The following words and phrases, when used in this chapter, shall
have, unless the context clearly indicates otherwise, the meanings
given to them in this section. All words and terms not defined herein
shall be used with a meaning of standard usage.
ALTERATIONS
As applied to land, a change in topography as a result of
the moving of soil and/or rock from one location or position to another;
also the changing of surface conditions by causing the surface to
be more or less impervious; earth disturbance.
APPLICANT
A landowner or developer who has filed an application for
a zoning permit or subdivision approval.
BEDROCK
The solid, undisturbed rock in place either at the ground
surface or beneath surficial soil deposits.
BEST MANAGEMENT PRACTICE (BMP)
Activities, facilities, designs, measures, or procedures
used to manage stormwater impacts from regulated activities, to meet
state water quality requirements, to promote groundwater recharge,
and to otherwise meet the purposes of this 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.
BORROW PIT
An open pit from which soil is excavated as a single incident
for use at a single construction site.
CONSERVATION DISTRICT
The Montgomery County Conservation District. A conservation
district, as defined in Section 3(c) of the Conservation District
Law [3 P. S. § 851(c)] that has the authority under a delegation
agreement executed with DEP to administer and enforce all or a portion
of the regulations promulgated under 25 Pa. Code Chapter 102.
DEP
The Pennsylvania Department of Environmental Protection.
DESIGN STORM
The magnitude of precipitation from a storm event against
which stormwater management facilities shall be designed as protection,
measured in probability of occurrence/frequency (e.g., ten-year storm)
and duration (e.g., twenty-four-hour).
DETENTION BASIN
A structure formed from soil or other material which is designed
to temporarily detain a certain amount of stormwater runoff from a
designated watershed area.
DEVELOPER
Any record owner of land or authorized agent of such landowner
who files application to make or cause or makes or causes to be made
a subdivision of land or a land development. Written evidence of authority
to act for the record owner shall be filed with the application or
plan when signed by a person other than the record owner.
DEVELOPMENT
Any man-made change to improved or unimproved real estate,
including but not limited to land development; the construction of
buildings or other structures; and the placement of mobile homes,
streets and other paving, utilities, mining, dredging, filling, grading,
excavation or drilling operations.
EARTH DISTURBANCE
Changes in the contour of the land, grading, excavating,
removal or destruction of the topsoil or removal of trees or other
vegetative cover of the land.
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. Earth disturbance activity is subject to regulation
under 25 Pa. Code Chapter 92, 25 Pa. Code Chapter 102, or the Clean Streams Law.
EARTHMOVING
Any act by which soil or bedrock is cut into, quarried, displaced
or relocated.
EROSION
The removal of surface materials by the action of natural
elements.
EXCAVATION
An act by which earth, sand, gravel, rock or any other material
is removed, dug out, grubbed, hollowed out or moved from an existing
location.
EXISTING GRADE
The vertical elevation of the ground surface prior to earthmoving
or filling.
FILL
Any act by which earth, sand, gravel, rock or any other material
is deposited, placed, pushed, dumped, pulled, transported or moved
to a new location and shall include the conditions resulting therefrom.
FINISHED GRADE
The final vertical elevation of the ground after development.
FLOODPLAIN
That area defined in Article
XXXII of the Township Zoning Ordinance as the Floodplain Conservation District; the "floodplain"
definition contained therein is made part of the chapter by reference.
GRADING
The changing of the grade of the existing ground surface
of the site by excavation or filling or a combination of both.
GROUNDWATER RECHARGE
Replenishment of geologic structures and rock or soil interstices
which have the capacity to store water.
IMPERVIOUS SURFACE
Material which is impenetrable to or unable to absorb water,
including but not limited to buildings, structures and paved areas
(driveways, parking lots, etc.).
INFILTRATION STRUCTURE
A structure designed to direct the flow of rain into storage
in geologic structures, e.g., french drains, seepage pits.
LAND DEVELOPMENT
Any of the following activities:
(1)
The improvement of one lot or two or more contiguous lots, tracts
or parcels of land for any purpose involving:
(a)
A group of two or more residential or nonresidential buildings,
whether proposed initially or cumulatively, or a single nonresidential
building on a lot or lots regardless of the number of occupants or
tenure.
(b)
The division or allocation of land or space, whether initially
or cumulatively, between or among two or more existing or prospective
occupants by means of or for the purpose of streets, common areas,
leaseholds, condominiums, building groups or other features.
(c)
The addition of any impervious or semipervious material to a
nonresidential lot or residential lot, except a single-family detached
residential lot.
MUNICIPALITY
Upper Merion Township, Montgomery County, Pennsylvania.
NATURAL GROUND SURFACE
The ground surface in its original state before any earthmoving,
filling, stripping or other development activity.
NONSTORMWATER DISCHARGE
Any discharge that does not fall under the definition of
"stormwater," including but not limited to sewage, processed wastewater,
washwater, sump pump discharge, pool water, and groundwater.
NPDES
National Pollutant Discharge and Elimination System.
NRCS
Natural Resources Conservation Service, United States Department
of Agriculture, previously known as the "Soil Conservation Service
(SCS)."
OPEN-PIT MINING
The continuing or recurring removal of material from below
the ground surface by open excavation.
PEAK DISCHARGE
The maximum rate at which stormwater discharges or leaves
a site at a given point and time resulting from a specified storm
event. Peak discharge shall be measured in cubic feet per second.
PERSON
Any individual, corporation, partnership, joint venture,
agency, unincorporated association, municipal corporation, Commonwealth
of Pennsylvania agency or any combination thereof.
RATIONAL METHOD
A method for computing quantities of stormwater runoff. The
Rational Formula relates runoff to rainfall by the following:
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Q = CIA
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Where:
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Q
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=
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Peak runoff rate in cubic feet per second.
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C
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=
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Runoff coefficient (assumed dimensionless), often taken as a
fraction of rainfall that runs off.
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|
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I
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=
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Design rainfall intensity in inches per hour lasting for a critical
time equal to the time of concentration.
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|
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A
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=
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Drainage area in acres.
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REGULATED ACTIVITIES
Any activities that may affect stormwater runoff and any
activities that may contribute nonstormwater discharges to a regulated
small MS4.
RETENTION BASIN
A structure formed from soil or other material which is designed
to retain permanently a certain amount of stormwater from a designated
watershed area and which also may be designed to detain water from
a designated watershed area. Retention basins also may receive fresh
water from year-round streams. Unlike detention basins, retention
basins always contain water and thus may be considered man-made lakes
or ponds.
RUNOFF
The surface water discharge of a given watershed after a
fall of rain or snow that does not enter the soil but runs off the
surface of the land.
SEDIMENT
Solid material, both mineral and organic, that is in suspension,
is being transported, or has been moved from its site of origin by
water.
SEDIMENTATION BASIN
A basin located and designed to retain rock, sand, gravel,
silt or other water-transported material. Sedimentation basins are
intended to provide a control structure that prevents sediment pollution.
SEEPAGE BED
Any device which directs stormwater for infiltration into
the ground.
SEMIPERVIOUS SURFACE
Material which is initially slightly penetrable by water
when first constructed but which becomes impervious or mostly impervious
over time.
SITE
A lot, tract or parcel of land or a series of lots, tracts
or parcels of land joined together, where grading work is continuous
and performed at the same time.
SOIL
All earth material of whatever origin that overlies bedrock.
SOIL-COVER COMPLEX METHOD
A mathematical method of runoff computation developed by
the NRCS of the United States Department of Agriculture as published
in the 1986 or latest edition of Urban Hydrology for Small Watersheds
(Technical Release No. 55).
STABILIZATION
The proper placing, grading and/or covering of soil, rock
or earth to ensure their resistance to erosion, sliding or other movement.
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.
STORM SEWER
A system of pipe or other conduits which carries intercepted
surface runoff, street water or drainage, excluding domestic sewage
and industrial wastes.
STORMWATER
The runoff from the surface of the land resulting from precipitation,
snow or ice melt. This includes runoff from roofs and other impervious
surfaces.
STORMWATER MANAGEMENT
The set of actions taken to control water in its hydrological
cycle with the objective of providing surface drainage and flood control,
erosion and sedimentation control and achieving a reduction of pollutants
in stormwater runoff.
STREAM
A natural body of water draining a watershed to a river.
In Upper Merion, only bodies of water identified as streams on the
most recent version of the United States Geological Survey (USGS)
7 1/2-minute quadrangles shall be considered streams.
STRIPPING
The removal of vegetation, including trees and/or topsoil.
Stripping shall not include, or be deemed to include, the normal process
of gardening or property maintenance.
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.
USDA
United States Department of Agriculture.
WATERCOURSE
A permanent stream, intermittent stream, river, brook, creek
or a channel or ditch for water, whether natural or man-made.
WATERSHED
The entire region or area drained by a river or other body
of water, whether natural or artificial; a drainage basin or subbasin.
For Upper Merion Township, watersheds are identified in the Township-Wide
Stormwater Management Plan.
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.
WETLANDS
Those areas inundated or saturated by surface water or groundwater
at a frequency and duration sufficient to support, and that under
normal circumstances do support, a prevalence of vegetation typically
adapted for life in saturated soil conditions, including swamps, marshes,
bogs and similar areas. The term includes, but is not limited to,
wetland areas listed in the State Water Plan, the United States Fish
and Wildlife Service Wetlands Inventory of Pennsylvania, the Pennsylvania
Coastal Zone Management Plan and any wetland area designated by a
river basin commission.