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 those of feminine gender and vice
versa.
B.
The word "includes" or "including" shall not limit the term to the
specific example but is intended to extend its meaning to all other
instances of like kind and character.
C.
The word "person" includes an individual, firm, association, organization,
partnership, trust, company, corporation, or any other similar entity.
D.
The words "shall" and "must" are mandatory; the words "may" and "should"
are permissive.
E.
The words "used or occupied" include the words "intended," "designed,"
"maintained," or "arranged to be used or occupied."
G.
References to officially adopted regulations, standards, or publications
of PADEP or other governmental agencies shall include the regulation,
publication, or standard in effect on the date that a stormwater management
site plan is first filed. It is the intent of the Board of Supervisors
in enacting this section to incorporate such changes to statutes,
regulations, and publications to the extent authorized by 1 Pa.C.S.A.
§ 1937.
Specific terms or words used herein, unless otherwise expressly
stated, shall have the following meanings:
The removal of the surface of the land through the combined
action of man's activity and the natural processes at a rate greater
than would occur because of the natural process alone.
A right granted by a landowner to a grantee, allowing entry
for the purpose of inspecting, maintaining and repairing stormwater
management facilities.
A plan prepared under the authority of the Storm Water Management
Act.[1]
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
areas is not considered an agricultural activity.
As applied to land, a change in topography as a result of
the moving of soil and rock from one location or position to another;
also the changing of surface conditions by causing the surface to
be more or less impervious; any land disturbance.
A barnyard, feedlot, loading area, exercise lot, or other
similar area on an agricultural operation where, due to the concentration
of animals, it is not possible to establish and maintain vegetative
cover of a density capable of minimizing accelerated erosion and sedimentation
by usual planting methods. The term does not include entrances, pathways
and walkways between areas where animals are housed or kept in concentration.
A landowner or developer who has filed an application for approval to engage in any regulated activities as defined in § 122-5 of this chapter.
The Pennsylvania Storm Water Best Management Practices Manual
as published by the PADEP.
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: nonstructural
or structural. Nonstructural BMPs are measures referred to as operational
and/or behavior-related practices that attempt to minimize stormwater
runoff generation resulting from an alteration of the land surface
or the contact of pollutants with stormwater runoff, whereas structural
BMPs are measures that consist of a physical device or practice that
is installed to capture and treat stormwater runoff. Structural BMPs
include, but are not limited to, a wide variety of practices and devices,
from large-scale wet ponds and constructed wetlands, to small-scale
underground treatment systems, infiltration facilities, filter strips,
low impact design, bioretention, wet ponds, permeable paving, grassed
swales, riparian or forested buffers, sand filters, detention basins,
and manufactured devices. Structural stormwater BMPs are permanent
appurtenances to the project site.
The West Hempfield Township Board of Supervisors.
Any enclosed or open structure, other than a boundary wall
or fence, occupying more than four square feet of area and/or having
a roof supported by columns, piers, or walls.
Limestone or dolomite bedrock. Carbonate geology is often
associated with karst topography.
A reservoir or tank for storing rainwater.
The Lancaster County Conservation District or any agency
successor thereto.
A plan written by a National Resources Conservation Service-certified
planner that identifies conservation practices and includes site-specific
BMPs for agricultural plowing or tilling activities and animal heavy
use areas.
The ability of a pipe, culvert, swale or similar facility
to carry the peak flow from the design storm.
A structure with appurtenant works which carries a stream
under or through an embankment or fill.
An artificial barrier, together with its appurtenant works,
constructed for the purpose of impounding or storing water or another
fluid or semifluid, or a refuse bank, fill or structure for highway,
railroad or other purposes which does or may impound water or another
fluid or semifluid. The dam falls under the requirements of PADEP
Chapter 105, Dam Safety and Waterway Management, if any of the following
is true:
The Pennsylvania Department of Conservation and Natural Resources
and any agency successor thereto.
The Pennsylvania Department of Environmental Protection or
any agency successor to 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.
The agent of the Township involved with the administration,
review or enforcement of any provisions of this chapter.
An impoundment structure designed to manage stormwater runoff
by temporarily storing the runoff and releasing it at a predetermined
rate.
The volume of runoff that is captured and released into the
waters of this commonwealth at a controlled rate.
A person, partnership, association, corporation, or other
entity, or any responsible person therein or agent thereof, that undertakes
any regulated activity of this chapter.
The specific area of land for which a regulated activity
is proposed, planned, conducted or maintained.
A stream in an area underlain by limestone or dolomite which
flows underground for a portion of its length.
A land area where an earth disturbance activity is occurring
or has occurred.
A right granted by a landowner to a grantee, allowing the
use of private land for stormwater management, drainage, or conveyance
purposes.
A construction or other human activity which disturbs the
surface of the land, including, but not limited to: clearing and grubbing;
grading; excavations; embankments; land development; agricultural
plowing or tilling; operation of animal heavy use areas; timber harvesting
activities; road maintenance activities; oil and gas activities; well
drilling; mineral extraction; building construction; and the moving,
depositing, stockpiling, or storing of soil, rock, or earth materials.
An area that has slopes greater than 15%, shallow bedrock
(located within six feet of ground surface), wetlands, natural heritage
areas and other areas designated as conservation or preservation areas
in Greenscapes, the green infrastructure element of the County Comprehensive
Plan, where encroachment by land development or land disturbance results
in degradation of the natural resource.
A transient stream; one that flows for a relatively short
time.
The movement of soil particles by the action of water, wind,
ice, or other natural forces.
A plan which is designed to minimize accelerated erosion
and sedimentation.
The initial condition of a project site prior to the proposed
regulated activity. If the initial condition of the site is not forested
or undeveloped land, the land use shall be considered as meadow unless
the natural land cover is documented to generate lower curve numbers
or rational "C" coefficients, such as forested lands.
For aboveground detention/retention/BMP facilities, the facility
depth is defined to be the depth between the bottom invert of the
lowest orifice and the invert of the spillway. If there is no spillway,
the top of the berm shall be used. For basins with no orifices or
outlet structure, the bottom elevation of the basin shall be used.
The Federal Emergency Management Agency or any agency successor
thereto.
A general but temporary condition of partial or complete
inundation of normally dry land areas from the overflow of streams,
rivers, and other waters of this commonwealth.
Act of October 4, 1978, P.L. 851, No. 166, as amended 32
P.S. § 679.101 et seq., and as may be amended in the future.
That portion of the floodplain outside of the floodway.
See the most recent version of the Zoning Ordinance of West
Hempfield Township.[2]
See the most recent version of the Zoning Ordinance of West
Hempfield Township.[3]
Planning and activities necessary for the management of forest
land. These include timber inventory and preparation of forest management
plans, silvicultural treatment, cutting budgets, logging road design
and construction, timber harvesting, site preparation and reforestation.
A vertical distance between the one-hundred-year design elevation
of the water surface at the emergency spillway, in a condition that
assumes the primary outlet(s) are blocked, and the top of a dam, levee,
tank, basin, berm, or diversion ridge.
The probability or chance that a given storm event/flood
will be equaled or exceeded in a given year.
A slope, usually of a road, channel or natural ground, specified
in percent and shown on plans as specified herein.
A natural or constructed waterway, usually broad and shallow,
covered with erosion-resistant grasses, used to conduct surface water
from cropland.
The replenishment of existing natural underground water supplies.
The classification of soils according to their runoff-producing
characteristics by NRCS. 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.
A surface that prevents the infiltration of water into the
ground. Impervious surfaces (or areas) shall include, but are not
limited to, roofs, additional indoor living spaces, patios, garages,
storage sheds and similar structures, and any new streets and sidewalks.
Any surface area proposed to initially be gravel or crushed stone
shall be assumed to be impervious, unless designed and maintained
as an infiltration BMP. Decks, parking areas, and driveway areas are
not counted as impervious areas if they do not prevent infiltration.
A retention or detention basin designed to retain stormwater
runoff and release it at a controlled rate.
A structure designed to direct runoff into the ground (e.g.,
french drains, seepage pits, infiltration trench, rain gardens, etc.).
A surface connection to a closed drain. A structure at the
diversion end of a conduit. The upstream end of any structure through
which water may flow.
Plants which grow quickly and aggressively, spreading, and
displacing other plants. Invasives typically are introduced into a
region far from their native habitat. See Invasive Plants in Pennsylvania
by the Department of Conservation and Natural Resources.
A type of topography or landscape characterized by features
including but not limited to surface depressions, sinkholes, rock
pinnacles/uneven bedrock surface, underground drainage, and caves.
Karst is formed on carbonate rocks, such as limestone or dolomite.
Any activities meeting the definition of land development
in the Township Subdivision and Land Development Ordinance.[4]
Any activity involving grading, tilling, digging, or filling
of ground or stripping of vegetation or any other activity that causes
an alteration to the natural condition of the land; the erection of
a dwelling or other structure; or the modification, removal, filling,
or alteration of an existing stormwater management facility or drainage
easement. Land disturbance activities shall be classified as follows:
Major land disturbance activity:
Any activity requiring the submission of a subdivision or land
development plan by the Township Subdivision and Land Development
Ordinance;
Any land disturbance not defined as a minor land disturbance
activity or deemed to qualify as a minor land disturbance activity
by the Township;
Any use involving the diversion or piping of any natural or
man-made watercourse or existing drainage pattern.
Minor land disturbance activity:
The use of land on an existing lot of record, including subdivided lots or land developments approved under a major land disturbance activity, which can be processed according to the standard procedure in § 122-35A, provided that:
The use is not within a floodplain area;
No diversion or piping of any natural or man-made water course
or existing drainage pattern is involved;
The use does not create more than 2,500 square feet of impervious
area or involves the removal of ground cover, grading, filling, or
excavation of more than 5,000 square feet, either of which shall be
measured on a cumulative basis from April 1, 2014; and
The use does not require the submission of a subdivision or
land development plan as herein defined.
In certain instances, the addition of impervious area greater than 2,500 square feet may be permitted within the Rural Agricultural Zone (R) if the alternates to stormwater management site plan processing procedures in § 122-35B are met.
Any use of the land, which in the opinion of the Township, represents
minimal ground disturbance or impact to the environment.
The legal or beneficial owner or owners of land including
the holder of an option or contract to purchase (whether or not such
option or contract is subject to any condition), a lessee if he is
authorized under the lease to exercise the rights of the landowner,
or other person having a proprietary interest in land.
A rock formation, other stratum, or soil condition which
is so slowly permeable that it effectively limits downward passage
of effluent. Seasonal high water tables, whether perched or regional,
also constitute a limiting zone.
A fracture on the order of tens of kilometers long usually
extending to the basement below sedimentary rock.
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.
Applies when the applicant demonstrates to the Township's
satisfaction that the performance standard is not achievable. The
applicant shall take into account the best available technology, cost
effectiveness, geographic features, and other competing interests
such as protection of human safety and welfare, protection of endangered
and threatened resources, and preservation of historic properties,
in making the assertion that the performance standard cannot be met
and that a different means of control is appropriate.
A conveyance or system of conveyances (including roads with
drainage systems, municipal streets, catch basins, curbs, gutters,
ditches, man-made channels, or storm drains), which is all of the
following:
Owned or operated by a state, city, town, borough, township,
county, district, association or other public body (created under
state law) having jurisdiction over disposal of sewage, industrial
wastes, stormwater or other wastes;
Designed or used for collecting or conveying stormwater;
Not a combined sewer; and
Not part of a publicly owned treatment works as defined at 40
CFR 122.2.
All separate storm sewers that are defined as "large" or
"medium" or "small" municipal separate storm sewer systems pursuant
to 40 CFR 122.26(b)(18), or designated as regulated under 40 CFR 122.26(a)(1)(v).
The Pennsylvania Municipalities Planning Code, Act of July
1, 1967, P.L. 805, No. 247, as reenacted and amended, 53 P.S. § 10101
et seq., and as may be amended in the future.
The federal government's system for issuance of permits under
the Clean Water Act, which is delegated to PADEP in Pennsylvania.
An existing channel for water runoff that was formed by natural
forces.
Ground cover which mimics the infiltration characteristics
of predominant hydrologic soil group found at the site.
Previously Soil Conservation Service (SCS) or any agency
successor to the NRCS.
Precipitation-Frequency Atlas of the United States, Atlas
14, Volume 2, United States Department of Commerce, National Oceanic
and Atmospheric Administration, National Weather Service, Hydrometeorological
Design Studies Center, Silver Spring, Maryland (2004). NOAA's Atlas
14 can be accessed at Internet address: http://hdsc.nws.noaa.gov/hdsc/pfds/.
A stormwater management element in which stormwater flows
with an open surface. Open channels include, but shall not be limited
to, natural and man-made drainageways, swales, streams, ditches, canals,
and pipes flowing partly full.
|
Point where water flows from a conduit, stream, or drain.
| |
|
"Point source" as described in 40 CFR 122.2 at the point where
the municipal separate storm sewer system discharges to surface waters
of this commonwealth.
|
Points of water disposal from a stream, river, lake, tidewater
or artificial drain.
PA. CODE CHAPTER 10225 Pa. Code § 102.1 et seq., Erosion and Sediment Control.
PA. CODE CHAPTER 10525 Pa. Code § 105.1 et seq., Dam Safety and Waterway Management.
PA. CODE CHAPTER 10625 Pa. Code § 106.1 et seq., Floodplain Management.
All contiguous land held in single and separate ownership,
regardless of whether such land is divided into one or more lots,
parcels, purparts or tracts; such land was acquired by the landowner
at different times or by different deeds, devise, partition or otherwise;
or such land is bisected by public or private streets or rights-of-way,
which was held by the landowner or his/her predecessor in title on
the effective date of this chapter. Single and separate ownership
is the ownership of property by any person, partnership, or corporation,
in which ownership is separate and distinct from that of any adjoining
property.
The maximum rate of stormwater runoff from a specific storm
event.
The Pennsylvania Department of Transportation or any agency
successor thereto.
Any material/surface that allows water to pass through at
a rate equal to or greater than natural ground cover.
A culvert, closed conduit, or similar structure (including
appurtenances) that conveys stormwater.
The Planning Commission of West Hempfield Township, Lancaster
County, Pennsylvania.
The stormwater management and erosion and sediment pollution
control plans and narrative.
Water that comes in contact with any raw material, product,
by-product, or waste during any production or industrial process.
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.
Stormwater management controls used to manage the peak flows
for the purposes of channel protection and flood mitigation.
A rainfall-runoff relation used to estimate peak flow.
Where a regulated activity constitutes a subdivision or land
development, the final subdivision or land development plan which
contains the information the ordinance requires. Where a regulated
activity does not constitute a subdivision or land development, a
stormwater management site plan containing all required information
and prepared in a form acceptable to the Office of the Recorder of
Deeds for recording.
A plan to manage stormwater runoff from an area larger than
a single development site. A regional stormwater management plan could
include two adjacent parcels, an entire watershed, or some defined
area in between. Regional stormwater management plans can be prepared
for new development, or as a retrofit to manage runoff from already
developed areas.
Any earth disturbance activities or any activities that involve the alteration or development of land in a manner that may affect stormwater runoff and that are specified in § 122-5 of this chapter.
Activity involving earth disturbance subject to regulation
under 25 Pa. Code 92, PADEP Chapter 102, or the Clean Streams Law.[5]
The percentage of pre-development peak rate of runoff from
a site or subwatershed area to which the post-development peak rate
of runoff must be reduced to protect downstream areas.
A graphical representation of the release rates for a specific
area. See Appendix H.[6]
An impoundment in which stormwater is stored and not released
during the storm event. Stored water may be released from the basin
at some time after the end of the storm.
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 recur. For example, the twenty-five-year
return period rainfall would be expected to recur on the 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 vegetated area bordering perennial and intermittent streams
and wetlands, that serves as a protective filter to help protect streams
and wetlands from the impacts of adjacent land uses.
Edge of woodlands or 35 feet from the top of the streambank,
whichever is greater.
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.
Any part of precipitation that flows over the land surface.
Soils or other materials transported by surface water as
a product of erosion.
A barrier, dam, retention or detention basin located and
designed to retain rock, sand, gravel, silt, or other material transported
by water.
The placement, discharge or any other introduction of sediment
into the waters of this commonwealth occurring from the failure to
design, construct, implement or maintain control measures and control
facilities in accordance with the requirements of this chapter.
The process by which mineral or organic matter is accumulated
or deposited by the movement of water.
An area of excavated earth filled with clean loose stone
or similar coarse material, into which surface water is directed for
infiltration into the ground.
Runoff which flows over the ground surface as a thin, even
layer, not concentrated in a channel.
The agency now known as National Resource Conservation Service
(NRCS).
A method of runoff computation developed by the SCS (now
NRCS) that is based on relating soil type and land use/cover to a
runoff parameter called "curve number" (CN).
A layer of soil or soil material approximately parallel to
the land surface and differing from adjacent genetically related layers
in physical, chemical, and biological properties or characteristics
such as color, structure, texture, consistency, kinds and number of
organisms present, degree of acidity or alkalinity, etc.
A depression in the embankment of a pond or basin which is
used to pass peak discharge greater than the maximum design storm
controlled by the pond.
The regulatory requirements to protect, maintain, reclaim,
and restore water quality under Title 25 of the Pennsylvania Code,
the Clean Streams Law and the Clean Water Act.
A volume above or below ground that is available to hold
stormwater.
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.
A storm of a specific duration, intensity, and 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."
A system of pipes and/or open channels that convey intercepted
runoff and stormwater from other sources, but excludes domestic sewage
and industrial wastes.
Drainage runoff from the surface of the land resulting from
precipitation or snow or ice melt.
Act of October 4, 1978, P.L. 864, No. 167, as amended, 32
P.S. § 680.1 et seq., and as may be amended in the future.
See "BMPs."
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, road
gutters, swales, storm sewers, pipes, BMPs, and infiltration structures.
A plan, including a narrative, to ensure proper functioning of the stormwater management facilities in accordance with Article VI of this chapter.
A permit issued by West Hempfield Township after an exemption,
minor land disturbance, or alternate plan submission is unconditionally
approved.
The Countywide Act 167 Plan for Lancaster County for managing
stormwater runoff adopted by Lancaster County as required by the Act
of October 4, 1978, 32 P.S. P.L. 864, No. 167, as amended, and known
as the "Stormwater Management Act." Also, the Act 167 Watershed Stormwater
Management Plan for Little Conestoga Creek.
The plan prepared by the developer or his/her representative
indicating how stormwater runoff will be managed at the particular
site of interest according to this chapter.
Any activity meeting the definition of subdivision in the
MPC.
The smallest drainage unit of a watershed for which stormwater
management criteria have been established in the stormwater management
plan.
A low-lying stretch of land which gathers or carries surface
water runoff.
See "forest management."
The time 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.
The Township of West Hempfield, Lancaster County, Pennsylvania.
United States Department of Agriculture or any agency successor
thereto.
A stream of water, river, brook, creek, or a channel or ditch
for water, whether natural or man-made, having a defined bed and banks
with perennial or intermittent flow.
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 this commonwealth.
The entire region or area drained by a watercourse.
Those areas that are inundated or saturated by surface or
ground water 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, fens, and similar areas. The term includes
but is not limited to wetland areas listed in the State Water Plan,
the United States Forest Service Wetlands Inventory of Pennsylvania,
the Pennsylvania Coastal Zone Management Plan and a wetland area designated
by a river basin commission. This definition is used by the United
States Environmental Protection Agency (USEPA) and the United States
Army Corps of Engineers (USACOE).
[1]
Editor's Note: See 32 P.S. § 680.1 et seq.
[5]
Editor's Note: See 35 P.S. § 691.1.
[6]
Editor's Note: Appendix H is included as an attachment to this chapter.
