The language set forth in the text of this chapter shall be interpreted in accordance with the following rules of construction:
A. 
Words used or defined in one tense or form shall include other tenses or derivative forms.
B. 
Words in the singular number shall include the plural number, and words in the plural number shall include the singular number.
C. 
The masculine gender shall include the feminine and neuter. The feminine gender shall include the masculine and neuter. The neuter gender shall include the masculine and feminine.
D. 
The word "person" includes individuals, firms, partnerships, joint ventures, trusts, trustees, estates, corporations, associations and any other similar entities.
E. 
The word "lot" includes the words "plot," "tract," and "parcel."
F. 
The words "shall," "must" and "will" are mandatory in nature and establish an obligation or duty to comply with the particular provision. The words "may" and "should" are permissive.
G. 
The time within which any act required by this chapter is to be performed shall be computed by excluding the first day and including the last day. However, if the last day is a Saturday or Sunday or a holiday declared by the United States Congress or the Pennsylvania General Assembly, it shall also be excluded. The word "day" shall mean a calendar day, unless otherwise indicated.
H. 
Any words not defined in this chapter or in Section 107 of the MPC[1] shall be construed as defined in standard dictionary usage.
[1]
Editor's Note: See 53 P.S. § 10107.
I. 
References to officially adopted regulations, standards, or publications of DEP or other governmental agencies shall include the regulation, publication, or standard in effect on the date when an SWM site plan is first filed. It is the intent of the City of Lancaster in enacting this Section to incorporate such changes to statutes, regulations, and publications to the extent authorized by 1 Pa.C.S.A. § 1937.
As used in this chapter, the following terms shall have the meanings indicated:
ACCELERATED EROSION
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.
ACCESS EASEMENT
A right granted by a landowner to a grantee, allowing entry for the purpose of inspecting, maintaining and repairing SWM facilities.
ACT 167 PLAN
A plan prepared under the authority of Pennsylvania's Storm Water Management Act of October 4, 1978.[1]
AGRICULTURAL ACTIVITY
Activities associated with agriculture such as agricultural cultivation, agricultural operation, and animal heavy use areas. This includes the work of producing crops and raising livestock including tillage, land clearing, plowing, disking, harrowing, planting, harvesting crops, or pasturing and raising of livestock and installation of conservation practices. Construction of new buildings or impervious areas is not considered an agricultural activity.
ALTERATION
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; earth disturbance activity.
ANIMAL (PET) WASTE
Animal excreta and associated feed losses, bedding, litter, or other materials.
APPLICANT
A landowner and/or developer, as hereinafter defined, including his heirs, successors and assigns, who has filed an application to the City of Lancaster for approval to engage in any regulated activity at a development site located within the City of Lancaster.
BMP (BEST MANAGEMENT PRACTICE)
Activities, facilities, control measures, planning or procedures used to minimize accelerated erosion and sedimentation and manage stormwater to protect, maintain, reclaim, and restore the quality of waters and the existing and designated uses of waters within this commonwealth before, during and after earth disturbance activities. See also "nonstructural BMP" and "structural BMP."
BMP MANUAL
The Pennsylvania Stormwater Best Management Practices Manual of December 2006, or most recent version thereof.
BUILDING
Any structure which is enclosed and isolated by exterior walls and roof, built or used for residential, commercial, industrial or other public or private purposes, including accessory structures. Where the context requires, the word "building" shall be construed as if followed by the words "or part or parts thereof." For the purposes of this chapter, each portion of a structure separated from other portions by a fire wall shall be considered as a separate building. (Per Lancaster City SALDO.)[2]
CARBONATE GEOLOGY
Limestone or dolomite bedrock. Carbonate geology is often associated with karst topography.
CERTIFICATE OF COMPLETION
Documentation verifying that all permanent SWM facilities have been constructed according to the plans and specifications and approved revisions thereto.
CISTERN
A reservoir or tank for storing rainwater.
CITY
The City of Lancaster, Pennsylvania, or its designee.
CITY ENGINEER
A professional engineer registered by the Commonwealth of Pennsylvania and employed or retained by the City and designated as the City Engineer.
CLEAN WATER ACT
Amendments to the Federal Water Pollution Control Act, P.L. 92-500 of 1972, 33 U.S.C. § 1251 et seq.
COMBINED SEWER OVERFLOW
Intermittent overflow or other untreated discharge from a combined sewer system during periods of heavy precipitation or snowmelt.
COMBINED SEWER SYSTEM (CSS)
A type of sewer system that collects sanitary sewage and stormwater runoff in a single pipe system.
CONSERVATION PLAN
A plan written by an NRCS certified planner that identifies Conservation Practices and includes site-specific BMPs for agricultural plowing or tilling activities and animal heavy use areas.
CONSERVATION PRACTICES
Practices installed on agricultural lands to improve farmland, soil and/or water quality which have been identified in a current conservation plan.
CONTRIBUTORY DRAINAGE AREA
The total area that contributes runoff to a given point of discharge.
CONVEYANCE
A. 
(n) Any structure that carries a flow.
B. 
(v) The ability of a pipe, culvert, swale or similar facility to carry the peak flow from the design storm.
CULVERT
A structure with appurtenant works which can convey a stream under or through an embankment or fill.
DEP (also PA DEP or PADEP)
The Pennsylvania Department of Environmental Protection or any agency successor to the Pennsylvania Department of Environmental Protection.
DESIGN STORM
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 SWM systems.
DESIGN STORM DEPTH
The amount of rainfall, based on the Design Storm Method described in § 260-303A, that can be captured and infiltrated in a particular BMP.
DETENTION BASIN
An impoundment structure designed to manage stormwater runoff by temporarily storing the runoff and releasing it at a controlled rate.
DEVELOPER
A person, partnership, association, corporation, or other entity, including governmental or municipal agency or authority that undertakes any regulated activity of this chapter.
DEVELOPMENT SITE (SITE)
The specific area of land where regulated activities in the City of Lancaster are planned, conducted or maintained.
DIRECTOR
The Director of the Department of Public Works or her or his designee.
DISAPPEARING STREAM
A stream in an area underlain by limestone or dolomite that flows underground for a portion of its length.
DISTURBED AREA
A land area where an earth disturbance activity is occurring or has occurred.
DRAINAGE AREA
See "contributory drainage area."
DRAINAGE BASIN
A geographic and hydrologic subunit of a watershed.
DRAINAGE EASEMENT
Rights to occupy and use another person's real property for the installation and operation of stormwater management facilities, or for the maintenance of natural drainage ways to preserve and maintain a channel for the flow of stormwater therein, or to safeguard health, safety, property, and facilities.
E&S
Erosion and sediment.
E&S PLAN (also EROSION AND SEDIMENT CONTROL PLAN)
A site-specific plan consisting of both drawings and a narrative that identifies BMPs to minimize accelerated erosion and sedimentation before, during and after earth disturbance activities.
EARTH DISTURBANCE ACTIVITY
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.
ENVIRONMENTALLY SENSITIVE AREA
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 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.
EROSION
The natural process by which the surface of the land is worn away by water, wind, or chemical action. See also "accelerated erosion" as defined above.
EXISTING CONDITIONS
The dominant land cover during the five-year period immediately preceding a proposed regulated activity.
FEMA
The Federal Emergency Management Agency.
FLOOD
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.
FLOOD FRINGE
That portion of the floodplain outside of the floodway.
FLOODPLAIN — Any land area susceptible to inundation by water from any natural source or delineated by applicable Department of Homeland Security, Federal Insurance Administration Flood Hazard Boundary
Mapped as being a special flood hazard area. Also, the area of inundation that functions as a storage or holding area for floodwater to a width required to contain a base flood of which there is a 1% chance of occurrence in any given year. The floodplain contains both the floodway and the flood fringe.
FLOODPLAIN MANAGEMENT ACT
Act of October 4, 1978, P.L. 851, No. 166, as amended 32 P.S. § 679.101 et seq.
FLOODWAY
That portion of the floodplain which is effective in carrying flow, within which this carrying capacity must be preserved and where the flood hazard is generally highest, i.e., where water depths and velocities are the greatest. It is that area which provides for the discharge of the base flood so the cumulative increase in water surface elevation is no more than one foot.
FOREST MANAGEMENT/TIMBER OPERATIONS
Planning and activities necessary for the management of forest land. These include conducting a timber inventory and preparation of forest management plans, silvicultural treatment, cutting budgets, logging road design and construction, timber harvesting, site preparation and reforestation.
FREQUENCY
The probability or chance that a given storm event/flood will be equaled or exceeded in a given year.
GARDEN
A plot of ground where herbs, fruits, flowers, or vegetables are cultivated for personal use.
GRADE
A slope, usually of a road, channel or natural ground specified in percent and shown on plans as specified herein. To grade is to finish the surface of a roadbed, top of embankment or bottom of excavation.
GREEN INFRASTRUCTURE
Small-scale stormwater management practices, nonstructural techniques, and better site planning to mimic natural hydrologic runoff characteristics and minimize the impact of development on water resources.
GREEN INFRASTRUCTURE DESIGN MANUAL
A manual of policies, procedures, rules, regulations and guidelines related to the operation and implementation of the provisions of this chapter promulgated from time to time by the Director and posted on the City's publicly accessible website.
GROUNDWATER RECHARGE
The process by which water from above the ground surface is added to the saturated zone of an aquifer, either directly or indirectly.
HYDROLOGIC SOIL GROUP (HSG)
Refers to soils grouped according to their runoff-producing characteristics by NRCS. There are four runoff potential groups ranging from A to D.
A. 
(Low runoff potential) Soils having high infiltration rates even when thoroughly wetted and consisting chiefly of deep, well- to excessively drained sands or gravels. These soils have a high rate of water transmission (greater than 0.30 inch/hour).
B. 
Soils having moderate infiltration rates when thoroughly wetted and consisting chiefly of moderately deep to deep, moderately well- to well-drained soils with moderately fine to moderately coarse textures. These soils have a moderate rate of water transmission (from 0.15 to 0.30 inch/hour).
C. 
Soils having slow infiltration rates when thoroughly wetted and consisting chiefly of soils with a layer that impedes downward movement of water, or soils with moderately fine to fine texture. These soils have a slow rate of water transmission (from 0.05 to 0.15 inch/hour).
D. 
(High runoff potential) Soils having very slow infiltration rates when thoroughly wetted and consisting chiefly of clay soils with a high swelling potential, soils with a permanent high water table, soils with a clay pan or clay layer at or near the surface, and shallow soils over nearly impervious material. These soils have a very slow rate of water transmission (from 0 to 0.05 inch/hour).
IMPERVIOUS SURFACE (IMPERVIOUS AREA)
Surface which prevents or limits the infiltration of water into the ground. Any structure, building, parking area, driveway, road, street, sidewalk, patio, deck, and any area of concrete, asphalt, pavement, compacted gravel, packed stone, stone, brick, tile, swimming pool, or artificial turf, and highly compacted soil shall be considered "impervious surface" if they prevent or limit infiltration. Impervious surface also includes any area used by or for motor vehicles or heavy commercial equipment, regardless of surface type or material, including any road, road shoulder, driveway, or parking area.
IMPERVIOUS SURFACE, NEW
Any impervious surface constructed as part of a regulated activity as defined in § 260-105.
IMPOUNDMENT
A retention or detention facility designed to retain stormwater runoff and infiltrate it into the ground (in the case of a retention basin) or release it at a controlled rate (in the case of a detention basin).
INFILTRATION STRUCTURE
A structure designed to direct runoff into the ground (e.g., French drains, seepage pits, seepage trench, rain gardens, vegetated swales, pervious paving, infiltration basins, etc.).
INLET
A surface connection to a closed drain. The upstream end of any structure through which water may flow.
INTERMITTENT
A natural, transient body or conveyance of water that exists for a relatively long time, but for weeks or months of the year is below the local water table and obtains its flow from both surface runoff and groundwater discharges.
INVASIVE VEGETATION (INVASIVES)
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.
KARST
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.
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:
(1) 
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; or
(2) 
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. 
Any subdivision of land.
C. 
Development in accordance with Section 503(1.1) of the Pennsylvania Municipalities Planning Code.[3]
LAND DISTURBANCE
See "earth disturbance activity."
LANDOWNER
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.
LANDSCAPING
The planting, configuration and maintenance of any combination of trees, ground cover, shrubbery and other vegetative plant material.
LARGE PROJECT
See "project."
LIMITING ZONE
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.
LINEAMENT
A linear feature in a landscape which is an expression of an underlying geological structure such as a fault.
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 located on site.
MANNING'S EQUATION
An equation 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. Manning's Equation assumes steady, gradually varied flow.
MAXIMUM EXTENT PRACTICABLE (MEP)
Applies when the applicant demonstrates to the City of Lancaster'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.
MPC
The Pennsylvania Municipalities Planning Code, Act of 1968, P.L. 805, No. 247, as reenacted and amended, 53 P.S. § 10101 et seq.
MUNICIPAL SEPARATE STORM SEWER
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:
A. 
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;
B. 
Designed or used for collecting or conveying stormwater;
C. 
Not a combined sewer; and
D. 
Not part of a publicly owned treatment works as defined at 40 CFR § 122.2.
MUNICIPAL SEPARATE STORM SEWER SYSTEM (MS4)
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).
NATIONAL POLLUTION DISCHARGE ELIMINATION SYSTEM (NPDES)
The National system for the issuance of permits under section 402 of the Federal Clean Water Act (33 U.S.C. § 1342) including a state or interstate program which has been approved in whole or in part by the US Environmental Protection Agency (EPA), including the regulations codified in Pa. Code Chapter 92[4] (relating to National Pollutant Discharge Elimination System permitting, monitoring and compliance), and as specified in Pa. Code Chapter 102.
NATIVE VEGETATION
Plant species that has traditionally inhabited or naturally occurred in the Mid-Atlantic Region; not been introduced to the Mid-Atlantic Region as a result of human activity, either intentional or accidental; and has also been listed as a native in the Mid-Atlantic Region in the United States Department of Agriculture's PLANTS Database.
NATURAL DRAINAGEWAY
An existing channel for water runoff that was formed by natural processes.
NATURAL GROUND COVER
Ground cover which mimics the infiltration characteristics of predominant hydrologic soil group found at the site.
NON-STRUCTURAL BMPs
Planning and design approaches, operational and/or behavior-related practices which minimize stormwater runoff generation resulting from an alteration of the land surface or limit contact of pollutants with stormwater runoff.
NONPOINT SOURCE POLLUTION
Any source of water pollution that does not meet the legal definition of "point source" in Section 502(14) of the Clean Water Act.[5]
NRCS
USDA Natural Resources Conservation Service (previously Soil Conservation Service, or SCS).
OPEN CHANNEL
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 flowing partly full. Open channels may include closed conduits so long as the flow is not under pressure.
OUTFALL
Point where water flows from a conduit, stream, pipe, or drain.
PA. CODE CHAPTER 102
25 Pa. Code, Chapter 102, Erosion and Sediment Control
PA. CODE CHAPTER 105 25 Pa. Code, Chapter 105, Dam Safety and Waterway Management
PA. CODE CHAPTER 106
25 Pa. Code, Chapter 106, Floodplain Management
OVERFLOW EVENT
See "combined sewer overflow."
PAVEMENT RECONSTRUCTION
The replacement of the entire existing pavement depth by the placement of a similar, equivalent, increased or alternative pavement structure. Reconstruction involves removing and replacing all or part of the asphalt, concrete, or paver surface and aggregate base.
PEAK DISCHARGE
The maximum rate of stormwater runoff from a specific storm event.
PennDOT
The Pennsylvania Department of Transportation or any agency successor thereto.
PERVIOUS AREA (PERMEABLE OR POROUS SURFACE)
Any material/surface that allows water to pass through at a rate equal to or greater than natural ground cover.
PIPE
A culvert, closed conduit, or similar structure (including appurtenances) that conveys stormwater.
PLANNING COMMISSION
The Planning Commission of The City of Lancaster, Lancaster County, Pennsylvania.
PLANS
The SWM and erosion and sediment control plans and narratives.
PROCESS WASTEWATER
Water that comes in contact with any raw material, product, by-product, or waste during any production or industrial process.
PROJECT
Any regulated activity requiring review under this chapter.
A. 
LARGE PROJECTRegulated activities that create additional impervious area equal to or greater than 1,000 square feet or involve removal of ground cover, grading, filling or excavation of an area equal to or greater than 5,000 square feet.
B. 
SMALL PROJECTRegulated activities that, measured on a cumulative basis, create additional impervious areas of less than 1,000 square feet or involve removal of ground cover, grading, filling or excavation of an area less than 5,000 square feet and do not involve the alteration of stormwater facilities or watercourses.
C. 
VERY SMALL PROJECTRegulated activities that have negligible impervious coverage of less than or equal to 100 square feet measured in aggregate. Very small projects may include pads for trash receptacles, walkways, small patios and other nonvegetative landscape elements. Fence posts, tombstones, mailboxes, doghouses, portable outdoor grills, and lawn ornaments generally do not require permits.
PROJECT SITE
The specific area of land where any regulated activities in the City are planned, conducted, or maintained.
QUALIFIED PERSON
Any person licensed by the Pennsylvania Department of State or otherwise qualified by law to perform the work required by this chapter.
RATE CONTROL
SWM controls used to manage the peak flows for the purposes of channel protection and flood mitigation.
RATIONAL METHOD (RATIONAL FORMULA)
A rainfall-runoff relation used to estimate peak flow.
REDEVELOPMENT
Any physical improvement to a previously developed lot that involves earthmoving, removal, or addition of impervious surfaces.
REGIONAL STORMWATER MANAGEMENT PLAN
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.
REGULATED ACTIVITIES
Activities, including earth disturbance activities that involve the alteration or development of land in a manner that may affect stormwater runoff. Regulated activities shall include, but not be limited to:
A. 
Land development subject to the requirements of the City of Lancaster Subdivision and Land Development Ordinance;[6]
B. 
Removal of ground cover, grading, filling or excavation; replacing existing impervious surface with new (reconstructed) impervious surface such as repairs to parking lots, that require disturbing the stone base of the parking lot;
C. 
Construction of new or reconstruction of existing impervious or semi-impervious surfaces (driveways, parking lots, etc.), and associated improvements;
D. 
Construction of new buildings or additions to existing buildings;
E. 
Installation or alteration of stormwater management facilities and appurtenances thereto;
F. 
Diversion or piping of any watercourse;
G. 
Demolition or razing of all or a portion of an existing structure; and,
H. 
Any other regulated activities where the City of Lancaster determines that said activities may affect any existing watercourse's stormwater management facilities, or stormwater drainage patterns.
RELEASE RATE
For a specific design storm or list of design storms, the percentage of peak flow rate for existing conditions which may not be exceeded for the proposed conditions.
RELEASE RATE MAP
A graphical representation of the release rates for a specific area.
RETENTION BASIN
A stormwater management facility that includes a permanent pool for water quality treatment and additional capacity above the permanent pool for temporary runoff storage.
RIPARIAN
Pertaining to a stream, river or other watercourse. Also, plant communities occurring in association with any spring, lake, river, stream or creek through which waters flow at least periodically.
RIPARIAN BUFFER
A BMP that is an area of permanent vegetation along a watercourse.
RIPARIAN CORRIDOR
A narrow strip of land, centered on a stream or river that includes the floodplain as well as related riparian habitats adjacent to the floodplain.
RIPARIAN CORRIDOR EASEMENT
An easement created for the purpose of protecting and preserving a riparian corridor.
RIPARIAN FOREST BUFFER
A type of riparian buffer that consists of permanent vegetation that is predominantly native trees, shrubs and forbs along a watercourse that is maintained in a natural state or sustainably managed to protect and enhance water quality, stabilize stream channels and banks, and separate land use activities from surface waters.
ROOFTOP DETENTION
Temporary ponding and gradual release of stormwater falling directly onto roof surfaces by incorporating controlled-flow roof drains into building designs.
RUNOFF
Any part of precipitation that flows over the land surface.
SCS
U.S. Department of Agriculture, Soil Conservation Service (now known as NRCS).
SEDIMENT
Soils or other materials transported by stormwater as a product of erosion.
SEDIMENT BASIN
A barrier, dam, retention or detention basin located and designed to retain rock, sand, gravel, silt, or other material transported by water.
SEDIMENT POLLUTION
The placement, discharge or any other introduction of sediment into the waters of the Commonwealth occurring from the failure to design, construct, implement or maintain control measures and control facilities in accordance with the requirements of this chapter.
SEDIMENTATION
The action or process of forming or depositing sediment in waters of the commonwealth.
SEEPAGE PIT/SEEPAGE TRENCH
An area of excavated earth filled with loose stone or similar coarse material, into which surface water is directed for infiltration into the ground.
SEMI-IMPERVIOUS/SEMI-PERVIOUS SURFACE
A surface which prevents some infiltration of water into the ground.
SEWERSHED
A defined area of land, or catchment, which drains to a common point.
SHEET FLOW
Runoff which flows over the ground surface as a thin, even layer, not concentrated in a channel.
SMALL PROJECT
See "project."
SMALL STORM EVENT
A storm having a frequency of recurrence of once every two years or smaller.
SOIL GROUP, HYDROLOGIC
See "hydrologic soil group."
SOIL-COVER COMPLEX METHOD
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). For more information, see "Urban Hydrology for Small Watersheds", Second edition, Technical Release No. 55, SCS, June 1986 (or most current edition).
SPEC MANUAL
The Lancaster City Specifications and Guidelines Manual.
STATE WATER QUALITY REQUIREMENTS
The regulatory requirements to protect, maintain, reclaim, and restore water quality under Title 25 of the Pennsylvania Code, the Clean Streams Law[7] and the Clean Water Act.[8]
STORAGE
A volume above or below ground that is available to hold stormwater.
STORM EVENT
A storm of a specific duration, intensity, and frequency.
STORM SEWER
A system of pipes and/or open channels designed to convey stormwater.
STORMWATER
Drainage runoff from the surface of the land resulting from precipitation or snow or ice melt.
STORMWATER CREDIT (NONSTRUCTURAL)
A reduction in stormwater management requirements necessary to meet the City's SWM Ordinance through to the use of non-structural BMPs to minimize and/or manage stormwater runoff. See § 260-305H(3) of this chapter and the latest edition of the City's GI Design Manual for more information. Note that this is different than a stormwater management fee credit.
STORMWATER MANAGEMENT ACT (ACT 167)
Act of October 4, 1978, P.L. 864, No. 167, as amended 32 P.S. § 680.1 et seq. This stormwater act shall also be referred to herein as Act 167.
STORMWATER MANAGEMENT BEST MANAGEMENT PRACTICES (SWM BMP)
See "BMPs."
STORMWATER MANAGEMENT FACILITY (SWM FACILITY)
Any structure, natural or man-made, that, due to its condition, design, or construction, conveys, stores, infiltrates/evaporates/transpires, cleans or otherwise affects stormwater runoff. Typical SWM facilities include, but are not limited to, detention and retention basins, open channels, watercourses, road gutters, swales, storm sewers, pipes, BMPs, and infiltration structures.
STORMWATER MANAGEMENT OPERATION AND MAINTENANCE PLAN (O & M PLAN)
A plan, including a narrative, to ensure proper functioning of the SWM facilities in accordance with Article VI of this chapter.
STORMWATER MANAGEMENT SITE PLAN (SWM SITE PLAN)
The Plan prepared by the applicant or his representative indicating how stormwater runoff will be managed at a particular development site according to this chapter.
STREAM
A watercourse.
STRUCTURAL BMPS
Physical devices and practices that capture and treat stormwater runoff. Structural stormwater BMPs are permanent appurtenances to the development site.
STRUCTURE
Any man-made object having an ascertainable stationary location on or in land or water, whether or not affixed to the land.
SUBDIVISION
The division or re-division of a single 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, partition by the court for distribution to heirs or devises, transfer of ownership, or building, or land development or as defined in the MPC.[9]
SWALE
A low lying stretch of land which gathers or carries surface water runoff.
SWM
Stormwater management.
SWM SITE PLAN
A Stormwater management site plan.
TIMBER OPERATIONS
See "forest management."
TIME OF CONCENTRATION (Tc)
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, or the time needed for water to flow from the most remote point in a watershed to the watershed outlet.
TOP OF STREAM BANK
First substantial break in slope between the edge of the bed of the stream and the surrounding terrain. The top of stream bank can either be a natural or constructed (that is, road or railroad grade) feature, lying generally parallel to the watercourse.
TREATMENT TRAIN
The sequencing of structural best management practices to achieve optimal flow management and pollutant removal from urban stormwater.
TREE MANUAL
A supplement to Lancaster Trees Ordinance, Chapter 273, that outlines requirements for the planting of trees, the care and maintenance of existing trees, tree protection, and the preservation of trees within the City of Lancaster.
USDA
United States Department of Agriculture.
VERY SMALL PROJECT
See "project."
VOLUME CONTROL
SWM controls, or BMPs, used to remove a predetermined amount of runoff or the increase in volume between the pre- and postdevelopment design storm.
WATERCOURSE
A channel or conveyance of surface water 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 and underground water, or parts thereof, whether natural or artificial, within or on the boundaries of Pennsylvania.
WATERSHED
The entire region or area drained by a watercourse.
WETLAND
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.
WOODLAND
Land predominantly covered with trees and shrubs. Without limiting the foregoing, Woodlands include all land areas of 10,000 square feet or greater, supporting at least 100 trees per acre, so that either:
A. 
At least 50 trees are two inches or greater in diameter at breast height (DBH), or
B. 
Fifty trees are at least 12 feet in height.
[1]
Editor's Note: See 32 P.S. § 680.1 et seq.
[2]
Editor's Note: See Ch. 265, Subdivision and Land Development.
[3]
Editor's Note: See 53 P.S. § 10503(1.1).
[4]
Editor's Note: Former 25 Pa. Code Ch. 92 was repealed effective 10-9-2010. See now 25 Pa. Code Ch. 92A.
[5]
Editor's Note: See 33 U.S.C. § 1362(4).
[6]
Editor's Note: See Ch. 265, Subdivision and Land Development.
[7]
Editor's Note: See 35 P.S. § 691.1 et seq.
[8]
Editor's Note: See 33 U.S.C. § 1251 et seq.
[9]
Editor's Note: See 53 P.S. § 10101 et seq.