For the purpose 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 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, occupied or maintained".
For the purposes of this chapter, these terms shall be defined
as follows:
The removal of the surface of the land through the combined
action of human activity and natural processes at a rate greater than
would occur because of the natural process alone.
The Storm Water Management Act (Act of October 4, 1978, P.L.
864, No. 167; 32 P.S. §§ 680.1 to 680.17, as amended
by Act of May 24, 1984, No. 63).
Activities associated with agriculture such as agricultural
cultivation, agricultural operation, and animal heavy use areas. This
includes the work of producing crops, 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.
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;
changing of surface conditions by causing the surface to be more or
less impervious; land disturbance.
A landowner or developer, as defined by this chapter, who
has filed an application for development, including his/her heirs,
successors and assigns.
Activities, facilities, designs, measures or procedures used
to manage stormwater impacts from regulated earth disturbance 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 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 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 natural stream that conveys water; a ditch or open channel
excavated for the flow of water.
The widening, deepening, and headward cutting of small channels
and waterways, due to erosion caused by moderate to large floods.
An underground reservoir or tank used for storing rainwater.
The Washington County Conservation District. The Washington
County Conservation District has the authority under a delegation
agreement executed with the Department of Environmental Protection
to administer and enforce all or a portion of the regulations promulgated
under 25 Pa. Code Chapter 102.
A structure with appurtenant works that carries a stream
and/or stormwater runoff 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 agent of this Peters Township and/or agent of the governing
body involved with the administration, review or enforcement of any
provisions of this chapter by contract or memorandum of understanding.
The magnitude of precipitation from a storm event measured
in probability of occurrence (e.g., twenty-five-year storm) and duration
(e.g., twenty-four-hour), and used in computing stormwater management
control systems.
The slowing, dampening, or attenuating of runoff flows entering
the natural drainage pattern or storm drainage system by temporarily
holding water on a surface area such as detention basins, reservoirs,
on roof tops, in streets, parking lots, or within the drainage system
itself, and releasing the water at a desired rate of discharge.
A facility designed to attenuate peak stormwater runoff by
storing and releasing the runoff at a predetermined rate. A detention
facility is designed to drain completely after a rainfall event.
The volume of runoff that is captured and released into waters
of the 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.
Any activity, construction, alteration, change in land use
or similar action that affects stormwater runoff characteristics.
A lot, parcel or tract of land on which development is taking
place or is proposed.
Rate of flow, specifically fluid flow. A volume of fluid
flowing from a conduit or channel, or being released from detention
storage, per unit of time. Commonly expressed as cubic feet per second
(cfs), million gallons per day (mgd), gallons per minute (gpm), or
cubic meters per second (cms).
An unstabilized land area where an earth disturbance activity
is occurring or has occurred.
That portion of the property line of the lot, tract, or parcels
of land being developed located such that all overland or pipe flow
from the site would be directed toward it.
Interception and removal of excess surface water or groundwater
from land by artificial or natural means.
The contributing area to a single drainage basin, expressed
in acres, square miles, or other units of area; also called a catchment
area, watershed, or river basin; the area served by a drainage system
or by a watercourse receiving stormwater and surface water.
The area from which water is carried off by a drainage system;
a watershed or catchment area.
A stormwater management facility designed to convey stormwater
runoff and shall include streams, channels, swales, pipes, conduits,
culverts, storm sewers, etc.
A right granted by a landowner to a grantee allowing the
use of private land for stormwater management purposes.
Any natural or artificial watercourse, trench, ditch, pipe,
swale, channel, or similar depression into which surface water flows.
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 and tilling, timber harvesting, road maintenance, mineral
extraction, building construction and the moving, depositing, stockpiling,
or storing of soil, rock or earth materials.
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.
Surface waters of high quality, which satisfies Pa. Code
Title 25, Environmental Protection, Chapter 93, Water Quality Standards,
§ 93.4b(b) (relating to anti-degradation).
The initial condition of a project site prior to the proposed
construction. If the initial condition of the site is undeveloped
land and not forested, the land use shall be considered as "meadow"
unless the natural land cover is documented to generate lower curve
numbers or Rational "C" Coefficient.
The Federal Emergency Management Agency.
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 the commonwealth.
The remaining portions of the one-hundred-year floodplain
outside of the floodway boundary.
Any land area susceptible to inundation by water from any
natural source or delineated by applicable Department of Housing and
Urban Development, Federal Insurance Administration Flood Hazard Boundary
mapped as being a special flood hazard area. Included are lands adjoining
a river or stream that have been or may be inundated by a one-hundred-year
flood. Also included are areas that comprise Group 13 Soils, as listed
in Appendix A of the Pennsylvania Department of Environmental Protection
(PADEP) Technical Manual for Sewage Enforcement Officers (as amended
or replaced from time to time by PADEP). For regulatory purposes,
the Pennsylvania Flood Plain Management Act (Act of October 4, 1978,
P.L. 851, No. 166)[1] and regulations pursuant to the Act define the floodplain
as the area inundated by a one-hundred-year flood and delineated on
a map by FEMA (Federal Emergency Management Agency) or by the applicant
in accordance with municipal ordinance requirements.
The channel of the watercourse and those portions of the
adjoining floodplains that 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 landward from the top of the bank of the
stream.
Planning and 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, site preparation and reforestation.
Measurement from a water surface elevation to the top of
a detention/retention facility.
A slope, usually of a road, channel or natural ground specified
in percent and shown on plans as specified herein.
To finish the surface of a roadbed, top of embankment or
bottom of excavation.
Replenishment of existing natural underground water supplies.
(Hydrologic Engineering Center Hydrologic Modeling System)
A computer-based hydrologic modeling technique adapted to the watershed(s)
in Washington County for the Act 167 Plan. The model has been calibrated
by adjusting key model input parameters.
Computer model developed by the Army Corps of Engineers to
predict flood hydrographs.
Surface water having quality, which exceeds levels necessary
to support propagation of fish, shellfish, and wildlife and recreation
in and on the water by satisfying Pa. Code Title 25, Environmental
Protection, Chapter 93, Water Quality Standards, § 93.4b(a).
The branch of science concerned with the mechanics of fluids,
especially liquids. As applied in stormwater management, the study
of the characteristics of water flow in, and conveyance capacity of,
a watercourse, considering such factors as depth, velocity and turbulence.
Infiltration rates of soils vary widely and are affected
by subsurface permeability as well as surface intake rates. Soils
are classified into one of four HSG (A, B, C, and D) according to
their minimum infiltration rate, which is obtained for bare soil after
prolonged wetting. The Natural Resource Conservation Service (NRCS)
of the United States Department of Agriculture 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 interest may
be identified from a soil survey report from the local NRCS office
or the County Conservation District.
The science dealing with waters of the earth and their distribution
and circulation through the atmosphere. Engineering hydrology deals
with the application of hydrologic concepts to the design of projects
for use and control of water.
Surface water segment found not attaining any one of the
defined uses and is included on the Stream Integrated List represents
stream assessments in an integrated format for the Clean Water Act
§ 303(d) listing.[2]
A surface that prevents the infiltration of water into the
ground. Impervious surface (or areas) include, but is not limited
to, roofs, additional indoor living spaces, patios, garages, storage
sheds and similar structures, parking or driveway areas, and any new
streets and sidewalks. Any surface areas proposed to initially be
gravel or crushed stone shall be assumed to be impervious surfaces.
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, seepage trench, 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.
A type of topography or landscape characterized by surface
depressions, sinkholes, rock pinnacles/uneven bedrock surface, steep-sided
hills, underground drainage and caves. Karst is formed on carbonate
rocks, such as limestone or dolomites and sometimes gypsum.
Any activity involving grading, tilling, digging or filling
or stripping of vegetation; or any other activity which causes land
to be exposed to the danger of erosion or changed water flow characteristics.
An approach to land development that uses various land planning
and design practices and technologies to simultaneously conserve and
protect natural resource systems and reduce infrastructure costs.
LID still allows land to be developed, but in a cost-effective manner
that helps mitigate potential environmental impacts.
Any stream segment or other runoff conveyance facility used
as a reach in the Washington County Act 167 watershed hydrologic model(s).
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.
The federal government's system for issuance of permits
under the Clean Water Act,[4] which is delegated to PADEP in Pennsylvania.
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/
Pollution that enters a water body from diffuse origins in
the watershed and does not result from discernible, confined, or discrete
conveyances.
Natural Resource Conservation Service [previously Soil Conservation
Service (SCS)].
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, canals, and pipes
not under pressure.
Points or areas at which stormwater runoff leaves a site, which
may include streams, storm sewers, swales or other well-defined natural
or artificial drainage features, as well as areas of dispersed overland
flows.
"Point source" as described in 40 CFR 122.2 at the point where
Peters Township's storm sewer system discharges to surface waters
of the commonwealth.
Points of water disposal from a stream, river, lake, tidewater,
or artificial drain.
A structure designed to control the volume of stormwater
runoff that passes through it during a specific length of time.
Pennsylvania Department of Environmental Protection.
Involves the use of impervious parking areas as temporary
impoundments with controlled release rates during rainstorms.
The maximum rate of stormwater runoff from a specific storm
event.
The maximum rate of flow of water at a given point and time
resulting from a predetermined storm.
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.
Any area not defined as impervious. (See "impervious surface.")
Material which permits the passage or entrance of water or
other liquid.
A culvert, closed conduit, or similar structure (including
appurtenances) that conveys stormwater.
The Planning Commission of Peters Township.
A point of hydraulic concern such as a bridge, culvert, or
channel section, for which the rate of runoff is computed or measured.
Usually, located at the downstream limits of a subarea.
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 by state regulations
at 25 Pa. Code § 92a.2.
The flood that may be expected from the most severe combination
of critical meteorological and hydrologic conditions that is reasonably
possible in any area. The PMF is derived from the probable maximum
precipitation (PMP) as determined on the basis of data obtained from
the National Oceanographic and Atmospheric Administration (NOAA).
The specific area of land where any regulated activities
in Peters 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.
Instantaneous measurement of water flow expressed in a unit
of volume per unit of time, also referred to as "discharge." Usually
stated in cubic feet per second (cfs) or gallons per minute (gpm).
A rainfall-runoff relation used to estimate peak flow.
Earth disturbance activities on land, which has previously
been developed.
Any earth disturbance activities or any activities that involve
the alteration or development of land in a manner that may affect
stormwater runoff.
Activity involving earth disturbance subject to regulation
under 25 Pa. Code Chapter 92a, Chapter 102, or the Clean Streams Law.
Those subwatershed areas in which post-development flows
must be reduced to a certain percentage of predevelopment flows as
required to meet the plan requirements and the goals of Act 167.
The percentage of predevelopment peak rate of runoff from
a watershed subarea (as delineated in the watershed plan), which defines
the allowable post-development peak discharge from any development
site in that subarea. The release rate percentage is determined by
computing the following ratio.
|
Subarea rate of runoff contributing to watershed peak
Subarea predevelopment peak rate of runoff
|
=
|
Release Rate Percentage
|
A facility designed to attenuate peak stormwater runoff by
retaining a portion of the runoff to create or maintain a permanent
pool of water, while releasing the remaining of runoff at a predetermined
rate.
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 given year is 0.04 (i.e., a four-percent
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.
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.
Earth disturbance activities within the existing road right-of-way,
such as grading and repairing existing unpaved road surfaces, cutting
road banks, cleaning or clearing drainage ditches, and other similar
activities. Road maintenance activities that do not disturb the subbase
of a paved road (such as milling and overlays) are not considered
earth disturbance activities.
Temporary ponding and gradual release of stormwater falling
directly onto flat roof surfaces by incorporating controlled-flow
roof drains into building designs.
Any part of precipitation that flows over the land surface.
The volume of runoff that is captured (retained) and not
released into surface waters of the commonwealth during or after a
storm event.
The surface components of any watershed which affect the
rate, amount, and direction of stormwater runoff. These may include,
but are not limited to, vegetation, soils, slopes, and man-made landscape
alterations.
Soil Conservation Service, United States Department of Agriculture
(now the NRCS).
Solid material, both mineral and organic, that is in suspension,
is being transported, or has been moved from its site or origin by
air, water, gravity, or ice and has come to rest on the earth's
surface.
A barrier, dam, retention or detention basin located and
designed to retain rock, sand, gravel, silt, or other material transported
by stormwater runoff.
The placement, discharge, or any other introduction of sediment
into waters of the commonwealth occurring from the failure to properly
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 loose stone or similar
coarse material, into which surface water is directed for infiltration
into the ground.
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.
Runoff that flows over the ground surface as a thin, even
layer, not concentrated in a channel.
A method of runoff computation developed by the Natural Resources
Conservation Service (NRCS) that is based on relating soil type and
land use/cover to a runoff parameter called "curve number (CN)."
A depression in the embankment of a pond or basin, or other
overflow structure, that is used to pass peak discharges greater than
the maximum design storm controlled by the pond or basin.
The regulatory requirements to protect, maintain, reclaim,
and restore water quality under Title 25 of the Pennsylvania Code
and the Clean Streams Law.
(See "detention basin.")
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.
The number of times that a given storm "event" occurs or
is exceeded on the average in a stated period of years. See also "return
period."
A sewer that carries intercepted surface runoff, street water,
and other wash waters, or drainage, but excludes domestic sewage and
industrial wastes.
Drainage runoff from the surface of the land resulting from
precipitation, snow, or ice melt.
Natural or engineered structures which collect and transport
stormwater through or from a drainage area to the point of final outlet,
including, but not limited to, any of the following: conduits and
appurtenant features, canals, channels, ditches, streams, culverts,
streets and pumping stations.
A land use or activity that generates higher concentrations
of hydrocarbons, trace metals, or toxicants than are found in typical
stormwater runoff.
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 Washington County Stormwater Management Plan for managing
stormwater runoff in Washington County as required by the Act of October
4, 1978, P.L. 864 (Act 167) and known as the "Storm Water Management
Act."[5]
The plan prepared by the applicant or his representative
indicating how stormwater runoff will be managed at the project site
in accordance with this chapter.
Waters resulting from snowmelt or precipitation within a
drainage basin, flowing over the surface of the ground, collected
in channels and conduits, and carried by receiving streams.
A watercourse.
A bridge, culvert, or other structure in excess of 100 feet
in length upstream to downstream which encloses a regulated waters
of the commonwealth.
A portion of the watershed that has similar hydrological
characteristics and drains to a common point.
The smallest drainage unit of a watershed for which stormwater
management criteria has been established in the stormwater management
plan.
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, 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 dwellings, shall be exempt (Pennsylvania Municipalities
Planning Code, Act of July 31, 1968, P.L. 805, No. 247[6]).
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 United States Department of Agriculture.
Quantity of water normally measured in inches, cubic feet,
or acre-feet, measured or determined analytically from:
Any channel of conveyance of surface water having a defined
bed and banks, whether natural or artificial, with perennial or intermittent
flow.
The entire region or area drained by a river or other body
of water whether natural or artificial. A "designated watershed" is
an area delineated by PADEP and approved by the Environmental Quality
Board as one for which the county is required to prepare a watershed
stormwater management plan in accordance with the Pennsylvania Storm
Water Management Act.[7]
Rivers, streams, creeks, rivulets, impoundments, ditches,
watercourses, storm sewers, lakes, dammed water, wetlands, ponds,
springs and 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 of Pennsylvania.
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, 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 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 and the United States Army Corps of Engineers.)
[1]
Editor's Note: See 32 P.S. § 679.101 et seq.
[2]
Editor's Note: See 33 U.S.C. § 1313(d).
[3]
Editor's Note: See 53 P.S. § 10503(1.1).
[4]
Editor's Note: See 33 U.S.C. § 1251 et seq,
[5]
Editor's Note: See 32 P.S. § 680.1 et seq.
[6]
Editor's Note: See 53 P.S. § 10101 et seq.
[7]
Editor's Note: See 32 P.S. § 680.1 et seq.
|
BMPs
|
Best management practices
|
|
CN
|
Curve number
|
|
E&S
|
Erosion and sedimentation
|
|
EV
|
Exceptional value
|
|
FEMA
|
Federal Emergency Management Agency
|
|
HEC-HMS
|
Hydrologic Engineering Center Hydrologic Modeling System
|
|
HQ
|
High quality
|
|
HSG
|
Hydrologic soil group
|
|
LID
|
Low-impact development
|
|
MPC
|
Pennsylvania Municipalities Planning Code, Act of July 31, 1968,
P.L. 805, No. 247[1]
|
|
MS4
|
Municipal separate storm sewer system
|
|
NPDES
|
National Pollutant Discharge Elimination System
|
|
NOAA
|
United States Department of Commerce, National Oceanic and Atmospheric
Administration
|
|
NRCS
|
Natural Resources Conservation Service
|
|
O&M
|
Operation and maintenance
|
|
PADEP
|
The Pennsylvania Department of Environmental Protection
|
|
PennDOT
|
Pennsylvania Department of Transportation
|
|
PMF
|
Probable maximum flood
|
|
SWM
|
Stormwater management
|
|
Tc
|
Time of concentration
|
|
USDA
|
United States Department of Agriculture
|
[1]
Editor's Note: See 53 P.S. § 10101 et seq.
