Housing and Urban Development, Federal Insurance Administration.
FLOOD HAZARD BOUNDARY - mapped as being a special flood hazard area.
FLOODWAY - the channel of the watercourse and those portions of the adjoining floodplains, which are reasonably required to carry and discharge the one hundred (100) year frequency flood. Unless otherwise specified, the boundary of the 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 frequency floodway, it is assumed - absent evidence to the contrary - that the floodway extends from the stream to fifty (50) feet from the top of the bank of the stream.
FOREST MANAGEMENT/TIMBER OPERATIONS - planning and activities necessary for the management of forest land with no change of land use proposed. These include timber inventory and preparation of forest management plans, silvicultural treatment, cutting budgets, logging road design and construction, timber harvesting and reforestation.
FREEBOARD - a vertical distance between the elevation of the design high-water and the top of a dam, levee, tank, basin, swale, or diversion berm. The space is required as a safety margin in a pond or basin.
GRADE - a slope, usually of a road, channel or natural ground specified in percent and shown on plans as specified herein.
(TO) GRADE - to finish the surface of a roadbed, top of embankment or bottom of excavation.
GRASSED WATERWAY - a natural or constructed waterway, usually broad and shallow, covered with erosion-resistant grasses, used to convey surface water.
GROUNDWATER RECHARGE - replenishment of existing natural underground water supplies without degrading groundwater quality.
HEC-HMS - the U.S. Army Corps of Engineers, Hydrologic Engineering Center (HEC) - Hydrologic Modeling System (HMS) computer program.
HIGH QUALITY WATERS - surface waters having quality which exceeds levels necessary to support propagation offish, shellfish, and wildlife and recreation in and on the water by satisfying Pennsylvania Code, Title 25, “Environmental Protection,” Chapter 93, “Water Quality Standards,” §93.4b(a).
HYDROLOGIC REGIME (NATURAL) - the hydrologic cycle or balance that sustains quality and quantity of stormwater, baseflow, storage, and groundwater supplies under natural conditions.
HYDROLOGIC SOIL GROUP - a classification of soils by the NCRS into four (4) runoff potential groups. The groups range from A soils, which are very permeable and produce little runoff, to D soils, which are not very permeable and produce much more runoff.
IMPERVIOUS SURFACE - a surface that prevents the percolation of water into the ground such as rooftops, pavement, sidewalks, driveways, gravel drives, roads and parking, and compacted fill, earth or turf to be used as such.
IMPOUNDMENT - a retention or detention basin designed to retain stormwater runoff and release it at a controlled rate.
INFILL - development that occurs on smaller parcels that remain undeveloped but are within or very close proximity to urban areas. The development relies on existing infrastructure and does not require an extension of water, sewer or other public utilities.
INFILTRATION - for stormwater to pass through the soil from the surface. The entrance of surface water into the soil, usually at the soil/air interface.
INFILTRATION STRUCTURES - a structure designed to direct runoff into the underground water (e.g., French drains, seepage pits, seepage trench).
INLET - the upstream end of any structure through which water may flow.
LIMITING ZONE - a soil horizon or condition in the soil profile or underlying strata which includes one of the following:
A. A seasonal high water table, whether perched or regional, determined by direct observation of the water table or indicated by soil mottling.
B. A rock with open joints, fracture or solution channels, or masses of loose rock fragments, including gravel, with insufficient fine soil to fill the voids between the fragments.
C. A rock formation, other stratum or soil condition which is so slowly permeable that it effectively limits downward passage of water.
LOT - a part of a subdivision or a parcel of land used as a building site or intended to be used for building purposes, whether immediate or future, which would not be further subdivided.
MAIN STEM (MAIN CHANNEL) - any stream segment or other runoff conveyance facility used as a reach in the Brodhead Creek Plan hydrologic model.
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 of flow and slope. “Open channels” may include closed conduits so long as the flow is not under pressure.
MPC - the Pennsylvania Municipalities Planning Code, Act of July 31, 1968, P.L. 805, No. 247, as amended and reenacted, 53 P.S. §10101 et seq.
NATURAL HYDROLOGIC REGIME - (see “hydrologic regime”).
NONPOINT SOURCE POLLUTION - pollution that enters a water body from diffuse origins in the watershed and does not result from discernible, confined, or discrete conveyances.
NONSTRUCTURAL BMPS - methods of controlling stormwater runoff quantity and quality, such as innovative site planning, impervious area and grading reduction, protection of natural depression areas, temporary ponding on site and other techniques.
NRCS - Natural Resource Conservation Service (previously SCS).
OPEN CHANNEL - a drainage element in which stormwater flows within an open surface. Open channels include, but shall not be limited to, natural and man-made drainage ways, swales, streams, ditches, canals, and pipes flowing partly full.
OUTFALL - point where water flows from a conduit, stream, or drain.
OUTLET - points of water disposal from a stream, river, lake, tidewater or artificial drain.
PARENT TRACT - for land within the Brodhead Creek Watershed, the parcel of land from which a land development or subdivision originates existing as of May 1, 1994. For land within the Delaware River Watershed, the parcel of land from which a land development or subdivision originates existing as of October 12, 2006.
PARKING LOT STORAGE - involves 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.
PENNDOT - the Pennsylvania Department of Transportation or any agency successor thereto.
PENN STATE RUNOFF MODEL (CALIBRATED) - the computer-based hydrologic modeling technique adapted to the applicable Act 167 Plan. The model has been “calibrated” to reflect actual recorded flow values by adjoining key model input parameters.
PIPE - a culvert, closed conduit, or similar structure (including appurtenances) that conveys stormwater.
PLANNING COMMISSION - the Township Planning Commission.
PMF - PROBABLE MAXIMUM FLOOD - the flood that may be expected from the most severe combination of critical meteorologic and hydrologic conditions that are reasonably possible in any area. The PMF is derived from the probable maximum precipitation (PMP) as determined based on data obtained from the National Oceanographic and Atmospheric Administration (NOAA).
PRACTICABLE ALTERNATIVE - an alternative that is available and capable of being done after taking into consideration cost, existing technology and logistics in light of overall project purposes.
PREDEVELOPMENT - undeveloped/natural condition.
PRETREATMENT - techniques employed in structural and nonstructural stormwater BMPs to provide storage or filtering to help trap coarse materials and other pollutants before they enter the system, but not necessarily meet the water quality volume requirements of §223.
RATIONAL FORMULA - a rainfall-runoff relation used to estimate peak flow.
RECHARGE AREA - undisturbed surface area or depression where stormwater collects, and a portion of which infiltrates and replenishes the underground and groundwater.
RECORD DRAWINGS - original documents revised to suit the as-built conditions and subsequently provided by the engineer to the client. The engineer takes the contractor’s as-builts, reviews them in detail with his/her own records for completeness, then either turns these over to the client or transfers the information to a set of reproducibles, in both cases for the client’s permanent records.
REDEVELOPMENT - any construction, alteration, or improvement exceeding 5,000 square feet of impervious surface on sites where existing land use is commercial, industrial, institutional, or multifamily residential.
REGULATED ACTIVITIES - actions or proposed actions that have an impact on stormwater runoff quality and quantity and that are specified in §205 of this Part.
RELEASE RATE - the percentage of existing conditions peak rate of runoff from a development site or subarea to which the post development peak rate of 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 do not have an outlet other than recharge and must infiltrate stored water in no more than four (4) days.
RETURN PERIOD - the average interval, in years, within which a storm event of a given magnitude can be expected to recur.
RISER - a vertical pipe extending from the bottom of a pond that is used to control the discharge rate from the pond for a specified design storm.
ROOFTOP DETENTION - temporary ponding and gradual release of stormwater falling directly onto flat roof surfaces by incorporating controlled-flow roof drains into building designs.
RUNOFF - any part of precipitation that flows over the land surface. SALDO - the Township Subdivision and Land Development Ordinance [Chapter 22].
SEDIMENT BASIN - a barrier, dam, retention or detention basin located and designed to retain rock, sand, gravel, silt, or other material transported by water during construction.
SEDIMENT POLLUTION - the placement, discharge or any other introduction of sediment into the waters of the Commonwealth.
SEDIMENTATION - the process by which mineral or organic matter is accumulated or deposited by the movement of water or air.
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 underground water.
SHEET FLOW - runoff that flows over the ground surface as a thin, even layer.
SOIL-COVER COMPLEX METHOD - a method of runoff computation developed by the NRCS that is based on relating soil type and land use/cover to a runoff parameter called curve number (CN).
SOURCE WATER PROTECTION AREAS (SWPA) - the zone through which contaminants, if present, are likely to migrate and reach a drinking water well or surface water intake.
SPECIAL PROTECTION SUBWATERSHEDS - watersheds for which the receiving waters are exceptional value (EV) or high quality (HQ) waters.
SPILLWAY - a conveyance that is used to pass the peak discharge of the maximum design storm controlled by the stormwater facility.
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 a function of storage volume and depth.
STORM FREQUENCY - the number of times that a given storm “event” occurs or is exceeded on the average in a stated period of years. See “return period.”
STORM SEWER - a system of pipes and/or open channels that convey intercepted runoff and stormwater from other sources, but excludes domestic sewage and industrial wastes.
STORMWATER - the surface runoff generated by precipitation reaching the ground surface.
STORMWATER MANAGEMENT FACILITY - any structure, natural or man-made, that, due to its condition, design, or construction, conveys, stores, or otherwise affects stormwater runoff quality and quantity. Typical stormwater management facilities include, but are not limited to, detention and retention basins, open channels, storm sewers, pipes, and infiltration structures.
STREAM - a natural watercourse.
STREAM ENCLOSURE - a bridge, culvert or other structure in excess of one hundred (100) feet in length upstream to downstream which encloses a regulated water of this Commonwealth.
SUBAREA (SUBWATERSHED)- the smallest drainage unit of a watershed for which stormwater management criteria have been established in the applicable Act 167 Plan.
SWALE - a low lying stretch of land which gathers or carries surface water runoff.
TIMBER OPERATIONS - see “forest management.”
TIME-OF-CONCENTRATION (TC) - the time for surface runoff to travel from the hydraulically most distant point of the watershed to a point of interest within the watershed. This time is the combined total of overland flow time and flow time in pipes or channels, if any.
TOWNSHIP - Smithfield Township, Monroe County, Pennsylvania.
WATERCOURSE - a channel or conveyance of surface water having defined bed and banks, whether natural or artificial, with perennial or intermittent flow.
WATERS OF THE 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 and underground water, or parts thereof, whether natural or artificial, within or on the boundaries of this Commonwealth.
WELLHEAD - the point at which a groundwater well bore hole meets the surface of the ground.
WELLHEAD PROTECTION AREA - the surface and subsurface area surrounding a water supply well, well field, spring or infiltration gallery supplying a public water system, through which contaminants are reasonably likely to move toward and reach the water source.
WETLAND - those areas that are 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 areas.