These definitions do not necessarily reflect the definitions contained
in pertinent regulations or statutes and are intended for this chapter
only.
ACCELERATED EROSION
The removal of the surface of the land through the combined
action of human activities and natural processes, at a rate greater
than would occur because of the natural process alone.
AGRICULTURAL ACTIVITY
Activities associated with agriculture such as agricultural
cultivation, agricultural operation, and animal heavy use areas. This
includes the work of producing crops, including tillage, land clearing,
plowing, disking, harrowing, planting, harvesting crops or pasturing
and raising of livestock and installation of conservation measures.
Construction of new buildings or impervious area is not considered
an agricultural activity.
AGRICULTURAL PLOWING OR TILLING ACTIVITY
(1)
Earth disturbance activity involving the preparation and maintenance
of soil for the production of agricultural crops.
(2)
The term includes no-till cropping methods, the practice of
planting crops with minimal mechanical tillage.
APPLICANT
A landowner, developer, person, partnership, association,
corporation or other entity or other responsible person therein or
agent thereof, who has filed an application to the Township for approval
to engage in any regulated activity at a project site in the Township.
BEST MANAGEMENT PRACTICE (BMP)
Activities, facilities, designs, measures, or procedures used to manage stormwater quantity and quality impacts from regulated activities listed in §
296-5 to meet state water quality requirements, to promote groundwater recharge, and to otherwise meet the purposes of this chapter. Stormwater BMPs are commonly grouped into one of two broad categories or measures: "structural" or "nonstructural." In this chapter, nonstructural BMPs or measures refer to operational and/or behavior-related practices that attempt to minimize the contact of pollutants with stormwater runoff, whereas structural BMPs or measures are those that consist of a physical device or practice that is installed to capture and treat stormwater runoff. Structural BMPs include, but are not limited to, a wide variety of practices and devices, from large-scale retention ponds and constructed wetlands to small-scale underground treatment systems, infiltration facilities, filter strips, low impact design, bioretention, wet ponds, permeable paving, grassed swales, riparian or forested buffers, sand filters, detention basins, and manufactured devices. Structural stormwater BMPs are permanent appurtenances to the project site.
BIORETENTION
Densely vegetated, depressed features that store stormwater
and filter it through vegetation, mulch, planting soil, etc. Ultimately
stormwater is evapotranspirated, infiltrated or discharged. Optimal
bioretention areas mimic natural forest ecosystems in terms of species
diversity, density, distribution, use of native plants, etc.
BUFFER
(1)
Streamside buffer. A zone of variable width located along a
stream that is vegetated and is designed to filer pollutants from
runoff.
(2)
Special geologic feature buffer. A required isolation distance
from a special geologic feature to a proposed BMP needed to reduce
the risk of sinkhole formation due to stormwater management activities.
CAPTURE/REUSE
Stormwater management techniques, such as cisterns and rain
barrels which direct runoff into storage devices, surface or subsurface
for later reuse, such as irrigation of gardens and other planted areas.
CARBONATE BEDROCK
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.
CISTERN
An underground reservoir or tank for storing rainwater.
CLOSED DEPRESSION
In a karst area, a distinctive bowl-shaped depression in
the land surface. It is characterized by internal drainage, varying
magnitude, and an unbroken ground surface.
CONSTRUCTED WETLANDS
Constructed wetlands are similar to wet ponds (see below)
and consist of a basin which provides for necessary stormwater storage
as well as a permanent pool or water level, planted with wetland vegetation.
To be successful, constructed wetlands must have adequate natural
hydrology (both runoff inputs as well as soils and water table which
allow for maintenance of a permanent pool of water). In these cases,
the permanent pool must be designed carefully, usually with shallow
edge benches, so that water levels are appropriate to support carefully
selected wetland vegetation.
CULVERT
A pipe, conduit or similar structure including appurtenant
works which carries surface water.
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 semi fluid.
DEP
The Pennsylvania Department of Environmental Protection.
DESIGN STORM
The depth and time distribution of precipitation from a storm
event measured in probability of occurrence (e.g., 100-year storm)
and duration (e.g., 24 hours), used in the design and evaluation of
stormwater management control systems.
DETENTION BASIN
A basin designed to retard 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 the
waters of the commonwealth at a controlled rate.
DIRECT RECHARGE/SUBSURFACE BMP
A BMP designed to direct runoff to groundwater recharge without
providing for vegetative uptake. Examples include infiltration trenches,
seepage beds, drywells, and stormwater drainage wells such that nearly
all runoff becomes recharge to groundwater.
DISTURBED AREA
An unstabilized land area where an earth disturbance activity
is occurring or has occurred.
DRAINAGE EASEMENT
A right granted by a landowner to a grantee, allowing the
use of private land for stormwater management purposes.
DRAINAGE PLAN
The documentation of the proposed stormwater quantity and quality management controls, if any, to be used for a given development site, including a BMP operations and maintenance plan, the contents of which are established in §
296-21.
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.
EROSION
The natural process by which the surface of the land is worn
away by water, wind, ice, chemical action or other geological agents.
EXISTING CONDITION
The dominant land cover during the five-year period immediately
preceding a proposed regulated activity.
EXISTING USES
Those uses actual attained in the water body on or after
November 28, 1975, whether or not they are included in the water quality
standards. (25 Pa. Code Chapter 93.1)
FEMA
Federal Emergency Management Agency.
FILL
Man-made deposits of natural soils or rock products and waste
materials.
FLOODPLAIN
Any land area susceptible to inundation by water from any
natural source or delineated by applicable FEMA maps and studies as
being a special flood hazard area. Also includes areas that comprise
Group 13 Soils, as listed in Appendix A of the Pennsylvania DEP Technical
Manual for Sewage Enforcement Officers (as amended or replaced from
time to time by DEP).
FLOODWAY
The channel of the watercourse and those portions of the
adjoining floodplains that are reasonably required to carry and discharge
the 100-year flood. Unless otherwise specified, the boundary of the
floodway is as indicated on maps and flood insurance studies provided
by FEMA. In an area where no FEMA maps or studies have defined the
boundary of the 100-year floodway, it is assumed - absent evidence
to the contrary - that the floodway extends from the stream to 50
feet from the top of the bank of the stream.
FOREST MANAGEMENT/TIMBER OPERATIONS
Planning and activities necessary for the management of forestland.
These include conducting a timber inventory, preparation of forest
management plans, silvicultural treatment, cutting budgets, logging
road design and construction, timber harvesting, site preparation,
and reforestation.
FREEBOARD
The incremental depth in a stormwater management structure,
provided as a safety factor of design, above that required to convey
the design runoff event.
GREEN INFRASTRUCTURE
Systems and practices that use or mimic natural processes
to infiltrate, evapotranspire, or reuse stormwater on the site where
it is generated.
HARDSHIP WAIVER REQUEST
A written request for a waiver alleging that the provisions
of this chapter inflict unnecessary hardship upon the applicant. Hardship
waiver does not apply to and is not available from the water quality
provisions of this chapter shall not be granted.
HOT SPOT LAND USES
A land use or activity that generates higher concentrations of hydrocarbons, trace metals or other toxic substances than typically found in stormwater runoff. These land uses are listed in §
296-15P.
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 HSGs (A, B, C and D) to indicate the minimum
infiltration rates, which are obtained for bare soil after prolonged
wetting. The Natural Resources Conservation Service (NRCS) defines
the four groups and provides a list of most of the soils in the United
States and their group classification. The soils in the area of the
development site may be identified from a soil survey report that
can be obtained from local NRCS offices or conservation district offices.
Soils become less previous as the HSG varies from A to D (NRCS).
IMPERVIOUS SURFACE (IMPERVIOUS COVER)
A surface which prevents the percolation of water into the
ground. Impervious surfaces (or areas) shall include, but not be limited
to: roofs; additional indoor living spaces, swimming pools, patios,
garages, storage sheds and similar structures; and any new streets
or sidewalks. Decks, parking areas, and driveway areas are not counted
as impervious areas if they do not prevent infiltration.
INFILTRATION PRACTICE
A practice designed to allow direct runoff an opportunity
to infiltrate into the ground (e.g., French drain, seepage pit, seepage
trench or bioretention area).
INFILTRATION STRUCTURE
A structure designed to direct runoff into the ground (e.g.,
French drain, seepage pit or seepage trench).
KARST
A type of topography or landscape characterized by surface
depressions, sinkholes, rock pinnacles/uneven bedrock surface, underground
drainage and caves. Karst is usually formed on carbonate rocks, such
as limestones or dolomites.
LAND DEVELOPMENT
Inclusive of any or all of the following meanings:
(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, 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.
(d)
Development in accordance with § 503(1.1) of the Pennsylvania
Municipalities Planning Code.
LOADING RATE
The ratio of the land area draining to the system, as modified by the weighting factors in §
296-18B compared to the base area of the infiltration system.
LOW IMPACT DEVELOPMENT (LID)
Site design approaches and small-scale stormwater management
practices that promote the use of natural systems for infiltration,
evapotranspiration, and reuse of rainwater. LID can be applied to
new development, urban retrofits, and revitalization projects. LID
utilizes design techniques that infiltrate, filter, evaporate, and
store runoff close to its source. Rather than rely on costly large-scale
conveyance and treatment systems, LID addresses stormwater through
a variety of small, cost-effective landscape features located on-site.
MAINSTEM (MAIN CHANNEL)
Any stream segment or other conveyance used as a reach in
the Little Lehigh Creek and Jordan Creek hydrologic models. In the
Coplay Creek watershed, any stream segment or other conveyance in
a dual release rate or conditional no detention I subarea used as
a reach in the hydrologic model. In conditional no detention II subareas
the main channel is the Lehigh River.
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.
MARYLAND STORMWATER DESIGN MANUAL
A stormwater design manual written by the Maryland Department
of the Environment and the Center for Watershed Protection. The manual
can be obtained through the following web site: www.mde.state.md.us.
MINIMUM DISTURBANCE/MINIMUM MAINTENANCE PRACTICES (MD/MM)
A site design practice in which careful limits are placed
on site clearance prior to development allowing for maximum retention
of existing vegetation (woodlands and other), minimum disturbance
and compaction of existing soil mantle and minimum site application
of chemicals post-development. Typically, MD/MM includes disturbance
setback criteria from buildings as well as related site improvements
such as walkways, driveways, roadways and any other improvements.
These criteria may vary by community context as well as by type of
development being proposed. Additionally, MD/MM also shall include
provisions (e.g., deed restrictions, conservation easements) to protect
these areas from future disturbance and from application of fertilizers,
pesticides and herbicides.
NO HARM RUNOFF QUANTITY OPTION
The option of using a less restrictive runoff quantity control
if it can be shown that adequate and safe runoff conveyance exists
and that the less restrictive control would not adversely affect health,
safety and property.
NRCS
USDA Natural Resource Conservation Service (formerly the
Soil Conservation Service).
OIL/WATER SEPARATOR
A structural mechanism designed to remove free oil and grease
(and possibly solids) from stormwater runoff.
OUTFALL
"Point source" as described in 40 CFR § 122.2 at
the point where the Township's storm sewer system discharges
to waters of the commonwealth.
OWNER
One with an interest in and often dominion over a property.
PEAK DISCHARGE
The maximum rate of flow of stormwater runoff at a given
location and time resulting from a specific storm event.
PENN STATE RUNOFF MODEL (PSRM)
The computer-based hydrologic modeling technique adapted
to each watershed for the Act 167 Plans. The model was calibrated
to reflect actual flow values by adjusting key model input parameters.
PERSON
An individual, partnership, public or private association
or corporation, or a governmental unit, public utility or other for
or not for profit statutory entity or other legal entity whatsoever
which is recognized by law as the subject of rights and duties.
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.
PRE-TREATMENT
Measures implemented for hot spot land uses designed to reduce
concentration of hydrocarbons, trace metals, and other toxic substances
to levels typically found in stormwater runoff.
PRELIMINARY SITE INVESTIGATION
The determination of the depth to bedrock, the depth to the
seasonal high-water table and the soil permeability for a possible
infiltration location on a site through the use of published data
and on-site surveys. In carbonate bedrock areas, the location of special
geologic features must also be determined along with the associated
buffer distance to the possible infiltration area.
PROJECT SITE
The specific area of land where any regulated activities
in the Township are planned, conducted, or maintained.
PUBLIC WATER SYSTEM
A system which provides water to the public for human consumption
which has at least 15 service connections or regularly serves an average
of at least 25 individuals daily at least 60 days out of the year.
(See 25 Pa. Code Chapter 109.)
QUALIFIED PROFESSIONAL
Any person licensed by the Pennsylvania Department of State
or otherwise qualified by law to perform work required by this chapter.
RATIONAL METHOD
A method of peak runoff calculation using a standardized
runoff coefficient (rational 'c'), acreage of tract and
rainfall intensity determined by return period and by the time necessary
for the entire tract to contribute runoff. The rational formula is
stated as follows: Q = ciA, where "Q" is the calculated peak flow
rate in cubic feet per second, "c" is the dimensionless runoff coefficient
(see Appendix C), "i" is the rainfall intensity in inches per hour,
and "A" is the area of the tract in acres. The Rational method formula
for runoff volume calculation is as follows: V= cPA/12 where "c" and
"A" are as noted above, "P" is the total depth of precipitation for
the design event in inches, and "V" is the total runoff volume in
acre-feet.
REACH
Any of the natural or man-made runoff conveyance channels
used for watershed modeling purposes to connect the subareas and transport
flows downstream.
RECHARGE VOLUME (REv)
The portion of the water quality volume (WQv) used to maintain groundwater recharge rates at development sites. (See §
296-15J.)
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 and which are governed by this chapter as specified in §
296-5D.
REGULATED EARTH DISTURBANCE ACTIVITY
Activity involving earth disturbance, other than agricultural
plowing or tilling, subject to regulation under 25 Pa. Code 92, 25
Pa. Code 102, or the Clean Streams Law. Earth disturbance activity other than agricultural plowing
or tilling of one acre or more with a point source discharge to surface
waters or to the Township's storm sewer system or earth disturbance
activity of five acres or more regardless of the planned runoff. This
includes earth disturbance on any portion of, part or during any stage
of a larger common plan of development.
RELEASE RATE
The percentage of the pre-development peak rate of runoff
for a development site to which the post-development peak rate of
runoff must be controlled to avoid peak flow increases throughout
the watershed.
RETURN PERIOD
The average interval, in years, within which a storm event
of a given magnitude can be expected to occur one time. For example,
the twenty-five-year return period rainfall would be expected to occur
on average once every 25 years: or stated in another way, the probability
of a twenty-five-year storm occurring in any one year is 0.04 (i.e.,
a 4% chance).
RIPARIAN BUFFER
A permanent area of trees and shrubs located adjacent to
streams, lakes, ponds and wetlands.
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.
RUNOFF
That part of precipitation which flows over the land.
RUNOFF BMP
A BMP designed for essentially the full volume of runoff
entering the BMP to be discharged off-site.
SEDIMENT
Soils or other materials transported by surface water as
a product of erosion.
SEDIMENT TRAPS/CATCH BASIN SUMPS
A chamber which provides storage below the outlet in a storm
inlet to collect sediment, debris and associated pollutants, typically
requiring periodic clean out.
SEEPAGE PIT/SEEPAGE TRENCH
An area of excavated earth filled with loose stone or similar
material and 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
Stormwater runoff flowing in a thin layer over the ground
surface.
SOIL-COVER-COMPLEX METHOD
A method of runoff computation developed by NRCS which is
based upon relating soil type and land use/cover to a runoff parameter
called a curve number.
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.
SPILL PREVENTION AND RESPONSE PROGRAM
A program that identifies procedures for preventing and,
as needed, cleaning up potential spills and makes such procedures
known and the necessary equipment available to appropriate personnel.
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 including:
(1)
Each stream segment in Pennsylvania has a "designated use,"
such as "cold water fishes" or "potable water supply," which are listed
in Chapter 93. These uses must be protected and maintained, under
state regulations.
(2)
"Existing uses" are those attained as of November 1975, regardless
whether they have been designated in Chapter 93. Regulated 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.
(3)
Water quality involves the chemical, biological and physical
characteristics of surface water bodies. After regulated 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.
STORAGE INDICATION METHOD
A method of routing or moving an inflow hydrograph through
a reservoir or detention structure. The method solves the mass conservation
equation to determine an outflow hydrograph as it leaves the storage
facility.
STORM DRAINAGE PROBLEM AREAS
Areas which lack adequate stormwater collection and/or conveyance
facilities and which present a hazard to persons or property. These
areas are either documented in Appendix B of this chapter or identified
by the Township or Township Engineer.
STORM SEWER
A system of pipes or other conduits which carries intercepted
surface runoff, street water and other wash waters or drainage, but
excludes domestic sewage and industrial wastes.
STORMWATER
Drainage runoff from the surface of the land resulting from
precipitation or snow or ice melt.
STORMWATER DRAINAGE WELLS
Wells for injection of stormwater to the surface that are
regulated by the U.S. Environmental Protection Agency to protect underground
sources of drinking water.
STORMWATER FILTERS
Any number of structural mechanisms such as multi-chamber
catch basins, sand/peat filers, sand filters and so forth, which are
installed to intercept stormwater flow and remove pollutants prior
to discharge. Typically, these systems require periodic maintenance
and clean out.
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 limited
to: detention and retention basins; open channels; storm sewers; pipes;
and infiltration facilities.
STORMWATER MANAGEMENT PLAN
The plan for managing stormwater runoff adopted by Lehigh
County for the Little Lehigh Creek, Jordan Creek, and Coplay Creek
Watersheds 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 developer or his representative
indicating how stormwater runoff will be managed at the development
site in accordance with this chapter. Stormwater management site plan
will be designated as SWM site plan throughout this chapter.
SUBAREA
The smallest unit of watershed breakdown for hydrologic modeling
purposes for which the runoff control criteria have been established
in the stormwater management plan.
SUBDIVISION
As defined in the Pennsylvania Municipalities Planning Code,
Act of July 31, 1968, P.L. 805, No. 247. The division or redivision
of a lot, tract or parcel of land by any means into two or more lots,
tracts, parcels or other divisions of land including changes in existing
lot lines for the purpose, whether immediate or future, of lease,
partition by the court for distribution to heirs or devisees, transfer
or 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.
SURFACE WATERS
Perennial and intermittent streams, rivers, lakes, reservoirs,
ponds, wetlands, springs, natural seeps, and estuaries, excluding
water at facilities approved for wastewater treatment such as wastewater
treatment impoundments, cooling water ponds and constructed wetlands
used as part of a wastewater process.
SWALE
A low-lying stretch of land which gathers or carries surface
water runoff. See also "vegetated swale."
TIMBER HARVESTING ACTIVITIES
Earth disturbance activities, including the construction
of skid trails, logging roads, landing areas and other similar logging
or silvicultural practices.
TOWNSHIP
South Whitehall Township, Lehigh County, Pennsylvania.
TRASH/DEBRIS COLLECTORS
Racks, screens or other similar devices installed in a storm
drainage system to capture coarse pollutants (trash, leaves, etc.).
USDA
United States Department of Agriculture.
VEGETATED BUFFERS
Gently sloping areas that convey stormwater as sheet flow
over a broad, densely vegetated earthen area, possibly coupled with
the use of level spreading devices. A water quality BMPs, vegetated
buffers serve to filter pollutants from runoff and promote infiltration.
Vegetated buffers should be situated on minimally disturbed soils,
have low-flow velocities and extended residence times. Vegetated buffers
may be, but are not restricted to, use in riparian (streamside) conditions.
VEGETATED ROOFS
Vegetated systems installed on roofs that generally consist
of a waterproof layer, a root-barrier, drainage layer (optional),
growth media and suitable vegetation. Vegetated roofs store and eventually
evapotranspirate the collected rooftop rainfall; overflows may be
provided for larger storms.
VEGETATED SWALES
(1)
Vegetated earthen channels designed to convey and possibly treat
stormwater. These swales are not considered to be water quality BMPs.
(2)
Broad, shallow, densely vegetated, earthen channels designed
to treat stormwater while slowly infiltrating, evapotranspirating,
and conveying it. Swales should be gently sloping with low flow velocities
to prevent erosion. Check dams may be added to enhance performance.
VEGETATED/SURFACE BMP
A BMP designed to provide vegetative uptake and soil renovation
or surface infiltration of runoff. Capture/reuse BMPs are included
if the captured runoff is applied to vegetated areas. Examples include
bioretention and surface infiltration basins.
WATER QUALITY INSERTS
Any number of commercially available devices that are inserted
into storm inlets to capture sediment, oil, grease, metals, trash,
debris, etc.
WATERCOURSE
Any channel of conveyance of surface water having defined
bed and banks, whether natural or artificial, with perennial or intermittent
flow.
WATERS OF THIS COMMONWEALTH
Any and all rivers, streams, creeks, rivulets, impoundments,
ditches, watercourses, storm sewers, lakes, dammed water, wetlands,
ponds, springs, and all other bodies or channels of conveyance of
surface and underground water, or parts thereof, whether natural or
artificial, within or on the boundaries of this commonwealth.
WATERSHED
Region or area drained by a river or other body of water
whether natural or artificial.
WET DETENTION PONDS
A basin that provides for necessary stormwater storage as
well as a permanent pool of water. To be successful, wet ponds must
have adequate natural hydrology (both runoff inputs as well as oils
and water table which allow for maintenance of a permanent pool of
water) and must be able to support a healthy aquatic community so
as to avoid creation of mosquito and other health and nuisance problems.
WETLAND
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.