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Unless a different meaning is clearly intended and more protective of water quality under the circumstances, terms used in this Chapter shall have the same meaning as the same or equivalent term when defined in Attachment C of California Regional Water Quality Control Board amended Order No. R9-2013-0001, NPDES No. CAS0109266. For purposes of this Chapter subject to the foregoing limitation, the following definitions shall apply:
(a) "Authorized enforcement official" means the Director of Public Works, the Director of Planning and Development Services, the Director of the Department of Environmental Health and Quality, the Director of Environmental Health, the Agricultural Commissioner, Department of Agriculture, Weights and Measures, or their designees.
(b) "Active/Passive Sediment Treatment" means using mechanical, electrical or chemical means to flocculate or coagulate suspended sediment for removal from runoff from construction sites prior to discharge.
(c) "Authorized non-stormwater discharge" means a discharge allowed to enter the stormwater conveyance system or receiving waters in accordance with a permit under the National Pollutant Discharge Elimination System or as specifically authorized by this Chapter.
(d) "Best management practices" (BMPs) shall have the same meaning as defined in the NPDES Order. Best management practices may include any type of pollution prevention and pollution control measure that achieves compliance with this Chapter.
(e) "Biofiltration" means practices that use vegetation and amended soils to detain and treat runoff from impervious areas. Treatment is through filtration, infiltration, adsorption, ion exchange, and biological uptake of pollutants.
(f) "BMP Design Manual" means the plan developed by the County in accordance with the NPDES Order to eliminate, reduce, or mitigate the impacts of water runoff from development projects and existing development.
(g) "Detention" means the temporary storage of storm run-off in a manner that controls peak discharge rates and provides some gravity settling of pollutants.
(h) "Detention facility" means a detention basin or alternative structure designed for the purpose of temporary storage of stream flow or surface run-off and gradual release of stored water at controlled rates.
(i) "Development project" means construction, rehabilitation, redevelopment, land disturbance activity, or reconstruction of any public improvement projects or private projects.
(j) "Discharge", when used as a verb, means to allow pollutants to directly or indirectly enter stormwater, or to allow stormwater or non-stormwater to directly or indirectly enter the stormwater conveyance system or receiving waters, from an activity or operations which one owns or operates. When used as a noun, "discharge" means the pollutants, stormwater, or non-stormwater that are discharged.
(k) "Discharger" means any person or entity engaged in activities or operations or owning facilities, from which an allowed non-stormwater discharge to the stormwater conveyance system may or does originate or which will or may result in pollutants entering stormwater, the stormwater conveyance system, or receiving waters or the owners of real property on which such activities, operations or facilities are located, except that a local government or public authority is not a discharger as to activities conducted by others in public rights-of-way.
(l) "Environmentally sensitive area" or "ESA" means impaired water bodies, as defined by the federal Clean Water Act, Section 303(d), areas designated as Areas of Special Biological Significance or with the RARE beneficial use by the SWRCB in the Water Quality Control Plan for the San Diego Basin (1994 and amendments) and areas designated as preserves for species- protection purposes by the State of California or a local government.
(m) "Feasible" means capable of being accomplished in a successful manner within a reasonable period of time, taking into account economic, environmental, and technological factors as determined in the sole discretion of the County. Feasibility may be limited in this Chapter to eliminate consideration of economic, environmental and other factors as, for example, where feasibility is specifically defined as technological feasibility.
(n) "Flow-thru treatment control BMPs" mean structural, engineered facilities that are designed to remove pollutants from stormwater runoff using treatment processes that do not incorporate significant biological methods. Examples include dry extended detention basins, sand filters, media filters, and vegetated swales.
(o) "Illicit connection" means any man-made conveyance or drainage system through which non-stormwater or pollutants in water, not authorized by an NPDES permit or the NPDES Order are discharged or may be discharged to the stormwater conveyance system.
(p) "Impervious surface area" means the ground area covered or sheltered by an impervious surface, measured in plan view. For example, the "impervious surface area" for a pitched roof is equal to the ground area it shelters, rather than the surface area of the roof itself.
(q) "Infiltration BMPs" mean structural measures that capture, store, and infiltrate stormwater runoff. These BMPs are engineered to store a specified volume of water and have no design surface discharge (underdrain or outlet structure) until this volume is exceeded. Infiltration BMPs may also support evapotranspiration processes, but are characterized by having their most dominant volume losses due to infiltration. They are a type of retention BMP.
(r) "Land disturbance activity" means any activity, whether or not a stormwater quality management plan or County permit or approval is required, that moves soils or substantially alters the land such as grading, digging, cutting, scraping, stockpiling or excavating of soil; placement of fill materials; paving, pavement removal, exterior construction; substantial removal of vegetation where soils are disturbed including but not limited to removal by clearing or grubbing; clearing or road- cutting associated with geotechnical exploration and assessment, percolation testing, or any other activity that is a condition of a permit application; or any activity which bares soil or rock or involves streambed alterations or the diversion or piping of any watercourse.
(s) "Maximum extent practicable" (MEP) shall have the same meaning as defined in the NPDES Order.
(t) "Natural drainage" means a naturally occurring drainage consisting of native soils such as a natural swale or topographic depression which gathers or conveys run-off to a permanent or intermittent watercourse or water body.
(u) "Natural System Management Practices" (NSMP) means stormwater practices implemented to restore and/or preserve predevelopment watershed functions in lieu of providing direct pollutant removal and hydromodification flow control. NSMPs may include structural or engineered elements, but these elements do not expressly provide pollutant removal. NSMPs include land restoration, land preservation and stream rehabilitation projects.
(v) "Non-Stormwater" means all discharges to and from the stormwater conveyance system that do not originate from precipitation.
(w) "NPDES Order" shall mean and refer to California Regional Water Quality Control Board, San Diego Region Order No. R9-2013-0001, NPDES No. CAS00109266, as the same may be amended, modified or replaced from time to time.
(x) "Offsite Alternative Compliance Project" means a project implemented, either as a structural BMP or a Natural System Management Practice, which provides a greater overall water quality Benefit to the watershed management area and offset stormwater pollutant control impacts and hydromodification flow control impacts associated with Priority Development Projects (PDPs). Offsite Alternative Compliance Projects (ACP) may be implemented as an applicant-implemented ACP in which the ACP is owned or constructed by the same party that is generating the PDP impact. ACPs may be either structural BMPs or stormwater management practices implemented to restore and/or preserve predevelopment watershed function of a natural system.
(y) "Pollutant" means any agent that may cause, potentially cause or contribute to the degradation of water quality such that a condition of pollution or contamination is created or aggravated.
(z) "Pollutant Control BMP" (PC-BMP) means any engineered system designed to remove pollutants from stormwater by simple gravity settling of particulate pollutants, filtration, biological uptake, media absorption or any other physical, biological, or chemical process. They are also known as treatment control BMPs.
(aa) "Pollution prevention" means the practices and processes that reduce or eliminate the generation of pollutants such as the use of smaller quantities of toxic materials or substitution of less toxic materials; changes to production processes to reduce waste; decreases in waste water flows; recycling of wastes as part of the production process; segregation of wastes, and treatment of wastes on site to decrease volume or toxicity.
(bb) "Priority Development Projects" (PDPs) are new development and redevelopment projects that are subject to general, source control site design, pollutant control, and hydromodification management BMP requirements, and that must demonstrate compliance through a stormwater quality management plan to be approved by the County.
(cc) "Public improvement projects" means any project for the erection, construction, alteration, repair or improvement of any public structure, building, road, or other public improvement of any kind.
(dd) "Rainy season" means from October 1 through April 30.
(ee) "Receiving waters" shall mean waters of the United States.
(ff) "Redevelopment" means creation, addition, or replacement of impervious surface on an already developed site. Examples include the expansion of building footprints, road widening, the addition or replacement of a structure, and creation or addition of impervious surfaces. Replacement of existing impervious surfaces includes any activity that is not part of a routine maintenance activity where impervious material(s) are removed exposing underlying soil during construction. Redevelopment does not include trenching and resurfacing associated with utility work, resurfacing existing roadways, new sidewalk construction, pedestrian ramps, or bike lane on existing roads; and routine replacement of damaged pavement, such as pothole repair.
(gg) "Residential discharger" means the occupant, owner, manager, caretaker, or owner's association that owns, occupies or has responsibility for a discharge from a single-family dwelling, a multiple-family dwelling, mobile home park, condominium complex, board-and-care house, or other housing structure or portion of a residential development from which the discharge originated.
(hh) "Regional Water Quality Control Board" or "RWQCB" means the California Regional Water Quality Control Board for the San Diego Region.
(ii) "Source control BMP" means land use or site planning practices, or structural or nonstructural measures that aim to prevent runoff pollution by reducing the potential for contamination at the source of pollution. Source control BMPs minimize the contact between pollutants and runoff.
(jj) "Stormwater conveyance system" means private and public drainage facilities other than sanitary sewers within the unincorporated area of San Diego County by which water run-off may be conveyed to receiving waters, and includes but is not limited to roads, streets, constructed channels, aqueducts, storm drains, pipes, street gutters, inlets to storm drains or pipes, or catch basins.
(kk) "Stormwater Quality Management Plan" or "SWQMP" means a plan, submitted on a County form or in a County approved format with an application for a County permit or other County approval, identifying the measures that will be used for stormwater and non-stormwater management for a development project. There are two types of SWQMPs: a Standard SWQMP and a PDP SWQMP. A PDP SWQMP is required for all Priority Development Projects. Standard SWQMPs are required for all other development projects.
(ll) "Stormwater pollution prevention plan" (SWPPP) means an approved site-specific plan that (1) identifies and evaluates sources of pollutants associated with activities that may affect the quality of stormwater discharges, (2) eliminates non-stormwater discharges, and (3) identifies and implements site-specific BMPs to reduce or to prevent pollutants in stormwater or retain non-stormwater discharges.
(mm) "Structural BMPs" are a subset of BMPs which detain, retain, filter, remove, or prevent the release of pollutants and control runoff discharge rates to surface waters from development projects in perpetuity, after construction of a project is completed. These BMPs can satisfy the requirements for Pollutant Control BMPs and Hydromodification BMP requirements for Priority Development Projects.
(nn) "SUSMP" or standard urban stormwater mitigation plan for land development projects and public improvement projects means the SUSMP adopted by the County Board of Supervisors on November 13, 2002 pursuant to California Regional Water Quality Control Board Order No. 2001-01, as it may thereafter be revised by the Director, Department of Public Works. The County BMP Design Manual will supersede the SUSMP pursuant to the NPDES Order.
(oo) "Treatment control BMPs" are also known as a Pollutant Control BMPs (PC-BMPs).
(pp) "Tributary to an impaired water body" means any facility or activity that is a tributary to an impaired water body because urban run-off from that facility or activity enters (1) the stormwater conveyance system at a place and in a manner that will carry pollutants for which that water body is impaired to the impaired water body; (2) a flowing stream that will carry pollutants for which that water body is impaired to the impaired water body; or (3) an ephemeral stream that reaches the impaired water body during storm events and that will carry pollutants for which that water body is impaired during such storm events.
(qq) "Water quality standards" mean those regionally determined beneficial uses and water quality objectives in applicable water quality control and basin plans, together with anti-degradation policies that serve as water quality standards under the Clean Water Act.
(rr) "Watershed Management Areas" mean those areas identified in Table B-1 of the NPDES Order where the County is identified as a responsible Copermittee.
(ss) "Watershed Management Area Analysis" means the analysis completed pursuant to Section II.B.3.b.(4) of the NPDES Order.
(tt) "Water Quality Improvement Plans" mean the plans developed by the County in accordance with Section II.B. of the NPDES Order for the Watershed Management Areas.
(Added by Ord. No. 9424 (N.S.), effective 2-20-02; amended by Ord. No. 9518 (N.S.), effective 1-10-03; amended by Ord. No. 9589 (N.S.), effective 9-5-03; amended by Ord. No. 9926 (N.S.), effective 4-11-08; amended by Ord. No. 9999 (N.S.), effective 9-4-09; amended by Ord. No. 10030 (N.S.), effective 1-13-10; amended by Ord. No. 10096 (N.S.), effective 1-7-11; amended by Ord. No. 10224 (N.S.), effective 10-25-12; amended by Ord. No. 10385 (N.S.), effective 6-12-15; amended by Ord. No. 10410 (N.S.), effective 2-26-16; amended by Ord. No. 10709 (N.S.), effective 1-15-21)