[Ord. No. 6-2014, 15, passed 11-24-2014]
For the purpose of this article, 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 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)
The words "watershed," "subwatershed" and "drainage area" are
synonymous and refer to the contributing area of interest.
(g)
ACCELERATED EROSION
AGRICULTURAL ACTIVITIES
ALTERATION
APPLICANT
BAFFLES
BASE FLOOD
BEST MANAGEMENT PRACTICES (BMPs)
BIORETENTION
BMP MANUAL
BRIDGE
CARBONATE GEOLOGY
CHECK DAM
CITY
CITY COUNCIL
COMMONWEALTH
CONSERVATION DISTRICT
CONSTRUCTION
CONVEYANCE
COUNTY
CULVERT
DAM
DEP (or PADEP)
DESIGN STORM
DETENTION BASIN
DETENTION POND
DETENTION VOLUME
DEVELOPER
DEVELOPMENT
DISTURBED AREA
DOWNSLOPE PROPERTY LINE
DRAINAGE CONVEYANCE FACILITY
DRAINAGE EASEMENT
EARTH DISTURBANCE ACTIVITY
ENERGY DISSIPATER
ENGINEER, CITY
EROSION
EROSION AND SEDIMENTATION POLLUTION CONTROL PLAN
EXCAVATION
EXCEPTIONAL-VALUE WATERS
EXISTING CONDITIONS
EXTENDED DETENTION
FEMA
FILL
FILTER STRIP
FLOOD FRINGE
FLOODPLAIN
FLOODWAY
FOREST MANAGEMENT/TIMBER OPERATIONS
FREEBOARD
GOVERNING BODY
GRADE
(TO) GRADE
GRADING
GRASSED WATERWAY
GROUNDWATER RECHARGE
HIGH-QUALITY WATERS
HYDROGRAPH
HYDROLOGIC SOIL GROUP (HSG)
IMPERVIOUS SURFACE (IMPERVIOUS AREA)
IMPOUNDMENT
IMPROVEMENTS
INFILTRATION STRUCTURES
INLET
KARST
LAND DEVELOPMENT
(a)
(1)
(2)
(b)
(c)
LANDOWNER
LEVEL SPREADER
LICENSED PROFESSIONAL
LIMIT OF DISTURBANCE
MANNING'S EQUATION (MANNING'S FORMULA)
MAYOR
MINIMUM SEPARATION
MUNICIPALITY
NATIONAL POLLUTANT DISCHARGE ELIMINATION SYSTEM (NPDES)
NATURAL DRAINAGE FLOW
NOAA ATLAS 14
NON-POINT-SOURCE POLLUTION
NPDES PERMIT FOR STORMWATER DISCHARGES ASSOCIATED WITH CONSTRUCTION
ACTIVITIES
NRCS
ON-SITE STORMWATER MANAGEMENT
OPEN CHANNEL
OUTFALL
OUTLET
PADEP (or DEP)
PARENT TRACT
PARKING LOT STORAGE
PEAK DISCHARGE
PENNDOT
PENNSYLVANIA MUNICIPALITIES PLANNING CODE
PERSON
PERVIOUS AREA
PIPE
POINT SOURCE
POLLUTANT
POLLUTION
PROJECT SITE
QUALIFIED PROFESSIONAL
RATIONAL FORMULA
RECHARGE VOLUME
REDEVELOPMENT
REGULATED ACTIVITIES
(a)
(b)
(c)
(d)
(e)
(f)
(g)
(h)
(i)
(j)
(k)
REGULATED EARTH DISTURBANCE ACTIVITY
RELEASE RATE
RETENTION BASIN
RETENTION VOLUME/REMOVED RUNOFF
RETURN PERIOD
RIPARIAN BUFFER
RISER
ROOFTOP DETENTION
RUNOFF
RUNOFF CAPTURE VOLUME
SEDIMENT
SEDIMENT BASIN
SEDIMENT POLLUTION
SEDIMENTATION
SEEPAGE PIT/SEEPAGE TRENCH
SEPARATE STORM SEWER SYSTEM
SHALLOW CONCENTRATED FLOW
SHEET FLOW
SITE IMPROVEMENTS
SLOPE
SOIL COVER COMPLEX METHOD
SOIL STABILIZATION
SPILLWAY (EMERGENCY)
STABILIZATION
STATE WATER QUALITY REQUIREMENTS
(a)
(b)
(c)
(d)
STORAGE INDICATION METHOD
STORM FREQUENCY
STORM SEWER
STORMWATER
STORMWATER DETENTION
STORMWATER DETENTION BASIN
STORMWATER MANAGEMENT (SWM) SITE PLAN
STORMWATER MANAGEMENT
STORMWATER MANAGEMENT DISTRICT
STORMWATER MANAGEMENT FACILITIES (SWM BMPs)
STORMWATER MANAGEMENT PLAN
STREAM
STREAM BANK STABILIZATION
STREAM ENCLOSURE
SUBDIVISION
SUBWATERSHED AREA
SURFACE WATERS
SWALE
TIME OF CONCENTRATION (Tc)
TOPOGRAPHY
TOPSOIL
UNDEVELOPED LAND
USDA
VEGETATIVE COVER
WATER POLLUTION
WATER QUALITY VOLUME
WATER TABLE
WATERCOURSE
WATERS OF THE COMMONWEALTH
WATERSHED
WETLAND
Word list. As used
in this article, the following terms shall have the meanings indicated:
The removal of the surface of the land through the combined
action of man's activities and the natural process at a rate
greater than would occur because of the natural process alone.
Activities associated with agriculture, such as agriculture
cultivation, agriculture operation, and animal heavy-use areas. This
includes the work of producing crops, including tillage, land clearing,
plowing, disking, harrowing, planting, harvesting crops or pasturing
and raising of livestock and installation of conservation measures.
Construction of new buildings or impervious area is not considered
an agricultural activity.
As applied to land, a change in topography as a result of
the moving of soil and rock from one location or position to another;
the changing of surface conditions by causing the surface to be more
or less impervious; land disturbance.
A landowner, developer, their heirs, successors or assigns
or other person who has filed an application for approval to engage
in any regulated activities at a project site within the City of Lebanon.
Guides, grids, grating or similar devices placed in a pond
to deflect or regulate flow and create a longer flow path.
The flood, also known as the "one-hundred-year flood," which
has a one-percent chance of being equaled or exceeded in any given
year; the flood which has been selected to serve as the basis upon
which the floodplain management provisions of this article and other
ordinances have been prepared.
Activities, facilities, measures, planning 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. 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 wet 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.
A water quality practice that utilizes landscaping and soils
to treat stormwater runoff by collecting it in shallow depressions
before filtering through a fabricated planting soil media.
The Pennsylvania Stormwater Best Management Practices Manual
as published by the Department of Environmental Protection, Bureau
of Watershed Management, Document Number: 363-0300-002, effective
date: December 30, 2006, and as revised.
For the purpose of this article, a stormwater conveyance
structure requiring an effective span or diameter exceeding six feet.
Limestone or dolomite bedrock, also marble (within graphitic
felsic gneiss fm).
An earthen, stone or log structure, used in grass swales
to reduce water velocities, promote sediment deposition, and enhance
infiltration.
The City of Lebanon, Pennsylvania.
The governing body of the City of Lebanon. The legislative
powers of the City are vested in the City Council except as provided
in the City of Lebanon's Home Rule Charter.
The Commonwealth of Pennsylvania.
The Lebanon County Conservation District (LCCD). The Lebanon
County Conservation District has the authority under a delegation
agreement executed with the Pennsylvania Department of Environmental
Protection to administer all or a portion of the erosion and sediment
control program and construction activities within the political boundaries
of Lebanon County, Pennsylvania, including the City of Lebanon.
Includes the building, reconstruction, extension, expansion,
alteration, substantial improvement, or erection or relocation of
a building or structure, including manufactured homes, and gas or
liquid storage tanks. For floodplain purposes, "new construction"
includes structures for which the "start of construction" commenced
on or after the effective date of a floodplain management regulation
adopted by the municipality.
The ability of a pipe, culvert, swale or other similar facility
to carry the peak flow from the design storm.
Lebanon County, Pennsylvania.
A structure, with appurtenant works, that carries a stream
and/or stormwater runoff under or through an embankment or fill.
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.
The Pennsylvania Department of Environmental Protection.
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."
An impoundment structure designed to manage stormwater runoff
by temporarily storing the runoff and releasing it at a predetermined
rate.
A vegetated pond designed to collect water runoff for a given
storm event and release it at a predetermined rate; also known as
a "dry pond."
The volume of runoff that is captured and released during
or after a storm event and released into the waters of the commonwealth
at a controlled rate.
A person, partnership, association, corporation, or other
entity, or any responsible person therein or agent thereof, that undertakes
any regulated activity of this article.
Any man-made change to improved or unimproved real estate,
including but not limited to buildings or other structures, filling,
grading, paving, excavating, earth disturbance activity, mining, dredging
or drilling operations, the placement of manufactured homes, streets
and other paving, utilities, and the subdivision of land.
An unstabilized land area where an earth disturbance activity
is occurring or has occurred.
That portion of the property line of the lot, tract, or parcels
of land being developed located such that overland or piped flow from
the site would be directed toward it.
A stormwater management facility designed to convey stormwater
runoff, and shall include streams, channels, swales, pipes, conduits,
culverts, storm sewers, etc.
A right granted by a landowner to a grantee, allowing the
use of private land for stormwater management, drainage, or conveyance
purposes.
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, mineral extraction,
and the moving, depositing, stockpiling, or storing of soil, rock
or earth materials.
A device used to slow the velocity of stormwater, particularly
at points of concentrated discharge, such as pipe outlets.
A registered engineer designated by the Mayor to perform
duties as required by this article on behalf of the City.
The natural process by which the surface of the land is worn
away by water, wind or chemical action.
A site-specific plan consisting of both drawings and narrative
that identifies BMPs that minimize accelerated erosion and sedimentation
before, during and after earth disturbance activities.
Any act by which earth, sand, gravel, rock or any other similar
material is dug into, cut, quarried, uncovered, removed, displaced,
relocated or bulldozed. It shall include the conditions resulting
therefrom.
Surface waters of high quality, which satisfies Pa. Code,
Title 25, Environmental Protection, Chapter 93, Water Quality Standards,
§ 93.4b(b) (relating to antidegradation).
All existing pervious land cover shall be considered as "meadow"
unless the natural land cover is documented to generate lower curve
numbers or Rational "C" coefficients, such as forested lands.
A stormwater design feature that provides for the gradual
release of a volume of water in order to increase settling of pollutants
and protect downstream channels from frequent storm events.
The Federal Emergency Management Agency.
Any act by which earth, sand, gravel, rock or any other material
is placed, pushed, dumped, pulled, transported or moved to a new location
above the natural surface of the ground or on top of the stripped
surface, and shall include the conditions resulting therefrom; the
difference in elevation between a point on the original ground and
a designated point of higher elevation on the final grade; the material
used to make fill.
A strip of permanent vegetation above ponds, diversions and
other structures to retard the flow of runoff, causing deposition
of transported material, thereby reducing sedimentation.
The remaining portions of the one-hundred-year floodplain
outside of the floodway boundary.
Any land 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).
The channel of 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.
Planning and activities necessary for the management of forest
land. 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.
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.
The Mayor and five Councilors together make up the governing
body of the City of Lebanon. The Mayor is the Chief Executive of the
City and enforces the ordinances of Council.
A reference plane, usually of the road, channel or natural
ground, specified in percent and shown on plans as specified herein.
To finish surface of a roadbed, top of embankment or bottom
of excavation.
The act of moving earth; changing of the earth surface by
excavation or fill.
A natural or constructed waterway, usually broad and shallow,
covered with erosion-resistant grasses, often used to conduct surface
water from cropland.
Replenishment of existing natural underground water supplies.
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 Pa. Code, Title 25, Environmental
Protection, Chapter 93, Water Quality Standards, § 93.4b(a).
A graph showing the rate of flow (discharge) versus time
past a specific point in a river or other channel or conduit carrying
flow, or to a point of interest. The rate of flow is typically expressed
in cubic meters or cubic feet per second (cms or cfs).
A classification of soils by the Natural Resources Conservation
Service into one of four HSG classifications (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 (USDA) 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 generated by the use of
the NRCS Web Soil Survey at http://websoilsurvey.nrcs.usda.gov. Soils
become less pervious as the HSG varies from A to D.
A surface that prevents the infiltration of water into the
ground. Impervious surfaces (or areas) shall include, but are not
limited to: roofs, additional indoor living spaces, patios, garages,
storage sheds and similar structures, streets, driveways, sidewalks,
and vehicle and pedestrian areas that are gravel and crushed stone.
Any surface area proposed to initially be gravel, crushed stone or
paving shall be assumed to be impervious. Pervious paving shall be
considered as an impervious surface for runoff management and storage
calculations. In addition, other areas determined by the City Engineer
to be impervious within the meaning of this definition shall also
be considered as contributing to total impervious cover.
A retention or detention basin designed to retain stormwater
runoff and release it at a controlled rate.
Physical additions and changes to the land, necessary to
produce usable and desirable lots.
A structure designed to direct runoff into the ground (e.g.,
French drains, seepage pits, seepage trench, bioinfiltration facilities,
etc.).
A surface connection to a closed drain; a structure at the
diversion of a conduit; the upstream end of any structure through
which water may flow.
A type of topography or landscape characterized by surface
depressions, sinkholes, rock pinnacles/uneven bedrock surface, steep-sided
hills, underground drainage and caves. Karst is formed on carbonate
rocks, such as limestone, dolomites, marble and sometimes gypsum.
Any of the following activities:
The improvement of one lot or two or more contiguous lots, tracts
or parcels of land for any purpose involving:
A group of two or more residential or nonresidential buildings,
whether proposed initially or cumulatively, or a single nonresidential
building on a lot or lots regardless of the number of occupants or
tenure; or
The division or allocation of land or space, whether initially
or cumulatively, between or among two or more existing or prospective
occupants by means of, or for the purpose of, streets, common areas,
leaseholds, condominiums, building groups or other features.
Any subdivision of land.
Development in accordance with Section 503(1.1) of the Pennsylvania
Municipalities Planning Code.[1]
The legal or beneficial owner or owners of land, including
the holder of an option or contract to purchase (whether or not such
option or contract is subject to any condition), a lessee if he is
authorized under the lease to exercise the rights of the landowner,
or other person having a proprietary interest in land.
A level structural device providing a smooth, stable surface,
such as concrete or similar nondegradable material, which effectively
distributes stormwater uniformly over the ground surface as sheet
flow to prevent concentrated, erosive flows and promote infiltration.
Professional engineers, landscape architects, geologists
and land surveyors licensed to practice within the Commonwealth of
Pennsylvania.
A line provided on the erosion and sediment control and stormwater
management site plan that indicates the total area to be disturbed
during a proposed earth disturbance activity.
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.
The Chief Executive and Administrative Officer of the City
and the official head of the Lebanon City government who enforces
the ordinances of City Council.
The minimum distance between the discharge or runoff from
impervious surfaces and the receiving stream, storm sewer or property
line, whichever is smaller, whether the discharge is point or nonpoint
discharge. It is intended to provide ample, natural, undisturbed,
vegetated, pervious areas to allow for the infiltration of increased
volumes of runoff.
The City of Lebanon, Lebanon County, Pennsylvania.
The national system for the issuance of permits under Section
402 of the Federal Clean Water Act (33 U.S.C. § 1342), including
a state or interstate program which has been approved in whole or
in part by the Environmental Protection Agency, including the regulations
codified in Chapter 92 (relating to NPDES permitting, monitoring and
compliance), and as specified in Title 25, Chapter 102.
The pattern of surface and stormwater drainage from a particular
site before construction or installation of improvements or prior
to any regrading.
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 Study Center, Silver Spring, Maryland (2004). NOAA's Atlas
14 can be accessed at Internet address: http://hdsc.nws.noaa.gov/hdsc/pfds/.
Pollution that enters a water body from diffuse origins in
the watershed and does not result from discernible, confined, or discrete
conveyances.
A permit required for the discharge or potential discharge
of stormwater into waters of the commonwealth from construction activities,
including clearing and grubbing, grading and excavation activities
involving one acre or more of earth disturbance activity or an earth
disturbance activity on any portion, part, or during any stage of
a larger common plan of development or sale that involves one acre
or more of earth disturbance activity over the life of the project.
The Natural Resources Conservation Service [previously Soil
Conservation Service (SCS)].
The control of runoff to allow water falling on a given site
to be absorbed or retained on site to the extent that, after development,
the peak rate of discharge leaving the site does not exceed the allowable
rate as directed by this article.
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.
Points of water disposal from a stormwater conveyance system,
stream, river, lake, tidewater or artificial drain.
The Pennsylvania Department of Environmental Protection.
All contiguous land held in single and separate ownership,
regardless whether: (a) such land is divided into one or more lots,
parcels, purports or tracts; (b) such land was acquired by the landowner
at different times or by different deeds, devise, partition or otherwise;
or (c) such land is bisected by public or private streets or rights-of-way,
which was held by the landowner or his predecessor in title on the
effective date of this article.
Involves the use of impervious or semi-impervious parking
areas as temporary impounds with controlled release rates during rainstorms.
The maximum rate of stormwater runoff from a specific storm
event.
The Pennsylvania Department of Transportation.
Adopted as Act 247 of 1968, this act enables municipalities
to plan for and regulate community development with subdivision and
land development ordinances. The code also contains guidelines for
subdivision and land development ordinance content. For the purpose
of this article, the code is referred to as "Act 247" and is intended
to include the current code and any further amendments thereto.[2]
An individual, partnership, public or private association
or corporation, or a governmental unit, public utility or any other
legal entity whatsoever which is recognized by law as the subject
of rights and duties.
Any area not defined as impervious.
A culvert, closed conduit, or similar structure (including
appurtenances) that conveys stormwater.
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 Pa. Code, Title 25, § 92.1.
Any contaminant or other alteration of the physical, chemical,
biological or radiological integrity of surface water which causes
or has the potential to cause pollution as defined in Section 1 of
the Clean Streams Law (35 P.S. §§ 691.1-691.1001).
Contamination of any surface waters such as will create or
is likely to create a nuisance or render such waters harmful, detrimental
or injurious to public health, safety or welfare, or to domestic,
municipal, commercial, industrial, agricultural, recreational, or
other legitimate beneficial uses, or to livestock, wild animals, birds,
fish or other aquatic life, including but not limited to such contamination
by alteration of the physical, chemical or biological properties of
such waters or change in temperature, taste, color or odor thereof,
or the discharge of any liquid, gaseous, radioactive, solid or other
substances into such waters.
The specific area of land where any regulated activities
are planned, conducted, or maintained.
Any person licensed by the Pennsylvania Department of State
or otherwise qualified by law to perform the work required by this
article.
A rainfall-runoff relation used to estimate peak flow.
The portion of the water quality volume used to maintain
groundwater recharge rates at development sites.
Earth disturbance activities on land which has previously
been developed.
Any earth disturbance activities or any activities that involve
the alteration or development of land in a manner that may affect
stormwater runoff and activities that may contribute nonstormwater
runoff discharges to a regulated small MS4. "Regulated activities"
include, but are not limited to, the following listed items:
Earth disturbance activities.
Land development.
Subdivision.
Construction of new or additional impervious or semi-impervious
surfaces.
Construction of new buildings or additions to existing buildings.
Diversion or piping of any natural or man-made stream channel.
Installation of new or modification of existing stormwater management
facilities or appurtenances thereto.
Installation of new or modification of existing stormwater BMPs.
Changes in soil absorption caused by compaction during development
or timber harvesting.
Redirection or concentration of runoff to adjoining properties,
as it relates to properties regulated under this article.
Modification in contours, including filling and/or draining
of low areas, as it relates to properties regulated under this article.
Activity involving earth disturbance subject to regulation
under Pa. Code, Title 25, Chapter 92, 25 Pa. Code Chapter 102, or
the Clean Streams Law.
The percentage, or event criteria, of the 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.
A pond containing a permanent pool of water designed and/or
constructed to store water runoff for a given storm event and release
it at a predetermined rate.
The volume of runoff that is captured and not released directly
into the surface waters of the commonwealth during or after a storm
event.
The average interval, in years, within which a storm event
of a given magnitude can be expected to recur. For example, the probability
of a twenty-five-year storm occurring in any one given year is 0.04
(i.e., a four-percent chance).
A permanent vegetated area bordering surface waters, that
serves as a protective filter to help protect streams and wetlands
from impacts of adjacent land uses.
A vertical structure extending from the bottom of a pond
that is used to control the discharge rate from the pond for a specified
design storm.
Temporary ponding and gradual release of stormwater falling
directly onto flat roof surfaces by incorporating controlled-flow
roof drains into building designs.
Any part of precipitation that flows over the land surface.
The volume of runoff that is captured (retained) and not
released into surface waters of the commonwealth during or after a
storm event.
Soils or other erodible materials transported by stormwater
as a product of erosion.
An impoundment being used to remove sediment from stormwater
runoff.
The placement, discharge or any other introduction of sediment
into the waters of the commonwealth occurring from the failure to
design, construct, implement, or maintain control measures and control
facilities in accordance with the requirements of this article.
The process by which mineral or organic matter is accumulated
or deposited by the movement of air or water.
An area of excavated earth filled with loose stone or similar
course material, into which water is directed for infiltration into
the ground.
A conveyance or system of conveyances (including roads with
drainage systems, municipal streets, catch basins, curbs, gutters,
ditches, man-made channels, or storm drains) primarily used for collecting
and conveying stormwater runoff.
Runoff pattern following sheet flow, prior to open channel
flow.
Runoff flow that occurs over land in places where there are
no defined channels; the floodwater spreads out over a large area
at a uniform depth. This also referred to as "overland flow."
Physical additions or changes to the land that may be necessary
to provide usable and desirable lots, including, but not limited to,
utilities, streets, curbing, sidewalks, streetlights and stormwater
facilities.
Deviation of any surface from horizontal. For engineering
purposes, slopes are usually expressed in a percentage based upon
vertical difference in feet per 100 feet of horizontal distance.
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)."
The chemical or structural treatment of a mass of soil to
increase or maintain its stability or otherwise to improve its engineering
properties.
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.
The proper placing, grading, constructing, reinforcing, lining
and covering of soil, rock or earth to ensure its resistance to erosion,
sliding or other movement.
The regulatory requirements to protect, maintain, reclaim,
and restore water quality under Title 25 of the Pennsylvania Code
and the Clean Streams Law, including, but not limited to:
Each stream segment in Pennsylvania has a "designated use,"
such as "cold water fishery" or "potable water supply," which is listed
in Chapter 93. These uses must be protected and maintained, under
state regulations.
"Existing uses" are those attained as of November 1975, regardless
whether they have been designated in Chapter 93. Earth disturbance
activities 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.
Water quality involves the chemical, biological, and physical
characteristics of surface water bodies. After earth disturbance activities
are complete, these characteristics can be impacted by addition of
pollutants such as sediment, and changes in habitat through increased
flow volumes and/or rates as a result of changes in land surface area
from those activities. Therefore, permanent discharges to surface
waters must be managed to protect the stream bank, streambed, and
structural integrity of the waterway, to prevent these impacts.
Protection and maintenance of water quality in special-protection
streams pursuant to Pa. Code, Title 25, Chapter 93.
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.
The number of times that a given storm "event" occurs or
is exceeded on the average in a stated period of years.
A system of pipes and/or open channels that convey intercepted
runoff and stormwater from other sources, but excludes domestic sewage
and industrial wastes.
Drainage runoff from the surface of the land resulting from
precipitation or snow or ice melt.
Any storm drainage technique that retards or detains runoff,
such as detention or retention basins, parking lot storage, rooftop
storage, porous pavement, dry wells or any combination thereof.
A vegetated pond designed to drain completely after storing
runoff only for a given storm event and release it at a predetermined
rate; also known as a "dry pond."
The plan prepared by a qualified professional indicating
how stormwater runoff will be managed at the project site according
to this article.
The control of runoff to allow water falling on a given site
to be absorbed or retained on site to the extent that, after development,
the peak-rate discharge leaving the site does not exceed the allowable
rate based on conditions prior to development.
A watershed or subwatershed area for which separate stormwater
management regulations or criteria have been established.
A system designed to handle stormwater runoff and, where
required, delay the peak discharge long enough to minimize the potential
for downstream flooding; 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 basins, wet
ponds, open channels, storm sewers, pipes and infiltration facilities.
A plan for managing stormwater runoff on a watershed-wide
basis, as required by the Act of October 4, 1978, P.L. 864 (Act 167),
as amended, and known as the "Storm Water Management Act."
A watercourse; a channel or conveyance of surface water having
defined bed and banks, whether natural or artificial, with perennial
or intermittent flow.
A collection of vegetative and/or mechanical means for stabilizing
stream banks to minimize, prevent or abate degradation.
A bridge, culvert, or other structure in excess of 100 feet
in length upstream to downstream, which encloses regulated waters
of the commonwealth.
The division or redivision of a lot, tract or parcel of land
by any means into two or more lots, tracts, parcels or other divisions
of land, including changes in existing lot lines, for the purpose,
whether immediate or future, of lease, partition of the court for
distribution to heirs or devisees, transfer of ownership or building
or lot development; provided, however, that the subdivision by lease
of land for agricultural purposes into parcels of more than 10 acres,
not involving any new street or easement of access, or any residential
dwelling, shall be exempted.
The smallest drainage unit of a watershed for which stormwater
management criteria has been established.
Perennial and intermittent streams, rivers, lakes, reservoirs,
ponds, wetlands, springs, natural seeps and estuaries, excluding water
in facilities approved for wastewater treatment, such as wastewater
treatment impoundments, cooling water ponds and constructed wetlands
used as part of a wastewater treatment process.
A low-lying stretch of land that gathers or carries surface
water runoff; a watercourse without defined bed and bank.
The time for surface water 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.
A general term that includes the characteristics of the ground
surface, such as hills, plains, mountains, degree of relief, steepness
of slope and physiographic features; the configuration of a surface
area showing relative elevations.
Acceptable friable loam that is free of subsoil, clay lumps,
brush, roots, weeds, other objectionable vegetation, stones, other
foreign material larger than two inches in any dimension, litter,
and/or other material unsuitable or harmful to plant growth.
Any lot which has not been graded or in any other manner
prepared for the construction of a building.
The United States Department of Agriculture.
Such cover shall consist of trees, shrubs, flowers, grass
or similar natural cover.
The addition of pollutants to water in concentrations or
in sufficient quantities to result in measurable degradation of water
quality.
The total volume of water runoff that is required to be collected
and treated for water quality control by direction to BMP facilities.
The upper surface of groundwater, or that level below which
the soil is seasonally saturated with water.
A channel or conveyance of surface water, having defined
bed and banks, whether natural or artificial, with perennial or intermittent
flow.
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.
A region or area drained by a river, watercourse, or other
surface water, whether natural or artificial; also synonymous with
"subwatershed" and "drainage area" referring to local drainage area
of interest for site-specific calculations.
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 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, the Pennsylvania
Coastal Zone Management Plan and a wetland area designated by a river
basin commission. Wetlands include all lands regulated as wetlands
by the Pennsylvania Department of Environmental Protection or the
United States Army Corps of Engineers. In the event there is a conflict
between the definitions of these agencies, the more-restrictive definition
applies).
