As used in this chapter, the following terms shall have the
meanings indicated:
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 ACTIVITIES
The work of producing crops and raising livestock including
tillage, plowing, disking, harrowing, pasturing and installation of
conservation measures. Construction of new buildings or impervious
area is not considered an agricultural activity.
ALTERATION
As applied to land, a change in topography as a result of
the moving of soil and rock from one location or position to another;
also the changing of surface conditions by causing the surface to
be more or less impervious; land disturbance.
APPLICANT
A person who has filed an application for approval to engage in any regulated activity defined in §
430-301 of this chapter.
AS-BUILT DRAWINGS
Engineering or site drawings maintained by the contractor
as he constructs the project and upon which he documents the actual
locations of the building components and changes to the original contract
documents. These documents, or a copy of same, are turned over to
the Township Engineer at the completion of the project, and shall
be submitted in an electronic format of such type as is designated
by the Township.
BANKFULL
The channel at the top-of-bank, or point from where water
begins to overflow onto a floodplain.
BASEFLOW
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)
Methods, measures or practices used to prevent or reduce
surface runoff and/or water pollution, including but not limited to
structural and nonstructural stormwater management practices and operation
and maintenance procedures. See also "nonstructural best management
practice (BMP)."
BMP OPERATIONS AND MAINTENANCE PLAN
A plan prepared by the developer or his representative indicating
how stormwater runoff will be managed at the particular site of interest
according to this chapter.
BUFFER
The area of land immediately adjacent to any natural watercourse,
measured perpendicular to and horizontally from the top-of-bank on
both sides of a stream (see "top-of-bank").
CHANNEL
An open drainage feature through which stormwater flows.
Channels include, but shall not be limited to, natural and man-made
drainageways, swales, streams, ditches, canals and pipes flowing partly
full.
CHANNEL EROSION
The widening, deepening or headward cutting of channels and
waterways caused by stormwater runoff or bankfull flows.
CISTERN
An underground reservoir or tank for storing rainwater.
CULVERT
A structure with its appurtenant works which carries water
under or through an embankment or fill.
DAM
A man-made barrier, together with its appurtenant works,
constructed for the purpose of impounding or storing water or another
fluid or semifluid. A dam may include a refuse bank, fill or structure
for highway, railroad or other purposes which impounds or may impound
water or another fluid or semifluid.
DEPARTMENT
The Pennsylvania Department of Environmental Protection.
DESIGN PROFESSIONAL (QUALIFIED)
A Pennsylvania registered professional engineer, registered
landscape architect or registered professional land surveyor trained
to develop stormwater management plans.
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.
DESIGNEE
The agent or representative of Middletown Township responsible
for the administration, review and/or enforcement of any provisions
of this chapter by appointment, resolution, contract or memorandum
of understanding.
DETENTION BASIN
An impoundment designed to collect and retard stormwater
runoff by temporarily storing the runoff and releasing it at a predetermined
rate. Detention basins are designed to drain completely soon after
a rainfall event and become dry until the next rainfall event.
DETENTION DISTRICT
Those subareas of a watershed in which some type of detention
is required to meet the plan requirements and the goals of Act 167.
DEVELOPER
A person that seeks to undertake any regulated earth disturbance
activities at a project site in the Township.
DEVELOPMENT
Any human-induced change to improved or unimproved real estate,
whether public or private, including but not limited to land development,
construction, installation or expansion of a building or other structure,
land division, street construction, drilling and site alteration,
such as embankments, dredging, grubbing, grading, paving, parking
or storage facilities, excavation, filling, stockpiling or clearing.
As used in this chapter, development encompasses both new development
and redevelopment.
DEVELOPMENT SITE
The specific tract or parcel of land where any regulated activity set forth in §
430-301 is planned, conducted or maintained.
DIFFUSED DRAINAGE DISCHARGE
Drainage discharge that is not confined to a single point
location or channel, including sheet flow or shallow concentrated
flow.
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 (noun). See also "peak discharge."
DISTURBED AREAS
Unstabilized land area where an earth disturbance activity
is occurring or has occurred.
DITCH
A man-made waterway constructed for irrigation or stormwater
conveyance purposes.
DOWNSLOPE 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 project site would be directed towards it by gravity.
DRAINAGE CONVEYANCE FACILITY
A stormwater management facility designed to transport stormwater
runoff that includes channels, swales, pipes, conduits, culverts and
storm sewers.
DRAINAGE EASEMENT
A right granted by a landowner to a grantee, allowing the
use of private land for stormwater management purposes.
DRAINAGE PERMIT
A permit issued by the Township after the drainage plan has
been approved.
DRAINAGE PLAN
The documentation of the stormwater management system, if any, to be used for a given development site, the contents of which are established in §
430-302.
EARTH DISTURBANCE ACTIVITY
A construction or other human activity which disturbs the
surface of land, including, but not limited to, clearing and grubbing,
grading, excavations, embankments, land development, agricultural
plowing or tilling, timber harvesting activities, road maintenance
activities, mineral extraction, and the moving, depositing, stockpiling,
or storing of soil, rock or earth materials.
EARTH DISTURBANCE PERMIT
A permit issued by the Township Department of Licenses and
Inspections for any earth disturbance activity.
EMERGENCY SPILLWAY
A conveyance area that is used to pass peak discharge greater
than the maximum design storm controlled by the stormwater facility.
ENCROACHMENT
A structure or activity that changes, expands or diminishes
the course, current or cross section of a watercourse, floodway or
body of water.
EROSION
The process by which the surface of the land, including water/stream
channels, is worn away by water, wind or chemical action.
EROSION AND SEDIMENT CONTROL PLAN
A plan that is designed to minimize accelerated erosion and
sedimentation. Said plan must be submitted to and approved by the
appropriate conservation district before construction can begin.
ERSAM
Existing resource and site analysis map.
EXCAVATION
Any act by which earth, sand, gravel, rock or any other similar
material is cut into, dug, quarried, uncovered, removed, displaced
or relocated and shall include the conditions resulting therefrom.
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 antidegradation).
EXISTING CONDITIONS
The initial condition of a project site prior to its proposed
alteration. If the initial condition of the site is undeveloped land,
the land use shall be considered as "meadow" unless the natural land
cover is proven to generate lower curve numbers or Rational "C" value,
such as forested lands.
FINANCIAL SECURITY
An irrevocable letter of credit with a federal or commonwealth
lending institution, a corporate surety bond from a bonding company
authorized to do business within the commonwealth or such other guaranty
approved by the Solicitor in an amount approved by the Township Engineer.
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 as delineated by applicable Department of Housing
and Urban Development, Federal Insurance Administration Flood Hazard
Boundary Map as being a special flood hazard area.
FLOODPLAIN SOILS
Soils in areas subject to periodic flooding and listed in
the Soil Survey of Bucks and Philadelphia Counties, Pennsylvania,
United States Department of Agriculture, Soil Conservation Service,
July 1975, as being "in the floodplain" or "subject to flooding."
Floodplain soils include but are not limited to:
B.
Alton gravelly loam, flooded.
FLOODWAY
The channel of a watercourse and those portions of the adjoining
floodplains, which 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-bank.
FLUVIAL GEOMORPHOLOGY
The study of landforms associated with river channels and
the processes that form them.
FOREST MANAGEMENT/TIMBER OPERATIONS
Planning and associated 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 and reforestation.
FREEBOARD
A vertical distance between the elevation of the design high-water
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 (noun); to finish
the surface of a roadbed, the top of an embankment, or the bottom
of excavation (verb).
GRASSED WATERWAY
A natural or man-made waterway, usually broad and shallow,
covered with erosion-resistant grasses, used to convey surface water.
GROUND COVER
Low-growing plant materials planted and growing in such a
manner so as to conceal the earth surface.
GROUNDWATER
Water beneath the earth's surface that supplies wells
and springs, and is often between saturated soil and rock.
GROUNDWATER RECHARGE
The replenishment of existing natural underground water supplies
from rain or overland flow.
HEC-HMS
The United States Army Corps of Engineers, Hydrologic Engineering
Center (HEC) - Hydrologic Modeling System (HMS). This model was used
to model the Neshaminy and Little Neshaminy Creeks watershed during
the Act 167 Plan development and was the basis for the standards and
criteria of this chapter.
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).
HOT SPOTS
Areas where land use or activities generate highly contaminated
runoff, with concentrations of pollutants in excess of those typically
found in stormwater.
HYDROGRAPH
A graph representing the discharge of water versus time for
a selected point in the drainage system.
HYDROLOGIC REGIME
The hydrologic cycle or balance that sustains quality and
quantity of stormwater, baseflow, storage and groundwater supplies
under natural conditions.
HYDROLOGIC SOIL GROUP
A classification of soils by the Natural Resources Conservation
Service, formerly the Soil Conservation Service, into four runoff
potential groups. The groups range from A soils, which are very permeable
and produce little runoff, to D soils, which are not very permeable
and produce much more runoff.
HYETOGRAPH
A graphical representation of average rainfall, rainfall
excess rates, or volumes over specified areas during successive units
of time during a storm.
IMPERVIOUS SURFACE
A surface that prevents the infiltration of water into the
ground. Impervious surfaces include, but are not limited to, streets,
sidewalks, pavement roofs or driveway areas. Any surface areas designed
to be gravel or crushed stone shall be regarded as impervious surfaces.
IMPOUNDMENT
A retention or detention basin designed to retain stormwater
runoff and release it at a controlled rate.
INFILL
Development that occurs on smaller parcels that remain undeveloped
but are within or in very close proximity to urban or densely developed
areas. Infill development usually relies on existing infrastructure
and does not require an extension of water, sewer or other public
utilities.
INFILTRATION
Movement of surface water into the soil, where it is absorbed
by plant roots, evaporated into the atmosphere, or percolated downward
to recharge groundwater.
INFILTRATION STRUCTURES
A structure designed to direct runoff into the underground
water (e.g., french drains, seepage pits, or seepage trenches).
INFILTRATION TEST
An in-situ test performed in accordance with the current
standards as stated in the Pennsylvania Code, Title 25, Environmental
Protection, Chapter 73 (Standards for On-lot Sewage Treatment Facilities)
by a qualified soil scientist or geotechnical engineer to determine
the permeability or percolation capacity of an area for use in designing
any infiltration BMPs. The number and locations of infiltration tests
shall be in accordance with Pennsylvania Stormwater Best Management
Practices Manual (Draft January 2005, Section 6.9, Protocol 1).
INLET
The upstream end of any structure through which water may
flow.
INTERMITTENT STREAM
A stream that flows only part of the time. Flow generally
occurs for several weeks or months in response to seasonal precipitation
or groundwater discharge.
LAND DEVELOPMENT
Any of the following activities:
A.
The improvement of one lot or two or more contiguous lots, tracts
or parcels of land for any purpose involving:
(1)
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
(2)
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.
C.
Development in accordance with Section 503(1.1) of the Pennsylvania
Municipalities Planning Code.
D.
The following shall not be considered a land development:
(1)
The conversion of an existing single-family detached dwelling
or single-family semidetached dwelling into not more than three residential
units, unless such units are intended to be a condominium;
(2)
The addition of an accessory building, including farm building,
on a lot or lots, subordinate to an existing principal building; or
(3)
The addition or conversion of buildings or rides within the
confines of an enterprise which would be considered an amusement park.
For the purposes of this exemption, an amusement park is defined as
a tract or area used principally as a location for permanent amusement
structures or rides. This exclusion shall not apply to newly acquired
acreage by an amusement park until initial plans for the expanded
area have been approved by the municipality.
LIMITING ZONE
A soil horizon or condition in the soil profile or underlying
strata that includes one of the following:
A.
A seasonal high-water table, whether perched or regional, determined
by direct observation of the water table or indicated by soil mottling.
B.
A rock with open joints, fracture or solution channels, or masses
of loose rock fragments, including gravel, with insufficient fine
soil to fill the voids between the fragments.
C.
A rock formation, other stratum or soil condition that is so
slowly permeable that it effectively limits downward passage of effluent.
LOT
A designated parcel, tract or area of land established by
a plat or otherwise as permitted by law and to be used, developed
or built upon as a unit.
MAIN STEM (MAIN CHANNEL)
Any stream segment or other runoff conveyance used as a reach
in the Neshaminy and Little Neshaminy Creeks hydrologic model.
MANAGER
The Manager of Middletown Township, Bucks County, Pennsylvania,
or other person so designated by the Board of Supervisors.
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.
NATURAL RECHARGE AREA
Undisturbed surface area or depression where stormwater collects,
and a portion of which infiltrates and replenishes the groundwater.
NONPOINT SOURCE POLLUTION
Pollution that enters a water body from diffuse origins in
the watershed and does not result from discernible, confined or discrete
conveyances.
NONSTORMWATER DISCHARGES
Water flowing in stormwater collection facilities, such as
pipes or swales, which is not the result of a rainfall event or snowmelt.
NONSTRUCTURAL BEST MANAGEMENT PRACTICE (BMP)
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 DEP in Pennsylvania.
NRCS
Natural Resource Conservation Service (previously Soil Conservation
Service).
OPEN CHANNEL
A drainage element in which stormwater flows with an open
surface. Open channels include, but shall not be limited to, natural
and man-made drainageways, swales, streams, ditches and canals.
OUTFALL
"Point source" as described in 40 CFR 122.2 at the point
where the Township's storm sewer system discharges to surface
waters of the commonwealth.
OUTLET
Points of water disposal to a stream, river, lake, tidewater
or artificial drain.
PA DEP
The Pennsylvania Department of Environmental Protection.
PARENT TRACT
The parcel of land from which a land development or subdivision
originates, determined from the date of Township adoption of this
chapter.
PARKING LOT STORAGE
Involves 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.
PENN STATE RUNOFF MODEL (CALIBRATED)
The computer-based hydrologic modeling technique adapted
to the Delaware River South watershed for the Act 167 plan. The model
has been calibrated to reflect actual recorded flow values by adjoining
key model input parameters.
PERSON
An individual, partnership, public or private association,
corporation, partnership, limited liability company or a governmental
unit, public utility or any other legal entity whatsoever which is
recognized by law as the subject of rights and duties.
PERVIOUS SURFACE
A surface that allows the infiltration of water into the
ground.
PIPE
A culvert, closed conduit or similar structure (including
appurtenances) that conveys stormwater.
PMF (PROBABLE MAXIMUM FLOOD)
The flood that may be expected from the most severe combination
of critical meteorological and hydrologic conditions that are reasonably
possible in any area. The PMF is derived from the probable maximum
precipitation (PMP) as determined based on data obtained from the
National Oceanographic and Atmospheric Administration (NOAA).
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 during which disturbed areas are
stabilized, stormwater controls are in place and functioning and all
proposed improvements in the approved land development plan are completed.
PREDEVELOPMENT
Undeveloped/natural condition. (When applying recharge and
stormwater requirements meeting definition of "regulated activity,"
existing impervious coverage shall be considered as meadow conditions.)
PRETREATMENT
Techniques employed in stormwater BMPs to provide storage or filtering to trap coarse materials and other pollutants before they enter the system, but not necessarily designed to meet the water quality volume requirements of §
430-404.
PROJECT SITE
The specific area of land where any regulated activities
in the Township are planned, conducted or maintained.
RECHARGE
The replenishment of groundwater through the infiltration
of rainfall, other surface waters, or land application of water or
treated wastewater.
RECONSTRUCTION
The process by which existing developed area is adaptively
reused, rehabilitated, restored, renovated and/or expanded. The development
relies on existing infrastructure and does not require an extension
of water, sewer or other public utilities.
RECORD O&M PLAN
A copy of an approved BMP operations and maintenance plan
which contains the original required endorsements of the Township
and which is intended to be recorded with the Bucks County Recorder
of Deeds.
REDEVELOPMENT
Any development that requires demolition or removal of existing
structures or impervious surfaces at a site and/or the replacement
with new impervious surfaces. Maintenance activities such as top-layer
grinding and repaving are not considered to be redevelopment. Interior
remodeling projects and tenant improvements are also not considered
to be redevelopment. Utility trenches in streets are not considered
redevelopment unless more than 50% of the street width including shoulders
is removed and repaved.
REGULATED ACTIVITIES
Actions or proposed actions that have an impact on stormwater runoff quality or quantity and that are specified in §
430-105 of this chapter.
RELEASE RATE
The percentage of existing conditions peak rate of runoff
from a site or subarea to which the proposed conditions peak rate
of runoff must be reduced to protect downstream areas.
REPAVING
Replacement of the impervious surface that does not involve
reconstruction of an existing paved (impervious) surface.
REPLACEMENT PAVING
Reconstruction of and full replacement of an existing paved
(impervious) surface.
RETENTION BASIN
A structure in which stormwater is stored and not released
during the storm event. Retention basins are designed for infiltration
purposes and do not have an outlet. The retention basin must infiltrate
stored water in four days or less.
RETURN PERIOD
The average interval, in years, within which a storm event
of a given magnitude can be expected to recur. For example, the twenty-five-year
return period rainfall would be expected to recur on the average of
once every 25 years.
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
The temporary ponding and gradual release of stormwater falling
directly onto flat roof surfaces using controlled-flow roof drains
into building designs.
RUNOFF
Any part of precipitation that flows over the land surface.
RUNOFF COEFFICIENT
That portion of a total volume of water which can be expected
to flow off a particular surface.
SALDO
Subdivision and Land Development Ordinance; Chapter
440 of this Code.
SEDIMENT BASIN
A barrier, dam, retention or detention basin located and
designed in such a way as 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 underground water.
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 ruts 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.
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).
SOLICITOR
The Solicitor of Middletown Township, Bucks County, Pennsylvania.
SPECIAL PROTECTION SUBWATERSHEDS
Watersheds that have been designated in Pennsylvania Code,
Title 25, Environmental Protection, Chapter 93, Water Quality Standards,
as exceptional value (EV) or high quality (HQ) waters.
SPILLWAY
A conveyance that is used to pass the peak discharge of the
maximum design storm that is controlled by the stormwater facility.
STATE WATER QUALITY REQUIREMENTS
As defined under state regulations, protection of designated
and existing uses (see 25 Pa. Code, Chapters 93 and 96), including:
A.
Each stream segment in Pennsylvania has a designated use, such
as cold water fishery or potable water supply, which are listed in
Chapter 93. These uses must be protected and maintained under state
regulations.
B.
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.
C.
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 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 conveys intercepted
runoff and stormwater from other sources, but excludes domestic sewage
and industrial wastes.
STORMWATER
The surface runoff generated by precipitation reaching the
ground surface.
STORMWATER MANAGEMENT FACILITY
Any structure, natural or man-made, that, due to its condition,
design or construction, conveys, stores or otherwise affects stormwater
runoff quality, rate or quantity. 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 watershed plan known as the "Neshaminy and Little Neshaminy
Creeks or the Delaware River South Watershed Act 167 Stormwater Management
Plan" for managing those land use activities that will influence stormwater
runoff quality and quantity and that would impact the Neshaminy and
Little Neshaminy Creeks or the Delaware River South Watersheds, adopted
by Bucks County as required by the Act of October 4, 1978, P.L. 864
(Act 167).
STORMWATER MANAGEMENT SITE PLAN
The plan prepared by the applicant or his representative
indicating how stormwater runoff will be managed at the particular
site of interest according to this chapter.
STREAM BUFFER
The land area adjacent to each side of a natural stream,
essential to maintaining water quality. (See "buffer.") (Not man-made.)
STREAM ENCLOSURE
A bridge, culvert or other structure in excess of 100 feet
in length, upstream to downstream, which encloses a regulated water
of the commonwealth.
STRIPPING
The removal of vegetation, including trees and topsoil. The
normal process of gardening or property maintenance shall be excluded
from this definition.
SUBAREA (SUBWATERSHED)
The smallest drainage unit of a watershed for which stormwater
management criteria has been established in the stormwater management
plan.
SUBDIVISION
The division or redivision of a lot, tract or parcel of land
by any means into two or more lots, tracts, parcels or other divisions
of land, including changes in existing lot lines for the purpose,
whether immediate or future, of lease, partition by 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.
SURFACE WATERS OF THE 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 waters, or parts
thereof, whether natural or artificial, within or on the boundaries
of the commonwealth.
SWALE
A low-lying stretch of land that gathers or carries surface
water runoff.
TIME TO PEAK (Tp)
A factor used in conjunction with the application of the
Rational Method, which specifies a lag factor between the time of
concentration (Tc) and the peak runoff for a given watershed. For
purposes of this chapter, Tp shall equal 3 for the standard Rational
Method, 5 for the Modified Rational Method and 7 for the DeKalb Rational
Method.
TIME-OF-CONCENTRATION (Tc)
The time required for surface runoff to travel from the hydraulically
most distant point of the watershed to a point of interest within
the watershed. This time is the combined total of overland flow time
and flow time in pipes or channels, if any.
TOP-OF-BANK
Highest point of elevation in a stream channel cross section
at which a rising water level just begins to flow out of the channel
and over the floodplain.
TOWNSHIP
Middletown Township, Bucks County, Pennsylvania.
TOWNSHIP ENGINEER
A.
A professional engineer licensed as such in the Commonwealth
of Pennsylvania, duly appointed as the engineer for a township, planning
agency or joint planning commission.
B.
A professional engineer licensed as such in the Commonwealth
of Pennsylvania, duly appointed as the Engineer for the Township by
the Board of Supervisors to perform the duties of Engineer as herein
specified.
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 a defined
bed and banks, whether natural or artificial, with perennial or intermittent
flow.
WATERS OF THE 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 and underground
water, or parts thereof, whether natural or artificial, within or
on the boundaries of the commonwealth.
WATERSHED
Region or area drained by a river, watercourse or other body
of water; whether natural or artificial.
WELLHEAD
A.
A structure built over a well;
B.
The source of water for a well.
WELLHEAD PROTECTION AREA
The surface and subsurface area surrounding a water supply
well, well field, or spring supplying a public water system, through
which contaminants are reasonably likely to move toward and reach
the water source.
WET BASIN
Pond for urban runoff management that is designed to detain
urban runoff and always contains water.
WETLAND
Those areas that are inundated or saturated by surface water
or groundwater at a frequency and duration sufficient to support,
and that under normal circumstances do support, a prevalence of vegetation
typically adapted for life in saturated soil conditions. Wetlands
generally include swamps, marshes, bogs, fens and similar areas.
ZONING OFFICER
The Zoning Officer of Middletown Township, Bucks County,
Pennsylvania, so appointed by the Board of Supervisors.