Chapter 11.03
STORMWATER AND SURFACE WATER DEFINITIONS

Sections:

11.03.010    Definitions

11.03.010 Definitions.

(a)    “AKART” means all known, available, and reasonable methods of prevention, control, and treatment. See also the State Water Pollution Control Act, RCW 90.48.010 and 90.48.520.

(b)    “Aquatic habitat” or “aquatic resource” means the portion of the water body below the surface, including fluctuating elevations, aquatic or emergent plants, substrate, water quality, and other physical characteristics of a waterbody regarding its ability to support wildlife.

(c)    “Best management practices (BMPs)” means schedules of activities, prohibitions of practices, general good housekeeping practices, pollution prevention and educational practices, maintenance procedures, and structural or managerial practices to prevent or reduce the discharge of pollutants directly or indirectly to stormwater, receiving waters, or stormwater conveyance systems. BMPs also include treatment practices, operating procedures, and practices to control site runoff, spillage or leaks, sludge or water disposal, or drainage from raw materials storage.

(d)    “Developed parcel” means any parcel altered from the natural state by construction, creation, or addition of impervious surfaces.

(e)    “Equivalent service unit” means the average impervious surface area of single-family residential properties in the City.

(f)    “Ground water” or “groundwater” means water in a saturated zone or stratum beneath the surface of the land or below a surface water body.

(g)    “Hazardous materials” means any material, including any substance, waste, or combination thereof, which because of its quantity, concentration, or physical, chemical, or infectious characteristics may cause, or significantly contribute to, a substantial present or potential hazard to human health, safety, property or the environment when improperly treated, stored, transported, disposed of, or otherwise managed.

(h)    “Hyperchlorinated” means water that contains more than 10 mg/liter chlorine.

(i)    “Illicit connection” means any manmade conveyance that is connected to a municipal separate storm sewer without a permit, excluding roof drains and other similar type connections. Examples include sanitary sewer connections, floor drains, channels, pipelines, conduits, inlets, or outlets that are connected directly to the municipal separate storm sewer system.

(j)    “Illicit discharge” means any direct or indirect nonstormwater discharge to the City’s storm drain system, except as expressly exempted by this chapter.

(k)    “Impervious surface” means a hard surface area which either prevents or retards the entry of water into the soil mantle as it entered under natural conditions prior to development, and/or a hard surface area which causes water to run off the surface in greater quantities or at an increased rate of flow from the flow present under natural conditions prior to development. Common impervious surfaces include, but are not limited to, roofs, walkways, patios, driveways, parking lots, storage areas, areas which are paved, graveled or made of packed or oiled earthen materials, or other surfaces which similarly impede the natural infiltration of surface and stormwater. Open, uncovered retention/detention facilities shall not be considered as impervious surfaces for the purpose of this chapter.

(l)    “Low impact development (LID)” is a common stormwater management approach prescribed through the Stormwater Manual. The intent of LID as a stormwater approach is to mimic a site’s predevelopment hydrology by employing design techniques that infiltrate, store, evaporate and detain runoff close to its source.

(m)    “Maintenance” means the act or process of cleaning, repairing or preserving a system, unit, facility, structure or piece of equipment.

(n)    “Municipal separate storm sewer system (MS4)” means a conveyance or system of conveyances, including roads with drainage systems, municipal streets, catch basins, curbs, gutters, ditches, manmade channels, or storm drains, which are:

(1)    Owned or operated by the City of Lake Stevens;

(2)    Designed or used for collecting or conveying stormwater;

(3)    Not part of a publicly owned treatment works (POTW) (“POTW” means any device or system used in treatment of municipal sewage or industrial wastes of a liquid nature which is publicly owned); and

(4)    Not a combined sewer (“combined sewer” means a system that collects sanitary sewage and stormwater in a single sewer system).

(o)    “National Pollutant Discharge Elimination System (NPDES) Stormwater Discharge Permit” means a permit issued by the Environmental Protection Agency (EPA) (or by the Washington Department of Ecology under authority delegated pursuant to 33 USC Section 1342(b)) that authorizes the discharge of pollutants to waters of the United States, whether the permit is applicable on an individual, group, or general area-wide basis.

(p)    “Nonstormwater discharge” means any discharge to the storm drain system that is not composed entirely of stormwater.

(q)    “Open space” means any parcel, property, or portion thereof classified for current use taxation under the provisions of Chapter 84.34 RCW, or for which the development rights have been sold to the City of Lake Stevens.

(r)    “Operational source control BMP” means a schedule of activities, prohibition of practices, and other best management practices to prevent or reduce pollutants from entering stormwater.

(s)    “Parcel” means the smallest separately segregated unit or plot of land having an identified owner, boundaries and surface area which is documented for property tax purposes and given a tax number by the Snohomish County Assessor.

(t)    “Person” means any individual, association, organization, partnership, firm, corporation or other entity recognized by law and acting as either the owner of a premises or as the owner’s agent.

(u)    “Pollution” means any pollutants which cause or contribute to adverse ecological effects or degradation. Pollutants may include, but are not limited to: paints, varnishes, and solvents; oil and other automotive fluids; nonhazardous liquid and solid wastes and yard wastes; refuse, rubbish, garbage, litter, or other discarded or abandoned objects and accumulations, so that same may cause or contribute to pollution; floatables; pesticides, herbicides, and fertilizers; hazardous substances and wastes; sewage, fecal coliform and pathogens; dissolved and particulate metals; animal wastes; wastes and residues that result from constructing a building or structure; and noxious or offensive matter of any kind.

(v)    “Potential pollutant site” means a business or activity on private property to be inspected under the source control program that includes, but is not limited to, existing business, industrial, manufacturing, processing, or other commercial facility located within the City which generates significant quantities of materials listed in this title as pollution or prohibited contaminants. A potential pollution site is evaluated by the extent to which said materials may be located in outdoor conditions, may interact with stormwater or surface water, and may result in contaminants as a prohibited discharge to receiving waters or the City’s MS4.

(w)    “Receiving waters” means bodies of water or surface water systems to which surface runoff is discharged via a point source of stormwater or via sheet flow. Groundwater to which surface runoff is directed by infiltration.

(x)    “Retention/detention facility” means a type of drainage facility designed either to hold water for a considerable length of time and then release it by evaporation, plant transpiration and/or infiltration into the ground or to hold runoff for a short period of time and then release it to the surface and stormwater management system.

(y)    “Residence” means a building or structure, or portion thereof, designed for and used to provide a place of abode for human beings. The term “residence” includes the term “residential” or “residential unit” as referring to the type of or intended use of a building or structure.

(z)    “Residential parcel” means any parcel which contains no more than two residences or two residential units which are within a single structure and are used primarily for residential purposes or any parcel which does not have impervious surfaces upon it.

(aa)    “Storm or stormwater drainage system” means publicly owned facilities, including the City’s municipal separate storm sewer system, by which stormwater is collected and/or conveyed, including but not limited to any roads with drainage systems, municipal streets, gutters, curbs, inlets, piped storm drains, pumping facilities, retention and detention basins, natural and human-made or altered drainage channels, reservoirs, and other drainage structures.

(bb)    “Stormwater” means runoff during and following precipitation and snowmelt events, including surface runoff and drainage.

(cc)    “Stormwater Manual” means the adopted Washington State Department of Ecology Stormwater Management Manual for Western Washington.

(dd)    “Stormwater pollution prevention plan (SWPPP)” means a document which describes the best management practices and activities to be implemented by a person to identify sources of pollution or contamination at a premises and the actions to eliminate or reduce pollutant discharges to stormwater, stormwater conveyance systems, and/or receiving waters to the maximum extent practicable.

(ee)    “Source control” or “source control BMP” means a best management practice listed in the Stormwater Manual intended to prevent pollutants from coming into contact with stormwater through physical separation of areas or careful management of activities that are sources of pollutants and thus avoiding a polluted discharge to surface water.

(ff)    “Structural source control BMP” means a physical, structural, or mechanical device or facility that is intended to prevent pollutants from entering stormwater as a best management practice.

(gg)    “Surface water” means the physical beds and boundaries of receiving waters (perennial, seasonal, and ephemeral streams, rivers, sloughs, wetlands, and lakes), including those natural drainage systems that have been altered by human actions.

(hh)    “Surface and stormwater utility services” means the services provided by the stormwater utility, including, but not limited to, stormwater management planning, facilities maintenance, regulation, financial administration, public involvement, drainage investigation and enforcement, aquatic resource restoration, surface and stormwater quality and environmental monitoring, natural surface water drainage system planning, intergovernmental relations, and facility design and construction.

(ii)    “Treatment BMP” means a best management practice that is intended to remove pollutants from stormwater.

(jj)    “Undeveloped parcel” means any parcel which has not been altered from its natural state by construction, creation or addition of impervious surfaces. (Ord. 1151, Sec. 1 (Exh. A), 2022; Ord. 1032, Sec. 1, 2018; Ord. 1010, Sec. 2 (Exh. A), 2018; Ord. 808, Sec. 1 (Exh. A), 2009; Ord. 549, 1997. Formerly 11.04.040, 11.06.100)