For the purposes of this chapter, 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 number 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 words "shall" and "must" are mandatory; the words "may" and "should"
are permissive.
D.
AGRICULTURAL ACTIVITY
APPLICANT
BASINS
(1)
(2)
BEST MANAGEMENT PRACTICE (BMP)
BUILDING PERMIT
CONSERVATION DISTRICT
CUT
DEP
DESIGN STORM
DETENTION VOLUME
DEVELOPER
DEVELOPMENT
DEVELOPMENT SITE (SITE)
DISCHARGE
DISTURBED AREA
EARTH DISTURBANCE ACTIVITY
EARTHMOVING
EROSION
EROSION AND SEDIMENT CONTROL PLAN
EXCAVATION
EXISTING CONDITION
FEMA
FILL
(1)
(2)
(3)
FLOODPLAIN
FLOODPLAIN CONSERVATION DISTRICT
FLOODPLAIN SOILS
FLOODWAY
FOREST MANAGEMENT/TIMBER OPERATIONS
GRADE
GREEN INFRASTRUCTURE
GROUNDWATER RECHARGE
HYDROLOGIC SOIL GROUP (HSG)
IMPERVIOUS SURFACE (IMPERVIOUS AREA)
KARST
LAND DEVELOPMENT
LOW-IMPACT DEVELOPMENT (LID)
MINOR EARTH DISTURBANCE PERMIT
MUNICIPALITY
NPDES
NRCS
OUTFALL
PEAK DISCHARGE
PERSON
PERVIOUS AREA
POINT SOURCE
PROJECT SITE
QUALIFIED PROFESSIONAL
RATIONAL METHOD
REDEVELOPMENT
REGULATED ACTIVITIES
REGULATED EARTH DISTURBANCE ACTIVITY
RETENTION VOLUME/REMOVED RUNOFF
RETURN PERIOD
RIPARIAN BUFFER
RIPARIAN CORRIDOR CONSERVATION DISTRICT
ROAD MAINTENANCE
RUNOFF
RUNOFF FROM A FULLY DEVELOPED AREA UPSTREAM
SEDIMENT
SEDIMENTATION
SEPARATE STORM SEWER SYSTEM
SITE
SLOPE
SOIL COVER COMPLEX METHOD
SOIL STABILIZATION
STATE WATER QUALITY REQUIREMENTS
STEEP SLOPES
STORMWATER
STORMWATER MANAGEMENT FACILITY
STORMWATER MANAGEMENT SITE PLAN
STORMWATER MANAGEMENT SYSTEM
STRIPPING
SUBDIVISION
TIME OF CONCENTRATION
TOWNSHIP
TOWNSHIP ENGINEER
TOWNSHIP SOLICITOR
USDA
WATERS OF THIS COMMONWEALTH
WATERSHED
WETLAND
These definitions do not necessarily reflect the definitions contained
in pertinent regulations or statutes, and are intended for this chapter
only.
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.
A landowner, developer, or other person who has filed an
application to the Township for approval to engage in any regulated
activity at a project site in the Township.
DETENTION BASINSBasins designed for temporary storage of stormwater to reduce peak discharges. They are characterized by shorter detention periods and are normally dry, except for short periods following a storm event. Stored stormwater is released at a controlled rate.
RETENTION BASINSBasins designed for impoundment of stormwater to reduce peak discharges. They are usually wet continually but are designed to store excess stormwater above the normal pool elevation. The excess stormwater is released at a controlled rate.
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.
A permit issued by the Building Inspector pursuant to provisions
of the Whitemarsh Township Building Code for the construction, erection,
or alteration of a structure or building.
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 102.
An excavation; the difference between a point on original
ground and a designated point of lower elevation on the final grade;
also, the material removed in excavation.
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
five-year storm) and duration (e.g., 24 hours) used in the design
and evaluation of stormwater management systems. Also see "return
period."
The volume of runoff that is captured and released into the
waters of the commonwealth at a controlled rate.
A person that seeks to undertake any earth disturbance activities
regulated by the provisions of this chapter at a project site in the
Township.
See earth disturbance activity. The term includes redevelopment.
See "project site."
The outflow of water, silt or other mobile substances passing
along a conduit, watercourse or channel or released from any type
of detention or stormwater management feature.
An unstabilized land area where an earth disturbance activity
is occurring or has occurred.
A construction or other human activity which disturbs the
surface of the land, including, but not limited to: clearing and grubbing;
grading; certain paving; excavations; filling; stripping; grading;
regrading; cutting; removal of vegetation or natural ground covers;
digging; earthmoving; embankments; road maintenance; building construction;
and the moving, depositing, stockpiling, or storing of soil, rock,
or earth materials; or land development undertaken by an individual
on private or public property as herein set forth.
An activity resulting in the movement of earth or stripping
of vegetative cover from the earth.
The natural process by which the surface of the land is worn
away by water, wind, or chemical action.
A plan for a project site which identifies BMPs to minimize
accelerated erosion and sedimentation.
Any act by which earth, sand, gravel, rock or any other similar
materials is cut into, dug, quarried, uncovered, removed, displaced,
relocated, or bulldozed and shall include the conditions resulting
therefrom.
The dominant land cover during the five-year period immediately
preceding a proposed regulated activity.
Federal Emergency Management Agency.
The act by which earth, sand, gravel, rock or any other material
is deposited in a new location above the natural surface of the ground
or on top of the strip surface and shall include the conditions resulting
therefrom.
The difference in elevation between a point on the original
ground and a designated point of final elevation in the final grade.
The material used to make a fill.
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).
The floodplain soils shall include any one or combination
of the following soil classifications as defined in the Soil Survey
of Montgomery County, Pennsylvania, prepared by the United States
Department of Agriculture, Soil Conservation Service: Bermudian silt
loam, Bouldery alluvial land, Bowmansville silt loam, Codorus silt
loam, Hatboro silt loam and Rowland silt loam. The soil survey can
be referenced at: https://www.nrcs.usda.gov/wps/portal/nrcs/surveylist/soils/survey/state/?stateld=PA
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.
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.
The elevation of the existing ground surface or the finished
elevation at the location of any proposed excavation or fill.
Systems and practices that use or mimic natural processes
to infiltrate, evapotranspire, or reuse stormwater on the site where
it is generated.
Replenishment of existing natural underground water supplies.
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) according to their
minimum infiltration rate, which is obtained for bare soil after prolonged
wetting. The 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 pervious as the
HSG varies from A to D (NRCS).
A surface that prevents the infiltration of water into the
ground. Impervious surfaces (or areas) shall include, but not be limited
to: all buildings, parking areas, driveways, roads, sidewalks, and
any areas in concrete, asphalt and packed stone shall be considered
impervious surfaces within this definition. Any surface areas designed
to initially be gravel or crushed stone shall be assumed to be impervious
surfaces. In addition, other areas determined by the Township Engineer
to be impervious within the meaning of this definition will also be
classed as impervious surfaces.
A type of topography or landscape characterized by surface
depressions, sinkholes, rock pinnacles/uneven bedrock surface, underground
drainage, and caves. Karst is formed on carbonate rocks, such as limestone
or dolomite.
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.
Any permit required under § 58-13 hereof.
Whitemarsh Township, Montgomery County, Pennsylvania.
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.
USDA Natural Resources Conservation Service (previously SCS).
"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.
The maximum rate of stormwater runoff from a specific storm
event.
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.
Surfaces that release as runoff a small portion of the precipitation
that falls on it. Examples of pervious surfaces include meadow, grass,
mulched groundcover, planted areas, and vegetated roofs.
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.
The specific area of land where any regulated activities
in the Township 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
chapter.
The Rational Equation is as follows:
|
Q = CIA
| ||
|
where:
| ||
|
Q
|
=
|
Maximum expected discharge in cubic feet per second
|
|
C
|
=
|
Runoff factor expressed as a percent of the total water falling
on an area that is dependent upon the land cover of the watershed
|
|
I
|
=
|
The rate of rainfall from the time of concentration of the drainage
area in inches per hour for a given storm frequency
|
|
A
|
=
|
Drainage area expressed in acres
|
Earth disturbance activities on land which has previously
been disturbed or developed.
Any earth disturbance activities or any activities that involve
the alteration or development of land in a manner that may affect
stormwater runoff.
Earth disturbance activity of 10,000 square feet or more.
This includes earth disturbance on any portion of, part of, or during
any stage of, a larger common plan of development. This only includes
road maintenance activities involving 25 acres or more of earth disturbance.
All requirements of a minor earth disturbance permit and/or a subdivision/land
development application shall also apply to these activities.
The volume of runoff that is captured and not released directly
into the surface waters of this 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 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).
A permanent area of trees, shrubs and/or other vegetation
located adjacent to streams, lakes, ponds and wetlands.
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.
Any part of precipitation that flows over the land.
The surface water runoff that can be reasonably anticipated
upon maximum development of the area of the watershed upstream from
the subject tract, as permitted by prevailing zoning or the Township
Comprehensive Plan.
Soils or other materials transported by surface water as
a product of erosion.
The process by which mineral or organic matter is accumulated
or deposited by moving wind, water or gravity. Once this matter is
deposited, or remains suspended in water, it shall be referred to
as "sediment."
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.
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.
The face of an embankment or cut section; any ground where
surface makes an angle with the plane of the horizon. Slopes shall
be expressed as a ratio of horizontal distance to vertical or in a
percentage based upon vertical difference in feet per 100 feet of
horizontal distance.
A mathematical formula to compute runoff developed by the
Soil Conservation Service of the U.S. Department of Agriculture, which
provides for accurate consideration of the effect of applied conservation
measures on runoff rates and volume.
Chemical, physical, or structural treatment of a mass of
soil to increase or maintain stability or otherwise improve its engineering
properties.
The regulatory requirements to protect, maintain, reclaim,
and restore water quality under Title 25 of the Pennsylvania Code
and the Clean Streams Law.
Drainage runoff from the surface of the land resulting from
precipitation or snow or ice melt.
Any structure, natural or man-made, that, due to its condition,
design, or construction, conveys, stores, or otherwise affects stormwater
runoff. Typical stormwater management facilities include, but are
not limited to: detention and retention basins; open channels; storm
sewers; pipes; and infiltration facilities.
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
may also be designated as SWM site plan throughout this chapter.
Facilities used for conveying to, through or from a drainage
area to a point of final outlet, including but not limited to the
following: conduits and pertinent features, canals, channels, swales,
ditches, streams, culverts, streets, ponds and basins.
The removal of vegetation, including trees, and/or topsoil.
The normal process of gardening or property maintenance shall be excluded
from this definition.
The interval of time required for water to travel from the
most hydraulically distant point of the drainage area to a given point
(point of reference).
Whitemarsh Township, Montgomery County, Pennsylvania.
A professional engineer registered in the State of Pennsylvania
and designated by the Board of Supervisors to perform the duties of
engineer as herein specified.
An attorney designated by the Board of Supervisors to perform
the duties of a solicitor as herein specified.
United States Department of Agriculture.
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.
Region or area drained by a river, watercourse, or other
surface water of this commonwealth.
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.
