"'f Hot spots - Areas where land use or acuvities generate highly contaminated runoff, with
concentrations of pollutants that are higher than those typically found in stormwater (e.g., vehicle
salvage yards and recycling facilities, vehicle fueling stations, fleet storage areas, vehicle
equipment and cleaning facilities, vehicle service and maintenance facilities, and certain
industrial/commercial activity areas).
Hydrologic Soil Group (HSG) - 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 permeable as the HSG varies from A to D
Impervious surface - a surface that prevents the infiltration of water into the ground. Impervious
surfaces (or areas) shall include, but not be limited to: roofs, additional indoor living spaces, patios,
garages, storage sheds, and similar structures; and any new streets or sidewalks. Decks, parking
areas, gravel areas, and driveway areas are counted as impervious areas if they directly prevent
infil trati on.
Infiltration - any of the following activities:
(a) The flow or movement of water through the interstices or pores of a soil or other porous
(b) The absorption ofliquid by the soil.
Land development - any of the following activities:
(a) The improvement of one lot or two or more contiguous lots, tracts or parcels of land for
any purpose involving:
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.
11 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.
(b) A subdivision ofland.
Land disturbance - any activity involving the changing, grading, transportation, fill and any
other activity which causes land to be exposed to the danger of erosion.
Low Impact Development (LID) - 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
Maintenance - the upkeep necessary for efficient operation of physical properties.
MS4 (municipal separate storm sewer system) - A conveyance or system of conveyances
(including roads with drainage systems, municipal streets, catch basins, curbs, gutters, ditches,
man-made channels, or storm drains):
(a) Owned or operated by a State, city, town, borough, county, parish, district,
association, or other public body (created by or pursuant to State law) . .including special
districts under State law such as a sewer district, flood control district or drainage district,
or similar entity, or an Indian tribe or an authorized Indian tribal organization, or a
designated and approved management agency under section 208 of the Clean Water Act
that discharges into waters of the United States.
(b) Designed or used for collecting or conveying storm water;
(c) Which is not a combined sewer; and
(d) Which is not part of a Publicly Owned Treatment Works (POTW) as defined at 40 CFR
Municipalities Planning Code- Act 247 of 1968, as amended by Act 170 of 1988,53 P.S. §10101
Municipality - Bolivar Borough, Westmoreland County, Pennsylvania.
Native Vegetation - Plant species that have historically grown in Pennsylvania and are not
invasive species, controlled plants or noxious weeds as defined by PA DCNR, or P A Department
Natural stormwater runoff regime - a watershed where natural surface configurations, runoff
characteristics and defined drainage conveyances have attained the conditions of equilibrium.
NPDES - 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.
NRCS - Natural Resources Conservation Service (previously Soil Conservation Service).
Outfall- "point source" as described in 40 CFR § 122.2 at the point where Bolivar Borough storm
sewer system discharges to surface waters of the Commonwealth. Also, the point, location or
structure where drainage discharges from a sewer, drain or other conduit as well as the conduit
leading to the ultimate discharge point.
Outlet control structure - the means of controlling the relationship between the head water
elevation and the discharge, placed at the outlet or downstream end of any structure through which
water may flow.
Overland flooding - flooding that occurs for a variety of reasons all stemming from excessive
stormwater runoff including too much rain in too little time, added impervious development,
change in land use, malfunction or clogging of existing stormwater systems.
Peak discharge - The maximum rate of stormwater runoff from a specific storm event.
Peak flow - maximum flow.
Pervious Area - Any material or surface that allows water to pass through at a rate equal to or
greater than natural ground cover.
Pennsylvania DEP - Pennsylvania Department of Environmental Protection.
Performance standard - a standard which establishes an end result or outcome which is to be
achieved but does not prescribe specific means for achieving it.
Person - an individual, partnership, public or private association or corporation, firm, trust, estate,
municipality, governmental unit, public utility or any other legal entity whatsoever which is
recognized by law as the subject of rights and duties. Whenever used in any section prescribing
or imposing a penalty, the term "person" shall include the members of a partnership, the officers,
members, servants and agents of an association, officers, agents and servants of a corporation, and
the officers of a municipality or county, but shall exclude any department, board, bureau or agency
of the Commonwealth.
Point source - 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.
Project site - the specific area of land where any development or regulated earth disturbance
activities in Bolivar Borough are planned, conducted, undertaken or maintained.
Qualified Professional - Any person licensed by the Pennsylvania Department of State or
otherwise qualified under Pennsylvania law to perform the work required by this Ordinance.
Record drawings - Drawings showing the stormwater management system of a site as built,
created after the completion of construction and intended for use as a permanent record of the
stormwater management system.
Redevelopment - earth disturbance activities on land which has previously been disturbed or
Regulated development activity - Any earth disturbance activities or any activities that involve
the change of land cover, alteration or development of land in a manner that may affect stormwater
runoff as listed in the Regulated Development Activity table. This includes earth disturbance on
any portion of, part, or during any stage of, a larger common plan of development. With regard to
road maintenance activities the term only includes activities involving [1 acre] or more or earth
disturbance. Refer to the Regulated Development Activity Table in Article III of this ordinance.
Release Rate - The percentage of existing conditions peak rate of runoff from a site or subarea to
which the proposed conditions peak rate of runoff must be reduced to protect downstream areas.
Release rate percentage - the watershed factor determined by comparing the maximum rate of
runoff from a subbasin to the contributing rate of runoff to the watershed peak rate at specific
points of interest.
Resource extraction - any activity that involves withdrawing materials from the natural
Retention basin - a pond, basin, usually enclosed by artificial dikes, that is used to retard
storm water runoff by temporarily storing the runoff and releasing it at a predetermined rate.
Retention Volume/Removed Runoff - The volume of runoff that is captured and not released
directly into the surface waters of this Commonwealth during or immediately after a storm event.
Return period - the average interval in years over which an event of a given magnitude can be
expected to recur.
Riparian Buffer - A permanent area of native vegetation including herbaceous material, shrubs
and/or trees located adjacent to streams, lakes, ponds and wetlands.
Road maintenance - 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.
Runoff-that part of precipitation which flows over the land.
Runoff characteristics - 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 manmade landscape alterations.
SALDO - Subdivision and land development ordinance
Sediment - mineral or organic solid material that is being transported or has been moved from its
site of origin by air, water or ice and has come to rest.
Sedimentation - the process by which mineral or organic matter is accumulated or deposited by
moving water, wind or gravity.
Separate storm sewer system - 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. Refer to
Small project - Regulated development activities that, measured on a cumulative basis from 5
years prior to the application, create additional impervious areas of more than 1,000 square feet
and less than 3,000 square feet or involve earth disturbance activity of an area less than 5,000
square feet and do not involve the alteration of stormwater facilities or water courses.
State water quality requirements - as defined under State regulations- protection of designated
and existing uses (See 25 Pa.Code, Chapters 93 and 96)-including:
(a) Each stream segment in Pennsylvania has a "designated use," such as "cold water fishery"
or "potable water supply," which are listed in 25 Pa.Code, Chapter 93. These uses must be
protected and maintained, under State regulations.
(b) "Existing uses" are those attained as of November 1975, regardless whether they have been
designated in 25 Pa.Code, Chapter 93. Regulated earth disturbance activities must be designed
to protect and maintain existing uses and maintain the level of water quality necessary to
protect those uses in all streams, and to protect and maintain water quality in special protection
(c) Water quality involves the chemical, biological and physical characteristics of surface
water bodies. After regulated earth disturbance activities are complete, these characteristics
can be impacted by addition of pollutants such as sediment, and changes in habitat through
increased flow volumes and/or rates as a result of changes in land surface area from those
activities. Therefore, permanent discharges to surface waters must be managed to protect the
stream bank, streambed and structural integrity of the waterway, to prevent these impacts.
Storage facility - Any surface or sub-surface facility that stores stormwater runoff, see "detention
basin" and "retention basin."
Storm frequency - the average interval in years over which a storm event of a given precipitation
volume can be expected to occur. The magnitude and temporal distribution of precipitation from
a storm event measured in probability of occurrence (e.g., a 5-year storm) and duration (e.g., 24
hours) used in the design and evaluation of stormwater management systems. Also see Return
Storm sewer - a sewer that carries intercepted surface runoff, street water and other drainage but
excludes domestic sewage and industrial waste.
Stormwater - drainage runoff from the surface of the land resulting from precipitation or snow or
Stormwater collection systems - natural or manmade structures that 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.
Stormwater management facility - a constructed measure for detention, retention, infiltration and
water quality treatment of stormwater runoff.
Stormwater management plan - the plan for managing stormwater runoff rate, volume and water
quality as required by the Stormwater Management Act, 32 P.S. §680.1 et seq.
Stormwater Management Performance District - an area designated by the Watershed
Stormwater Performance District Map which includes standards for stormwater rate, volume and
water quality. Refer to Appendix A.
Subdivision - As defined in The Pennsylvania Municipalities Planning Code, Act of July 31, 1968,
P.L. 805, No. 247, as amended.
Swale - a low-lying stretch of land which gathers or carries surface water runoff.
USDA - United States Department of Agriculture.
Watercourse - a channel or conveyance of surface water, such as a run, stream or creek, having
defined bed and banks, whether natural or artificial, with perennial or intermittent flow.
Waters of the 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 water, or parts thereof, whether natural or artificial,
within or on the boundaries of this Commonwealth.
Watershed - 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 DEP and approved
by the Environmental Quality Board for which Counties are required to develop watershed
stormwater management plans.
Watershed stormwater management plan - the plan for managing storm water runoff throughout
a designated watershed as required by the Pennsylvania Stormwater Management Act (Act 167),
32 P.S. §680.1 et seq.
Wetland - 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.
Continue on next page