For the purposes of this article, certain terms and words used herein
shall be interpreted as follows:
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.
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.
The words "shall" and "must" are mandatory; the words "may"
and "should" are permissive.
The words "used or occupied" include the words "intended, designed,
maintained, or arranged to be used or occupied."
ACCELERATED EROSION
The removal of the surface of the land through the combined
action of man's activity and the natural processes of a rate
greater than would occur because of the natural process alone.
AGRICULTURAL ACTIVITY
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.
ALTERATION
As applied to land, a change in topography because of the
moving of soil and rock from one location or position to another;
also the changing of surface conditions by causing the surface to
be 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 Earth Disturbance activity
at a project site in the Municipality.
BANK FULL
The channel at the top-of-bank or point where water begins
to overflow onto a floodplain.
BASE FLOW
Portion of stream discharge derived from groundwater; the
sustained discharge that does not result from direct runoff or from
water diversions, reservoir releases, piped discharges, or other human
activities.
BIORETENTION
A Stormwater retention area that 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 promote groundwater recharge and to
otherwise meet the purposes of this article. BMPs include but are
not limited to infiltration, filter strips, low impact design, bioretention,
wet ponds, permeable paving, grassed swales, forested buffers, sand
filters and detention basins. Structural SWM BMPs are permanent appurtenances
to the project site.
CARBONATE BEDROCK (AREAS)
Rock consisting chiefly of carbonate minerals, such as limestone
and dolomite; specifically a sedimentary rock composed of more than
50% by weight of carbonate minerals that underlies soil or other unconsolidated,
superficial material.
CHANNEL
A drainage element in which Stormwater flows with an open
surface. Open channels include, but shall not be limited to, natural
and man-made drainage ways, swales, streams, ditches, canals, and
pipes flowing partly full.
CHANNEL EROSION
The widening, deepening, and headward cutting of small channels
and waterways, caused by Stormwater runoff or bank full flows.
CISTERN
An underground reservoir or tank for storing rainwater.
CONSERVATION DISTRICT
A conservation district, as defined in Section 3(c) of the
Conservation District Law (3 P.S. § 851(c)), which has the
authority under a delegation agreement executed with the Department
to administer and enforce all or a portion of the erosion and sediment
control program in this Commonwealth.
CULVERT
A structure with appurtenant works, which carries water under
or through an embankment or fill.
DAM
An artificial barrier, together with its appurtenant works,
constructed for the purpose of impounding or storing water or another
fluid or semi fluid, or a refuse bank, fill or structure for highway,
railroad or other purposes which does or may impound water or another
fluid or semi fluid.
DELINEATION
The process of determining a wetland's physical boundaries.
DESIGN STORM
The magnitude and temporal distribution of precipitation
from a storm event measured in probability of occurrence (e.g. a five-year
storm) and duration (e.g. 24 hours), used in the design and evaluation
of Stormwater management systems. (See Return Period)
DESIGNEE
The agent of the Lawrence County Planning Commission, Lawrence
County Conservation District and/or agent of the governing body involved
with the administration, review or enforcement of any provisions of
this article by contract or memorandum of understanding.
DETENTION
The volume of runoff that is captured and released into the
Waters of this Commonwealth at a controlled rate.
DETENTION BASIN
An impoundment designed to collect and attenuate Stormwater
peak runoff by temporarily storing the runoff and releasing it at
a predetermined rate. Detention basins are designed to drain completely
shortly after any given rainfall event and are dry until the next
rainfall event.
DEVELOPMENT
See "Earth Disturbance Activity." The term includes redevelopment.
DISCHARGE
To release water from a project, site, aquifer, drainage
basin or other point of interest (verb); The rate and volume of flow
of water such as in a stream, generally expressed in cubic feet per
second (volume per unit of time) (noun). See also Peak Discharge.
DISCONNECTED IMPERVIOUS AREA (DIA)
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 as specified in Appendix E, Disconnected
Impervious Area.
DISTURBED AREA
An unstabilized land area where an earth disturbance activity
is occurring or has occurred.
DOWN SLOPE PROPERTY LINE
That portion of the property line of the lot, tract, or parcels
of land being developed located such that overland or pipe flow from
the site would flow towards it.
DRAINAGE EASEMENT
A right granted by a landowner to a grantee, allowing the
use of private land for Stormwater management purposes.
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, road maintenance, building construction
and the moving, depositing, stockpiling, or storing of soil, rock
or earth materials.
EMERGENCY SPILLWAY
A conveyance area that is used to pass peak discharge greater
than the maximum design storm controlled by a Stormwater Management
facility.
ENCROACHMENT
A structure or activity that changes, expands, or diminishes
the course, current or cross section of a watercourse, floodway, floodplain,
or body of water.
EPHEMERAL STREAM
A stream with flowing water only during, and for a short
duration after, precipitation events in a typical year. Ephemeral
streambeds are located above the water table year-round. Groundwater
is not a source of water for the stream. Runoff from rainfall is the
primary source of water for stream flow.
EROSION
The natural process by which the surface of the land is worn
away by water, wind or chemical action.
EXCEPTIONAL VALUE WATERS
Surface waters of high quality which satisfy Pennsylvania
Code Title 25 Environmental Protection, Chapter 93, Water Quality
Standards, § 93.4b(b) (relating to anti-degradation).
EXISTING CONDITION
The dominant land cover during the five year period immediately
preceding a proposed Regulated Activity.
EXTENDED DETENTION VOLUME (EDV)
Release of detained runoff in excess of Permanently Removed
Volume (PRV) over a period of time not less than 24 and not more than
72 hours.
FELLING
The process of cutting down standing trees.
FLOOD
A temporary condition of partial or complete inundation of
land areas from the overflow of streams, rivers, and other waters
of this Commonwealth.
FLOODPLAIN
Any land area susceptible to inundation by water from any
natural source or delineated by applicable Federal Emergency Management
Agency (FEMA) maps and studies as being a special flood hazard area.
Also included are areas that comprise Group 13 Soils, as listed in
Appendix A of the Pennsylvania Department of Environmental Protection
(PA DEP) Technical Manual for Sewage Enforcement Officers (as amended
or replaced from time to time by PA DEP).
FLOODWAY
The channel of the watercourse and those portions of the
adjoining floodplain that is reasonably required to carry and discharge
the 100-year flood. Unless otherwise specified, the boundary of 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, the floodway includes floodplain
areas within 50 feet of the top of each stream bank and the stream
channel itself.
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 elevation and the top of a dam, levee, tank, basin, swale, or
diversion berm. The space is required as a safety margin in a pond
or basin.
GRADE
A slope, usually of a road, channel or natural ground specified
in percent and shown on plans as specified herein. (To) Grade - To
finish the surface of a roadbed, top of embankment or bottom of excavation.
GRASSED WATERWAY
A natural or constructed waterway, usually broad and shallow,
covered with erosion-resistant grasses, used to convey surface water.
GROUNDWATER
Water beneath the earth's surface, often between saturated
soil and rock that supplies wells and springs.
GROUNDWATER RECHARGE
Replenishment of existing natural underground water supplies
without degrading groundwater quality.
HARVESTING
The felling, skidding, loading, and transporting of timber
products.
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 Pennsylvania Code Title 25 Environmental
Protection, Chapter 93 Water Quality Standards, § 93.4b(a).
HYDRIC SOILS
Soils that are characterized by the presence of water.
HYDROGRAPH
A graph of stormwater or runoff discharge versus time for
a selected point in the drainage system.
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 underlying the project 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.
IMPERVIOUS SURFACE (IMPERVIOUS AREA)
A surface that prevents the infiltration of water into the
ground. Impervious surfaces (or covers) shall include, but not be
limited to:
(1)
Roofs, additional indoor living spaces, patios, garages, storage
sheds and similar structures.
(2)
New streets or sidewalks, decks, parking areas, and driveway
areas using traditional paved surfaces that prevent infiltration into
the ground. New decks, parking areas, and driveways are not defined
as impervious areas if they are designed to allow long-term infiltration.
(3)
Existing gravel parking areas, driveways, and roads shall be
treated as slightly pervious and shall be analyzed using the appropriate
SCS curve number based on their HSG; proposed gravel parking areas,
driveways, and roads shall be treated as impervious areas for all
calculations.
IMPOUNDMENT
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, evaporates into the atmosphere, or percolates downward
to recharge groundwater.
INFILTRATION STRUCTURES
A structure designed to direct runoff into the groundwater
(e.g., French drains, seepage pits, and seepage trench).
INLET
The upstream end of any structure through which water may
flow.
INTERMITTENT STREAM
A stream with flowing water during certain times of the year,
when groundwater provides water for stream flow. During dry periods,
intermittent streams may not have flowing water. Runoff from rainfall
is a supplemental source of water for stream 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 (DEVELOPMENT)
Any of the following activities:
(1)
The improvement of one lot 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 proposed initially or cumulatively, or a single nonresidential
building on a lot or lots regardless of the number of occupants or
tenure; or
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.
LANDING (or DECK)
A place where logs or tree-length materials are assembled
for loading and transport.
LITTER LAYER
The layer of fallen leaves, twigs, and decaying woody material
that provides a sponge-like mat covering forest soils.
LOT
A part of a subdivision or a parcel of land used as a building
site or intended to be used for building purposes, whether immediate
or future, which would not be further subdivided.
MAIN STEM (MAIN CHANNEL)
Any stream segment or other runoff conveyance facility used
as a reach in the hydrologic model.
MANNING EQUATION (MANNING FORMULA)
A method for calculation of velocity of flow (e.g., feet
per second) and flow rate (e.g., cubic feet per second) in open channels
based upon channel shape, roughness, depth of flow and slope. "Open
channels" may include closed conduits so long as the flow is not under
pressure.
MUNICIPAL ENGINEER
A professional engineer licensed as such in the Commonwealth
of Pennsylvania, duly appointed as the engineer for a Municipality,
planning agency or joint planning commission.
MUNICIPALITY
City of New Castle, Lawrence County, Pennsylvania.
NATURAL RECHARGE AREA
Undisturbed surface area or depression where Stormwater collects,
and a portion of which infiltrates and replenishes the underground
and groundwater.
NON-POINT SOURCE POLLUTION
Pollution that enters a water body from diffuse origins in
the watershed and does not result from discernible, confined, or discrete
conveyances.
NON-STRUCTURAL BEST MANAGEMENT PRACTICE (BMPs)
Methods of controlling Stormwater runoff quantity and quality,
such as innovative site planning, impervious area and grading reduction,
protection of natural depression areas, temporary ponding on site
and other techniques.
NPDES
National Pollutant Discharge Elimination System, the federal
government's system for issuance of permits under the Clean Water
Act, which is delegated to PA DEP in Pennsylvania.
NRCS
Natural Resources Conservation Service (previously SCS).
OUTFALL
"Point source" as described in 40 CFR § 122.2 at
the point 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 drain.
PA DEP
The Pennsylvania Department of Environmental Protection.
PA DOT
Pennsylvania Department of Transportation.
PARENT TRACT
The parcel of land from which a land development or subdivision
originates, determined from the date of Municipal adoption of this
article.
PARKING LOT STORAGE
The use of parking areas as temporary impoundments with controlled
release rates during rainstorms.
PEAK DISCHARGE
The maximum rate of Stormwater runoff from a specific storm
event.
PERMANENTLY REMOVED VOLUME (PRV)
The volume of runoff that is permanently removed from the
runoff and not released into surface Waters of this Commonwealth during
or after a storm event.
PIPE
A culvert, closed conduit, or similar structure (including
appurtenances) that conveys Stormwater.
PLANNING COMMISSION
The municipal or County planning commission authorized under
the Pennsylvania Municipalities Planning Code.
POINT SOURCE
Any discernible, confined and discrete conveyance, including,
but not limited to, any pipe, ditch, channel, tunnel, or conduit from
which Stormwater is or may be discharged, as defined in State regulations
at 25 Pa. Code § 92.1.
POST-CONSTRUCTION
Period after construction where disturbed areas are stabilized,
Stormwater controls are in place and functioning and all proposed
improvements in the approved land development plan are completed.
PRE-TREATMENT
Techniques employed in Stormwater BMPs to provide storage
or filtering to trap coarse materials and other pollutants before
they enter the system.
PROJECT SITE
The specific area of land where any Regulated Activities
in the Municipality are planned, conducted, or maintained.
QUALIFIED PROFESSIONAL
A Professional Engineer licensed by the Pennsylvania Department
of State or otherwise qualified by law to perform the engineering
work required by the Article.
RECHARGE
The replenishment of groundwater through the infiltration
of rainfall or Stormwater runoff.
RECORD DRAWINGS
Those drawings maintained by the Applicant, Applicant's
Contractor, or Applicant's Agent as the Applicants project is
constructed; and upon which is documented the actual locations of
the building components and changes to the original contract documents.
These, or a copy of same, are turned over to the Municipality at the
completion of the project.
REDEVELOPMENT
The demolition, construction, reconstruction, alteration,
or improvement exceeding 2,000 square feet of land disturbance performed
on sites where existing land use is commercial, industrial, institutional,
or multifamily residential. Maintenance activities such as top-layer
grinding and re-paving are not considered redevelopment. Interior
remodeling projects and tenant improvements are also not considered
redevelopment. Utility trenches in streets are not considered redevelopment
unless more than 50% of the street width is removed and re-paved.
REGULATED ACTIVITIES
All activities involving land development or earth disturbance
activity that may affect stormwater runoff.
RELEASE RATE
The percentage of existing conditions 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 structure in which Stormwater is stored and not released
during the storm event. Retention Basins do not function without operational
intervention to release stored Stormwater unless designed as infiltration-only
basins.
RETENTION/REMOVED
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 interval, in years, within which a storm event of a given
magnitude can be expected, on average, to recur. For example, the
twenty-five-year return period rainfall would be expected, on average,
to recur every 25 years. The probability of a twenty-five-year storm
occurring in any one year is 0.04 or 4%.
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 cross-section,
such as grading and repairing existing unpaved road surfaces, cutting
road banks, cleaning or clearing drainage ditches and other similar
activities.
ROOF DRAINS
A drainage conduit or pipe that collects water runoff from
a roof and leads it away from the structure.
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.
SALDO
Subdivision and Land Development Ordinance.
SCS
Soil Conservation Service (currently known as NRCS, Natural
Resources Conservation Service). Also a commonly referred to method
("SCS Method") for the hydrologic computation and estimation of runoff
from rainfall information that has been developed by the United States
Department of Agriculture's Soil Conservation Service (SCS).
SEDIMENT
Soils or other materials transported by surface water as
a product of erosion.
SEDIMENT BASIN
A barrier, dam, retention or detention basin located and
designed to retain rock, sand, gravel, silt, or other material transported
by water during construction.
SEDIMENT POLLUTION
The placement, discharge or any other introduction of sediment
into the waters of the Commonwealth.
SEDIMENTATION
The process by which mineral or organic matter is accumulated
or deposited by the movement of water or air.
SEEPAGE PIT/SEEPAGE TRENCH
An area of excavated earth filled with loose stone or similar
coarse material, into which surface water is directed for infiltration
into the groundwater.
SEPARATE STORM SEWER SYSTEM
A conveyance or system of conveyances (including roads with
drainage systems, Municipal streets, catch basins, curbs, gutters,
ditches, man-made channels or storm drains) primarily used for collecting
and conveying Stormwater runoff.
SHALLOW CONCENTRATED FLOW
Stormwater runoff flowing in shallow, defined rills prior
to entering a defined channel or waterway.
SHEET FLOW
A flow process associated with broad, shallow water movement
on sloping ground surfaces that is not channelized or concentrated.
SKID ROAD/HAUL ROAD
Those roads, trails, or other openings upon which trees,
logs, equipment, or vehicles are moved within the site of the work.
SKIDDING
Moving of logs or felled trees along the surface of the ground
from the stump to the point of loading.
SLASH
Unusable woody material such as large limbs, tops, cull logs,
and stumps that remain after timber harvesting.
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).
SPECIAL GEOLOGIC FEATURES
Carbonate bedrock features, including but not limited to
closed depressions, existing sinkholes, fracture traces, lineaments,
joints, faults, caves and pinnacles, which may exist and must be identified
on a site when Stormwater management BMPs are being considered.
SPILLWAY
A conveyance that is used to pass the peak discharge of the
maximum design storm controlled by the Stormwater facility.
STATE WATER QUALITY REQUIREMENTS
The regulatory requirements to protect, maintain, reclaim,
and restore water quality under Pennsylvania Code Title 25 and the
Clean Streams Law.
STORAGE INDICATION METHOD
A reservoir routing procedure based on solution of the continuity
equation (inflow minus outflow equals the change in storage) with
outflow defined as a function of storage volume and depth.
STORM FREQUENCY
The number of times that a given storm "event" occurs or
is exceeded on the average in a stated period of years. See "Return
Period."
STORM SEWER
A system of pipes and/or open channels that convey intercepted
runoff and Stormwater from other sources, but exclude domestic sewage
and industrial wastes.
STORMWATER
Drainage runoff from the surface of the land resulting from
precipitation or snow or ice melt.
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, and infiltration structures.
STORMWATER MANAGEMENT PLAN
The plan for managing Stormwater runoff adopted by the County
of Lawrence as required by the Act of October 4, 1978, P.L. 864, (Act
167), as amended, and known as the "Stormwater Management Act."
STORMWATER MANAGEMENT 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 article. Stormwater Management Site Plan will
be designated as SWM Site Plan throughout this article.
STREAM ENCLOSURE
A bridge, culvert or other structure in excess of 100 feet
in length upstream to downstream that encloses a regulated water of
this Commonwealth.
SUBAREA (SUB-WATERSHED)
The smallest drainage unit of a watershed for which Stormwater
management criteria have been established in the Stormwater Management
Plan.
SUBDIVISION
The division or re-division of a lot, tract or parcel of
land by any means into two or more lots, tracts, parcels or other
divisions of land including changes in existing lot lines for the
purpose, whether immediate or future, of lease, partition by the court
for distribution to heirs or devisees, transfer of ownership or building
or lot development (Refer to the PA Municipalities Planning Code,
current version.)
SURFACE WATERS OF THE/THIS COMMONWEALTH
Any and all rivers, streams, creeks, rivulets, ditches, watercourses,
storm sewers, lakes, dammed water, wetlands, ponds, springs, and all
other bodies or channels of conveyance of surface, or parts thereof,
whether natural or artificial, within or on the boundaries of this
Commonwealth.
SWALE
A low-lying stretch of land that 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.
USACE
United States Army Corp of Engineers.
VERNAL POND
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.
WATERCOURSE
A channel or conveyance of surface water having defined bed
and banks, whether natural or artificial, with perennial or intermittent
flow.
WATERS OF THE/THIS 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 this Commonwealth.
WATERSHED
Region or area drained by a river, watercourse or other body
of water, whether natural or artificial.
WET BASIN
A detention basin that is designed to detain Stormwater and
which always contains water.
WETLAND
Those areas that are inundated or saturated by surface or
ground water at a frequency and duration sufficient to support, and
that under normal circumstances do support, a prevalence of vegetation
typically adapted for life in saturated soil conditions, including
swamps, marshes, bogs, fens, and similar areas.