For the purposes of this chapter, the following words and phrases shall have the meanings respectively ascribed to them by this chapter, unless clearly inapplicable. Words and phrases not ascribed a meaning by this chapter shall have the meanings ascribed by the "Waste Discharge Requirements for Municipal Separate Storm Sewer System (MS4) Discharges within the Coastal Watersheds of Los Angeles County, Except those Discharges Originating from the City of Long Beach MS4," issued by the California Regional Water Quality Control Board—Los Angeles Region (Order No. R4-2012-0175), or as modified by the State Water Resources Control Board, if defined therein, and if not, by the regulations implementing Clean Water Act Section 402, and Division
7 of the California Water Code, as they may be amended from time to time, if defined therein, and if not, to the definitions in an applicable permit issued by the California Regional Water Quality Control Board—Los Angeles (Regional Board), as such permits may be amended from time to time.
means a facility that is categorized in any one (1) of the following Standard Industrial Classification (SIC) and North American Industry Classification System (NAICS) codes. For inspection purposes, permittees need not inspect facilities with SIC codes 5013, 5014, 5541, and 5511, provided these facilities have no outside activities or materials that may be exposed to stormwater. (Source: Order No. R4-2012-0175.)
"Basin plan"means the Water Quality Control Plan, Los Angeles Region, Basin Plan for the Coastal Watersheds of Los Angeles and Ventura Counties, adopted by the Regional Water Board on June 13, 1994, and subsequent amendments. (Source: Order No. R4-2012-0175.)
"Best management practice (BMP)"means any practices or physical devices or systems designed to prevent or reduce pollutant loading from stormwater or nonstormwater discharges to receiving waters, or designed to reduce the volume of stormwater or nonstormwater discharged to the receiving water. (Source: Order No. R4-2012-0175.)
"Biofiltration"means a LID BMP that reduces stormwater pollutant discharges by intercepting rainfall on vegetative canopy, and through incidental infiltration and/or evapotranspiration, and filtration. Incidental infiltration is an important factor in achieving the required pollutant load reduction. Therefore, the term "biofiltration," as used in this chapter, is defined to include only systems designed to facilitate incidental infiltration or achieve the equivalent pollutant reduction as biofiltration BMPs with an underdrain (subject to approval by the Regional Board's Executive Officer). Biofiltration BMPs include bioretention systems with an underdrain and bioswales. (Modified from: Order No. R4-2012-0175.)
"Bioretention"means a LID BMP that reduces stormwater runoff by intercepting rainfall on vegetative canopy, and through evapotranspiration and infiltration. The bioretention system typically includes a minimum two (2) foot top layer of a specified soil and compost mixture underlain by a gravel-filled temporary storage pit dug into the in-situ soil. As defined in the municipal NPDES permit, a bioretention BMP may be designed with an overflow drain, but may not include an underdrain. When a bioretention BMP is designed or constructed with an underdrain it is regulated by the municipal NPDES permit as biofiltration. (Modified from: Order No. R4-2012-0175.)
"Bioswale"means a LID BMP consisting of a shallow channel lined with grass or other dense, low-growing vegetation. Bioswales are designed to collect stormwater runoff and to achieve a uniform sheet flow through the dense vegetation for a period of several minutes. (Source: Order No. R4-2012-0175.)
"Clean Water Act (CWA)"means the Federal Water Pollution Control Act enacted in 1972, by Public Law 92-500, and amended by the Water Quality Act of 1987. The Clean Water Act prohibits the discharge of pollutants to waters of the United States unless the discharge is in accordance with an NPDES permit.
"Commercial malls"means any development comprised of one (1) or more buildings forming a complex of stores, which sells various merchandise, with interconnecting walkways enabling visitors to easily walk from store to store, along with parking area(s). A commercial mall includes, but is not limited to: mini-malls, strip malls, other retail complexes, and enclosed shopping malls or shopping centers. (Source: Order No. R4-2012-0175.)
"Construction activity"means any construction or demolition activity, clearing, grading, grubbing, or excavation or any other activity that results in land disturbance. Construction does not include emergency construction activities required to immediately protect public health and safety or routine maintenance activities required to maintain the integrity of structures by performing minor repair and restoration work, maintain the original line and grade, hydraulic capacity, or original purposes of the facility. See "routine maintenance" definition for further explanation. Where clearing, grading, or excavating of underlying soil takes place during a repaving operation, State general construction permit coverage by the State of California general permit for stormwater discharges associated with industrial activities or for stormwater discharges associated with construction activities is required if more than one (1) acre is disturbed or the activities are part of a larger plan. (Source: Order No. R4-2012-0175.)
"Control"means to minimize, reduce, or eliminate by technological, legal, contractual, or other means, the discharge of pollutants from an activity or activities. (Source: Order No. R4-2012-0175.)
"Development"means construction, rehabilitation, redevelopment, or reconstruction of any public or private residential project (whether single-family, multi-unit, or planned unit development); industrial, commercial, retail, and other nonresidential projects, including public agency projects or mass grading for future construction. It does not include routine maintenance to maintain original line and grade, hydraulic capacity, or original purpose of facility, nor does it include emergency construction activities required to immediately protect public health and safety. (Source: Order No. R4-2012-0175.)
"Directly adjacent"means situated within two hundred (200) feet of the contiguous zone required for the continued maintenance, function, and structural stability of the environmentally sensitive area. (Source: Order No. R4-2012-0175.)
"Discharge"means any release, spill, leak, pump, flow, escape, dumping, or disposal of any liquid, semi-solid, or solid substance.
"Disturbed area"means an area that is altered as a result of clearing, grading, and/or excavation. (Source: Order No. R4-2012-0175.)
"Flow-through BMPs"means modular, vault type "high flow biotreatment" devices contained within an impervious vault with an underdrain or designed with an impervious liner and an underdrain. (Modified from: Order No. R4-2012-0175.)
"Green roof"means a LID BMP using planter boxes and vegetation to intercept rainfall on the roof surface. Rainfall is intercepted by vegetation leaves and through evapotranspiration. Green roofs may be designed as either a bioretention BMP or as a biofiltration BMP. To receive credit as a bioretention BMP, the green roof system planting medium shall be of sufficient depth to provide capacity within the pore space volume to contain the design storm depth and may not be designed or constructed with an underdrain. (Source: Order No. R4-2012-0175.)
"Hillside"means a property located in an area with known erosive soil conditions, where the development contemplates grading on any natural slope that is twenty-five percent (25%) or greater and where grading contemplates cut or fill slopes. (Source: Order No. R4-2012-0175.)
"Hydromodification"means the alteration of the hydrologic characteristics of coastal and noncoastal waters, which in turn could cause degradation of water resources. Hydromodification can cause excessive erosion and/or sedimentation rates, causing excessive turbidity, channel aggradation, and/or degradation. (Source: general construction activities stormwater permit.)
"Impervious surface"means any manmade or modified surface that prevents or significantly reduces the entry of water into the underlying soil, resulting in runoff from the surface in greater quantities and/or at an increased rate, when compared to natural conditions prior to development. Examples of places that commonly exhibit impervious surfaces include parking lots, driveways, roadways, storage areas, and rooftops. The imperviousness of these areas commonly results from paving, compacted gravel, compacted earth, and oiled earth.
"Industrial park"means land development that is set aside for industrial development. Industrial parks are usually located close to transport facilities, especially where more than one (1) transport modalities coincide: highways, railroads, airports, and navigable rivers. It includes office parks, which have offices and light industry. (Source: Order No. R4-2012-0175.)
"Infiltration BMP"means a LID BMP that reduces stormwater runoff by capturing and infiltrating the runoff into in-situ soils or amended on-site soils. Examples of infiltration BMPs include infiltration basins, dry wells, and pervious pavement. (Source: Order No. R4-2012-0175.)
"Low impact development (LID)"means any building and landscape features designed to retain or filter stormwater runoff. (Source: Order No. R4-2012-0175.)
"MS4"means municipal separate storm sewer system (MS4). The MS4 is a conveyance or system of conveyances (including roads with drainage systems, municipal streets, catch basins, curbs, gutters, ditches, manmade channels, or storm drains):
1. Owned or operated by a state, city, town, borough, county, parish, district, association, or other public body (created by or pursuant to State law) having jurisdiction over disposal of sewage, industrial wastes, stormwater, or other wastes, 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 CWA that discharges to waters of the United States;
Designed or used for collecting or conveying stormwater;
Which is not a combined sewer; and
Which is not part of a publicly owned treatment works, as defined in
40 C.F.R. Section 122.2.26(b)(8). (Source: Order No. R4-2012-0175.)
"National Pollutant Discharge Elimination System (NPDES)"means the national program for issuing, modifying, revoking and reissuing, terminating, monitoring and enforcing permits, and imposing and enforcing pretreatment requirements, under CWA Sections 307, 402, 318, and 405. The term includes an "approved program." (Source: Order No. R4-2012-0175.)
"Natural drainage system"means a drainage system that has not been improved (e.g., channelized or armored). The clearing or dredging of a natural drainage system does not cause the system to be classified as an improved drainage system. (Source: Order No. R4-2012-0175.)
"New development"means land-disturbing activities; structural development, including construction or installation of a building or structure, creation of impervious surfaces; and land subdivision. (Source: Order No. R4-2012-0175.)
"Nonstormwater discharge"means any discharge to a municipal storm drain system not composed entirely of stormwater. (Source: Order No. R4-2012-0175.)
"Parking lot"means an area or facility for the temporary parking or storage of motor vehicles used for businesses or commerce, industry, or personal use, with a lot size of five thousand (5,000) square feet or more of surface area, or with twenty-five (25) or more parking spaces. (Source: Order No. R4-2012-0175.)
"Planning priority projects"means development projects subject to permittee conditioning and approval for the design and implementation of post-construction controls to mitigate stormwater pollution, prior to completion of the project(s). (Modified from: Order No. R4-2012-0175.)
"Pollutant"means any pollutant defined in Section 502(6) of the Federal Clean Water Act or incorporated into the California Water Code Section
13373. Pollutants may include, but are not limited to, the following:
1. Commercial and industrial wastes (such as fuels, solvents, detergents, plastic pellets, hazardous substances, fertilizers, pesticides, slag, ash, and sludge).
Metals (such as cadmium, lead, zinc, copper, silver, nickel, chromium, and nonmetals such as phosphorus and arsenic).
Petroleum hydrocarbons (such as fuels, lubricants, surfactants, waste oils, solvents, coolants, and grease).
Excessive eroded soil, sediment, and particulate materials in amounts that may adversely affect the beneficial use of the receiving waters, flora, or fauna of the State.
Animal wastes (such as discharge from confinement facilities, kennels, pens, recreational facilities, stables, and show facilities).
Substances having characteristics such as pH less than six or greater than nine, or unusual coloration or turbidity, or excessive levels of fecal coliform, or fecal streptococcus, or enterococcus.
"Project"means all development, redevelopment, and land-disturbing activities. The term is not limited to "project" as defined under CEQA (Public Resources Code Section
21065). (Source: Order No. R4-2012-0175.)
means a LID BMP system designed to capture runoff, typically from a roof, but can also include runoff capture from elsewhere within the site, and to provide for temporary storage until the harvested water can be used for irrigation or nonpotable uses. The harvested water may also be used for potable water uses if the system includes disinfection treatment and is approved for such use by the local building department. (Source: Order No. R4-2012-0175.)
"Receiving water"means water of the United States into which waste and/or pollutants are or may be discharged. (Source: Order No. R4-2012-0175.)
"Redevelopment"means land-disturbing activity that results in the creation, addition, or replacement of five thousand (5,000) square feet or more of impervious surface area on an already developed site. Redevelopment includes, but is not limited to: the expansion of a building footprint; addition or replacement of a structure; replacement of impervious surface area that is not part of routine maintenance activity; and land-disturbing activity related to structural or impervious surfaces. It does not include routine maintenance to maintain original line and grade, hydraulic capacity, or original purpose of facility, nor does it include emergency construction activities required to immediately protect public health and safety. (Source: Order No. R4-2012-0175.)
"Restaurant"means a facility that sells prepared foods and drinks for consumption, including stationary lunch counters and refreshment stands selling prepared foods and drinks for immediate consumption (SIC Code 5812). (Source: Order No. R4-2012-0175.)
"Retail gasoline outlet"means any facility engaged in selling gasoline and lubricating oils. (Source: Order No. R4-2012-0175.)
"Routine maintenance"means, but is not limited to, projects conducted to:
1. Maintain the original line and grade, hydraulic capacity, or original purpose of the facility.
Perform as-needed restoration work to preserve the original design grade, integrity and hydraulic capacity of flood control facilities.
Includes road shoulder work, regrading dirt or gravel roadways and shoulders, and performing ditch clean-outs.
Replacing existing lines with new materials or pipes and updating facilities to comply with applicable codes, standards, and regulations regardless if such projects result in increased capacity.
Repair leaks.
Routine maintenance does not include construction of new lines (i.e., that are not associated with existing facilities and are not part of a project to update or replace existing lines) or facilities resulting from compliance with applicable codes, standards, and regulations. (Source: Order No. R4-2012-0175.) |
"Significant ecological areas (SEAs)"means areas that are determined to possess an example of biotic resources that cumulatively represent biological diversity, for the purposes of protecting biotic diversity, as part of the City of Santa Clarita General Plan. Areas are designated as SEAs if they possess one (1) or more of the following criteria:
1. The habitat of rare, endangered, and threatened plant and animal species.
Biotic communities, vegetative associations, and habitat of plant and animal species that are either one of a kind or are restricted in distribution on a regional basis.
Biotic communities, vegetative associations, and habitat of plant and animal species that are either one of a kind or are restricted in distribution in Los Angeles County.
Habitat that, at some point in the life cycle of a species or group of species, serves as a concentrated breeding, feeding, resting, or migrating grounds and is limited in availability either regionally or within Los Angeles County.
Biotic resources that are of scientific interest because they are either an extreme in physical/geographical limitations, or represent an unusual variation in a population or community.
Areas important as game species habitat or as fisheries.
Areas that would provide for the preservation of relatively undisturbed examples of natural biotic communities in Los Angeles County.
Special areas. (Source: Order No. R4-2012-0175.)
"Site"means land or water area where any facility or activity is physically located or conducted, including adjacent land used in connection with the facility or activity. (Source: Order No. R4-2012-0175.)
"Storm drain system"means any facilities or any part of those facilities, including streets, gutters, conduits, natural or artificial drains, channels, and watercourses, that are used for the purpose of collecting, storing, transporting or disposing of stormwater.
"Storm water" or "stormwater"means water that originates from atmospheric moisture (rain or snow) and that falls onto land, water, or other surfaces. Without any change in its meaning, this term may be spelled or written as one (1) word or two (2) separate words.
"Stormwater runoff"means that part of precipitation (rainfall or snowmelt), which travels across a surface to the storm drain system or receiving waters.
"SUSMP"means the Los Angeles Countywide Standard Urban Stormwater Mitigation Plan. The SUSMP was required as part of the previous municipal NPDES permit (Order No. 01-182, NPDES No. CAS004001) and required plans that designate best management practices (BMPs) that must be used in specified categories of development projects.
"Urban runoff"means surface water flow produced by storm and nonstorm events that is shed from both pervious and nonpervious surfaces. Nonstorm events that produce urban runoff include flow from residential, commercial, or industrial activities involving the use of potable and nonpotable water.
(Ord. 13-8 § 4 (Exh. A), 6/11/2013; Ord. 15-4 § 1, 5/26/2015)