Chapter 13.10
DEFINITIONS

Sections:

13.10.010    Scope of chapter.

13.10.020    Adjustment.

13.10.030    AKART.

13.10.040    Applicant.

13.10.050    Basin.

13.10.060    Basin plan.

13.10.070    Best management practices.

13.10.080    City.

13.10.090    Closed depression.

13.10.100    Clean Water Act.

13.10.110    Construct or modify.

13.10.120    Conveyance system.

13.10.130    Department.

13.10.140    Development.

13.10.150    Developed parcel.

13.10.160    Director.

13.10.170    Division.

13.10.180    Discharge.

13.10.190    Drainage.

13.10.200    Drainage facility.

13.10.210    Drainage review.

13.10.220    Effective impervious surface.

13.10.225    Equivalent service unit (ESU).

13.10.230    Erosion and sediment control.

13.10.240    Farm management plan.

13.10.250    Financial guarantee.

13.10.260    Flood hazard reduction plan.

13.10.270    Flow control best management practice.

13.10.280    Flow control facility.

13.10.290    Forest practices.

13.10.300    Full drainage review.

13.10.310    Groundwater.

13.10.320    High-use site.

13.10.330    Hydraulically connected.

13.10.340    Impervious surface.

13.10.350    Improvement.

13.10.360    Land disturbing activity.

13.10.370    Land use code.

13.10.380    Lake management plan.

13.10.390    Large project drainage review.

13.10.400    Licensed civil engineer.

13.10.410    Maintenance.

13.10.415    Manager.

13.10.420    Master drainage plan.

13.10.421    Municipal separate storm sewer systems.

13.10.430    National Pollutant Discharge Elimination System.

13.10.440    National Pollutant Discharge Elimination System permit.

13.10.450    Native vegetated surface.

13.10.460    Natural discharge location.

13.10.470    Natural surface water drainage system.

13.10.480    New impervious surface.

13.10.490    New pervious surface.

13.10.500    Open space.

13.10.510    Parcel.

13.10.520    Person.

13.10.525    Pervious surface.

13.10.530    Pollution-generating impervious surface.

13.10.540    Pollution-generating pervious surface.

13.10.550    Project.

13.10.560    Project site.

13.10.570    Rate category.

13.10.580    Redevelopment project.

13.10.590    Replaced impervious surface.

13.10.600    Residence.

13.10.610    Residential parcel.

13.10.615    Road.

13.10.620    Runoff.

13.10.630    Salmon conservation plan.

13.10.640    Shared facility.

13.10.650    Service area.

13.10.651    Service charges.

13.10.655    Simplified drainage review.

13.10.656    Single-family residence.

13.10.660    Site.

13.10.670    Repealed.

13.10.680    Source control BMP.

13.10.690    State Waste Discharge Permit.

13.10.700    Stormwater compliance plan.

13.10.710    Stormwater plan.

13.10.720    Stormwater Pollution Prevention Manual.

13.10.730    Subbasin.

13.10.740    Surface and stormwater.

13.10.750    Surface water utility.

13.10.760    Surface and stormwater management system.

13.10.770    Surface Water Design Manual.

13.10.780    Surface water management fee protocols.

13.10.790    Treatment BMP.

13.10.800    Targeted drainage review.

13.10.810    Undeveloped parcel.

13.10.815    Unit rate.

13.10.820    Water quality facility.

13.10.010 Scope of chapter.

This chapter contains definitions of technical and procedural terms used throughout this title. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.020 Adjustment.

“Adjustment” means a department-approved variation in the application of the requirements of Chapter 13.20 SMC and the Surface Water Design Manual to a particular project in accordance with SMC 13.20.030. “Adjustment” replaces “variance,” which was used in prior editions of the Surface Water Design Manual. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.030 AKART.

“AKART” means “all known, available and reasonable methods of prevention, control and treatment.” “AKART” represents the most current methodology that can be reasonably required for preventing, controlling or abating the pollutants associated with a discharge. “AKART” applies to both point and nonpoint sources of pollution. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.040 Applicant.

“Applicant” means a property owner or a public agency or public or private utility that owns a right-of-way or other easement or has been adjudicated the right to such an easement under RCW 8.12.090, or any person or entity designated or named in writing by the property or easement owner to be the applicant, in an application for a development proposal, permit or approval. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.050 Basin.

“Basin” means a geographic area that contains and drains to a stream or river named and noted on common maps, such as the Cedar River, Sammamish River, Green River, Snoqualmie River, Skykomish River or White River, or a geographic area that drains to a nonflowing water body named and noted on common maps, such as Lake Washington or Puget Sound. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.060 Basin plan.

“Basin plan” means a plan and all implementing regulations and procedures including, but not limited to, capital projects, public education activities and land use management regulations adopted by ordinance for managing surface and stormwater within the basin. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.070 Best management practices.

“Best management practices” or “BMPs” means any schedule of activities, prohibitions of practices, maintenance procedure or structural and/or managerial practice approved by King County that, when used singly or in combination, prevents or reduces the release of pollutants and other adverse impacts to surface water, stormwater and groundwater. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.080 City.

“City” means City of Sammamish, Washington, or, as indicated by the context, may mean any official, officer, employee or agency representing the City in the discharge of his or her duties. (Ord. O2017-452 § 1 (Att. A); Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.090 Closed depression.

“Closed depression” means an area greater than 5,000 square feet at overflow elevation that is low-lying and that has no or such a limited surface water outlet that the area acts as a stormwater retention facility. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.100 Clean Water Act.

“Clean Water Act” means 33 U.S.C. 1251 et seq., as amended. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.110 Construct or modify.

“Construct or modify” means to install a new drainage pipe or ditch or make improvements to an existing drainage pipe or ditch, for purposes other than maintenance, that either serves to concentrate previously unconcentrated surface and stormwater runoff or serves to increase, decrease or redirect the conveyance of surface and stormwater runoff. “Construct or modify” does not include installation or maintenance of a driveway culvert installed as part of a single-family residential building permit. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.120 Conveyance system.

“Conveyance system” means the drainage facilities and features, both natural and constructed, that provide for the collection and transport of surface water or stormwater runoff. The natural elements of the conveyance system include swales and small drainage courses, streams, rivers, lakes and wetlands. The constructed elements of the conveyance system include gutters, ditches, pipes, catch basins, channels and most flow control and water quality treatment facilities. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.130 Department.

“Department” means the department of public works or its successor. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.140 Development.

“Development” means any activity that requires a permit or approval, including, but not limited to, a building permit, grading permit, shoreline substantial development permit, conditional use permit, special use permit, zoning variance or reclassification, subdivision, short subdivision, urban planned development, binding site plan, site development permit or right-of-way use permit. “Development” does not include a Class I, II, III or IV-S forest practice conducted in accordance with Chapter 76.09 RCW and WAC Title 222 or a Class IV-G nonconversion forest practice, as defined in Chapter 21A.15 SMC, conducted in accordance with Chapter 76.09 RCW and WAC Title 222 and a county-approved forest management plan. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.150 Developed parcel.

“Developed parcel” means any parcel of real property altered from the natural state by the construction, creation or addition of impervious surfaces. (Ord. O2017-452 § 1 (Att. A); Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.160 Director.

“Director” means the director of the City of Sammamish department of public works, other department directors specified in enforcement procedures established in accordance with the Sammamish Municipal Code, or any designee of those directors. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.170 Division.

“Division” means the department of public works, engineering division, or its successor agency. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.180 Discharge.

“Discharge” means runoff, excluding off-site flows, leaving the proposed development through overland flow, built conveyance systems, or infiltration facilities. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.190 Drainage.

“Drainage” means the collection, conveyance, containment or discharge, or any combination thereof, of surface and stormwater runoff. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.200 Drainage facility.

“Drainage facility” means a constructed or engineered stream, lake, wetland, or closed depression, or a pipe, channel, ditch, gutter, flow control facility, flow control best management practice, water quality facility, erosion and sediment control facility, and any other structure and appurtenance that provide for drainage. (Ord. O2017-452 § 1 (Att. A); Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.210 Drainage review.

“Drainage review” means an evaluation by City staff of a proposed project’s compliance with the drainage requirements in the Surface Water Design Manual. The types of drainage review include: simplified drainage review, targeted drainage review, directed drainage review, full drainage review and large project drainage review. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.220 Effective impervious surface.

“Effective impervious surface” means those impervious surfaces that are connected via sheet flow or discrete conveyance to a drainage system. Impervious surfaces are considered ineffective if: (1) the runoff is fully dispersed as described in Appendix C of the Surface Water Design Manual; (2) residential roof runoff is infiltrated in accordance with the full infiltration BMP described in the Surface Water Design Manual; or (3) approved continuous runoff modeling methods indicate that the entire runoff file is infiltrated. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.225 Equivalent service unit (ESU).

“Equivalent service unit (ESU)” means a configuration of impervious surface estimated to contribute an amount of runoff to the City’s stormwater management system which is approximately equal to that created by the average single-family residential developed parcel in the City. (Ord. O2017-452 § 1 (Att. A))

13.10.230 Erosion and sediment control.

“Erosion and sediment control” means any temporary or permanent measures taken to reduce erosion, control siltation and sedimentation and ensure that sediment-laden water does not leave the site or enter into wetlands or aquatic areas. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.240 Farm management plan.

“Farm management plan” means a comprehensive site-specific plan developed by the farm owner in cooperation with the King Conservation District taking into consideration the land owners’ objectives while protecting water quality and related natural resources. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.250 Financial guarantee.

“Financial guarantee” means a form of financial security posted to do one or more of the following: ensure timely and proper completion of improvements; ensure compliance with the Sammamish Municipal Code; or provide secured warranty of materials, workmanship of improvements and design. “Financial guarantees” include assignments of funds, cash deposit, surety bonds or other forms of financial security acceptable to the director. “Performance guarantee,” “maintenance guarantee” and “defect guarantee” are considered subcategories of financial guarantee. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.260 Flood hazard reduction plan.

“Flood hazard reduction plan” means a plan and all implementing programs, regulations and procedures including, but not limited to, capital projects, public education activities and enforcement programs for reduction of flood hazards and prepared in accordance with RCW 86.12.200. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.270 Flow control best management practice.

“Flow control best management practice” means a small-scale drainage facility or feature that is part of a development site strategy to use processes such as infiltration, dispersion, storage, evaporation, transpiration, forest retention, and reduced impervious surface footprint to mimic predeveloped hydrology and minimize stormwater runoff. “Flow control best management practice” includes the methods and designs specified in the Surface Water Design Manual. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.280 Flow control facility.

“Flow control facility” means a drainage facility designed to mitigate the impacts of increased surface and stormwater runoff generated by site development in accordance with the drainage requirements in this title. A flow control facility is designed either to hold water for a considerable length of time and then release it by any combination of evaporation, plant transpiration or infiltration into the ground or to hold runoff for a short period of time and then release it to the conveyance system. (Ord. O2017-452 § 1 (Att. A); Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.290 Forest practices.

“Forest practices” means any activity conducted on or directly pertaining to forest land and relating to growing, harvesting, or processing timber, as defined in Chapter 222-16 WAC. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.300 Full drainage review.

“Full drainage review” means the evaluation required by Chapter 13.20 SMC for any proposed project, unless the project is subject to simplified drainage review, targeted drainage review, direct drainage review or large project drainage review, that:

(1) Would result in 2,000 square feet or more of new plus replaced impervious surface; or

(2) Would result in 7,000 square feet or more of land disturbing activity. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.310 Groundwater.

“Groundwater” means all waters that exist beneath the land surface or beneath the bed of any surface water. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.320 High-use site.

“High-use site” means a commercial, industrial or road intersection site that generates a higher than average number of vehicle turnovers or has other characteristics that generate the potential for chronic oil accumulation. “High-use site” includes:

(1) A commercial or industrial site subject to:

(a) An expected daily traffic count greater than 100 vehicles per 1,000 square feet of gross building area;

(b) Petroleum storage or transfer in excess of 1,500 gallons per year, not including routine fuel oil storage or transfer; or

(c) Use, storage or maintenance of a fleet of 25 or more diesel vehicles each weighing over 10 tons; or

(2) A road intersection with average daily traffic counts of 25,000 vehicles or more on the main roadway and 15,000 or more vehicles on any intersecting roadway, excluding pedestrian or bicycle use improvement projects. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.330 Hydraulically connected.

“Hydraulically connected” means connected through surface flow or water features such as wetlands or lakes. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.340 Impervious surface.

“Impervious surface” means a hard surface area that either prevents or retards the entry of water into the soil mantle as under natural conditions before development; or that causes water to run off the surface in greater quantities or at an increased rate of flow compared to the flow present under natural conditions prior to development (see also “new impervious surface”). Common impervious surfaces include, but are not limited to, roofs, walkways, patios, driveways, parking lots, or storage areas, areas that are paved, graveled or made of packed or oiled earthen materials or other surfaces that similarly impede the natural infiltration of surface water or stormwater. For the purposes of applying the impervious surface thresholds and exemptions contained in the Surface Water Design Manual, permeable pavement, vegetated roofs, and pervious surfaces with underdrains designed to collect stormwater runoff are considered impervious surfaces while an open uncovered flow control or water quality facility is not. However, for the purposes of computing runoff, uncovered flow control or water quality facilities shall be modeled as impervious surfaces as specified in Chapter 3 of the Surface Water Design Manual. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.350 Improvement.

“Improvement” means a permanent, human-made, physical change to land or real property including, but not limited to, buildings, streets, driveways, sidewalks, crosswalks, parking lots, water mains, sanitary and storm sewers, drainage facilities and landscaping. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.360 Land disturbing activity.

“Land disturbing activity” means an activity that results in a change in the existing soil cover, both vegetative and nonvegetative, or to the existing soil topography. “Land disturbing activity” includes, but is not limited to, demolition, construction, clearing, grading, filling, excavation and compaction. “Land disturbing activity” does not include tilling conducted as part of agricultural practices, landscape maintenance or gardening. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.370 Land use code.

“Land use code” means restrictions on the type of development for a specific parcel of land as identified by records maintained by the City of Sammamish as modified or supplemented by information resulting from investigation by the division. Land use codes are preliminary indicators of the extent of impervious surface and are used in the initial analysis to assign an appropriate rate category for a specific parcel. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.380 Lake management plan.

“Lake management plan” means a plan describing the lake management recommendations and requirements adopted by public rule for managing water quality within individual lake basins. Adopted lake management plans are available from the department. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.390 Large project drainage review.

“Large project drainage review” means the evaluation required by Chapter 13.20 SMC for any proposed project that:

(1) Has an urban plan development land use designation in the Sammamish comprehensive plan land use map;

(2) Would, at full buildout of the project site, result in 50 acres or more of new impervious surface within a drainage subbasin or a number of subbasins hydraulically connected across subbasin boundaries; or

(3) Has a project site of 50 acres or more within a critical aquifer recharge area, as defined in SMC Title 21A. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.400 Licensed civil engineer.

“Licensed civil engineer” means a person registered with the state of Washington as a professional engineer in civil engineering. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.410 Maintenance.

“Maintenance” means those usual activities taken to prevent a decline, lapse or cessation in the use of currently serviceable structures, facilities, equipment or systems, if there is no expansion of the structure, facilities, equipment or system and there are no significant hydrologic impacts. “Maintenance” includes the repair or replacement of nonfunctional facilities or the replacement of existing structures with different types of structures, if the repair or replacement is required by one or more environmental permits or to meet current engineering standards and the functioning characteristics of the original facility or structure are not changed. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.415 Manager.

“Manager” means the City manager or designee. (Ord. O2017-452 § 1 (Att. A))

13.10.420 Master drainage plan.

“Master drainage plan” means a comprehensive drainage control plan for projects subject to large project drainage review and intended to prevent significant adverse impacts to surface water and groundwater, both on and off site. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.421 Municipal separate storm sewer systems.

“Municipal separate storm sewer systems” or “MS4” is a conveyance or system of conveyances that is owned by the City of Sammamish that discharges to waters of the U.S., designed or used to collect or convey stormwater (e.g., storm drains, pipes, ditches), not a combined sewer, and not part of a sewage treatment plant, or publicly owned treatment works. (Ord. O2018-459 § 1 (Att. A))

13.10.430 National Pollutant Discharge Elimination System.

“National Pollutant Discharge Elimination System” or “NPDES” means the national program for controlling pollutants from point source discharges directly into waters of the United States under the Clean Water Act. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.440 National Pollutant Discharge Elimination System permit.

“National Pollutant Discharge Elimination System permit” means an authorization, license or equivalent control document issued by the Environmental Protection Agency or the Washington State Department of Ecology to implement the requirements of the NPDES program. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.450 Native vegetated surface.

“Native vegetated surface” means a surface in which the soil conditions, ground cover and species of vegetation are like those of the original native condition for the site, as more specifically set forth in the Surface Water Design Manual. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.460 Natural discharge location.

“Natural discharge location” means the location where runoff leaves the project site under existing site conditions as defined in the Surface Water Design Manual. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.470 Natural surface water drainage system.

“Natural surface water drainage system” means such landscape features as rivers, streams, lakes and wetlands. This system circulates water in a complex hydrological cycle. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.480 New impervious surface.

“New impervious surface” means the creation of a hard or compacted surface such as roofs, pavement, gravel or dirt or the addition of a more compacted surface such as the paving of existing dirt or gravel. Permeable pavement and vegetated roofs are considered new impervious surface for purposes of determining whether the thresholds for application of minimum requirements are exceeded, as are lawns, landscaping, sports fields, golf courses, and other areas that have modified runoff characteristics resulting from the addition of underdrains designed to collect stormwater runoff. Open, uncovered retention/detention facilities shall not be considered impervious surfaces for purposes of determining whether the thresholds for application of minimum requirements are exceeded. Open, uncovered retention/detention facilities shall be considered impervious surfaces for purposes of runoff modeling. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.490 New pervious surface.

“New pervious surface” means the conversion of a native vegetated surface or other native surface to a nonnative pervious surface, including, but not limited to, pasture land, grassland, cultivated land, lawn, landscaping or bare soil or any alteration of existing nonnative pervious surface that results in increased surface and stormwater runoff as defined in the Surface Water Design Manual. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.500 Open space.

“Open space” means any parcel, property or portion thereof classified for current use taxation under Chapter 20.36 KCC and Chapter 84.34 RCW, or for which the development rights have been sold to King County under Chapter 26.04 KCC. This definition includes lands which have been classified as open space, agricultural or timber lands under criteria contained in Chapter 20.36 KCC and Chapter 84.34 RCW. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.510 Parcel.

“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 lot number by the King County assessor. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.520 Person.

“Person” means an individual and his or her agent or assign, municipality, political subdivision, government agency, partnership, corporation, business or any other entity. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.525 Pervious surface.

“Pervious surface” means any surface material that allows stormwater to infiltrate into the ground. Examples include lawn, landscape, pasture, and native vegetation areas. Note: For purposes of threshold determination and runoff volume modeling for detention and treatment, vegetated roofs and permeable pavements are to be considered impervious surfaces along with lawns, landscaping, sports fields, golf courses, and other areas that have modified runoff characteristics resulting from the addition of underdrains. (Ord. O2016-428 § 4 (Att. B))

13.10.530 Pollution-generating impervious surface.

“Pollution-generating impervious surface” means an impervious surface considered to be a significant source of pollutants in surface and stormwater runoff. “Pollution-generating impervious surface” includes those surfaces subject to vehicular use or storage of erodible or leachable materials, wastes or chemicals and that receive direct rainfall or the run-on or blow-in of rainfall. A covered parking area would be included if runoff from uphill could regularly run through it or if rainfall could regularly blow in and wet the pavement surface. Metal roofs are also considered pollution-generating impervious surfaces unless they are treated to prevent leaching. Pollution-generating impervious surfaces include roofs that are exposed to the venting of significant amounts of dusts, mists, or fumes from manufacturing, commercial, or other indoor activities. They also include vegetated roofs exposed to pesticides, fertilizers, or loss of soil. Lawns, landscaping, sports fields, golf courses, and other areas that have modified runoff characteristics resulting from the addition of underdrains that have the pollution-generating characteristics described under the “pollution-generating pervious surface” definition are also considered PGIS. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.540 Pollution-generating pervious surface.

“Pollution-generating pervious surface” means a nonimpervious surface considered to be a significant source of pollutants in surface and stormwater runoff. “Pollution-generating pervious surfaces” include surfaces subject to the use of pesticides and fertilizers, to the use or storage of erodible or leachable materials, wastes or chemicals or to the loss of soil. “Pollution-generating pervious surface” includes, but is not limited to, the lawn and landscaped areas of a residential or commercial site, golf course, park, sports field and City-standard grassed modular grid pavement. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.550 Project.

“Project” means any proposed action to alter or develop a site that may also require drainage review. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.560 Project site.

“Project site” means the portion of a site and any off-site areas subject to proposed project activities, alterations and improvements including those required by this chapter. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.570 Rate category.

“Rate category” means the classification in this chapter given to a parcel in the service area based upon the type of land use on the parcel and the percentage of impervious surface area contained on the parcel. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.580 Redevelopment project.

“Redevelopment project” means a project that proposes to add, replace or modify impervious surface for purposes other than a residential subdivision or maintenance on a site that:

(1) Is already substantially developed in a manner that is consistent with its current zoning or with a legal nonconforming use; or

(2) Has an existing impervious surface coverage of 35 percent or more. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.590 Replaced impervious surface.

“Replaced impervious surface” means an existing impervious surface proposed to be removed and reestablished as impervious surface, excluding impervious surface removed for the sole purpose of installing utilities or performing maintenance on underground infrastructure. For structures, “removed” means the removal of buildings down to the foundation. For other impervious surfaces, “removed” means the removal down to base course or bare soil. It does not include the removal of pavement material through grinding or other surface modification unless the entire layer of PCC or AC is removed. Replaced impervious surface also includes impervious surface that is moved from one location to another on the project site where the following two conditions are met: (1) the area from which the impervious surface is moved from will be restored to the same or better runoff discharge characteristics as the area being covered by the moved impervious surface, and (2) impervious surface at the new location is either designated as non- pollution-generating or the pollution-generating characteristics remain unchanged compared to that of the original location. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.600 Residence.

“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. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.610 Residential parcel.

“Residential parcel” means any parcel which contains no more than three residences or three residential units which are within a single structure and is used primarily for residential purposes. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.615 Road.

“Road” means an urban right-of-way, paving and associated improvements which enable motor vehicles, transit vehicles, bicycles and pedestrians to travel between destinations, and afford the principal means of access to abutting property, including avenue, place, way, drive, lane, boulevard, highway, street, and other thoroughfare, except an alley. (Ord. O2017-452 § 1 (Att. A))

13.10.620 Runoff.

“Runoff” means that portion of water originating from rainfall and other precipitation that flows over the surface or just below the surface from where it fell and is found in drainage facilities, rivers, streams, springs, seeps, ponds, lakes, wetlands and shallow groundwater as well as on ground surfaces. For the purpose of this definition, “groundwater” means all waters that exist beneath the land surface or beneath the bed of any stream, lake or reservoir, or other body of surface water, whatever may be the geological formation or structure in which such water stands or flows, percolates or otherwise moves. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.630 Salmon conservation plan.

“Salmon conservation plan” means a plan and all implementing regulations and procedures including, but not limited to, land use management adopted by ordinance, capital projects, public education activities and enforcement programs for conservation and recovery of salmon within a water resource inventory area designated by the state under WAC 173-500-040. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.640 Shared facility.

“Shared facility” means a drainage facility designed to meet one or more of the requirements of Chapter 13.20 SMC for two or more separate projects contained within a basin. Shared facilities usually include shared financial commitments for those drainage facilities. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.650 Service area.

“Service area” means the incorporated City of Sammamish. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.651 Service charges.

“Service charges” means the surface water utility fee in an amount to be determined by applying the appropriate rate to a particular parcel of real property based upon factors established by this title. (Ord. O2017-452 § 1 (Att. A))

13.10.655 Simplified drainage review.

“Simplified drainage review” means the drainage review for a proposed single-family residential project or agricultural project that: results in less than 5,000 square feet of new plus replaced pollution-generating impervious surface, results in less than three-quarters acre of pollution-generating pervious surface, limits target impervious and pervious surface as specified in the Surface Water Design Manual, and meets the simplified drainage requirements specified in Appendix C of the Surface Water Design Manual, including flow control best management practices, erosion and sediment control measures, and drainage plan submittal requirements. (Ord. O2016-428 § 4 (Att. B))

13.10.656 Single-family residence.

“Single-family residence” means a residential structure accommodating one dwelling unit, including duplex units and mobile homes, as defined by the City land use codes. (Ord. O2017-452 § 1 (Att. A))

13.10.660 Site.

“Site” means a single parcel, or two or more contiguous parcels that are under common ownership or documented legal control, used as a single parcel for a proposed project for purposes of applying for authority from the City of Sammamish to carry out a proposed project. For projects located primarily within dedicated rights-of-way, “site” includes the entire width of right-of-way subject to improvements proposed by the project. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.670 Small project drainage review.

Repealed by Ord. O2016-428. (Ord. O2011-304 § 1 (Att. A))

13.10.680 Source control BMP.

“Source control BMP” means a BMP intended to prevent contaminants from entering surface and stormwater or groundwater including the modification of processes to eliminate the production or use of contaminants. “Source control BMPs” can be either structural or nonstructural. Structural source control BMPs involve the construction of a physical structure on site, or other type of physical modification to a site. An example of a structural source control BMP is building a covered storage area. A nonstructural source control BMP involves the modification or addition of managerial or behavioral practices. An example of a nonstructural source control BMP is using less toxic alternatives to current products or sweeping parking lots. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.690 State Waste Discharge Permit.

“State Waste Discharge Permit” means an authorization, license, or equivalent control document issued by the Washington State Department of Ecology in accordance with Chapter 173-216 WAC. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.700 Stormwater compliance plan.

“Stormwater compliance plan” means a plan or study and all regulations and procedures that have been adopted by the City to implement the plan or study, including, but not limited to, capital projects, public education activities and enforcement programs for managing stormwater quantity and quality discharged from the City’s municipal separate storm sewer system in compliance with the National Pollutant Discharge Elimination System permit program under the Clean Water Act. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.710 Stormwater plan.

“Stormwater plan” means a City of Sammamish ordinance specifying the stormwater control facilities that will be funded by a bond issue. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.720 Stormwater Pollution Prevention Manual.

“Stormwater Pollution Prevention Manual” means the manual adopted in accordance with Chapter 2.55 SMC, and supporting documentation referenced or incorporated in the manual, describing best management practices and procedures for existing facilities and existing and new activities not covered by the Surface Water Design Manual. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.730 Subbasin.

“Subbasin” means a geographic area that:

(1) Drains to a stream or water body named and noted on common maps; and

(2) Is contained within the basin of the stream or water body. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.740 Surface and stormwater.

“Surface and stormwater” means water originating from rainfall and other precipitation that is found on ground surfaces and in drainage facilities, rivers, streams, springs, seeps, ponds, lakes, wetlands, as well as shallow groundwater. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.750 Surface water utility.

“Surface water utility” means the services provided by the surface water management program, including but not limited to basin 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. (Ord. O2017-452 § 1 (Att. A); Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.760 Surface and stormwater management system.

“Surface and stormwater management system” means constructed drainage facilities and any natural surface water drainage features that do any combination of collection, storing, controlling, treating or conveying surface and stormwater. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.770 Surface Water Design Manual.

“Surface Water Design Manual” means the manual, and supporting documentation referenced or incorporated in the manual, describing surface and stormwater design and analysis requirements, procedures and guidance that has been formally adopted by rule under the procedures in Chapter 2.55 SMC. The Surface Water Design Manual is available from the department of public works or its successor agency. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.780 Surface water management fee protocols.

“Surface water management fee protocols” or “SWM fee protocols” means the surface water management fee standards and procedures that have been formally adopted by rule under the procedures specified in Chapter 2.55 SMC. The SWM fee protocols are available from the department of public works or its successor agency. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.790 Treatment BMP.

“Treatment BMP” means a BMP intended to remove contaminants once they are already contained in stormwater. Examples of treatment BMPs include oil/water separators, biofiltration swales and wetponds. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.800 Targeted drainage review.

“Targeted drainage review” means an abbreviated evaluation required by Chapter 13.20 SMC for certain types of proposed projects that are not subject to full or large project drainage review. Targeted drainage review may be required for some projects in simplified drainage review. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.810 Undeveloped parcel.

“Undeveloped parcel” means any parcel of real property which has not been altered from its natural state by the construction, creation or addition of impervious surface. (Ord. O2017-452 § 1 (Att. A); Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))

13.10.815 Unit rate.

“Unit rate” means the dollar amount charged per ESU. (Ord. O2017-452 § 1 (Att. A))

13.10.820 Water quality facility.

“Water quality facility” means a drainage facility designed to mitigate the impacts of increased pollutants in stormwater runoff generated by site development. A water quality facility uses processes that include but are not limited to settling, filtration, adsorption, and absorption to decrease pollutant concentrations and loadings in stormwater runoff. (Ord. O2016-428 § 4 (Att. B); Ord. O2011-304 § 1 (Att. A))