For the purpose of this chapter, certain terms and words used
herein shall be interpreted as follows:
A.Â
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.Â
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.Â
The word "person" includes an individual, firm, association, organization,
partnership, trust, company, corporation, or any other similar entity.
D.Â
The words "shall" and "must" are mandatory; the words "may" and "should"
are permissive.
E.Â
The words "used or occupied" include the words "intended, designed,
maintained or arranged to be used, occupied or maintained."
As used in this chapter, the following terms shall have the
meanings indicated in this section:
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.
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, developer or other person who has filed an application
for approval to engage in any regulated activities at a project site
within the municipality.
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 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.
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 Mifflin County Conservation District. The Mifflin 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 magnitude and temporal distribution of precipitation
from a storm event measured in probability of occurrence (e.g., a
twenty-five-year storm) and duration (e.g., 24 hours), used in the
design and evaluation of stormwater management systems. Also see "return
period."
The agent of this municipality 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.
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 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.
The specific tract of land for which a regulated activity
is proposed. Also see "project site."
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.
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, drainage or conveyance
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 or tilling, timber harvesting activities, road maintenance
activities, mineral extraction, 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 antidegradation).
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).
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 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.
A vertical distance between the elevation of the design high
water and the top of a dam, levee, tank, basin or diversion ridge.
The space is required as a safety margin in a pond or basin.
A slope, usually of a road, channel or natural ground, specified
in percent and shown on plans as specified herein. (TO) GRADE — 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 Mifflin County for the Act 167 Plan. The model has been calibrated
by adjusting key model input parameters.
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).
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.
A surface that prevents the infiltration of water into the
ground. Impervious surface (or areas) includes, 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.
The improvement of one lot or two or more contiguous lots, tracts
or parcels of land, whether proposed initially or cumulatively, for
any purpose involving:
A group of two or more residential or nonresidential buildings,
or a single nonresidential building on a lot or lots regardless of
the number of occupants or tenure; or
The division or allocation of land or space 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;
Any subdivision of land;
Development in accordance with Section 503(1.1) of the Pennsylvania
Municipalities Planning Code.[1]
Any stream segment or other runoff conveyance facility used
as a reach in the Mifflin 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 Borough of Lewistown, Mifflin County, Pennsylvania.
The federal government's system for issuance of permits under
the Clean Water Act, 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 of water disposal from a stream, river, lake, tidewater
or artificial drain.
The 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.
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. A surface that presents
an opportunity for precipitation to infiltrate into the ground.
A culvert, closed conduit, or similar structure (including
appurtenances) that conveys stormwater.
The Planning Commission of the Borough of Lewistown.
Any discernible, confined, or 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.[2]
The flood that may be expected from the most severe combination
of critical meteorological and hydrologic conditions that are 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).
Persons who provide expert or professional advice, including,
but not limited to, architects, attorneys, certified public accountants,
engineers, geologists, land surveyors, landscape architects or planners.
The specific area of land where any regulated activities
in the municipality 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 the
chapter.
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 92,[3] Chapter 102, or the Clean Streams Law.
The percentage of predevelopment 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.
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.
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 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.
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 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 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.
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 system of pipes and/or open channels that conveys 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, snow or ice melt.
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 Mifflin County Stormwater Management Plan for managing
stormwater runoff in Mifflin County as required by the Act of October
4, 1978, P.L. 864, (Act 167) and known as the "Storm Water Management
Act."[4]
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.
A bridge, culvert or other structure in excess of 100 feet
in length, upstream to downstream, which encloses regulated waters
of the commonwealth.
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.
A low-lying stretch of land that 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.
A channel or conveyance of surface water, such as a stream
or creek, having defined bed and banks, whether natural or artificial,
with perennial or intermittent flow.
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.
Region or area drained by a river, watercourse or other surface
water, whether natural or artificial.
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.)