[Ord. 621, 2/22/1993, § 101; as amended by Ord.
741, 12/30/2002, § 1]
This Part shall be known and may be cited as the "Borough of
Jefferson Hills Stormwater Management Ordinance" or just the "stormwater
regulations."
[Ord. No. 870, 11/12/2018]
This Part incorporates, at Appendix D, the definitions and provisions
of the Allegheny County Stormwater Management Model Ordinance, and
said definitions and provisions shall control and are the primary
means of stormwater management enforcement and planning for the Borough
of Jefferson Hills. The Borough-specific definitions and provisions
of this Part not found in the Allegheny County Stormwater Management
Model Ordinance (those discussing procedures, maintenance, inspection
and liability, calculation methodology and design criteria for conveyance
and detention facilities) are to be used as applicable in stormwater
management planning.
[Ord. 621, 2/22/1993, § 102]
This Part is adopted in accordance with the authority granted
to municipalities to regulate subdivision and land development by
the Pennsylvania Municipalities Planning Code, Act 247 of 1968, as
amended (53 P.S. § 10101 et seq.).
[Ord. 621, 2/22/1993, § 103]
These regulations are adopted and implemented to achieve the
following general purposes and objectives:
A.
To manage stormwater runoff resulting from land alteration and disturbance
activities.
B.
To utilize and protect the desirable existing natural drainage systems
and to preserve the flood protection capacity of streams.
C.
To encourage natural infiltration of rainfall to preserve groundwater
supplies and stream flows.
D.
To provide for adequate maintenance of all permanent stormwater management
facilities in the Borough.
E.
To update and revise existing Ord. 561 due to changes in the engineering
concepts concerning stormwater management.
[Ord. 621, 2/22/1993, § 104]
The provisions of this Part shall apply to all subdivision and
land developments unless specifically exempted or otherwise modified
herein.
[Ord. 621, 2/22/1993, § 105; as amended by Ord.
685, 5/11/1998]
1.
Interpretation. The word "person" includes a corporation, association,
partnership or individual. The words "shall" and "will" are mandatory;
the word "may" is permissive. The word "building" includes structure
or any part thereof. Words used in the present tense include the future
tense. Words in the masculine gender shall include the feminine gender.
2.
ACT
APPLICANT
CHANNEL
CONSERVATION DISTRICT (ACCD)
DESIGN STORM
DETENTION
DETENTION BASIN
DEVELOPMENT
DEVELOPMENT SITE
DISCHARGE
DRAINAGE
DRAINAGE AREA
DRAINAGE BASIN
DRAINAGE EASEMENT
FLOODPLAIN
HYDRAULICS
HYDROLOGY
HYDROGRAPH
IMPERVIOUS MATERIAL OR SURFACE
INTERMITTENT FLOW
LAND DISTURBANCE
OUTFALL
OUTLET STRUCTURE
PA DEP
PEAK RATE OF RUNOFF (OR DISCHARGE)
PERFORMANCE STANDARD
PERVIOUS MATERIAL
PRE-APPLICATION CONFERENCE
POINT OF INTEREST
RATE OF RUNOFF
RETENTION BASIN
RUNOFF CHARACTERISTICS
ROUTING
SCS
SEDIMENT
SOIL-COVER COMPLEX METHOD
STORAGE FACILITY
STORM SEWER
STORMWATER COLLECTION/CONVEYANCE SYSTEM
STORMWATER MANAGEMENT PLAN
STORMWATER RUNOFF
STREAM
SUBAREA
SWALE
VOLUME OF STORMWATER RUNOFF
WATERCOURSE (WATERWAY)
WATERSHED
WATER OF THIS COMMONWEALTH
Definitions. As used in this Part, the following terms shall have
the meanings indicated:
The Stormwater Management Act (Act of October 4, 1978, P.L.
864, No. 167, 32 P.S. § 680.1-690.17, as amended by Act
of May 24, 1984, No. 63).
A landowner or developer, as defined by this Part, who has
filed an application for development, including his/her heirs, successors
and assigns.
A natural stream with defined bed and banks that conveys
water; a ditch or open channel excavated for the flow of water.
The Allegheny County Conservation District.
The magnitude of precipitation from a storm event measured
in probability of recurrence (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 entering
the natural drainage pattern or storm drainage system by temporarily
holding water on a surface area such as detention basins, reservoirs,
on rooftops, in streets, parking lots, or within the drainage system
itself, and releasing the water at a desired rate of discharge.
A basin designed to retard stormwater runoff by temporarily
storing the runoff and releasing it at a predetermined rate. A detention
basin can be designed to contain a permanent pool of water, in which
case it is called a retention basin.
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, specially 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). See also "rate of runoff."
Interception and removal of excess surface water or groundwater
from land by artificial or natural means.
The contributing land 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 land area served by a drainage
system or by a watercourse receiving storm and surface water, also
called "subarea."
The land area from which water is carried off by a drainage
system; also called a "watershed" or "catchment area."
A right granted by a landowner to a grantee allowing the
use of private land for stormwater management purposes.
A normally dry land area adjacent to stream channels that
is susceptible to inundation by overbank stream flows. For regulatory
purposes, the Pennsylvania Floodplain Management Act (Act of October
4, 1978, P.L. 851, No. 166) 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 Borough ordinance requirements.
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.
The science of dealing with the 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, as well as the calculation
of the rates of stormwater runoff.
A graph showing the quantity of runoff at a specific point
in time during a rainfall event.
Material which resists the entrance or passing through of
water or other liquids. Some examples: pavement or roofs.
Flow that starts and stops again at different intervals.
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.
The points at which a storm sewer, or a natural or man-made
land drainage channel discharges to a body of water, the sea, a river
or a stream.
A structure designed to control the volume of stormwater
runoff from a detention or retention facility during a specific length
of time.
Pennsylvania Department of Environmental Protection.
The maximum rate of flow of water at a given point and time
resulting from a predetermined storm.
A standard which establishes an end result or outcome which
is to be achieved but does not prescribe specific means for achieving
it. A specification standard in contrast is one which prescribes the
exact characteristics to be used, leaving little choice to the applicant.
The allowable release rate is an example of a performance standard;
the design standards for storm sewers are specification standards.
Material which permits the passage or entrance of water or
other liquid. Examples: grass, earth, stones and trees.
A meeting with the Borough prior to a formal application
submittal.
A point of hydrologic and/or hydraulic concern such as a
bridge, culvert or channel section, for which the rate of runoff is
computed or measured.
Instantaneous measurement of water flow expressed as 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 type of detention basin designed to contain a permanent
pool of water.
The surface components of any watershed which affect the
rate, amount and direction of stormwater runoff. These may include,
but are not being limited to: vegetation, soils, slopes and man-made
landscape alterations.
Using an inflow hydrograph to simulate the water flow through
a storage facility creating storage data and an outflow hydrograph.
Soil Conservation Service, U.S. Department of Agriculture.
Solid material, both mineral and organic, that is in suspension,
is being transported, or has been removed from its site of origin
by air, water, gravity or ice and has come to rest on the earth's
surface.
A method of runoff computation developed by the U.S. Soil
Conservation Service and found in its publication "Urban Hydrology
for Small Watersheds," Technical Release No. 55, SCS (or most current
edition).
See "detention basin."
A pipe, culvert or underground open channel that carries
intercepted surface runoff, street water and other washwaters, or
drainage, but excludes domestic sewage and industrial wastes.
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.
The plan for managing stormwater runoff from a specific development
site.
Waters resulting from snow melt 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 portion of the watershed that has similar hydrological
characteristics and drains to a common point. Also called a drainage
area.
A low-lying stretch of land which gathers or carries surface
water runoff.
Quantity of water normally measured cubic feet, or acre-feet,
measured or determined analytically from (1) runoff coefficients;
(2) rainfall/runoff ratios; and (3) areas underneath hydrographs.
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 the Pennsylvania Department of Environmental
Protection 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 Stormwater Management
Act. Also called a "drainage basin."
[Amended by Ord. 844, 9/8/2014]
Rivers, streams, creeks, rivulets, impoundments, ditches,
watercourses, storm sewers, dammed water, wetlands, ponds, springs
and other bodies or channels of conveyance of surface water, or parts
thereof, whether natural or artificial, within or on the boundaries
of this commonwealth. (Source: the Clean Streams Law).
