For the purpose of this chapter, the following definitions shall apply unless the context clearly indicates or requires a different meaning.
ACT. The Stormwater Management Act (Act of October 4, 1978, P.L. 864 No. 167; 32 P.S. §§ 680.1 through 680.17, as amended by Act of May 24, 1984, No. 63).
APPLICANT. A landowner or developer who has filed an application for development including his or her heirs, successors and assigns.
BOROUGH. Borough of North Braddock.
CHANNEL. A perceptible natural or artificial waterway which periodically or continuously contains moving water or which forms a connecting link between two bodies of water. It has a definite bed and banks which confine the water.
CONSERVATION DISTRICT. The Allegheny County Conservation District (Westmoreland County Conservation District).
CULVERT. A closed conduit for the free passage of surface drainage under a highway, railroad, canal or other embankment.
DESIGN CRITERIA.
(1) Engineering guidelines specifying construction details and materials.
(2) Objectives, results or limits which must be met by a facility, structure or process in performance of its intended functions.
DESIGN STORM. See STORM FREQUENCY.
DETENTION. 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 in a detention basin or within the drainage system.
DETENTION POND. A pond or reservoir; usually small, constructed to impound or retard surface runoff temporarily.
DEVELOPER. The person, persons or any corporation, partnership, association or other entity or any responsible person therein or agent therefor that undertakes the activities associated with changes in land use. The term DEVELOPER is intended to include, but not necessarily be limited to, the term SUBDIVIDER, OWNER and BUILDER even though the individuals involved in successive stages of a project may vary.
DEVELOPMENT. Any activity, construction, alteration, change in land use or practice that affects stormwater runoff characteristics.
DISCHARGE. The flow or rate of flow from a canal, conduit, channel or other hydraulic structure.
DRAINAGE. In general, the removal of surface water from a given area. Commonly applied to surface water and ground water.
DRAINAGE AREA.
(1) The area of a drainage basin or watershed, expressed in acres, square miles or other unit of area. Also called CATCHMENT AREA, WATERSHED, RIVER BASIN.
(2) The area served by a sewer system receiving storm and surface water, or by a watercourse.
ENCROACHMENT. Any structure or activity which in any manner changes, expands or diminishes, the course, current or cross-section of any watercourse, floodway or body of water.
EROSION. Wearing away of the lands by running water, winds and waves.
EROSION CONTROL. The application of measures to reduce erosion of land surfaces.
GROUND COVER. Materials covering the ground surface.
GROUND WATER. Subsurface water occupying the saturation zone, from which wells and springs are fed.
GROUND WATER RECHARGE. Replenishment of ground water naturally by precipitation or runoff or artificially by spreading or injection.
IMPERVIOUS. Not allowing or allowing only with great difficulty the movement of water, impermeable.
INFILTRATION.
(1) The flow or movement of water through the interstices or pares of a soil or other porous medium.
(2) The absorption of liquid by the soil.
LAND DEVELOPMENT. Any of the following activities:
(1) The improvement of one lot or two or more contiguous lots, tracts or parcels or land for any purpose involving:
(a) 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; and/or
(b) The division or allocation of land or space, whether initially or cumulatively, between or among two or more existing or prospective occupants by means or, for the purpose of streets, common areas, leaseholds, condominiums, building groups or other feature.
(2) A subdivision of land.
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.
MAINTENANCE. The upkeep necessary for efficient operation of physical properties.
NATURAL STORMWATER RUNOFF REGIME. A watershed where natural surface configurations, runoff characteristics and defined drainage conveyances have attained the conditions of equilibrium.
OUTFALL.
(1) The point, location or structure where drainage discharges from a sewer, drain or other conduit.
(2) The conduit leading to the ultimate discharge point.
OUTLET CONTROL STRUCTURE. The means of controlling the relationship between the headwater elevation and the discharge, placed at the outlet or downstream end of any structure through which water may flow.
PEAK FLOW. Maximum flow.
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.
PENNSYLVANIA DEP. Pennsylvania Department of Environmental Protection.
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.
RETENTION POND. A basin, usually enclosed by artificial dikes, that is used to retard stormwater runoff by temporarily storing the runoff and releasing it at a predetermined rate.
RETURN PERIOD. The average interval in years over which an event of a given magnitude can be expected to recur.
RUNOFF. The 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 human-made landscape alterations.
SCS. U.S. Department of Agriculture Soil Conservation Service.
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.
STORAGE FACILITY. See DETENTION POND and RETENTION POND.
STORM FREQUENCY. The average interval in years over which a storm event of a given precipitation volume can be expected to occur.
STORM SEWER. A sewer that carries intercepted surface runoff, street water and other drainage but excludes domestic sewage and industrial waste.
STORMWATER. The portion of precipitation which runs over the land.
STORMWATER COLLECTION SYSTEM. Natural or human-made 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 PLAN. The plan for managing stormwater runoff adopted by Allegheny County and Westmoreland County as required by the Stormwater Management Act (32 P.S. §§ 680.1 et seq.)
SWALE. A low-lying stretch of land which gathers or carries surface water runoff.
WATERCOURSE. Any channel for conveyance of surface water having a defined bed and banks, whether natural or artificial, with perennial or intermittent flow.
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 stormwater runoff throughout a designated watershed adopted by Allegheny County and Westmoreland County as required by the Pennsylvania Stormwater Management Act (32 P.S. §§ 680.1 et seq.)
(Ord. 980, passed 3-16-1993; Ord. 991, passed 2-21-1995)