“Best management practice (BMP)” shall mean the schedules of activities, prohibitions of practices, maintenance procedures, and structural and/or managerial practices that, when used singly or in combination, prevent or reduce the release of pollutants and other adverse impacts to waters of Washington State.

“Critical area” shall refer to geologically hazardous areas, wetlands, lakes, ponds, streams, frequently flooded (flood hazard) areas, and fish and wildlife habitat conservation areas, as defined in Chapter 36.70A RCW and Chapter 19.37 EMC.

“Design and Construction Standards and Specifications” or “DCSS” shall mean the current City of Everett Design and Construction Standards and Specifications.

“Developer” shall mean the owning individual(s) or entity(ies) or their representative applying for the permits or approvals described in EMC 14.28.030.

“Development” is defined in EMC 19.04.020.

“Director” shall mean the director of public works and/or designees.

“Hard surface” means an impervious surface, permeable pavement, or a vegetated roof.

“Illicit connection” means any infrastructure connection to the stormwater drainage system that is not intended, permitted, or used for collecting and conveying stormwater or nonstormwater discharges. Examples include sanitary sewer connections, floor drains, channels, pipelines, conduits, inlets, or outlets that are connected directly to the MS4.

“Illicit discharge” means any discharge that is not composed entirely of stormwater to any portion of the stormwater drainage system, ground water, or surface water.

“Impervious surface” means a nonvegetated surface area that either prevents or retards the entry of water into the soil mantle as under natural conditions prior to development. A nonvegetated 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, roof tops, walkways, patios, driveways, parking lots or storage areas, concrete or asphalt paving, gravel roads, packed earthen materials, and oiled macadam, or other surfaces which similarly prevent the natural infiltration of stormwater.

“Land disturbing activity” means any activity that results in a change in the existing soil cover (both vegetative and nonvegetative) and/or the existing soil topography. Land disturbing activities include, but are not limited to, clearing, grading, filling, and excavation. Compaction that is associated with stabilization of structures and road construction shall also be considered land disturbing activity. Vegetation maintenance practices, including landscape maintenance and gardening, are not considered land disturbing activity. Stormwater facility maintenance is not considered land disturbing activity if conducted according to established standards and procedures.

“Low impact development best management practices” shall mean distributed stormwater management practices, integrated into a project design, that emphasize pre-disturbance hydrologic processes of infiltration, filtration, storage, evaporation and transpiration.

“Maintenance” includes repair and maintenance activities conducted on currently serviceable structures, facilities, and equipment that involve no expansion or use beyond that previously existing and result in no significant adverse hydrologic impact. It includes those usual activities taken to prevent decline, lapse, or cessation in the use of structures and systems. Those usual activities may include replacement of dysfunctional facilities, including cases where environmental permits require replacing an existing structure with a different type structure, as long as the functioning characteristics of the original structure are not changed. One example is the replacement of a collapsed, fish blocking, round culvert with a new box culvert under the same span, or width of roadway. In regard to stormwater facilities, maintenance includes assessment to ensure ongoing proper operation, removal of built-up pollutants (i.e., sediments), replacement of failed or failing treatment media, and other actions taken to correct defects as identified in the maintenance standards of the city’s stormwater management manual.

“Minimum requirements” for stormwater management at new development and redevelopment sites is as defined in the stormwater management manual.

“Natural location” of drainage system shall refer to the location of those channels, swales, and other conveyance systems as defined by the topographic contours existing for the subject property, from city of Everett aerial topographic maps dated April 8, 1969, and April 25, 1971. In cases where the above maps are inconclusive, “natural location” shall refer to the existing features unless it can be shown from documented maps or photographs that the features have existed less than ten years. In cases of disagreement, the decision of the city engineer as to “natural location” shall be final.

“New development” means the following activities: land disturbing activities, including Class IV general forest practices that are conversions from timber land to other uses; structural development, including construction, installation or expansion of a building or other structure; creation of hard surfaces; and subdivision, short subdivision, and binding site plans as defined and applied in Chapter 58.17 RCW. Projects meeting the definition of redevelopment shall not be considered new development.

“Receiving water body or receiving waters” means naturally and/or reconstructed naturally occurring surface water bodies, such as creeks, streams, rivers, lakes, wetlands, estuaries, and marine waters, or ground water, to which a stormwater system discharges.

“Redevelopment” means a site that is already substantially developed (i.e., has thirty-five percent or more of existing impervious surface coverage), the creation or addition of hard surfaces; the expansion of a building footprint or addition or replacement of a structure; structural development including construction, installation or expansion of a building or other structure; replacement of hard surface that is not part of a routine maintenance activity; and land disturbing activities.

“Regional stormwater facility” shall mean and include (1) a single stormwater BMP/facility designed to provide stormwater treatment and/or flow control for a large region or portion of a basin or subbasin, or (2) multiple stormwater BMPs/facilities that are designed to provide water quality and/or flow control for a large region or portion of a basin or subbasin.

“Replaced hard surface” means, for structures, the removal and replacement of hard surfaces down to the foundation. For other hard surfaces, the removal down to bare soil or base course and replacement.

“Replaced impervious surface” means, for structures, the removal and replacement of impervious surfaces down to the foundation. For other impervious surfaces, the removal down to bare soil or base course and replacement.

“Site” means the area defined by the legal boundaries of a parcel or parcels of land that is (are) subject to new development or redevelopment. For road projects, the length of the project site and the right-of-way boundaries define the site.

“Source control BMP” means the structure or operation that is 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. The stormwater management manual separates source control BMPs into two types. Structural source control BMPs are physical, structural, or mechanical devices, or facilities that are intended to prevent pollutants from entering stormwater. Operational BMPs are nonstructural practices that prevent or reduce pollutants from entering stormwater.

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

“Stormwater drainage system” shall mean constructed and natural features which function together as a system to collect, convey, channel, hold, inhibit, retain, detain, infiltrate, divert, treat or filter stormwater.

“Stormwater facility” shall mean a constructed component of a stormwater drainage system, designed or constructed to perform a particular function, or multiple functions. Stormwater facilities include, but are not limited to, pipes, swales, ditches, culverts, street gutters, detention ponds, retention ponds, constructed wetlands, infiltration devices, catch basins, oil/water separators, pumps, outfall, biofiltration swales, and stormwater treatment and flow control and LID BMPS.

“Stormwater management manual” shall mean the Washington State Department of Ecology Stormwater Management Manual for Western Washington adopted by the director, along with any technical and administrative procedures established by the director, which provide details for implementation of the provisions of this chapter.

“Stormwater site plan” shall mean the comprehensive report containing all of the technical information and analysis necessary for the city to evaluate a proposed new development or redevelopment for compliance with stormwater requirements.

“Surface waters” includes lakes, rivers, ponds, streams, wetlands, inland waters, salt waters and all other surface waters and water courses within the jurisdiction of the state of Washington.

“Water quality standards” shall mean surface water quality standards, Chapter 173-201A WAC, ground water quality standards, Chapter 173-200 WAC, and sediment management standards, Chapter 173-204 WAC.

“Waters of the state” shall mean those waters as defined as “waters of the United States” in 40 CFR Subpart 122.2 within the geographic boundaries of Washington State and “waters of the State” as defined in Chapter 90.48 RCW which includes lakes, rivers, ponds, streams, inland waters, underground waters, salt waters, and all other surface waters and water courses within the jurisdiction of the state of Washington. (Ord. 3880-22 § 4 (Exh. A), 2022.)