[Amended 1-4-2016 by Ord. No. 345; 9-20-2016 by Ord. No. 350; 6-17-2025 by Ord. No. 426]
For the purposes of this Part 1, certain terms and words used herein shall be interpreted as follows:
A.
Words used in the present tense include the future tense; the singular number includes the plural, and the plural number includes the singular; words of masculine gender include feminine gender; and words of feminine gender include masculine gender.
B.
The word "includes" or "including" shall not limit the term to the specific example but is intended to extend its meaning to all other instances of like kind and character.
C.
The words "shall" and "must" are mandatory; the words "may" and "should" are permissive.
D.
These definitions do not necessarily reflect the definitions contained in pertinent regulations or statutes, and are intended for this Part only.
E. ACCELERATED EROSION AGRICULTURAL ACTIVITY ALTERATION APPLICANT AS-BUILT DRAWINGS BANKFULL BASEFLOW BIORETENTION BMP (BEST MANAGEMENT PRACTICE) BMP MANUAL BUFFER CHANNEL CHANNEL EROSION CISTERN CONSERVATION DISTRICT CONVEYANCE COUNTY CULVERT DAM DEP (or PADEP) DESIGN STORM DETENTION BASIN DETENTION VOLUME DEVELOPER DEVELOPMENT DEVELOPMENT SITE DIAMETER AT BREAST HEIGHT (DBH) DIFFUSED DRAINAGE DISCHARGE DIRECTLY CONNECTED IMPERVIOUS AREA (DCIA) DISCONNECTED IMPERVIOUS AREA (DIA) DISTURBED AREA DITCH DOWNSLOPE PROPERTY LINE DRAINAGE CONVEYANCE FACILITY DRAINAGE EASEMENT DRAINAGE PLAN EARTH DISTURBANCE ACTIVITY EMERGENCY SPILLWAY ENCROACHMENT EROSION EROSION AND SEDIMENT CONTROL PLAN EXCEPTIONAL VALUE WATERS EXISTING CONDITION FEMA FLOOD FLOODPLAIN FLOODWAY FLUVIAL GEOMORPHOLOGY FOREST MANAGEMENT/TIMBER OPERATIONS FREEBOARD GRADE GRASSED WATERWAY GREEN INFRASTRUCTURE GROUNDWATER RECHARGE IMPERVIOUS SURFACE (IMPERVIOUS AREA) IMPOUNDMENT IMPROVED RESIDENTIAL LOT/PARCEL INFILL INFILTRATION INFILTRATION BASIN INFILTRATION STRUCTURE INFLOW INLET INTERMITTENT STREAM INVERT KARST LAND DEVELOPMENT(1) (a) (b) (2) (3) LIMITING ZONE(1) (2) (3) LOT LOW IMPACT DEVELOPMENT (LID) MAIN STEM (MAIN CHANNEL) MANNING EQUATION (MANNING FORMULA) MAXIMUM DESIGN STORM MUNICIPAL ENGINEER MUNICIPALITY NATURAL CONDITION NATURAL RECHARGE AREA NONPOINT SOURCE POLLUTION NONSTORMWATER DISCHARGES NONSTRUCTURAL BEST MANAGEMENT PRACTICE (BMPs) NPDES NRCS OPEN CHANNEL OUTFALL OUTFLOW OUTLET PADEP PEAK DISCHARGE PENNDOT (or PADOT) PERSON PERVIOUS AREA PIPE POINT SOURCE POST-CONSTRUCTION PRE-CONSTRUCTION PRE-DEVELOPMENT CONDITION PRETREATMENT PROJECT SITE QUALIFIED PERSON RAIN BARREL RAIN GARDEN RATIONAL FORMULA REACH RECHARGE RECHARGE VOLUME (REV) RECONSTRUCTION RECORD DRAWINGS REDEVELOPMENT REGULATED ACTIVITIES REGULATED EARTH DISTURBANCE ACTIVITY (Regulated Activity) RELEASE RATE RETENTION VOLUME/REMOVED RUNOFF RETURN PERIOD RIPARIAN BUFFER RIPARIAN FOREST BUFFER RISER ROAD MAINTENANCE ROOF DRAINS ROOFTOP DETENTION RUNOFF SALDO SCS SEDIMENT SEDIMENT BASIN SEDIMENT POLLUTION SEDIMENTATION SEEPAGE PIT/SEEPAGE TRENCH SEPARATE STORM SEWER SYSTEM SHALLOW CONCENTRATED FLOW SHEET FLOW SOIL-COVER COMPLEX METHOD SOURCE WATER PROTECTION AREAS (SWPA) SPILLWAY STANDARD GRADING PERMIT STATE WATER QUALITY REQUIREMENTS STORM SEWER STORMWATER STORMWATER MANAGEMENT FACILITY (SMF) STORMWATER MANAGEMENT PLAN STORMWATER MANAGEMENT SITE PLAN (or SWM Site Plan or Drainage Plan) STREAM STREAM BUFFER STREAM ENCLOSURE SUBAREA (SUBWATERSHED) SUBDIVISION SURFACE WATERS SWALE TIME-OF-CONCENTRATION (TC) TOP-OF-BANK TOWNSHIP USDA VERNAL POND WATER VOLUME CONTROL (see § 125-69) WATERCOURSE WATERS OF THE COMMONWEATH WATERSHED WATER VOLUME CONTROL WELLHEAD WELLHEAD PROTECTION AREA WET BASIN WETLAND
As used in this Part 1, the following terms shall have the meanings indicated:
The removal of the surface of the land through the combined action of human activities and the natural processes, at a rate greater than would occur because of the natural process alone.
Activities associated with agriculture such as agricultural cultivation, agricultural operation, and animal heavy use areas. This includes the work of producing crops, including tillage, land clearing, plowing, disking, harrowing, planting, harvesting crops or pasturing and raising of livestock and installation of conservation measures. Construction of new buildings or impervious area is not considered an agricultural activity.
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.
A landowner, developer or other person who has filed an application to the municipality for approval to engage in any regulated activity at a project site in the municipality.
Engineering or site drawings maintained by a developer to show the actual locations of building components and changes from the original contract documents. These documents, or a copy of same, are turned over to the municipality at the completion of the project.
The channel at the top-of-bank or point from where water begins to overflow onto a floodplain.
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 activities.
A stormwater retention area that utilizes woody and herbaceous plants and soils to remove pollutants before infiltration occurs.
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 Part 1. Stormwater BMPs are commonly grouped into one of two broad categories or measures: "structural" or "nonstructural." In this Part 1, nonstructural BMPs or measures refer to operational and/or behavior-related practices that attempt to minimize the contact of pollutants with stormwater runoff, or to provide other environmental or aesthetic benefits such as low-impact designs, riparian or forested buffers; whereas structural BMPs or measures are those that consist of a physical device or practice that is installed to capture and treat stormwater runoff. Structural BMPs include, but are not limited to, a wide variety of practices and devices, from large-scale retention ponds and constructed wetlands, to small-scale underground treatment systems, infiltration facilities, filter strips, bioretention, wet ponds, permeable paving, grassed swales, sand filters, detention basins, and manufactured devices. Structural stormwater BMPs are permanent appurtenances to the project site.
Pennsylvania Stormwater Best Management Practices Manual, No. 363-0300-002, as amended from time to time.
The area of land immediately adjacent to any stream, measured perpendicular to and horizontally from the top-of-bank on both sides of a stream (see "top-of-bank").
An open drainage feature through which stormwater flows. Channels include, but shall not be limited to, natural and man-made drainageways, swales, streams, ditches, canals, and pipes flowing partly full.
The widening, deepening, or headward cutting of channels and waterways caused by stormwater runoff or bankfull flows.
An underground reservoir or tank for storing rainwater.
A conservation district, as defined in Section 3(c) of the Conservation District Law [3 P.S. § 851(c)], that has the authority under a delegation agreement executed with DEP to administer and enforce all or a portion of the regulations promulgated under 25 Pa. Code Chapter 102.
A facility or structure used for the transportation or transmission of something from one place to another.
Montgomery County.
A structure with its appurtenant works which carries water under or through an embankment or fill.
Any artificial barrier, together with its appurtenant works, constructed for the purpose of impounding or storing water or any other fluid or semifluid or any refuse bank, fill or structure for highway, railroad or any other purpose which does or may impound water, fluid or semifluid.
The Pennsylvania Department of Environmental Protection.
The magnitude and temporal distribution of precipitation from a storm event measured in probability of occurrence that such magnitude will be equaled or exceeded in any one year (e.g., the twenty-percent chance, or so-called five-year (recurrence interval) storm), and duration (e.g., 24 hours), used in the design and evaluation of stormwater management systems. Also see "return period."
An impoundment designed to collect and retard stormwater runoff by temporarily storing the runoff and releasing it at a predetermined rate. Detention basins are designed to drain completely soon after a rainfall event, and to become dry until the next rainfall event.
The volume of runoff that is captured and released into waters of the commonwealth at a controlled rate.
A person that seeks to undertake any regulated earth disturbance activities at a project site in Whitpain Township.
Any human-induced change to improved or unimproved real estate, whether public or private, including, but not limited to, land development, construction, installation, or expansion of a building or other structure, land division, street construction, and site alteration such as embankments, dredging, grubbing, grading, paving, parking or storage facilities, excavation, filling, stockpiling, or clearing.
The specific area of land where any earth disturbance activities in the municipality are planned, conducted or maintained.
The outside bark diameter at breast height which is defined as 4.5 feet (1.37m) above the forest floor on the uphill side of the tree.
Drainage discharge that is not confined to a single point location or channel, including sheet flow or shallow concentrated flow.
An impervious or impermeable surface that is directly connected to a stormwater drainage or conveyance system, leading to direct runoff, decreased infiltration, decreased filtration, and decreased time of concentration.
An impervious or impermeable surface that is disconnected from any stormwater drainage or conveyance system, and is redirected or directed to a pervious area, which allows for infiltration, filtration, and increased time of concentration.
An unstabilized land area where an earth disturbance activity is occurring or has occurred.
A man-made waterway constructed for irrigation or stormwater conveyance purposes.
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 project site would be directed towards it by gravity.
A stormwater management facility designed to transport stormwater runoff that includes channels, swales, pipes, conduits, culverts, and storm sewers.
A right granted by a landowner to a grantee, allowing the use of private land for stormwater management purposes.
See "stormwater management site plan (or SWM site plant or drainage plan)."
A construction or other human activity which disturbs the surface of the 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.
A conveyance area that is used to pass peak discharge greater than the maximum design storm controlled by the stormwater facility.
A structure or activity that changes, expands, or diminishes the course, current, or cross-section of a watercourse, floodway, or body of water.
The natural process by which the surface of the land, including channels, is worn away by water, wind, or chemical action.
A plan for a project site which identifies BMPs to minimize accelerated erosion and sedimentation.
Surface waters having quality that satisfy one or more of the conditions established in Pennsylvania Code Title 25, Environmental Protection, Chapter 93, Water Quality Standards, § 93.4b(b).
The dominant land cover during the five-year period immediately preceding a proposed regulated activity.
Federal Emergency Management Agency.
A temporary condition of partial or complete inundation of land areas from the overflow of streams, rivers, and other waters of the commonwealth.
Any land area susceptible to inundation by water from any natural source or delineated by applicable FEMA maps and studies as being a special flood hazard area. Also includes areas that comprise Group 13 Soils, as listed in Appendix A of the Pennsylvania DEP Technical Manual for Sewage Enforcement Officers (as amended or replaced from time to time by DEP).
The channel of the watercourse and those portions of the adjoining floodplains that are reasonably required to carry and discharge the 100-year 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 floodway, it is assumed, absent evidence to the contrary, that the floodway extends from the stream to 50 feet from the top of the bank of the stream.
The study of landforms associated with river channels and the processes that form them.
Planning and activities necessary for the management of forestland. These include conducting a timber inventory, preparation of forest management plans, silvicultural treatment, cutting budgets, logging road design and construction, timber harvesting, site preparation, and reforestation.
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.
Either of the following:
A natural or man-made waterway, usually broad and shallow, covered with erosion-resistant grasses used to convey surface water.
Systems and practices that use or mimic natural processes to infiltrate, evapotranspire, or reuse stormwater on the site where it is generated.
The replenishment of existing natural underground water supplies from precipitation or overland flow.
A surface that prevents the infiltration of water into the ground. Impervious surfaces (or areas) shall include, but not be limited to, roofs, additional indoor living spaces, patios, garages, storage sheds and similar structures, swimming pools, and any new streets or sidewalks.
A retention or detention basin designed to retain stormwater runoff and release it at a controlled rate.
A parcel with existing impervious surface area located in a residential zoning district.
Development that occurs on smaller parcels that has remained undeveloped, but is within or in very close proximity to urban or densely developed areas. Infill development usually relies on existing infrastructure and does not require an extension of water, sewer, or other public utilities.
Movement of surface water into the soil, where it is absorbed by plant roots, evaporated into the atmosphere, or percolated downward to recharge groundwater.
A shallow impoundment that is designed to infiltrate stormwater into the soil. Infiltration basins are believed to have a high pollutant removal efficiency and can also help recharge the groundwater, thus restoring baseflows to stream systems. Infiltration basins can be problematic at many sites because of stringent soil requirements.
A structure designed to direct runoff into the ground (e.g., French drains, seepage pits or seepage trenches).
The flow entering the stormwater management facility and/or BMP.
The upstream end of any structure through which water may flow.
A stream that flows only part of the time. Flow generally occurs for several weeks or months in response to seasonal precipitation or groundwater discharge.
The lowest surface; the floor or bottom of a culvert, drain, sewer, channel, basin, BMP, or orifice.
A type of topography or landscape characterized by surface depressions, sinkholes, rock pinnacles/uneven bedrock surface, underground drainage, and caves. Karst is formed on carbonate rocks, such as limestone or dolomite.
Any of the following activities:
The improvement of one lot or two or more contiguous lots, tracts, or parcels of land for any purpose involving:
A group of two or more residential or nonresidential buildings, whether proposed initially or cumulatively, or a single nonresidential building on a lot or lots regardless of the number of occupants or tenure; or
The division or allocation of land or space, whether initially or cumulatively, 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;
A subdivision of land;
Development in accordance with Section 503(1.1) of the Pennsylvania Municipalities Planning Code.
A soil horizon or condition in the soil profile or underlying a stratum that includes one of the following:
A seasonal high water table, whether perched or regional, determined by direct observation of the water table or indicated by soil mottling.
A rock with open joints, fracture or solution channels, or masses of loose rock fragments, including gravel, with sufficient fine soil to fill the voids between the fragments.
A rock formation, other stratum, or soil condition that is so slowly permeable that it effectively limits downward passage of water.
A designated parcel, tract, or area of land established by a plat or otherwise as permitted by law and to be used, developed, or built upon as a unit.
Site design approaches and small-scale stormwater management practices that promote the use of natural systems for infiltration, evapotranspiration, and reuse of rainwater. LID can be applied to new development, urban retrofits, and revitalization projects. LID utilizes design techniques that infiltrate, filter, evaporate, and store runoff close to its source. Rather than rely on costly large-scale conveyance and treatment systems, LID addresses stormwater through a variety of small, cost-effective landscape features located on-site.
Any stream segment or other runoff conveyance used as a reach in the Watershed hydrologic model.
A method for calculation of velocity of flow (e.g., feet per second) and flow or discharge 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.
The maximum (largest) design storm that is controlled by the stormwater facility.
A professional engineer (PE) licensed as such in the Commonwealth of Pennsylvania, duly appointed as the Engineer for a municipality, planning agency, or joint planning commission.
Whitpain Township, Montgomery County, Pennsylvania.
Pre-development condition.
Undisturbed surface area or depression where stormwater collects and a portion of which infiltrates and replenishes the underground and groundwater.
Pollution that enters a waterbody from diffuse origins in the watershed and does not result from discernible, confined, or discrete conveyances.
Water flowing in stormwater collection facilities, such as pipes or swales, which are not the result of a rainfall event or snowmelt.
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.
National Pollutant Discharge Elimination System, the federal government's system for issuance of permits under the Clean Water Act,[1] which is delegated to DEP in Pennsylvania.
Natural Resource Conservation Service of the U.S. Department of Agriculture [previously the Soil Conservation Service (SCS)].
A conveyance channel that is not enclosed.
"Point source" as described in 40 CFR 122.2 at the point where Whitpain Township's storm sewer system discharges to surface waters of the commonwealth.
The flow exiting the stormwater management facility and/or BMP.
Points of water disposal to a stream, river, lake, tidewater, or artificial drain.
The Pennsylvania Department of Environmental Protection.
The maximum rate of flow of storm runoff at a given point and time resulting from a specified storm event.
Pennsylvania Department of Transportation.
An individual, partnership, public or private association or corporation, or a governmental unit, public utility or any other legal entity whatsoever which is recognized by law as the subject of rights and duties.
Any area not defined as impervious.
A culvert, closed conduit, or similar structure (including appurtances) that conveys stormwater.
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 regulations at 25 Pa. Code § 92.1.
Period after construction during which disturbed areas are stabilized, stormwater controls are in place and functioning, and all proposed improvements in the approved land development plan are completed.
Prior to commencing construction activities.
Undeveloped/natural condition.
Techniques employed in stormwater BMPs to provide storage or filtering to trap coarse materials and other pollutants before they enter the system, but not necessarily designed to meet the water quality volume control requirements (WQV) of § 125-69. For example, any inlets draining to an infiltrating system should be sumped and trapped to prevent the system from becoming clogged with excess sediment.
The specific area of land where any regulated earth disturbance activities in the municipality are planned, conducted or maintained.
Any person licensed by the Pennsylvania Department of State or otherwise qualified by law to perform the work required by this Part.
An above-ground reservoir or tank for the collection of stormwater from roof leaders, from which a person may recycle such rainwater for various uses, including, but not limited to, watering vegetation and washing vehicles.
A BMP that is a planted depression or shallow hole that collects stormwater runoff from impervious areas, such as roofs, driveways, hardscaping and paved parking lots. Rain gardens are designed, constructed and maintained for the purpose of providing infiltration or recharge of stormwater into the soil and/or underground aquifer. A rain garden shall have a maximum ponding depth of one foot and shall be in conformance with the Pennsylvania DEP BMP guidelines, as amended from time to time.
A rainfall-runoff equation used to estimate peak flow; Q = CiA.
Any stream segment or other runoff conveyance used in the Watershed hydrologic model.
The replenishment of groundwater through the infiltration of rainfall, other surface waters, or land application of water or treated wastewater.
The volume of stormwater, in cubic feet, required to be infiltrated on site, where practicable and appropriate.
Demolition and subsequent rebuilding of impervious surface.
Construction drawings revised to represent the as-built conditions.
Any development that requires demolition or removal of existing structures or impervious surfaces at a site and replacement with new impervious surfaces. Maintenance activities such as top-layer grinding and repaving are not considered to be redevelopment. Interior remodeling projects and tenant improvements are also not considered to be redevelopment.
Any earth disturbance activities or any activities that involve the alteration or development of land in a manner that may affect stormwater runoff.
Activity involving earth disturbance subject to regulation under 25 Pa. Code Chapter 92, 25 Pa. Code Chapter 102, or the Clean Streams Law.[2]
The level of control of the postdevelopment peak rate of runoff to be achieved for a particular site, expressed as a percentage of the predevelopment peak rate of runoff.
The volume of runoff that is captured and not released directly into the surface waters of this commonwealth during or after a storm event.
The average interval, in years, within which a storm event of a given or greater magnitude can be expected to recur. For example, the twenty-five-year return period rainfall would be expected to recur on the average of once every 25 years, or conversely would have a four-percent chance of occurrence or exceedance in any given year.
An area of land adjacent to a body of water and managed to maintain the integrity of stream channels and shorelines to 1) reduce the impact of upland sources of pollution by trapping, filtering, and converting sediments, nutrients, and other chemicals, and 2) supply food, cover and thermal protection to fish and other wildlife.
A type of riparian buffer that consists of permanent vegetation that is predominantly native trees, shrubs, and forbs along surface waters that is maintained in a natural state or sustainably managed to protect and enhance water quality, stabilize stream channels and banks, and separate land use activities from surface waters.
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.
Earth disturbance activities within the existing road cross section, such as grading and repairing existing unpaved road surfaces, cutting road banks, cleaning or clearing drainage ditches and other similar activities.
A drainage conduit or pipe that collects water runoff from a roof and leads it away from the structure.
The temporary ponding and gradual release of stormwater falling directly onto flat roof surfaces using controlled-flow roof drains in building designs.
That part of precipitation which flows over the land.
Subdivision and Land Development Ordinance.
The Soil Conservation Service, United States Department of Agriculture.
Soils or other materials transported by surface water as a product of erosion.
A barrier, dam, or retention or detention basin located and designed in such a way as to retain rock, gravel, sand, silt, clay or other material transported by water during construction.
The placement, discharge, or any other introduction of sediment into the waters of the commonwealth.
The process by which mineral or organic matter is accumulated or deposited by the movement of water or air.
An area of excavated earth filled with loose stone or similar material and into which surface water is directed for infiltration into the ground.
A conveyance or system of conveyances (including roads with drainage systems, municipal streets, catch basins, curbs, gutters, ditches, man-made channels or storm drains) primarily used for collecting and conveying stormwater runoff.
Stormwater runoff flowing in shallow, defined ruts prior to entering a defined channel or waterway.
A flow process associated with broad, shallow water movement on sloping ground surfaces that is not channelized or concentrated.
A method of runoff computation developed by the National Resources Conservation Service (NRCS) that is based on relating soil type and land use/cover to a runoff parameter curve number (CN).
The zones through which contaminants, if present, are likely to migrate and reach drinking water wells or surface water intakes.
A conveyance that is used to pass the peak discharge of the maximum design storm that is controlled by the stormwater facility.
The permit required to be issued by the municipality before any grading activities are allowed to commence on a site within the municipality. Such permits typically require information, including, but not limited to, a contour map of the site showing existing and proposed contours, a plot plan showing streams and drainage courses on or within 50 feet of the site, drainage structures, neighboring streets and alleys, trees, and floodplain zones on or within 50 feet of the site, and soil classifications.
The regulatory requirements to protect, maintain, reclaim, and restore water quality under Title 25 of the Pennsylvania Code and the Clean Streams Law.[3]
A system of pipes and/or open channels that convey intercepted runoff and stormwater from other sources but exclude domestic sewage and industrial wastes.
Drainage runoff from the surface of the land resulting from precipitation or snow or ice melt.
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; and infiltration facilities.
The watershed plan, for managing those land use activities that will influence stormwater runoff quality and quantity.
A plan prepared by the applicant or the applicant's representative indicating how stormwater runoff will be managed at the project site to meet the requirements of this Part 1 for managing stormwater runoff adopted by Whitpain Township.
A natural watercourse.
The land area adjacent to each side of a stream essential to maintaining water quality (see "buffer").
A bridge, culvert, or other structure in excess of 100 feet in length upstream to downstream, which encloses a regulated water of the commonwealth.
The smallest unit of watershed breakdown for hydrologic modeling purposes for which the runoff control criteria have been established in the stormwater management plan.
The division or redivision 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, of lease, partition by the court for distribution to heirs or devisees, transfer of ownership, or building or lot development; provided, however, that the subdivision by lease of land for agricultural purposes into parcels of more than 10 acres not involving any new street or easement of access or any residential dwelling shall be exempted. As defined in the Pennsylvania Municipalities Planning Code, Act of July 31, 1968, P.L. 805, No. 247.[4]
Perennial and intermittent streams, rivers, lakes, reservoirs, ponds, wetlands, springs, natural seeps, and estuaries, excluding water at facilities approved for wastewater treatment, such as wastewater treatment impoundments, cooling water ponds, and constructed wetlands used as part of a wastewater treatment process.
A low-lying stretch of land which gathers or carries surface water runoff.
The time required for surface runoff to travel from the most remote point of a watershed to the watershed outlet.
Highest point of elevation in a stream channel cross-section at which a rising water level just begins to flow outside of the channel and over the floodplain.
Whitpain Township, with offices located at 960 Wentz Road, Blue Bell, Pennsylvania.
United States Department of Agriculture.
Seasonal depressional wetlands that are covered by shallow water for variable periods from winter to spring but may be completely dry for most of the summer and fall.
The storage capacity, in acre-feet, required to capture and treat a portion of stormwater runoff from the developed or redeveloped areas of the site.
A channel or conveyance of surface water, such as a stream or creek, having defined bed and banks, whether natural or artificial, with perennial or intermittent flow.
Any and all rivers, streams, creeks, rivulets, impoundments, 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.
Region or area drained by a river, watercourse or other body of water, whether natural or artificial.
(See § 125-69.) The storage capacity, in acre-feet, required to capture and treat a portion of stormwater runoff from the developed or redeveloped areas of the site.
Either one of the following:
The surface and subsurface area surrounding a water supply well, well field, or spring supplying a public water system through which contaminants are reasonably likely to move toward and reach the water source.
Pond for urban runoff management that is designed to detain urban runoff and always contains water.
Areas that are inundated or saturated by surface or groundwater 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, and similar areas.