A. For the purposes of this chapter, the following definitions shall apply:

1. “Accessibility” means that a building or structure can be independently used by people with a variety of disabilities.

2. “Adverse impact” means a condition that creates, imposes, aggravates, or leads to inadequate, unsafe, or unhealthy conditions on a site.

3. “Agricultural activities” means the normal actions associated with the production of crops such as plowing, cultivating, minor drainage, and harvesting; and/or raising or keeping of livestock, including operation and maintenance, and repair of farm and stock ponds, drainage ditches, irrigation systems, and normal operation, maintenance, and repair of existing serviceable agricultural structures, facilities, or improved areas.

4. “Alteration” means a human-induced action that changes the existing conditions of a critical area or its buffer and results in the modification of the existing topography, stability, vegetation, hydrology, wildlife or wildlife habitat.

5. “Alteration, structure” means a change, modification or adjustment.

6. “Anadromous fish” means fish whose life cycle includes time spent in both salt and fresh water.

7. “Applicant” means a person, corporation, or organization that files an application for a land use or development permit with the city and that is either the owner of the land on which that proposed activity would be located, or the authorized agent of such a person.

8. “Aquifer recharge protection area” means a portion of a development site comprised of native or equivalent vegetation in which existing vegetation, topography and supporting soils are free of development, uses or activities detrimental to the aquifer recharge of the total site area.

9. “Arborist” means an individual engaged in the profession of arboriculture who, through experience, education, and related training, possesses the competence to provide for or supervise the management of trees and other woody plants. Must be concurrently an International Society of Arboriculture (ISA) certified arborist to perform any role required of a certified arborist.

10. “Arborist, ISA certified” means an arborist holding a current International Society of Arboriculture (ISA) certified arborist credential.

11. “Arborist, tree risk assessment qualified (TRAQ)” means an arborist who has successfully completed the International Society of Arboriculture (ISA) TRAQ training course and assessment and holds a valid ISA TRAQ credential.

12. “Bank stabilization” means modification used for the purpose of preventing erosion, protecting channels, and retaining uplands.

13. “Biodiversity areas and corridors” means areas of habitat that are relatively important to various species of native fish and wildlife.

a. Biodiversity Areas.

i. The area has been identified as biologically diverse through a scientifically based assessment conducted over a landscape scale (e.g., ecoregion, county- or city-wide, watershed, etc.). Examples include but are not limited to WDFW local habitat assessments, Pierce County biodiversity network, and Spokane County’s wildlife corridors and landscape linkages; or

ii. The area is within a city or an urban growth area (UGA) and contains valuable fish or wildlife habitat and is mostly comprised of native vegetation. Relative to other vegetated areas in the same city or UGA, the mapped area is vertically diverse (e.g., multiple canopy layers, snags, or downed wood), horizontally diverse (e.g., contains a mosaic of native habitats), or supports a diverse community of species as identified by a qualified professional who has a degree in biology or closely related field and professional experience related to the habitats or species occurring in the biodiversity area. These areas may have more limited wildlife functions than other priority habitat areas due to the general nature and constraints of these sites in that they are often isolated or surrounded by highly urbanized lands.

b. Corridors. Corridors are areas of relatively undisturbed and unbroken tracts of vegetation that connect fish and wildlife habitat conservation areas, priority habitats, areas identified as biologically diverse, or valuable habitats within the city.

14. “Best available science” (BAS) means scientifically valid information derived in accordance with WAC 365-195-900 through 365-195-925, or as amended, that is used to develop and implement critical areas policies or regulations.

15. “Best management practices” (BMPs) means conservation practices or systems of practices and management measures that:

a. Control soil loss and protect water quality from degradation caused by nutrients, animal waste, toxins, and sediment;

b. Minimize adverse impacts to surface water and groundwater flow, and to the chemical, physical, and biological characteristics of critical areas;

c. Protect trees, vegetation and soils designated to be retained during and following site construction and use native plant species appropriate to the site for revegetation of disturbed areas; and

d. Provide standards for proper use of chemical herbicides within critical areas.

e. BMPs are defined by the United States Department of Agriculture, the State of Washington Department of Agriculture, the Washington State Department of Ecology, Washington State Department of Health, Kitsap conservation district, and other professional organizations.

16. “Bog” means a low-nutrient, acidic wetland with organic soils and characteristic bog plants, as described in Washington State Wetland Rating System for Western Washington: 2014 Update (Ecology Publication No. 14-06-29, October 2014).

17.  “Buffer” means a designated area contiguous to a wetland or stream intended to protect the wetland or stream and be an integral part of the wetland or stream ecosystem.

18. “Coppicing” means managing of strongly regenerative species of trees and shrubs by an initial heading cut (leaving a stump) and allowing new shoots to grow to maintain live roots. Shoots may be reduced to their point of origin at appropriate intervals of time without disturbing the resulting coppice head (stump).

19. “Critical aquifer recharge area” means areas with 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.

20. “Critical areas” means aquifer recharge areas, fish and wildlife habitat conservation areas, frequently flooded areas, geologically hazardous areas, and wetlands.

21. “Critical facilities” means facilities that are essential to the health and welfare of the community, including services that protect life and property. Such facilities include, but are not limited to, hospitals, emergency clinics, police and fire stations, emergency vehicle and equipment storage facilities, emergency operations centers, aviation control centers, and utility facilities such as sewage treatment plants and electric transmission substations.

22. “Critical habitat” means a habitat identified by U.S. Fish and Wildlife Service or the National Marine Fisheries Service as habitat necessary for survival of endangered or threatened species.

23. “Cutting, vegetation” means the removal of the main trunk or stem of a small tree for the purposes of controlling aggressive or weedy species.

24. “Designated centers” means those areas of the Island referred to as Winslow, Lynwood Center, Island Center, Rolling Bay, Day Road and Sportsman Triangle and shown on Figure LU-3 in the city’s 2017 comprehensive plan.

25. “Development” means any action that would require land use review or other approval from the city or other local, state or federal jurisdiction. “Development” includes, but is not limited to: land division; construction, reconstruction, structural alteration, relocation, or enlargement of any structure; clearing or grading; and changes to surface or groundwaters.

26. “Development area” means the area of land disturbing activity on a site.

27. “Director” means the director of the city’s planning and community development department or his/her designee.

28. “Educational or scientific activities” means controlled and/or supervised scientific activities or educational activities that are associated with an educational or scientific program that result in no adverse impacts to critical areas or their buffers.

29. “Engineering geologist” means a practicing engineering geologist who has at least four years of professional employment as an engineering geologist with experience in landslide evaluation, and a Washington State specialty license in engineering geology as specified in Chapter 18.220 RCW.

30. “Erosion hazard area” means those areas containing soils which, according to the United States Department of Agriculture Natural Resource Conservation Service Soil Survey Program, may experience significant erosion. Erosion hazard areas also include coastal erosion-prone areas and channel migration areas.

31. “Estuarine, wetland” means a vegetated wetland that is predominantly tidal, as described in Washington State Wetland Rating System for Western Washington: 2014 Update (Ecology Publication No. 14-06-29, October 2014).

32. “Existing development” means a development that was lawfully constructed, approved or established prior to the effective date of the ordinance codified in this chapter.

33. “Fish” means species of the vertebrate taxonomic groups Cephalospidomorphi and Osteichthyes.

34. “Fish and wildlife habitat conservation areas” means 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 and wildlife habitat conservation areas” does not include such artificial features or constructs as irrigation delivery systems, irrigation infrastructure, irrigation canals, or drainage ditches that lie within the boundaries of, and are maintained by, a port district or an irrigation district or company.

35. “Fish habitat” means habitat which is used by any fish at any life stage at any time of the year, including potential habitat likely to be used by fish which could be recovered by restoration or management and includes off-channel habitat.

36. “Fisheries biologist” means a person with experience and training in fisheries who is able to submit substantially correct reports on fish population surveys, stream surveys and other related data analyses of fisheries resources. “Substantially correct” means that technical or scientific errors, if any, are minor and do not delay or affect the site plan review process. Qualifications of a fisheries biologist include:

a. Either:

i. Certification by the American Fisheries Society; or

ii. Bachelor of science degree in fisheries or the biological sciences from an accredited institution and five years of professional fisheries experience; and

b. The prior successful completion of at least three habitat management plans.

37. “Frequently flooded areas” means lands subject to at least a one percent or greater chance of flooding in any given year, or within areas subject to flooding due to high groundwater. These areas include, but are not limited to, streams, lakes, coastal areas, wetlands and areas where high groundwater forms ponds on the ground surface. (See Chapter 15.16 BIMC, Flood Damage Prevention.)

38. “Functions and values” means the natural processes and beneficial roles performed or provided by critical areas including, but not limited to, water quality and quantity protection and enhancement, providing fish and wildlife habitat, supporting terrestrial and aquatic food chains, providing flood storage, conveyance and attenuation, groundwater recharge and discharge, erosion control, wave attenuation, protecting aesthetic value, and providing recreational and educational opportunities. These roles are not listed in order of priority.

39. “Geologically hazardous areas” means areas susceptible to significant erosion, sliding, or other geological events. They pose a threat to the health and safety of citizens when used as sites for incompatible commercial, residential or industrial development. Geologically hazardous areas include erosion hazard areas, landslide hazard areas, and seismic hazard areas.

40. “Geotechnical engineer” means a practicing geotechnical/civil engineer who has a valid Washington engineering license and a valid certificate of registration in civil engineering, at least four years of professional employment as a geotechnical engineer with experience in landslide evaluation, and appropriate training and experience as specified in Chapter 18.43 RCW.

41. “Habitat management plan” (HMP) means a report prepared by a professional wildlife biologist or fisheries biologist which discusses and evaluates critical fish and wildlife habitat functions and identifies and evaluates measures necessary to maintain, enhance and improve terrestrial and/or aquatic habitat on a proposed development site.

42. “Habitat of local importance” means an area representing either high quality habitat for native terrestrial or aquatic species or habitat which is of limited availability, highly vulnerable to alteration, or provides landscape connectivity which contributes to the integrity of the surrounding landscape and which is not adequately protected by other city, state or federal policies, laws, regulations, or nonregulatory tools that prevent degradation of the habitat or its associated species. These may include areas of high relative density or species richness, breeding habitat, winter range, and movement corridors such as breeding areas or human-made ponds.

43. “Hazard tree” means a tree that has significant structural defects that are likely to lead to failure and possibly cause injury or damage as identified in a report from an International Society of Arboriculture (ISA) tree risk assessment qualified (TRAQ) arborist. In the case of steep slopes, a hazard tree can also be a tree that is a hazard to stability of the slope, as determined by a geotechnical engineer.

44. “Hazardous substances” means any liquid, solid, gas, or sludge, including any material, substance, product, commodity, or waste, regardless of quantity, that exhibits any of the characteristics or criteria of hazardous waste as specified in RCW 70.105.010.

45. “Hedge” means a line of closely-spaced trees and/or shrubs intentionally planted and/or maintained along a property boundary or landscape border for privacy, screening, safety, or similar function, which typically requires ongoing pruning or shearing to maintain its intended function and/or reasonable use of nearby developed areas.

46. “Hydric soil” means soil which is saturated, flooded, or ponded long enough during the growing season to develop anaerobic conditions in the upper part.

47. “Hydrogeologist” means a practicing hydrogeologist who has at least four years of professional employment as a hydrogeologist with experience in the specific subject area in which they are providing a report, and a Washington specialty license in hydrogeology as specified in Chapter 18.220 RCW.

48. “Hydrophyte or hydrophytic vegetation” means plant life growing in water or on a substrate that is at least periodically deficient in oxygen as a result of excessive water content.

49. “Invasive/exotic species” means (a) nonnative (or alien) to the ecosystem under consideration and (b) whose introduction causes or is likely to cause economic or environmental harm or harm to human health, or as amended by the United States Department of Agriculture National Invasive Species Information Center (NISIC).

50. “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 a land disturbing activity. Vegetation maintenance practices are not considered land disturbing activity. Stormwater facility maintenance is not considered land disturbing activity if conducted according to established standards and procedures.

51. “Land divisions” means any division of land subject to the city’s subdivision design standards (Chapter 17.12 BIMC).

52. “Landslide hazard areas” means areas which are at risk of mass movement due to a combination of geologic, topographic, and hydrologic factors. Landslide hazard areas include the following:

a. Areas characterized by slopes greater than 15 percent having springs or groundwater seepage and having impermeable soils (typically silt and clay) overlain or frequently interbedded with permeable granular soils (predominantly sand and gravel);

b. Any area potentially unstable due to rapid stream incision or stream bank erosion;

c. Any area located on an alluvial fan, debris flow deposit, or in a debris flowpath, presently or potentially subject to impacts or inundation by debris flows or deposition of stream-transported sediments;

d. Any area with a slope of 40 percent or greater and with a vertical relief of 10 or more feet except areas composed of competent consolidated rock;

e. Any area designated or mapped as class U, UOS, or URS by the Department of Ecology Coastal Zone Atlas and/or mapped as a landslide or scarp on the USGS Surface Geology Map of Bainbridge Island (Haugerud, 2001).

53. “Landslide hazard area setback” means an area contiguous to a landslide hazard area sufficient in depth to meet the development standards set forth in BIMC 16.20.130 as determined by a geological hazards assessment prepared in accordance with BIMC 16.20.180, Critical area reports.

54. “Liquefaction” means a process in which a water-saturated soil, upon shaking, suddenly loses strength and behaves as a fluid.

55. “Low impact development (LID)” means a stormwater and land use management strategy that strives to mimic predisturbance hydrologic processes of infiltration, filtration, storage, evaporation and transpiration by emphasizing conservation, use of on-site natural features, site planning, and distributed stormwater management practices that are integrated into a project design.

56. “Low impact development best management practices (LID BMPs)” means distributed stormwater management practices, integrated into a project design, that emphasize predisturbance hydrologic processes of infiltration, filtration, storage, evaporation and transpiration. LID BMPs include, but are not limited to: bioretention, rain gardens, permeable pavements, roof downspout controls, dispersion, soil quality and depth, minimal excavation foundations, vegetated roofs, and water reuse.

57. “Native or equivalent vegetation” means species which are indigenous to the Puget Sound lowlands ecoregion; or a species that is equivalent in providing the same site-specific functional arrays as would the native species. “Functional arrays” may include forage, floodwater restraint, hiding habitat, or other physical or biologic roles in the ecosystem, that singly or in combination correspond to those of the native species. As with natives, the role of an equivalent species may vary depending on the site and its surrounding ecosystem. Invasive/exotic species shall not be considered equivalent species.

58. “Natural pruning system” means a pruning system intended to maintain a tree’s characteristic growth pattern and adaptations that may allow for changes in appearance to achieve certain specified objectives per ANSI A300 (Part 1 – 2017).

59. “No net loss” means the maintenance of the aggregate total of the city’s critical areas functions and values over time. The no net loss standard requires that the impacts of a proposed use and/or development, whether permitted or exempt from permit requirements, be identified and mitigated on a project-by-project basis, so that as development occurs critical areas functions and values stay the same.

60. “Normal maintenance” means those usual acts to prevent a decline, lapse or cessation from a lawfully established condition. Normal maintenance does not include:

a. Use of fertilizer or pesticide application in wetlands, fish and wildlife habitat conservation areas, or their buffers;

b. Redigging ditches in wetlands or their buffers to expand the depth or width beyond the original ditch dimensions;

c. Redigging existing drainage ditches to drain wetlands on lands not classified as existing and ongoing agriculture under BIMC 16.20.040 (Exemptions).  

61. “Normal repair” means activities to restore a structure or use to a state comparable to original condition, including but not limited to size, shape, configuration, location and external appearance, within a reasonable period after decay or partial destruction.

62. “Ordinary high water mark” means the mark on the shores of all waters, which will be found by examining the beds 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; provided, that in any area where the ordinary high water mark cannot be found, the ordinary high water mark adjoining freshwater shall be the line of mean high water.

63. “Pollarding” means a pruning system that maintains crown size by initial heading of branches on young trees, followed by removal of shoots to their point of origin at appropriate intervals without disturbing the resulting pollarding head.

64. “Pruning” means the selective removal of plant parts to achieve defined objectives.

65. “Pruning amount” means the quantity of plant parts removed at one pruning, expressed in terms of a number of branches or other parts removed, and/or percentage of the crown or buds removed on an entire tree or specific branches.

66. “Ravine” means a V-shaped landform generally having little to no floodplain and normally containing steep slopes, which is deeper than 10 vertical feet as measured from the centerline of the ravine to the top of the slope. Ravines are typically created by the wearing action of streams. The top of the slope is determined where there is a significant change in the slope to generally less than a 15 percent slope.

67. “Reasonable alternative” means an activity that could feasibly attain or approximate a proposal’s objectives, but at a lower environmental cost or decreased level of environmental degradation.

68. “Reasonable use exception (RUE)” is a means of relief that is available for a property that is encumbered to such an extent by critical areas and/or critical area buffers that application of this chapter would deny all reasonable use of the subject property, as further defined by the decision criteria of BIMC 16.20.080.

69. “Redevelopment” means, on a site that is already substantially developed (i.e., has 35 percent or more of existing impervious surface coverage), the creation or addition of impervious surfaces; the expansion of a building footprint or addition or replacement of a structure; construction, installation or expansion of a building or other structure; replacement of impervious surface that is not part of a routine maintenance activity; and land disturbing activities.

70. “Removal, vegetation” means to eliminate the presence or hazard of unwanted vegetation.

71. “Seismic hazard areas” means areas subject to severe risk of damage as a result of earthquake induced ground shaking, slope failure, settlement, soil liquefaction, debris flows, or tsunamis. The following areas are considered seismic hazard areas:

a. Seismic Landslide Hazard Areas. Slopes which are stable in nonearthquake periods, but fail and slide during ground shaking;

b. Liquefaction Hazard Areas. Areas of cohesionless, loose or soft saturated soils of low density in association with a shallow groundwater table that are subject to settlement and/or liquefaction from ground shaking; or

c. Fault Hazard Areas. Areas of known surface rupture or significant surface deformation as a result of an active fault movement, including 50 feet on either side.

72. “Shrub” means a woody perennial plant, usually with several stems that may be erect or close to the ground, generally smaller than a tree.

73. “Significant tree” means a deciduous tree greater than 12 inches in diameter at four feet high and an evergreen tree greater than 10 inches in diameter at four feet high.

74. “Site” means the entire lot, series of lots, or parcels on which a development is located or proposed to be located, including all contiguous undeveloped lots or parcels under common ownership.

75. “Species of local importance” means those species that are of local concern due to their population status or their sensitivity to habitat alteration.

76. “Streams” means those areas in the city of Bainbridge Island where the surface water flows are sufficient to produce a defined channel or bed. A defined channel or bed is an area which demonstrates clear evidence of the passage of water and includes but is not limited to bedrock channels, gravel beds, sand and silt beds, and defined-channel swales. The channel or bed need not contain water year round. This definition is not meant to include irrigation ditches, canals, storm or surface water runoff devices, or other artificial watercourses unless they are used by fish or used to convey streams naturally occurring prior to construction.

77. “Stream types” means a streams classification system based on fish usage and perennial or seasonal water regime as found in WAC 222-16-030 and meeting the standards listed below:

a. “Type F stream” means a stream that has fish habitat. Waters having the following characteristics are presumed to meet the physical criteria for fish use: Stream segments having a defined channel of two feet or greater within the bankfull width and having a gradient of 16 percent or less. Also, stream segments having a defined channel of two feet or greater within the bankfull width and having a gradient greater than 16 percent and less than or equal to 20 percent, and having greater than 50 acres in contributing basin size based on hydrographic boundaries.

b. “Type Np” means all segments of natural waters within the bankfull width of defined channels that are perennial nonfish habitat streams. “Perennial streams” are waters that do not go dry any time of a year of normal rainfall. However, for the purpose of water typing, Type Np waters include the intermittent dry portions of the perennial channel below the uppermost point of perennial flow.

c. “Type Ns” means all segments of natural waters within the bankfull width of the defined channels that are not Type S, F, or Np waters. These are seasonal, nonfish habitat streams in which surface flow is not present for at least some portion of a year of normal rainfall and are not located downstream from any stream reach that is a Type Np water. Ns waters must be physically connected by an aboveground channel system to marine waters, Type F, or Np waters.

78. “Tree” means a woody perennial plant with single or multiple trunks, which typically develop a mature size of over several inches diameter, and 10 or more feet in height.

79. “Upgrade” means activities that involve replacement of existing infrastructure, or replacing equipment with equipment that meets different operational standards and/or adds capacity to the system. Upgrades shall not include expansions or extensions of existing infrastructure.

80. “Wetland” means areas that are inundated or saturated by surface water or groundwater at a frequency and duration sufficient to support a prevalence of vegetation typically adapted for life in saturated soil conditions. Wetlands generally include, but are not limited to, swamps, estuaries, marshes, bogs, ponds less than 20 acres, including their submerged aquatic beds and similar areas. Wetlands do not include those artificial wetlands intentionally created from nonwetland sites, including, but not limited to, irrigation and drainage ditches, grass-lined swales, canals, stormwater facilities, wastewater treatment facilities, farm ponds, and landscape amenities, or those wetlands created after July 1, 1990, that were unintentionally created as a result of the construction of a road, street, or highway. “Wetlands” include those legally established artificial wetlands intentionally created from nonwetland areas to mitigate the conversion of wetlands.

81. “Wetland boundary” means the boundary or outer edge of a wetland as delineated in accordance with the federal wetland delineation manual and applicable regional supplements (as updated), as required by WAC 173-22-035.

82. “Wetland category” means category as defined in Washington State Wetland Rating System for Western Washington – 2014 Update (Ecology Publication No. 14-06-029, October 2014), or as revised and adopted by the department.

83. “Wetlands specialist” means a person with experience and training in wetland issues who is able to submit substantially correct reports on wetland delineations, classifications, functional assessments and mitigation plans. “Substantially correct” means that errors, if any, are minor and do not delay or affect the site plan review process. Qualifications of a wetlands specialist include:

a. Either:

i. Certification as a professional wetland scientist (PWS) or wetland professional in training (WPIT) through the Society of Wetland Scientists; or

ii. Bachelor of Science degree in the biological sciences from an accredited institution and five years of professional field experience; and

b. The prior successful completion of at least three wetland reports.

84. “Wildlife biologist” means a person with experience and training in the principles of wildlife management and with practical knowledge in the habits, distribution and environmental management of wildlife. Qualifications include:

a. Either:

i. Certification as a professional wildlife biologist through the Wildlife Society; or

ii. Bachelor of Science or Bachelor of Arts degree in wildlife management, wildlife biology, ecology, zoology, or a related field from an accredited institution and five years of professional field experience; and

b. The prior successful completion of at least three habitat management plans.

85. “Wildlife habitat” means 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 include areas of relative density or species richness, breeding habitat, winter range, and movement corridors. These also include habitats of limited availability or high vulnerability to alteration, such as cliffs, streams and wetlands.

86. “Zone of influence” means an area, usually upslope from a geologically hazardous area, where changes in land use and hydrology can affect the stability of the geologically hazardous area. The “zone of influence” is defined as 300 feet upslope from slopes greater than 40 percent, and 200 feet upslope from slopes greater than 15 percent but less than 40 percent that are determined to be geologically hazardous areas. (Ord. 2024-04 § 5, 2024; Ord. 2018-01 § 2 (Exh. A), 2018)