A. 
For the purpose of this Part 1, certain terms and words used herein shall be interpreted as follows:
(1) 
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.
(2) 
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.
(3) 
The word "person" includes an individual, firm, association, organization, partnership, trust, company, corporation, or any other similar entity.
(4) 
The words "shall" and "must" are mandatory; the words "may" and "should" are permissive.
(5) 
The words "used or occupied" include the words "intended, designed, maintained, or arranged to be used, occupied or maintained."
B. 
For the purpose of this Part 1, the following terms shall have the meanings indicated:
ACCELERATED EROSION
The removal of the surface of the land through the combined action of human activity and natural processes at a rate greater than would occur because of the natural process alone.
ACT 167
See "Storm Water Management Act."[1]
ACT 167 PLAN
The plan for managing stormwater throughout a designated watershed adopted by Butler County as required by the Storm Water Management Act.
AGRICULTURAL ACTIVITIES
Activities associated with agriculture such as agricultural cultivation, agricultural operation, and animal heavy use areas. This includes the work of producing crops, 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.
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; changing of surface conditions by causing the surface to be more or less impervious; land disturbance.
APPLICANT
A landowner, developer, or other person who has filed an application for approval to engage in any regulated activities at a project site within the Township.
ARMY CORPS OF ENGINEERS (ACOE)
The United States Army Corps of Engineers or any agency successor thereto.
BEST MANAGEMENT PRACTICES (BMPs)
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: "nonstructural" or "structural." "Nonstructural" BMPs are measures referred to as operational and/or behavior-related practices that attempt to minimize the contact of pollutants with stormwater runoff whereas "structural" BMPs are measures 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.
BMP MANUAL
The Pennsylvania Department of Environmental Protection's Stormwater Best Management Practices (BMP) Manual, most recent edition.
BOARD OF SUPERVISORS
The Board of Supervisors of Jackson Township, Butler County, Pennsylvania.
CHANNEL EROSION
The widening, deepening, and headward cutting of small channels and waterways, due to erosion caused by moderate to large floods.
CISTERN
An underground reservoir or tank used for storing rainwater.
CLEAN STREAMS LAW
The Pennsylvania Clean Streams Law, 35 P.S. § 691.1 et seq., as amended.
CONSERVATION DISTRICT
The Butler County Conservation District. The Butler County Conservation District has the authority under a delegation agreement executed with the Department of Environmental Protection to administer and enforce all or a portion of the regulations promulgated under 25 Pa. Code Chapter 102.
CULVERT
A structure with appurtenant works that carries a stream and/or stormwater runoff 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 semifluid.
DESIGNEE
The agent of this Township and/or agent of the Board of Supervisors involved with the administration, review or enforcement of any provisions of this Part 1 by contract or memorandum of understanding.
DESIGN STORM
The magnitude and temporal distribution of precipitation from a storm event measured in probability of occurrence (e.g., a twenty-five-year storm) and duration (e.g., 24 hours), used in the design and evaluation of stormwater management systems. Also see "return period."
DETENTION BASIN
An impoundment structure designed to manage stormwater runoff by temporarily storing the runoff and releasing it at a predetermined rate.
DETENTION VOLUME
The volume of runoff that is captured and released into waters of the commonwealth at a controlled rate.
DEVELOPER
As defined in the Subdivision and Land Development Ordinance (Chapter 22).
DEVELOPMENT SITE (SITE)
The specific area of land for which a regulated activity is proposed. Also see "project site."
DISTURBED AREA
An 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 located such that all overland or pipe flow from the site would be directed toward it.
DRAINAGE CONVEYANCE FACILITY
A stormwater management facility designed to convey stormwater runoff and 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, drainage, or conveyance purposes.
DRAINAGEWAY
Any natural or artificial watercourse, trench, ditch, pipe, swale, channel, or similar depression into which surface water flows.
E&S MANUAL
The Pennsylvania Department of Environmental Protection Erosion and Sediment Pollution Control Program Manual, No. 363-2134-008 (April 15, 2000), as amended and updated.
EARTH DISTURBANCE ACTIVITY
A construction or other human activity which disturbs the surface of the land, including, but not limited to, clearing and grubbing, grading, excavations, embankments, land development, agricultural plowing or tilling, timber harvesting activities, road maintenance activities, mineral extraction, and the moving, depositing, stockpiling, or storing of soil, rock or earth materials.
EROSION
The movement of soil particles by the action of water, wind, ice, or other natural forces.
EROSION AND SEDIMENT POLLUTION CONTROL PLAN
A plan which is designed to minimize accelerated erosion and sedimentation.
EXCEPTIONAL-VALUE WATERS
Surface waters of high quality, which satisfies 25 Pa. Code, "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 construction. If the initial condition of the site is undeveloped land and not forested, the land use shall be considered as meadow, unless the natural land cover is documented to generate lower curve numbers or rational "C" coefficient.
FEMA
The Federal Emergency Management Agency, or its successor entity.
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 the commonwealth.
FLOOD-FRINGE
The remaining portions of the one-hundred-year floodplain outside of the floodway boundary.
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 Maps as being a special flood hazard area. Included are lands adjoining a river or stream that have been or may be inundated by a one-hundred-year flood. 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 landward from the top of the bank of the stream.
FOREST MANAGEMENT/TIMBER OPERATIONS
Planning and activities necessary for the management of forestland. These include timber inventory and preparation of forest management plans, silvicultural treatment, cutting budgets, logging road design and construction, timber harvesting, site preparation and reforestation.
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 tank, pond or basin.
GRADE
(1) 
GRADEA slope, usually of a road, channel or natural ground, specified in percent and shown on plans as specified herein.
(2) 
TO) GRADE To finish the surface of a roadbed, top of embankment or bottom of excavation.
GROUNDWATER RECHARGE
Replenishment of existing natural underground water supplies.
HEC-HMS MODEL CALIBRATED (HYDROLOGIC ENGINEERING CENTER-HYDROLOGIC MODELING SYSTEM)
A computer-based hydrologic modeling technique adapted to the watershed(s) in Butler County for the Act 167 Plan. The model has been calibrated by adjusting key model input parameters.
HIGH-QUALITY WATERS
Surface water 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, "Environmental Protection," Chapter 93, "Water Quality Standards," § 93.4b(a).
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 one of four HSG (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 United States 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 interest may be identified from a soil survey report from the local NRCS office or the County Conservation District.
IMPERVIOUS SURFACE (IMPERVIOUS AREA)
A surface that prevents the infiltration of water into the ground. Impervious surface (or area) includes but is not limited to roofs, additional indoor living spaces, patios, garages, storage sheds and similar structures, parking or driveway areas, and any new streets and sidewalks. Any surface areas proposed to initially be gravel or crushed stone shall be assumed to be impervious surfaces.
IMPOUNDMENT
A retention or detention basin designed to retain stormwater runoff and release it at a controlled rate.
INFILTRATION STRUCTURES
A structure designed to direct runoff into the ground (e.g., french drains, seepage pits, seepage trench, etc.).
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.
LAND DEVELOPMENT (DEVELOPMENT)
As defined in the Subdivision and Land Development Ordinance (Chapter 22).
LANDOWNER
As defined in the Subdivision and Land Development Ordinance (Chapter 22).
LEVEL SPREADER
A site-specific stormwater management measure or measures that reduce the erosive energy of concentrated flows by distributing runoff as sheet flow to stabilized vegetated surfaces. Level spreaders also may promote infiltration and improve water quality if designed, constructed and maintained properly.
LOW-IMPACT DEVELOPMENT (LID)
An approach to land development that uses various land planning and design practices and technologies to simultaneously conserve and protect natural resource systems and reduce infrastructure costs. LID still allows land to be developed, but in a cost-effective manner that helps mitigate potential environmental impacts.
MAIN STEM (MAIN CHANNEL)
Any stream segment or other runoff conveyance facility used as a reach in the Butler County Act 167 watershed hydrologic model(s).
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.
MUNICIPALITIES PLANNING CODE (MPC)
The Pennsylvania Municipalities Planning Code, 53 P.S. § 10101 et seq., as amended.
NATIONAL POLLUTANT DISCHARGE ELIMINATION SYSTEM (NPDES)
The federal government's system for issuance of permits under the Clean Water Act,[2] which is delegated to PADEP in Pennsylvania.
NOAA ATLAS 14
Precipitation-Frequency Atlas of the United States, Atlas 14, Volume 2, United States Department of Commerce, National Oceanic and Atmospheric Administration, National Weather Service, Hydrometeorological Design Studies Center, Silver Spring, Maryland (2004). NOAA's Atlas 14 can be accessed at Internet address http://hdsc.nws.noaa.gov/hdsc/pfds/.
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.
NRCS
Natural Resources Conservation Service [previously "Soil Conservation Service (SCS)"], or its successor agency.
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 not under pressure.
OUTFALL
(1) 
Point where water flows from a conduit, stream, or drain;
(2) 
"Point source" as described in 40 CFR 122.2 at the point where the Township's storm sewer system discharges to surface waters of the commonwealth.
OUTLET
Points of water disposal from a stream, river, lake, tidewater, or artificial drain.
PADEP
See "Pennsylvania Department of Environmental Protection."
PARKING LOT STORAGE
Involves the use of impervious parking areas as temporary impoundments with controlled release rates during rainstorms.
PEAK DISCHARGE
The maximum rate of stormwater runoff from a specific storm event.
PENNSYLVANIA DEPARTMENT OF ENVIRONMENTAL PROTECTION (PADEP)
The Department of Environmental Protection of the Commonwealth of Pennsylvania or any agency successor thereto.
PENNSYLVANIA DEPARTMENT OF TRANSPORTATION (PENNDOT)
The Pennsylvania Department of Transportation of the Commonwealth of Pennsylvania or any agency successor thereto.
PERSON
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.
PERVIOUS AREA
Any area not defined as impervious.
PIPE
A culvert, closed conduit, or similar structure (including appurtenances) that conveys stormwater.
POINT SOURCE
Any discernible, confined, or 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.[3]
PROBABLE MAXIMUM FLOOD (PMF)
The flood that may be expected from the most severe combination of critical meteorological 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 (NOAA).
PROJECT SITE
The specific area of land where any regulated activities in the Township are planned, conducted, or maintained.
QUALIFIED PROFESSIONAL
Any person licensed by the Pennsylvania Department of State or otherwise qualified by law to perform the work required by this Part 1.
RATIONAL FORMULA
A rainfall-runoff relation used to estimate peak flow.
REDEVELOPMENT
Earth disturbance activities on land which has previously been developed.
REGULATED ACTIVITIES
Any earth disturbance activities or any activities that involve the alteration or development of land in a manner that may affect stormwater runoff. Regulated activities include but are not limited to the following listed items:
(1) 
Earth disturbance activities.
(2) 
Land development.
(3) 
Subdivision.
(4) 
Construction of new or additional impervious or semipervious surfaces.
(5) 
Construction of new buildings or additions to existing buildings.
(6) 
Diversion or piping of any natural or man-made stream channel.
(7) 
Installation of stormwater management facilities or appurtenances thereto.
(8) 
Installation of stormwater BMPs.
REGULATED EARTH DISTURBANCE ACTIVITY
Activity involving earth disturbance subject to regulation under 25 Pa. Code Chapter 92,[4] Chapter 102, or the Clean Streams Law.[5]
RELEASE RATE
The percentage of predevelopment peak rate of runoff from a site or subwatershed area to which the post-development peak rate of runoff must be reduced to protect downstream areas.
RELEASE RATE DISTRICT
Those subwatershed areas in which post-development flows must be reduced to a certain percentage of predevelopment flows as required to meet the plan requirements and the goals of Act 167.
RETENTION BASIN
An impoundment in which stormwater is stored and not released during the storm event. Stored water may be released from the basin at some time after the end of the storm.
RETENTION VOLUME/REMOVED 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.
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; or stated in another way, the probability of a twenty-five-year storm occurring in any one given year is 0.04 (i.e., a four-percent chance).
RIPARIAN BUFFER
A vegetated area bordering perennial and intermittent streams and wetlands that serves as a protective filter to help protect streams/wetlands from the impacts of adjacent land uses.
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 the existing road right-of-way, such as grading and repairing existing unpaved road surfaces, cutting road banks, cleaning or clearing drainage ditches, and other similar activities. Road maintenance activities that do not disturb the subbase of a paved road (such as milling and overlays) are not considered earth disturbance activities.
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.
RUNOFF CAPTURE VOLUME
The volume of runoff that is captured (retained) and not released into surface waters of the commonwealth during or after a storm event.
SEDIMENT
Soils or other materials transported by surface water as a product of erosion.
SEDIMENTATION
The process by which mineral or organic matter is accumulated or deposited by the movement of water.
SEDIMENT BASIN
A barrier, dam, retention or detention basin located and designed to retain rock, sand, gravel, silt, or other material transported by stormwater runoff.
SEDIMENT POLLUTION
The placement, discharge, or any other introduction of sediment into waters of the commonwealth occurring from the failure to properly design, construct, implement or maintain control measures and control facilities in accordance with the requirements of this Part 1.
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 ground.
SEPARATE STORM SEWER SYSTEM
A conveyance or system of conveyances (including roads with drainage systems, municipal streets, catch basins, curbs, gutters, ditches, man-made channels, or storm drains) primarily used for collecting and conveying stormwater runoff.
SHEET FLOW
Runoff that flows over the ground surface as a thin, even layer, not concentrated in a channel.
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).
SPILLWAY (EMERGENCY)
A depression in the embankment of a pond or basin, or other overflow structure, that is used to pass peak discharges greater than the maximum design storm controlled by the pond or basin.
STATE WATER QUALITY REQUIREMENTS
The regulatory requirements to protect, maintain, reclaim, and restore water quality under Title 25 of the Pennsylvania Code and the Clean Streams Law, 35 P.S. § 691.1 et seq.
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 also "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
Runoff from the surface of the land resulting from precipitation, snow, or ice melt.
STORMWATER HOTSPOT
A land use or activity that generates higher concentrations of hydrocarbons, trace metals, or toxicants than are found in typical stormwater runoff.
STORM WATER MANAGEMENT ACT
The Pennsylvania Storm Water Management Act, 32 P.S. § 680.1 et seq.
STORMWATER MANAGEMENT FACILITIES
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.
STORMWATER MANAGEMENT PLAN
The Butler County Stormwater Management Plan for managing stormwater runoff in Butler County as required by Act 167.
STORMWATER MANAGEMENT SITE PLAN (SWM SITE PLAN)
The plan prepared by the applicant or his representative indicating how stormwater runoff will be managed at the project site in accordance with this Part 1.
STREAM ENCLOSURE
A bridge, culvert, or other structure in excess of 100 feet in length upstream to downstream which encloses regulated waters of the commonwealth.
SUBDIVISION
Chapter 22, Subdivision and Land Development, of the Code of Jackson Township, Butler County, Pennsylvania, as amended.
SUBWATERSHED AREA
The smallest drainage unit of a watershed for which stormwater management criteria has been established in the stormwater management plan.
SWALE
A low-lying stretch of land that 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
Jackson Township, Butler County, Pennsylvania.
TOWNSHIP ENGINEER
The professional engineer licensed as such in the Commonwealth of Pennsylvania and duly appointed as the Engineer of the Township or his designee.
TOWNSHIP PLANNING COMMISSION
The Planning Commission of Jackson Township.
USDA
The United States Department of Agriculture, or its successor entity.
WATERCOURSE
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.
WATERSHED
Area drained by a river, watercourse, or other surface water, whether natural or artificial.
WATERS OF THE COMMONWEALTH
Rivers, streams, creeks, rivulets, impoundments, ditches, watercourses, storm sewers, lakes, dammed water, wetlands, ponds, springs and other bodies or channels of conveyance of surface and underground water, or parts thereof, whether natural or artificial, within or on the boundaries of the Commonwealth of Pennsylvania.
WETLAND
Those areas that are inundated or saturated by surface water 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. (The term includes, but is not limited to, wetland areas listed in the state water plan, the United States Forest Service Wetlands Inventory of Pennsylvania and a wetland area designated by a river basin commission. This definition is used by the United States Environmental Protection Agency and the United States Army Corps of Engineers.)
ZONING ORDINANCE
Chapter 27, Zoning, of the Code of Jackson Township, Butler County, Pennsylvania, as amended.
[1]
Editor's Note: See 32 P.S. § 680.1 et seq.
[2]
Editor's Note: See 33 U.S.C. § 1251 et seq.
[3]
Editor's Note: Chapter 92 of Title 25 of the Pennsylvania Code was reserved 10-8-2010, effective 10-9-2010. See now 25 Pa. Code § 92a.2.
[4]
Editor's Note: Chapter 92 of Title 25 of the Pennsylvania Code was reserved 10-8-2010, effective 10-9-2010. See now Chapter 92a, National Pollutant Discharge Elimination System Permitting, Monitoring and Compliance.
[5]
Editor's Note: See 35 P.S. § 691.1 et seq.