Active fault—A fault that is considered likely to undergo renewed movement within a period of concern to humans. Faults are commonly considered to be active if the fault has moved one or more times in the last ten thousand (10,000) years, but faults may also be considered active in some cases if movement has occurred in the last five hundred thousand (500,000) years.

Adaptive management—Adaptive management relies on scientific methods to evaluate how well regulatory and nonregulatory actions protect the critical area. An adaptive management program is a formal and deliberate scientific approach to taking action and obtaining information in the face of uncertainty.

Adjacent—Immediately adjoining (in contact with the boundary of the influence area) or within a distance that is less than that needed to separate activities from critical areas to ensure protection of the functions and values of the critical areas. Adjacent shall mean any activity or development located:

Advance mitigation—Mitigation of an anticipated critical area impact or hazard completed according to an approved report or other applicable information and prior to site development.

Agricultural land—Land primarily devoted to the commercial production of horticultural, viticultural, floricultural, dairy, apiary, or animal products or of berries, grain, hay, straw, turf, seed, Christmas trees not subject to the excise tax imposed by RCW 84.33.100 through 84.33.140, or livestock, and or that has been designated as long-term commercial significance for agricultural production.

Alteration—Any human-induced change in an existing condition of a critical area or its buffer. Alterations include, but are not limited to, grading, filling, channelizing, dredging, clearing (vegetation), construction, compaction, excavation, or any other activity that changes the character of the critical area.

Applicant—A person who files an application for a permit under this chapter and who is either the owner of the land on which that proposed activity would be located, a contract purchaser, or the authorized agent of such a person.

Aquifer—A geological formation, group of formations, or part of a formation that is capable of yielding a significant amount of water to a well or spring.

Area of shallow flooding—An area designated AO or AH zone on the flood insurance map(s). The base flood depths range from one (1) to three (3) feet; a clearly defined channel does not exist; the path of flooding is unpredictable and indeterminate; and velocity flow may be evident. AO is characterized as sheet flow and AH indicates ponding.

Base flood—A flood event having a one (1) percent chance of being equaled or exceeded in any given year, also referred to as the one hundred (100) year flood. Designations of base flood areas on flood insurance map(s) always include the letters A or V.

Best available science—Current scientific information used in the process to designate, protect, or restore critical areas that is derived from a valid scientific process as defined by WAC 365-195-900 through 365-195-925. Sources of best available science are included in “Citations of Recommended Sources of Best Available Science for Designating and Protecting Critical Areas” published by the state Office of Community Development.

Best management practices (BMPs)—Conservation practices or systems of practices and management measures that:

The city of Aberdeen shall monitor the application of best management practices to ensure that the standards and policies of this chapter are adhered to.

Biodiversity—The variety of animal and plant life and its ecological processes and interconnections—represented by the richness of ecological systems and the life that depends on them, including human life and economies.

Breakaway wall—A wall that is not part of the structural support of the building and is intended through its design and construction to collapse under specific lateral loading forces, without causing damage to the elevated portion of the building or supporting foundation system.

Buffer or buffer zone—An area contiguous to and that protects a critical habitat that is required for the continued maintenance, functioning, and/or structural stability of a critical area.

Compensation project—Actions necessary to replace project-induced critical area and buffer losses, including land acquisition, planning, construction plans, monitoring, and contingency actions.

Compensatory mitigation—Replacing project-induced critical wetland habitat losses or impacts, and includes, but is not limited to, the following:

Conservation easement—A legal agreement that the property owner enters into to restrict uses of the land. Such restrictions can include, but are not limited to, passive recreation uses such as trails or scientific uses and fences or other barriers to protect habitat. The easement is recorded on a property deed, runs with the land, and is legally binding on all present and future owners of the property, therefore providing permanent or long-term protection.

Critical aquifer recharge area (CARAs)—Areas that are identified in WAC 365-190-080(2) that are determined to have a critical recharging effect on aquifers used for potable water, including areas where an aquifer that is a source of drinking water is vulnerable to contamination that would affect the potability of the water, or is susceptible to reduced recharge.

Critical area tract—Land held in private ownership and retained in an open condition in perpetuity for the protection of critical areas. Lands within this type of dedication may include, but are not limited to, portions and combinations of forest habitats, grasslands, shrub steppe, on-site watersheds, one hundred (100) year floodplains, shorelines or shorelines of statewide significance, riparian areas, and wetlands.

Critical areas—Critical areas include any of the following areas or ecosystems: critical aquifer recharge areas, fish and wildlife habitat conservation areas, frequently flooded areas, geologically hazardous areas, and wetlands as defined in Chapter 36.70A RCW and this chapter. Aberdeen does not currently have any critical aquifer recharge areas.

Critical facility—A facility for which even a slight chance of flooding, inundation, or impact from a hazard event might be too great. Critical facilities include, but are not limited to, schools; nursing homes; hospitals; police, fire and emergency response installations; and installations that produce, use, or store hazardous materials or hazardous waste.

Critical species—All animal and plant species listed by the state or federal government as threatened or endangered.

Cumulative impacts or effects—The combined, incremental effects of human activity on ecological or critical areas functions and values. Cumulative impacts result when the effects of an action are added to or interact with other effects in a particular place and within a particular time. It is the combination of these effects, and any resulting environmental degradation, that should be the focus of cumulative impact analysis and changes to policies and permitting decisions.

Developable area—A site or portion of a site that may be utilized as the location of development, in accordance with the rules of this chapter.

Development—Any activity upon the land consisting of construction or alteration of structures; earth movement; dredging; dumping; grading; filling; mining; removal of any sand, gravel, or minerals; driving of piles; drilling operations; bulkheading; clearing of vegetation; or other land disturbance. Development includes the storage or use of equipment or materials inconsistent with the existing use. Development also includes approvals issued by the city of Aberdeen that binds land to specific patterns of use, including, but not limited to, subdivisions, short subdivisions, zone changes, conditional use permits, and binding site plans. Development activity does not include the following activities:

Development permit—Any permit issued by the city of Aberdeen, or other authorized agency, for construction, land use, or the alteration of land.

Director—The director of the city of Aberdeen community development department, or other city staff granted by the director the authority to act on behalf of the director.

Eco-connectivity—Eco-connectivity is a physical feature of the land as well as a functional one. It is the geo-physical connection between natural habitat areas that allows fish and animals to move between feeding, reproductive, rearing, and resting areas. The functional connection is dependent on the physical connection.

Elevated building—A building that has no basement and its lowest elevated floor is raised above ground level by foundation walls, shear walls, posts, piers, pilings, or columns.

Emergent wetland—A wetland with at least thirty (30) percent of the surface area covered by erect, rooted, herbaceous vegetation extending above the water surface as the uppermost vegetative stratum.

Erosion—The process whereby wind, rain, water, and other natural agents mobilize and transport particles.

Erosion hazard areas—Are those areas containing soils which, according to the United States Department of Agriculture Natural Resources Conservation Service Soil Survey Program, may experience significant erosion. Erosion hazard areas also include coastal erosion-prone areas and channel migration zones.

Estuary—The zero-gradient sector of a watercourse where it flows into a standing body of water together with associated natural wetlands; tidal flows reverse flow in the wetland twice daily, determining its upstream limit. It is characterized by low bank channels (distributaries) branching off the main stream to form a broad, near-level delta; bank, bed and delta materials are silt and clay, banks are stable, vegetation ranges from marsh to forest, and water is usually brackish due to daily mixing and layering of fresh and salt water.

Exotic—Any species of plants or animals, which are (not listed on the state plant list) foreign to the planning area.

Extreme slope hazard areas—Those areas with pre-development slope greater than thirty (30) percent.

Fish and wildlife habitat conservation areas—Are areas that serve a critical role in sustaining needed habitats and species for the functional integrity of the ecosystem, and which, if altered, may reduce the likelihood that the species will persist over the long term. These areas may include, but are not limited to, rare or vulnerable ecological systems, communities, and habitat or habitat elements including seasonal ranges, breeding habitat; winter range and movement corridors; and areas with high relative population density or species richness:

Fish habitat—Habitat that is used by fish at any life stage at any time of the year, including potential habitat likely to be used by fish that could be recovered by restoration or management and includes off-channel habitat.

Flood insurance map—The official map on which the Federal Insurance Administration has delineated the areas of special flood hazards and include the risk premium zones applicable to the community. Also known as “flood insurance rate map” or “FIRM.”

Flood insurance study—The official report provided by the Federal Insurance Administration that includes flood profiles, the flood boundary-floodway map, and the water surface elevation of the base flood.

Flood or flooding—A general and temporary condition of partial or complete inundation of normally dry land areas from the overflow of inland waters and/or the unusual and rapid accumulation of runoff of surface waters from any source.

Flood protection elevation—The elevation that is one (1) foot above the base flood elevation.

Flood resistant material—Materials designed to be resistant to the impacts associated with flooding and defined and described in detail in the Federal Emergency Management Agency’s Technical Bulletin No. 2-93, 1993 and FEMA publication FEMA-348, Protecting Building Utilities from Flood Damage.

Floodplain—The total land area adjoining a river, stream, watercourse or lake subject to inundation by the base flood.

Floodway—The channel of a river or other watercourse and the adjacent land area that must be reserved in order to discharge the base flood without cumulatively increasing the surface water elevation more than one (1) foot. Also known as the “zero rise floodway.”

Forested wetland—A wetland with at least thirty (30) percent of the surface area covered by woody vegetation greater than twenty (20) feet in height that is at least partially rooted within the wetland.

Formation—An assemblage of earth materials grouped together into a unit that is convenient for description or mapping.

Formation, confining—The relatively impermeable formation immediately overlying a confined aquifer.

Frequently flooded areas—Are lands in the floodplain subject to at least a one (1) percent or greater chance of flooding in any given year, or within areas subject to flooding due to high ground water and those lands that provide important flood storage, conveyance and attenuation functions, as determined by the director in accordance with WAC 365-190-080(3). Frequently flooded areas perform important hydrologic functions and may present a risk to persons and property. Classifications of frequently flooded areas include, at a minimum, the one hundred (100) year floodplain designations of the Federal Emergency Management Agency and the National Flood Insurance Program.

Functions and values—The beneficial roles served by critical areas including, but not limited to, water quality protection and enhancement, fish and wildlife habitat, food chain support, flood storage, conveyance and attenuation, ground water recharge and discharge, erosion control, wave attenuation, protection from hazards, historical and archaeological and aesthetic value protection, and recreation. These beneficial roles are not listed in order of priority.

Geologically hazardous areas—Areas that may not be suited to development consistent with public health, safety or environmental standards because of their susceptibility to erosion, sliding, earthquake, or other geological events as designated by WAC 365-190-080(4). Types of geologically hazardous areas include: erosion, landslide, seismic, mine, and volcanic hazards.

Ground water—Water in a saturated zone or stratum beneath the surface of land or a surface water body.

Ground water management area—A specific geographic area or subarea designated pursuant to Chapter 173-100 WAC for which a ground water management program is required.

Ground water management program—A comprehensive program designed to protect ground water quality, to ensure ground water quantity, and to provide for efficient management of water resources while recognizing existing ground water rights and meeting future needs consistent with local and state objectives, policies, and authorities within a designated ground water management area or subarea and developed pursuant to Chapter 173-100 WAC.

Growth Management Act—Chapter 36.70A RCW.

Habitat conservation areas—Areas designated as fish and wildlife habitat conservation areas.

Habitats of local importance—These areas include a seasonal range or habitat element with which a given species has a primary association, and which, if altered, may reduce the likelihood that the species will maintain and reproduce over the long term. These might include areas of high relative density or species richness, breeding habitat, winter range, and movement corridors. These might also include habitats that are of limited availability or high vulnerability to alterations such as cliffs, talus, and wetlands (WAC 365-190-030).

Hazard areas—Areas designated as frequently flooded areas or geologically hazardous areas due to potential for erosion, landslide, seismic activity, extreme slopes, or other geological condition.

Hazardous substances—Any liquid, solid, gas, or sludge, including any material, substance, product, commodity, or waste, regardless of quantity, that exhibits any of the physical, chemical, or biological properties described in WAC 173-303-090 or 173-303-100.

High intensity land use—Land uses which are associated with high levels of human disturbance or substantial habitat impacts including, but not limited to, commercial uses, industrial uses, and residential uses with five (5) or more units per acre.

High quality wetlands—Those wetlands that meet the following criteria:

Historic condition—Condition of the land, including flora, fauna, soil, topography, and hydrology, that existed before the area and vicinity were developed or altered by human activity.

Hydraulic project approval (HPA)—A permit issued by the state Department of Fish and Wildlife for projects that affect the bed or flow of waters of the state in accordance with Chapter 77.55 RCW and Chapter 220-110 WAC.

Hydric soil—A soil that is saturated, flooded or ponded long enough during the growing season to develop anaerobic conditions in the upper part. The presence of hydric soil shall be determined following the methods described in the Washington State Wetland Identification and Delineation Manual.

Hydrologic soil groups—Soils grouped according to their runoff-producing characteristics under similar storm and cover conditions. Properties that influence runoff potential are depth to seasonally high water table, intake rate and permeability after prolonged wetting, and depth to a low permeable layer. Hydrologic soil groups are normally used in equations that estimate runoff from rainfall but can be used to estimate a rate of water transmission in soil. There are four (4) hydrologic soil groups:

Hydrophytic vegetation—Macrophytic plant life growing in water or on a substrate that is at least periodically deficient in oxygen as a result of excessive water content. The presence of hydrophytic vegetation shall be determined following the methods described in the Washington State Wetland Identification and Delineation Manual.

Hyporheic zone—The saturated zone located beneath and adjacent to streams that contains some portion of surface waters, serves as a filter for nutrients, and maintains water quality.

Impervious surface—A hard surface area that either prevents or retards the entry of water into the soil mantle as under natural conditions prior to development or that 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, rooftops, 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 impede the natural infiltration of stormwater.

In-kind compensation—Same species, habitat type, and function impacted. If the impacted habitat is disturbed, it means replacement with the natural habitat that would occur. It does not mean replacement “in-category.”

Infiltration—The downward entry of water into the immediate surface of soil.

Inter-rill—Inter-rills are areas subject to sheetwash.

Isolated wetlands—Those wetlands that are outside of and not contiguous to any one hundred (100) year floodplain of a lake, river or stream, and have no contiguous hydric soil or hydrophytic vegetation between the wetland and any surface water.

Joint Aquatic Resource Permits Application (JARPA)—A single application form that may be used to apply for hydraulic project approvals, shoreline management permits, approvals of exceedance of water quality standards, water quality certifications, Coast Guard bridge permits, Department of Natural Resources use authorization, and Army Corps of Engineers permits.

Land use, high intensity—See “High intensity land use.”

Land use, low intensity—See “Low intensity land use.”

Land use, moderate intensity—See “Moderate intensity land use.”

Landslide hazard areas—Are areas that are at risk of mass movement due to geologic landslide resulting from a combination of geologic, topographic, and hydrologic factors. These areas are typically susceptible to landslides because of a combination of factors including: bedrock, soil, slope gradient, slope aspect, geologic structure, ground water, or other factors.

Levee—A levee is a manmade structure, usually an earthen embankment, designed and constructed in accordance with sound engineering practices to contain, control, or divert the flow of water so as to provide protection from temporary flooding.

Long-term commercial significance—Includes the growing capacity, productivity, and soil composition of the land for long-term commercial production, in consideration with the land’s proximity to population areas, and the possibility of more intense uses of the land. (RCW 36.70A.030(10); WAC 365-190-030(11)).

Low intensity land use—Land uses which are associated with low levels of human disturbance or low habitat impacts, including, but not limited to, passive recreation uses, open space uses, and residential uses with four (4) or fewer units per acre.

Lowest floor—The lowest floor of the lowest enclosed area, including the basement. An unfinished or flood resistant enclosure, usable solely for parking of vehicles, building access, or storage in an area other than a basement area, is not considered a building’s lowest floor; provided, that such enclosure is not built so as to render the structure in violation of the applicable requirements of this chapter.

Manufactured home—A structure, transportable in one (1) or more sections, which is built on a permanent chassis and is designed for use with or without a permanent foundation when attached to the required utilities. The term “manufactured home” does not include a “recreational vehicle.”

Manufactured home park or subdivision—A parcel (or contiguous parcels) of land divided into two (2) or more manufactured home lots for rent or sale.

Minerals—Materials including gravel, sand, and valuable metallic substances. (RCW 36.70A.030(11); WAC 365-190-030(12)).

Mitigation—Avoiding, minimizing or compensating for adverse critical areas impacts. Mitigation, in the following order of preference, is:

Mitigation for individual actions may include a combination of the above measures.

Moderate intensity land use—Land uses which are associated with moderate levels of human disturbance or substantial habitat impacts including, but not limited to, low density residential (no more than one (1) home per five (5) acres), active recreation, and moderate agricultural land uses.

Monitoring—Evaluating the impacts of development proposals on the biological, hydrological, and geological elements of such systems and assessing the performance of required mitigation measures through the collection and analysis of data by various methods for the purpose of understanding and documenting changes in natural ecosystems and features and includes gathering baseline data.

Native growth habitat area—An area where native vegetation is preserved for the purpose of preventing harm to property and the environment, including, but not limited to, controlling surface water runoff and erosion, maintaining slope stability, buffering and protecting plants and animal habitat.

Native vegetation—Plant species that are indigenous to the area in question. Plants that are not listed in Chapter 16-750 WAC.

Natural waters—Waters, excluding water conveyance systems, that are artificially constructed and actively maintained for irrigation, or any waters of the state.

Nonconformity—A legally established existing use or legally constructed structure that is not in compliance with current regulations.

Nonindigenous—See “exotic.”

Off-site mitigation—To replace critical areas away from the site on which a critical area has been impacted.

On-site mitigation—On or adjacent to the project impact site or in the same stream reach, based on resource needs.

Ordinary high water mark (OHWM)—OHWM on all lakes, streams, and tidal water is that mark that will be found by examining the bed and banks and ascertaining where the presence and action of waters are so common and usual, and so long continued in all ordinary years, as to mark upon the soil a character distinct from that of the abutting upland, in respect to vegetation as that condition exists on June 1, 1971, as it may naturally change thereafter, or as it may change thereafter in accordance with permits issued by a local government or the department; provided, that in any area where the ordinary high water mark cannot be found, the ordinary high water mark adjoining salt water shall be the line of mean higher high tide and the ordinary high water mark adjoining fresh water shall be the line of mean high water (RCW 90.58.030).

Out-of-kind replacement—To replace critical areas with substitute critical areas whose functions and values do not closely approximate those destroyed or degraded. It does not refer to replacement “out-of-category.”

Permeability—The capacity of an aquifer or confining bed to transmit water. It is a property of the aquifer or confining bed and is independent of the force causing movement.

Porous soil types—Soils, as identified by the Natural Resources Conservation Service, U.S. Department of Agriculture, that contain voids, pores, interstices, or other openings which allow the passing of water.

Potable water—Water that is safe and palatable for human use.

Practical alternative—An alternative that is available and capable of being carried out after taking into consideration, cost, existing technology, and logistics in light of overall project purposes, and having fewer impacts to critical areas.

Primary association area—The area used on a regular basis by, is in close association with, or is necessary for the proper functioning of the habitat of a critical species. Regular basis means that the habitat area is normally, or usually known to contain a critical species, or based on known habitat requirements of the species, the area is likely to contain the critical species. Regular basis is species and population dependent. Species that exist in low numbers may be present infrequently yet rely on certain habitat types.

Priority habitat—Habitat type or elements with unique or significant value to one or more species as classified by the Department of Fish and Wildlife. A priority habitat may consist of a unique vegetation type or dominant plant species, a described successional stage, or a specific structural element (WAC 173-26-020(34)).

Project area—All areas within fifty (50) feet of the area proposed to be disturbed, altered, or used by the proposed activity or the construction of any proposed structures.

Qualified professional—A person with experience and training in the pertinent scientific discipline, and who is a qualified scientific expert with expertise appropriate for the relevant critical area subject in accordance with WAC 365-195-905(4). A qualified professional must have obtained a B.S. or B.A. or equivalent degree in biology, engineering, environmental studies, fisheries, geomorphology or related field, and two (2) years of related work experience.

Recharge—The process involved in the absorption and addition of water to ground water.

Reclaimed water—Municipal wastewater effluent that has been adequately and reliably treated so that it is suitable for beneficial use. Following treatment, it is no longer considered wastewater (treatment levels and water quality requirements are given in the water reclamation and reuse standards adopted by the state Departments of Ecology and Health).

Recreation vehicle—A vehicle that is:

Regulatory flood—A level of flooding that a regulatory agency’s design regulations apply to.

Repair or maintenance—An activity that restores the character, scope, size, and design of a serviceable area, structure, or land use to its previously authorized and undamaged condition. Activities that change the character, size, or scope of a project beyond the original design and drain, dredge, fill, flood, or otherwise alter critical areas are not included in this definition.

A. Active steps taken to restore damaged wetlands, streams, protected habitat, or their buffers to the functioning condition that existed prior to an unauthorized alteration.

B. Actions performed to reestablish structural and functional characteristics of the critical area that have been lost by alteration, past management activities, or catastrophic events.

Rills—Steep-sided channels resulting from accelerated erosion. A rill is generally a few inches deep and not wide enough to be an obstacle to farm machinery. Rill erosion tends to occur on slopes, particularly steep slopes with poor vegetative cover.

Riparian habitat—Any area adjacent to surface water which possesses elements of both aquatic and terrestrial ecosystems that mutually influence each other. The width of these areas extends from the OHWM to that portion of the terrestrial landscape that directly influences the aquatic ecosystem by providing shade, fine or large woody material, nutrients, organic and inorganic debris, terrestrial insects, or habitat for riparian-associated wildlife. It includes the entire extent of the floodplain and the extent of vegetation adapted to wet conditions as well as adjacent upland plant communities that directly influence aquatic ecosystem. Riparian habitat areas include those riparian areas severely altered or damaged due to human development activities.

River—See “Watercourse.”

Scientific process—A valid scientific process is one that produces reliable information useful in understanding the consequences of a decision. The characteristics of a valid scientific process are as follows:

Section 404 Permit—A permit issued by the Corps of Engineers for the placement of dredge or fill material or clearing in waters of the U.S., including wetlands, in accordance with 33 U.S.C. § 1344.

Seeps—A spot where water oozes from the earth, often forming the source of a small stream.

Seismic hazard areas—Are areas that are subject to severe risk of damage as a result of earthquake-induced ground shaking, slope failure, settlement, soil liquefaction, debris flows, lahars or tsunamis.

SEPA—Washington State Environmental Policy Act, Chapter 43.21C RCW .

Serviceable—Presently usable.

Shorelands or shoreland areas—Those lands extending landward for two hundred (200) feet in all directions as measured on a horizontal plane from the ordinary high water mark; floodways and contiguous floodplain areas landward two hundred (200) feet from such floodways; and all wetlands and river deltas associated with the streams, lakes, and tidal waters which are subject to the provisions of Chapter 90.58 RCW.

Shorelines—All of the water areas of the state as defined in RCW 90.58.030, including reservoirs and their associated shorelands, together with the lands underlying them except:

Shorelines of statewide significance—Those areas defined in RCW 90.58.030(2)(e).

Shorelines of the state—The total of all “shorelines,” as defined in RCW 90.58.030(2)(d), and “shorelines of statewide significance” within the state, as defined in RCW 90.58.030(2)(c).

Significant portion of its range—That portion of a species range likely to be essential to the long-term survival of the population in Washington.

Soil survey—The most recent soil survey for the local area or county by the Natural Resources Conservation Service, U.S. Department of Agriculture.

Special flood hazard areas—The land in the floodplain within an area subject to a one (1) percent or greater chance of flooding in any given year. Designations of special flood hazard areas on flood insurance map(s) always include the letters A or V.

Special protection areas—Aquifer recharge areas defined by WAC 173-200-090.

Species—Any group of animals classified as a species or subspecies as commonly accepted by the scientific community.

Species, endangered—Any fish or wildlife species that is threatened with extinction throughout all or a significant portion of its range and is listed by the state or federal government as an endangered species.

Species of local importance—Are those species of local concern due to their population status or their sensitivity to habitat alteration or that are game species.

Species, priority—Any fish or wildlife species requiring protective measures and/or management guidelines to ensure their persistence as genetically viable population levels as classified by the Department of Fish and Wildlife, including endangered, threatened, sensitive, candidate and monitor species, and those of recreational, commercial, or tribal importance.

Species, threatened—Any fish or wildlife species that is likely to become an endangered species within the foreseeable future throughout a significant portion of its range without cooperative management or removal of threats and is listed by the state or federal government as a threatened species.

Stream—See “Watercourse.”

Sub-drainage basin or subbasin—The drainage area of the highest order stream containing the subject property impact area. Stream order is the term used to define the position of a stream in the hierarchy of tributaries in the watershed. The smallest streams are the highest order (first order) tributaries. These are the upper watershed streams and have no tributaries of their own. When two (2) first order streams meet, they form a second order stream, and when two (2) second order streams meet they become a third order stream, and so on.

Substantial damage—Damage of any origin sustained by a structure whereby the cost of restoring the structure to its before damaged condition would equal or exceed fifty (50) percent of the market value of the structure before the damage occurred.

Substantial improvement—Any repair, reconstruction, or improvement of a structure, the cost of which equals or exceeds fifty (50) percent of the market value of the structure either: before the improvement or repair is started; or if the structure has been damaged and is being restored, before the damage occurred.

Take—To harass, harm, pursue, hunt, shoot, wound, kill, capture, or collect, or to attempt to engage in any such conduct.

Tsunami—A series of waves produced when a water of body is rapidly displaced, especially as ocean waves generated by submarine earth movement or volcanic eruption.

Unavoidable—Adverse impacts that remain after all appropriate and practicable avoidance and minimization have been achieved.

Volcanic hazard areas—Shall include areas subject to pyroclastic flows, lava flows and inundation by debris, lahars, mudflows or related flooding resulting from volcanic activity.

Vulnerability—The combined effect of susceptibility to contamination and the presence of potential contaminants.

Watercourse—Any portion of a channel, bed, bank, or bottom waterward of the ordinary high water line of waters of the state including areas in which fish may spawn, reside, or through which they may pass, and tributary waters with defined beds or banks, which influence the quality of fish habitat downstream. This definition includes watercourses that flow on an intermittent basis or which fluctuate in level during the year and applies to the entire bed of such watercourse whether or not the water is at peak level. This definition does not include irrigation ditches, canals, stormwater run-off devices, or other entirely artificial watercourses, except where they exist in a natural watercourse that has been altered by humans.

Water dependent—A use or portion of a use that cannot exist in a location that is not adjacent to the water, but is dependent on the water by reason of the intrinsic nature of its operations. A use that can be carried out only on, in, or adjacent to water. Examples of water dependent uses include ship cargo terminal loading areas; fishing; ferry and passenger terminals; barge loading, ship building, and dry docking facilities; marinas, moorage, and boat launching facilities; aquaculture; float plane operations; surface water intake; and sanitary sewer and storm drain outfalls.

Water resource inventory area (WRIA)—One (1) of sixty-two (62) watersheds in the state of Washington, each composed of the drainage areas of a stream or streams, as established in Chapter 173-500 WAC as it existed on January 1, 1997.

Water table—That surface in an unconfined aquifer at which the pressure is atmospheric. It is defined by the levels at which water stands in wells that penetrate the aquifer just far enough to hold standing water.

Water table aquifer—See “Aquifer, unconfined.”

Water typing system—Waters classified according to WAC 222-16-030 including the following: