[Ord. 2011-6, 5/19/2011, Art. II]
1. 
For the purposes of this chapter, 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 word "person" includes an individual, firm, association, organization, partnership, trust, company, corporation or any other similar entity.
D. 
The words "shall" and "must" are mandatory; the words "may" and "should" are permissive.
E. 
The words "used" or "occupied" include the words "intended," "designed," "maintained," or "arranged to be used," "occupied" or "maintained."
F. 
Terms defined.
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.
AGRICULTURAL ACTIVITY
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 livestock, and installation of conservation measures. Construction of new buildings or impervious area is not considered agricultural activity.
ALLUVIAL SOILS (FLOODPLAIN SOILS)
Areas subject to periodic flooding and listed in the Soil Survey of Bucks and Philadelphia Counties, Pennsylvania, U.S., Department of Agricultural Soil Conservation Service as being "on, or in, the floodplain" or subject to flooding.
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; or earth disturbance.
APPLICANT
A landowner or developer who has filed an application for approval to engage in any regulated activities as defined in § 23-104 of this chapter.
AS-BUILT PLAN
Plans that are maintained during construction of the project and which document the actual locations of the site improvements. As-built plan must be prepared by a professional land surveyor, landscape architect or professional engineer licensed in the Commonwealth of Pennsylvania.
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 groundwater discharge.
BIORENTENTION
A stormwater retention area which utilizes woody and herbaceous plants and soils to remove pollutants before infiltration occurs.
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 protect and maintain water quality and groundwater recharge and to otherwise meet the purposes of this chapter. Stormwater BMPs are commonly grouped into one or two broad categories or measures: " structural" or " nonstructural." In this chapter, nonstructural BMPs or measures refer to operational and/ or behavior -related practices that attempt to minimize the contact of pollutants with stormwater runoff 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, low impact design, bioretention, wet ponds, permeable paving, grassed swales, riparian or forested buffers, sand filters, detention basins, and manufactured devices. Structural stormwater BMPs are permanent appurtenances to the project site.
[Amended by Ord. No. 2022-005, 9/6/2022]
BMP MANUAL
Pennsylvania Best Management Practices Manual, December 2006, as amended.
CHANNEL
An open drainage feature through which stormwater flows. Channels include but shall not be limited to, natural and man-made watercourses, swales, streams, ditches, canals and pipes that convey continuously or periodically flowing water.
CHANNEL EROSION
The widening, deepening and headward cutting of channels and waterways, due to erosion caused by moderate to large floods.
CISTERN
An underground reservoir or tank for storing rainwater.
COMMERCIAL CONTAINER NURSERY
A commercial nursery that grows 50% or more of its herbaceous plants, shrubs and trees in containers on their lot rather than in the ground.
CONSERVATION DISTRICT
Bucks County Conservation District. 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 102.
[Amended by Ord. No. 2022-005, 9/6/2022]
COUNTY
Bucks County.
CULVERT
A pipe, conduit or similar structure including appurtenant works which conveys surface water under or through an embankment or fill.
CURVE NUMBER (CN) VALUE USED IN THE SOIL COVER COMPLEX METHOD
It is a measure of the percentage of precipitation which is expected to run off from the watershed and is a function of the soil, vegetative cover and tillage method.
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 semifluid.
DEP (or PADEP)
The Pennsylvania Department of Environmental Protection.
DEPARTMENT
The Pennsylvania Department of Environmental Protection.[1]
DESIGN STORM
The magnitude and temporal distribution of precipitation from a storm event measured in probability of occurrence (e.g., fifty-year storm) and duration (e.g., 24 hours), used in the design and evaluation of stormwater management systems. Also see "return period."
[Amended by Ord. No. 2022-005, 9/6/2022]
DESIGNEE
The agent of the Board of Supervisors involved with the administration, review or enforcement of any provisions of this chapter by contract or memorandum of understanding.
DETENTION BASIN
An impoundment structure designed to manage 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.
DETENTION DISTRICT
Those subareas in which some type of detention is required to meet the plan requirements and goals of Act 167.
DETENTION VOLUME
The volume of runoff that is captured and released into the Waters of the Commonwealth at a controlled rate.
[Amended by Ord. No. 2022-005, 9/6/2022]
DEVELOPER
A person, partnership, association, corporation or other entity, or any responsible person therein or agent thereof, that undertakes any regulated activity of this chapter.
DEVELOPMENT
Any man-made change to improved or unimproved real estate including, but not limited to, the construction or placement of buildings or other structures, mobile homes, streets and other paving, utilities, mining, dredging, filling, grading, excavation or drilling operations, and the subdivision of land.
DEVELOPMENT PLAN
The provisions for development including a planned residential development, a plat of subdivision, all covenants relating to use, location and bulk of buildings and other structures, intensity of use or density of development, streets, ways and parking facilities, common open space and public facilities. The phrase "provisions of development plan" when used in this chapter shall mean the written and graphic materials referred to in this definition.
DEVELOPMENT SITE
See "project site."
[Amended by Ord. No. 2022-005, 9/6/2022]
DIFFUSED DRAINAGE DISCHARGE
Drainage discharge not confined to a single point location or channel, such as sheet flow or shallow concentrated flow.
DISCHARGE
(1) 
(verb) To release water from a project, site, aquifer, drainage basin or other point of interest;
(2) 
(noun) The rate and volume of flow of water such as in a stream, generally expressed in cubic feet per second (CFS).
DISCONNECTED IMPERVIOUS AREA (DIA)
An impervious 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.
DISTURBED AREAS
Unstabilized 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 where all overland or pipe flow from the proposed development is directed.
DOWNSTREAM HYDRAULIC CAPACITY ANALYSIS
Any downstream capacity hydraulic analysis conducted in accordance with this chapter shall use the following criteria for determining adequacy for accepting increased peak flow rates:
(1) 
Natural or man-made channels or swales must be able to convey the increased rate of runoff associated with a two-year return period event within their banks at velocities consistent with protection of the channels from erosion. Acceptable velocities shall be based upon criteria included in the DEP Erosion and Sediment Pollution Control Program Manual.
(2) 
Natural or man-made channels or swales must be able to convey the increased twenty-five-year return period rate of runoff without creating any hazard to persons or property.
(3) 
Culverts, bridges, storm sewers or any other facilities which must pass or convey flows from the tributary area must be designed in accordance with DEP 25 Pa. Code, Chapter 105 regulations (if applicable) and, at a minimum, pass the increased twenty-five-year return period rate of runoff.
(4) 
No new channels or conveyance facilities shall be authorized by this language.
DRAINAGE CONVEYANCE FACILITY
A stormwater management facility designed to transmit stormwater runoff which shall include streams, channels, swales, pipes, conduits, culverts, storm sewers, etc.
DRAINAGE EASEMENT
A right granted by a landowner to a grantee, allowing the use of private land for stormwater management purposes.
DRAINAGE PERMIT
A permit issued by the Township after the SWM plan has been approved.
DRY POND (DRY EXTENDED DETENTION POND)
Dry extended detention ponds do not maintain a permanent pool between storm events. Outlets are designed to detain the volume of a water quality design storm for a minimum (usually 48 hours) to allow for the settling of particles and associated pollutants. In addition, dry extended detention ponds provide flood control by including additional temporary storage for peak flows above the dead storage. Extended detention ponds are also capable of managing smaller floods that contribute to channel erosion problems and occur more frequently than the annual or two-year flood.
EARTH DISTURBANCE (OR EARTH DISTURBANCE ACTIVITY)
A construction or other human activity which disturbs and destabilizes the surface of the land, including, but not limited to, clearing and grubbing, grading, excavations, embankments, land development, road maintenance; building construction; and the moving, depositing, stockpiling or storing of soil, rock or earth materials.
[Amended by Ord. No. 2022-005, 9/6/2022]
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.
ENGINEER
A licensed professional civil engineer registered by the Commonwealth of Pennsylvania.
EROSION
The process by which the surface of the land, including channels, is worn away by water, wind or chemical action.
EROSION AND SEDIMENT POLLUTION CONTROL PLAN
A site-specific plan identifying the BMPs to minimize accelerated erosion and sedimentation, pursuant to 25 Pa. Code, Chapter 102.
EXCEPTIONAL VALUE WATERS
Surface waters of high quality which satisfy 25 Pa. Code, Chapter 93, "Water Quality Standards," § 93.413(b) (relating to antidegradation).
EXISTING CONDITIONS
The dominant land cover during the five-year period immediately preceding a proposed regulated activity.
[Amended by Ord. No. 2022-005, 9/6/2022]
EXISTING RECHARGE AREA
Undisturbed surface area or depression where stormwater collects and a portion of which infiltrates and replenishes the groundwater.
EXISTING RESOURCES AND SITE ANALYSIS MAP
A base map which identifies fundamental environmental site information including floodplains, wetlands, topography, vegetative site features, natural areas, prime agricultural land and areas supportive of endangered species.
FEMA
Federal Emergency Management Agency.
[Added by Ord. No. 2022-005, 9/6/2022[2]]
FLOOD
A general but temporary condition of partial or complete inundation of normally dry 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 as a special flood hazard area on the applicable National Flood Insurance Program Flood Insurance Rate Map (FIRM) prepared by the Federal Emergency Management Agency (FEMA). Also included are areas that comprise Group 13 Soils, as listed in Appendix A of the Pennsylvania Department of Environmental Protection (PADEP) Technical Manual for Sewage Enforcement Officers (as amended or replaced from time to time by PADEP).
FLOODWAY
The channel of the watercourse and those portions of the adjoining floodplains that are reasonably required to carry and discharge the one-hundred-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 one-hundred-year frequency 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.
FOREST MANAGEMENT/TIMBER OPERATIONS
Planning and associated activities necessary for the management of forestland. These include conducting a timber inventory, preparation of forest management plans, silviculture treatment, cutting budgets, logging road design and construction, timber harvesting, site preparation and reforestation.
[Amended by Ord. No. 2022-005, 9/6/2022]
FREEBOARD
A vertical distance between the elevation of the design high-water and the top of a dam, levee, tank, basin or diversion ridge. The space is required as a safety margin in a pond or basin.
GEOLOGIST
A licensed professional geologist registered in the Commonwealth of Pennsylvania.
GRADE
(1) 
(noun) A slope usually of a street, other public way, land area, drainage facility or pipe specified in percent;
(2) 
(verb) To finish the surface of a road bed, 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 conduct surface water.
GREEN INFRASTRUCTURE
Systems and practices that use or mimic natural processes to infiltrate, evapotranspire, or reuse stormwater on the site where it is generated.
[Added by Ord. No. 2022-005, 9/6/2022]
GROUNDWATER
Water beneath the earth's surface that supplies wells and springs, and is often between saturated soil and rock.
GROUNDWATER RECHARGE
Replenishment of natural underground water supplies.
HEC-HMS
The U.S. Army Corps of Engineers, Hydrologic Engineering Center (HEC) Hydrologic Modeling System (HMS).
HIGH QUALITY WATERS
Surface waters having quality which exceeds levels necessary to support propagation of fish, shellfish and wildlife and recreation in and on the water by satisfying 25 Pa. Code, Chapter 93, "Water Quality Standards," § 93.4b(a).
HOT SPOT
An area where land use or activity generates highly contaminated runoff; with concentrations of pollutants in excess of those typically found in stormwater. Typical pollutant loadings in stormwater may be found in Chapter 8, § 6, of the Pennsylvania Stormwater Best Management Practices Manual, Pennsylvania Department of Environmental Protection (PADEP) No. 363-0300-002 (2006). More information concerning hot spots may be found in Appendix 23-G of this chapter.
HYDRIC SOIL
A soil that is saturated, flooded or ponded long enough during the growing season to develop an anaerobic condition in the upper part.
HYDROLOGIC REGIME (NATURAL)
The hydrologic cycle or balance that sustains quality and quantity of stormwater, baseflow, storage and groundwater supplies under the natural conditions.
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 to their minimum infiltration rate, which is obtained for bare soil after prolonged wetting. The Natural Resources Conservation Service (NRCS) of the US Department of Agriculture defines the four groups and provides a list of most of the soils in the United States and their group classification. The soils in the area of the development site may be identified from a 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 to D.
[Amended by Ord. No. 2022-005, 9/6/2022]
HYETOGRAPH
A graphical representation of average rainfall, rainfall excess rates or volumes over specified areas during successive units of time during a storm.
IMPERVIOUS SURFACE (OR IMPERVIOUS AREA)
Surfaces which prevent the infiltration of water into the ground. All buildings, parking areas, driveways, roads, sidewalks, swimming pools and any areas containing concrete, asphalt, packed stone, compacted soils or other equivalent surfaces shall be considered impervious within this definition. In addition, other areas determined by the Township Engineer to be impervious within the meaning of this definition shall be classified as impervious surfaces.
[Amended by Ord. No. 2022-005, 9/6/2022]
IMPOUNDMENT
A retention or detention basin designed to retain stormwater runoff and release it at a controlled rate.
INFILTRATION
Movement of surface water into the soil, where it is absorbed by plant roots, evaporated into the atmosphere or percolated downward to recharge groundwater.
INFILTRATION STRUCTURES
A structure designed to direct runoff into the ground (e.g., french drains, seepage pits, seepage trench, biofiltration swale, infiltration basins).
INLET
A surface connection to a closed drain. A structure at the diversion end of a conduit. The upstream end of any structure through which water may flow.
KARST
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.
LAND DEVELOPMENT
Any of the following activities:
(1) 
The improvement of one or two or more contiguous lots, tracts or parcels of land for any purpose involving:
(a) 
A group of two or more residential or nonresidential buildings, whether purposed initially or cumulatively, or a single nonresidential building on a lot or lots regardless of the number of occupants or tenure.
(b) 
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.
(2) 
A subdivision of land.
(3) 
"Land development" does not include development which involves:
(a) 
The conversion of an existing single-family detached dwelling or single-family semidetached dwelling into not more than three residential units, unless such units are intended to be a condominium.
(b) 
The addition of a residential accessory building, including farm building, on a lot or lots subordinate to an existing principal building.
(c) 
The addition or conversion of buildings or rides within the confines of an enterprise which would be considered an amusement park. For the purposes of this subsection, an amusement park is defined as a tract or area used principally as a location for permanent amusement structures or rides. This exclusion shall not apply to newly acquired acreage by an amusement park until initial plans for the expanded area have been approved by the proper authorities.
LAND/EARTH DISTURBANCE
Any activity involving grading, tilling, digging or filling of ground or stripping of vegetation or any other activity that causes an alteration to and destabilization of the natural condition of the land.
LANDSCAPE ARCHITECT
A person who engages or offers to engage in the practice of landscape architecture in the Commonwealth of Pennsylvania under the authority of the Landscape Architects Registration Law, 63 P.S. § 901 et seq.
LIMIT OF EARTH DISTURBANCE
The perimeter of earth disturbance on a site.
LIMITING ZONE
A soil horizon or condition in the soil profile or underlying strata which includes one of the following:
(1) 
A seasonal high water table, whether perched or regional, determined by direct observation of the water table or indicated by soil mottling.
(2) 
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.
(3) 
A rock formation, other stratum or soil condition which is so slowly permeable that is effectively limits downward passage of effluent.
LOW-IMPACT DEVELOPMENT (LID)
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.
[Amended by Ord. No. 2022-005, 9/6/2022]
MAIN STEM (MAIN CHANNEL)
Any stream segment or other runoff conveyance facility used as a reach in the watershed 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 when the flow is not under pressure.
MUNICIPALITY
Solebury Township, Bucks County, Pennsylvania.
NONPOINT SOURCE POLLUTION
Pollution that enters a watery body from diffuse origins in the watershed and does not result from discernible, confined or discrete conveyances.
NONSTORMWATER DISCHARGES
Water flowing in stormwater collection facilities, such as pipes or swales, which is not the result of a rainfall event or snowmelt.
NPDES
National Pollution Discharge Elimination System, the federal governments system of regulations for the issuance of permits under the Clean Water Act, 33 U.S.C.A. § 1251 et seq., which is delegated to PADEP in Pennsylvania.
NRCS
USDA Natural Resource Conservation Service (previously SCS).
[Amended by Ord. No. 2022-005, 9/6/2022]
OPEN 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 drainageways, swales, streams, ditches, canals and pipes flowing partly full.
OUTFALL
"The point source" as described in 40 CFR 122.2 where the municipality's storm sewer system discharges to surface waters of the commonwealth.
OUTLET
Points of water disposal to a stream, river, lake, tidewater or artificial basin.
PARENT TRACT
The parcel of land from which a land development or subdivision originates as of the date of adoption of this chapter.
PEAK DISCHARGE
The maximum rate of stormwater runoff from a specific storm event.
PENN STATE RUNOFF MODEL (CALIBRATED)
The computer-based hydrologic modeling technique adapted to the watershed for the Act 167 Plan. The model has been "calibrated" to reflect actual recorded flow values by adjoining key model input parameters.
PERMANENTLY PRESERVED LAND
A parcel or tract of and that is subject to a recorded conservation easement, in perpetuity, in a manner acceptable to the Township.
PERSON
An individual, partnership, association, corporation or other entity.
PERVIOUS AREA (or PERVIOUS SURFACE)
A surface that allows the infiltration of water into the ground.
[Amended by Ord. No. 2022-005, 9/6/2022]
PIPE
A culvert, closed conduit or similar structure (including appurtenances) that conveys stormwater.
PLANNING COMMISSION
The Planning Commission of the Township.
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 on the basis of data obtained from the National Oceanographic and Atmospheric Administration (NOAH).
POINT SOURCE
Any discernible, confined and discrete conveyance, including, but not limited to, any pipe, ditch, channel, tunnel or conduit from which stormwater as defined in state regulations at 25 Pa. Code § 92.1, is or may be discharged.
POST CONSTRUCTION
Period after construction during which disturbed areas are stabilized, stormwater controls are in place and functioning, and all improvements in the approved SWM plan are completed.
PRETREATMENT
Techniques employed in stormwater BMPs to provide storage or filtering to trap coarse materials and other pollutants before they enter the stormwater management or infiltration system.
PROJECT SITE
The specific tract of land where any regulated activity in the Township is planned, conducted, or maintained.
[Amended by Ord. No. 2022-005, 9/6/2022]
QUALIFIED PROFESSIONAL
Any person licensed by the Pennsylvania Department of State or otherwise qualified by law and trained to perform work required by this chapter. Qualified professionals include professional engineers, registered landscape architects, and professional land surveyors.
[Added by Ord. No. 2022-005, 9/6/2022]
RATIONAL METHOD
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.
RECHARGE VOLUME
A calculated volume of stormwater runoff from impervious areas which is required to be infiltrated at a site and may be achieved through use of structural or nonstructural BMPs.
REGULATED ACTIVITIES
Any activity to which this chapter is applicable pursuant to § 23-104 of this chapter.
REGULATED EARTH DISTURBANCE ACTIVITY
Activity involving earth disturbance subject to regulation under 25 Pa. Code, Chapter 92a, 25 Pa. Code, Chapter 102, or the Clean Streams Law, 35 P.S. § 691.1 et seq.
RELEASE RATE
The percentage of predevelopment peak rate of runoff from a site or subarea to which the post development peak rate of runoff must be reduced to protect downstream areas.
RETENTION BASIN
A basin designed to retain stormwater runoff so that a permanent pool is established.
RETENTION VOLUME/REMOVED RUNOFF
The volume of runoff that is captured and not released directly into the surface waters of the Commonwealth during or after a storm event.
[Amended by Ord. No. 2022-005, 9/6/2022]
RETURN PERIOD
The average interval, in years, within which a storm event of a given magnitude can be expected to recur. For example, the twenty-five-year return period rainfall would be expected to recur on the average once every 25 years.
RIPARIAN BUFFER
A permanent area of trees and shrubs located adjacent to streams, lakes, ponds and wetlands.
[Added by Ord. No. 2022-005, 9/6/2022]
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.
ROAD MAINTENANCE
Earth disturbance activities within an 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.
RUNOFF
Any part of precipitation that flows over the land surface.
SEDIMENT
Soils or other materials transported by surface water as a product of erosion.
[Added by Ord. No. 2022-005, 9/6/2022]
SEDIMENT BASIN
A barrier, dam or retention or detention basin located and designed to retain rock, sand, gravel, silt or other material transported by water.
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.
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 (refer PA BMP Manual, December 2006, Chapter 6, § 4).
SEPARATE STORM SEWER SYSTEM
A system of pipes, open channels, streets and other conveyances intended to carry stormwater runoff.
SHALLOW CONCENTRATED FLOW
Stormwater runoff flowing in shallow, defined ruts prior to entering a defined channel or waterway.
SHEET FLOW
Runoff that flows over the ground surface as a thin, even layer, not concentrated in a channel.
SOIL GROUP, HYDROLOGIC
A classification of soils by the NRCS into four 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.
SOIL SCIENTIST
An individual trained to observe and identify soil properties that can be used to determine such things as depth to seasonal high water table, soil permeability, potential productivity and other potentially use-limiting soil features.
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 a 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 that have been designated in 25 Pa. Code, Chapter 93, "Water Quality Standards," as exceptional value (EV) or high quality (HQ) waters.
STATE WATER QUALITY REQUIREMENTS
The regulatory requirements to protect, maintain, reclaim, and restore water quality under Title 25 ofthe Pennsylvania Code and the Clean Streams Law.[3]
[Added by Ord. No. 2022-005, 9/6/2022]
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. Refer "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
Drainage runoff from the surface of the land resulting from precipitation or snow or ice melt.
[Amended by Ord. No. 2022-005, 9/6/2022]
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, infiltration structures and other BMPs.
STORMWATER MANAGEMENT PERMIT
A permit issued by the Township Board of Supervisors after the drainage plan has been approved. Said permit is issued prior to or with the final Township approval.
STORMWATER MANAGEMENT PLAN
The plan for managing stormwater runoff within the Township adopted as required by the Act of October 4, 1978, P.L. 864, (Act 167), 32 P.S. § 680.1 et seq.
STORMWATER MANAGEMENT SITE PLAN
The plan prepared by the developer or his representative indicating how stormwater runoff will be managed at the development site in accordance with this chapter. Stormwater management site plan may also be designated as SWM site plan throughout this chapter.
[Amended by Ord. No. 2022-005, 9/6/2022]
STREAM
Rivers, creeks, springs and other watercourses containing water at least on a seasonal basis during an average water year. The term "stream" shall include the following:
SPRINGS OR SEEPS — The point where groundwater discharges to become surface water.
STREAM, EPHEMERAL — A reach of stream that flows only during and for short periods following precipitation and flows in low areas that may or may not be a well-defined channel. Ephemeral stream beds are located above the water table year-round. Groundwater is not a source of water for the stream. Some commonly used names for ephemeral streams include: stormwater channel, drain, swale, gully, dry stream channel, hollow or saddle. The term often used interchangeably with intermittent stream but the difference is in the length of time of continuous flow (less than one month per year).
STREAM, HEADWATER — The beginning reach of a stream that collects water from springs and seeps and provides a hydrologic connection to a perennial stream. These channels may be ill defined and may move from year to year depending upon groundwater input, snowmelt and runoff, but are typified by hydric soils and hydric vegetation.
STREAM, INTERMITTENT — A reach of stream that flows only during wet periods of the year (30% to 90% of the time) and flows in a continuous well-defined channel. During dry periods, especially in summer months, intermittent streams may go down to a trickle of water and make it appear dry, when in fact there is water flowing through the stream bottom or "substrate." This is usually caused by the seasonal changes of the local soil water table or during periods of long-term drought.
STREAM, PERENNIAL — A body of water in a channel that flows throughout a majority of the year in a defined channel and is capable, in the absence of pollution, drought or man-made stream disturbances, of supporting a benthic macroinvertebrate community that is composed of two or more recognizable taxonomic groups of organisms, large enough to be seen by the unaided eye and can be retained by a U.S. Standard No. 30 sieve (28 meshs per inch, 0.595 mm openings) and live at least part of their life cycles within or upon available substrates in a body of water or water transport system. A perennial stream can have Q7-10 flow of zero. For the purposes of this document, a perennial stream includes lakes and ponds.
STREAM BUFFER
The land area adjacent to each side of a stream, essential to maintaining water quality, measured perpendicular to and horizontally from the top-of-bank.
STREAM ENCLOSURE
A bridge, culvert or other structure in excess of 100 feet in length upstream to downstream which encloses a regulated water of this commonwealth.
STREAMBANK EROSION
The widening, deeping or headward cutting of channels and waterways caused by stormwater runoff or bankfull flows.
SUBAREA (SUBWATERSHED)
The smallest drainage unit of a watershed for which stormwater management criteria have been established in the stormwater management plan.
SUBDIVISION
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, 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 dwellings, shall be exempt.
[Amended by Ord. No. 2022-005, 9/6/2022]
SURVEYOR
An individual licensed and registered under the laws of the Commonwealth of Pennsylvania to engage in the practice of land surveying.
SWALE
A low-lying stretch of land which gathers or carries surface water runoff.
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.
TOP OF BANK
Highest point of elevation in a stream channel cross section at which a rising water level just begins to flow out of the channel and over the floodplain.
TOWNSHIP
Solebury Township, Bucks County, Pennsylvania.
TOWNSHIP ENGINEER
A professional engineer licensed as such in the Commonwealth of Pennsylvania and appointed by the Township pursuant to Article XII of the Second Class Township Code, 53 P.S. § 66201 et seq.
TRIBUTARY AREA
The portion of a watershed that contributes runoff to a particular point in that watershed.
USDA
United States Department of Agriculture.
[Added by Ord. No. 2022-005, 9/6/2022]
VERNAL POOL
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.
VOLUMETRIC RUNOFF COEFFICIENT
A variable indicative of stormwater runoff volume and dependent on the impervious coverage for a site.
WATER QUALITY REQUIREMENTS
As defined under state regulations-protection of designated and existing uses (Refer 25 Pa. Code, Chapters 93 and 96):
(1) 
Each stream segment in Pennsylvania has a "designated use," such as "cold water fishery" or "potable water supply," which are listed in 25 Pa. Code, Chapter 93. These uses must be protected and maintained, under state regulations.
(2) 
"Existing uses" are those attained as of November, 1975, regardless whether they have been designated in 25 Pa. Code, Chapter 93. Land development must be designed to protect and maintain existing uses and maintain the level of water quality necessary to protect those uses in all streams, and to protect and maintain water quality in special protection streams.
(3) 
Water quality involves the chemical, biological and physical characteristics of surface water bodies. After land development, these characteristics can be impacted by addition of pollutants such as sediment, and changes in habitat through increased flow volumes and/or rates. Therefore, discharge to surface waters must be designed and managed to protect the streambank, streambed and structural integrity of the waterway, to prevent these impacts.
WATER QUALITY VOLUME
A calculated volume of stormwater runoff from impervious areas which is required to be captured and treated at a site and may be achieved through use of structural or non-structural BMPs.
WATERCOURSE
An intermittent, ephemeral or perennial stream of water, river, brook, creek or swale identified on USGS or SCS mapping; and/or delineated waters of the commonwealth.
WATERS OF THE COMMONWEALTH
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.
[Amended by Ord. No. 2022-005, 9/6/2022]
WATERSHED
Region or area drained by a river, watercourse, or other surface water of this Commonwealth.
[Amended by Ord. No. 2022-005, 9/6/2022]
WET POND (WET EXTENDED DETENTION POND)
A wet extended pond combines the pollutant removal effectiveness of a permanent pool of water with the flow reduction capabilities of an extended storage volume.
WETLAND
Those 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, ferns and similar areas.
WETLAND DELINEATION
The on-site method or process for identifying wetlands. Wetlands must be delineated by a qualified specialist according to the 1989 Federal Manuals (as amended) for the Delineation of Jurisdictional Wetlands (whichever is greater) or according to any subsequent federal or state regulation. Qualified specialist shall include those persons being Certified Professional Soil Scientists as registered with Registry of Certified Professionals in Agronomy Crops and Soils (ARCPACS); or as contained on consultant's list of Pennsylvania Association of Professional Soil Scientists (PAPSS); or as registered with National Society of Consulting Soil Scientists (NSCSS), or as certified by state and/or federal certification programs; or by a qualified biologist/ecologist.
[1]
Editor's Note: The former definition of "design professional (qualified)," which immediately followed, was repealed by Ord. No. 2022-005, 9/6/2022.
[2]
Editor's Note: This ordinance also renumbered these definitions to be included under Subsection F.
[3]
Editor’s Note: See 35 P.S. § 691.1 et seq.