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ORD 91-07 ENVIRONMENTALLY SENSITIVE AREASPassed: February 7, 1991 Effective date: February 19, 1991 CHAPTER 18.84 ENVIRONMENTALLY SENSITIVE AREAS Sections: 0g,01/VAA)d-9, ASO, 9/- C7 GENERAL PROVISIONS 18.84.010 Statement of Policy 18.84.020 Purpose 18.84.030 Environmentally Sensitive Areas - Scope 18.84.040 Definitions ,E D C-,„ 1-1 t FE 9 2 0 1091 CITY 01C �t&.ISLOW ENVIRONMENTAL MANAGEMENT OF DRAINAGE BASINS 18.84.050 Definition of Environmental Management of Drainage Basins 18.84.055 Sportsman's Club Stream Drainage Basin (A) 18.84.060 Rotary Park Drainage Basin (B) 18.84.065 Downtown Drainage Basin (C) 18.84.070 The Ravine Drainage Basin (D) 18.84.075 Twin Ravines Drainage Basin (E) 18.84.080 Wing Point/Yeomalt Drainage Basin (F) REVIEW 18.84.090 Standards 18.84.095 Permit Procedure 18.84.100 Administrative Use Review SPECIAL PROVISIONS BY ENVIRONMENTALLY SENSITIVE AREAS TYPE ARCHAEOLOGICAL SITES 18.84.110 Archaeological Site Description SENSITIVE SOIL CONDITIONS 18.84.120 Geological Hazardous Areas - Reports 18.84.125 Geological Hazardous Areas - Excessive Slope 18.84.130 Geological Hazardous Areas - Grading Plan 18.84.135 Geological Hazardous Areas - Erosion Control Plan 18.84.140 Geological Hazardous Areas - Stormwater Control System Plan SIGNIFICANT HABITAT AREAS 18.84.150 Environmentally Sensitive Areas Descriptions 18.84.155 Streams and Stream Buffers - Uses 18.84.160 Streams and Stream Buffers.- Applicable Standards 18.84.165 Streams and Stream Buffers - Erosion Control Plan 18.84.170 Streams and Stream Buffers - Stormwater Control Plan 18.84.175 Streams and Stream Buffers - Agencies to Consult 18.84.180 Streams and Stream Buffers - Best Management Practices ENVIRONMENTALLY SENSITIVE AREAS Page 1 February 7, 1991 WETLANDS 18.84.190 18.84.195 18.84.200 18.84.205 18.84.210 18.84.215 18.84.220 18.84.225 Wetlands - Functions Wetlands - Categorization Wetlands - Wetland Buffers - Uses and Regulated Activities Wetlands - Buffer Zone Functions Wetlands - Minimum Buffer Standards Wetlands - Standards Applicable Wetlands - Mitigation Required Density/Intensity Calculations OFFICIAL MAP 18.84.230 Official Maps. Streams, Wetlands and Significant Wildlife Habitats Geologically Hazardous Areas and Archaeological Sites 18.84.010 Statement of Policy. It is the policy of the City of Winslow that qualities of the natural and developed environment that make Winslow special be protected and enhanced; that health, life, and property be protected from environmental hazard, both natural and man-made; and that the downtown area be made a more pleasing experience for those who visit by improving the City's unity, liveability, atmosphere, and attractiveness. (Winslow Comprehensive Plan Ordinance No. 87-29, Part II -E, 1987.) The term "Environmentally Sensitive Areas" is substituted for the term "Areas of Special Significance" in all city ordinances and other documents approved prior to the effective date of the ordinance codified in this chapter. 18.84.020 Purpose. Because of special physical or cultural conditions in the goal stated above, and as defined in Winslow Comprehensive Plan Part III Section A, it is the intent of this chapter to accomplish the following: A. To mitigate unavoidable impacts to Environmentally Sensitive Areas by regulating alterations. B. To protect the public from personal injury, loss of life or property damage due to erosion or steep slope failures. C. To prevent adverse environmental impacts to water quality, wetlands and streams. D. To protect unique, fragile and valuable elements of the environment including wildlife and its habitat. E. To protect the public against losses which occur when Environmentally Sensitive Areas are misused, such as: 1. publicly funded mitigation of avoidable impacts; �. cost for public emergency rescue and relief operations where the causes are avoidable; ENVIRONMENTALLY SENSITIVE AREAS W Page 2 February 7, 1991 3. degradation of the natural environment; and A. toss of potential viewpoints in new development, both public and private. F. To alert appraisers, assessors, owners, potential buyers and lessees to the natural limitations of these sensitive areas. G. To provide responsible officials with sufficient information to adequately protect sensitive areas when approving, conditioning or denying public or private development proposals. H. To implement the policies of the State Environmental Policy Act (SEPA) of 1971. I. To implement the policies of the Shoreline Management Act of 1971. 18.84.030 Environmentally Sensitive Areas - Scope. This chapter shall apply to "Environmentally Sensitive Areas," meaning those lands within the City of Winslow which are subject to natural hazards; contain significant renewable resources; support unique, fragile or valuable elements of the natural environment; or contain valuable cultural resources. NO ACTION SHALL BE UNDERTAKEN BY ANY PERSON WHICH RESULTS IN ANY ALTERATION OF AN ENVIRONMENTALLY SENSITIVE AREA EXCEPT IN COMPLIANCE WITH THE REQUIREMENTS AND GOALS, PURPOSES AND OBJECTIVES OF THIS CHAPTER. 18.84.040 Definitions. 1. "Anadromous Fish", species which migrate from the sea to spawn in fresh water, their offspring return to the sea and spend most of their adult lives there. 2. "Archaeological Sites", meaning those locations of prehistorical or historic interest including, but not limited to, burial sites, camp sites, rock shelters, caves and the artifacts, implements and remains of the culture. 3. "BMP", Best Management Practice. 4. "Environmentally Sensitive Areas", meaning any of those areas of Winslow which are subject to natural hazards or those landform features which in their natural state carry, hold or purify water and support unique, fragile, or valuable natural resources including fishes, wildlife and other organisms and their habitat. Environmentally Sensitive Areas include, but are not limited to, the following landform features: archaeological sites, erosion hazard areas, geologically hazardous area, wetlands, streams, and the protective buffers necessary to protect each of the above landform features as defined in this chapter, and the public health, safety and welfare. 5. "Erosion Hazard Area", means a landform subject to being worn away by the action of water, wind, freeze -thaw or ice. Page 3 ENVIRONMENTALLY SENSITIVE AREAS February 7, 1991 6. "Geologically Hazardous Areas" means areas that because of their susceptibility to erosion, sliding, earthquake, or other geological events, are not suited to the siting of commercial, residential, or industrial development consistent with public health or safety concerns. This group of soils includes Cathcart silt loam 15 to 30% slopes, Dystric Xerorthents 45 to 70% slopes, and Kitsap silt loam 8 to 45% slopes, and slopes subject to a severe risk of landslide including active and currently inactive slides, and which contain: a. Slopes with unstable soils greater than fifteen percent (15%) or eight and one-half degrees (8 1/2 ) and b. Impermeable subsurface material (typically silt and clay), sometimes interbedded with permeable subsurface material (predominantly wet sand and gravel) between the top and base (foot) elevations, and C. Springs or seeping ground water during the wet season (November to February): or d. Slopes greater than forty percent or twenty one and eight tenths degrees. 7. "Protective Buffers", meaning an area which provides the margin of safety, as shown in Figures A to D through protection of slope stability, attenuation of surface water flows and landslide hazards reasonably necessary to minimize risk to the public from loss of life or well-being or property damage resulting from natural disasters; or an area which is an integral part of a stream or wetland ecosystem and which provides shading, input of organic debris and coarse sediments, room for variation in stream or wetland edge, habitat for wildlife and protection from harmful intrusion necessary to protect the public from losses suffered when the functions and values of aquatic resources are - degraded. Page 4 ENVIRONMENTALLY SENSITIVE AREAS February 7, 1991 r,I I I — —/. Il�e= A -3,i CYN 4f F I w U C vi w �,/�s•IrY .} r';ttr /� r 7 I NN cti t r�'t N N + ._ En O W I H: /• , . •p � � ass <: ' , rx ' W. i � •� . , ' (;" � f t`; fat 4—) F-1 ,,� 7•,1 �11• :, }i',1. � �: ,`. •1. •I to 111 (•�'.' IL1?�,�s� i~ z 1 .7 ',�:(I7•f�}�� ■ '.a .. - �- +�t'i W � � . 1.''i :1� r`��7 ' • ' �' ..-* '• . ' 1 'b • ' O-„' O CA aa /•� 11 ' . • il��.. ... .. - r-4. ' ' ' V1.' (L1 1' k �' >~ • Rte+ PI 14. � o •� t' �',•,•: •,,� �....- � .Its..::.:--•--. 00 VI V00, - ; H Al O�- (9 /I A C) Q 0' in C) in W O V) c UJ J 0 D CD w .$a cv C, W 4-* q) Lo cl cd CL 4-4 CJ bo H Al O�- (9 /I A C) Q 0' in C) in V) c H Al O�- (9 /I A C) Q 0' in C) in 8. "Qualified Professional", meaning registered engineers working in their field of expertise. Also, professionals in other environmentally oriented disciplines who are certified by National or International organizations. 9. ",Riparian Zone", meaning that area which is transitional between wetlands or streams and upland terrestrial habitats. 10. "Significant Wildlife Habitat Areas", meaning those areas which are visited by native animal species with unusual frequency, density or diversity; or by those plant and animal species identified as either endangered threatened, sensitive, or monitored by the Washington State Department of Wildlife or by the Washington Department of Natural Resources, Natural Heritage Program, and used for critical processes such as feeding, breeding, nesting, resting, and migration. 11. "Specific Areas" identified as being environmentally sensitive in the Winslow Comprehensive Plan. 12. "Streams", meaning those surface waters, contained within a defined channel or bed, which flow into or become connected with other surface waters generally at least once per year. This includes DNR Stream Types 1-5 (WAC 222-16-020, or as amended hereafter). This definition excludes roadside ditches or storm water runoff devices. 13. "Wetlands",as defined by State Law, meaning those areas that are inundated or saturated by ground or surface water at a frequency and duration sufficient to support, and that under normal circumstances do support, a prevalence of vegetation typically adapted for life in saturated soil conditions. Wetlands generally include swamps, marshes, bogs, and similar areas, such as sloughs, potholes, wet meadows, river overflow channels, and open water ponds less than twenty acres in size. Where the vegetation has been removed or substantially altered, a wetland shall be determined by the presence or evidence of hydric or organic soils. 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, detention facilities, wastewater treatment facilities, farm ponds, and landscape amenities. However, wetlands may include those artificial wetlands intentionally created from nonwetland areas created to mitigate conversion of wetlands, if permitted by the city. 1.4. "Wetland edge", meaning the line defining the outer edge of a wetland established by using the Federal Manual for Identifying and Delineating Jurisdictional Wetlands dated January 10, 1989, and jointly published by the U.S. Fish and Wildlife Service, the U.S. Army Corps of Engineers and the U.S. Soil Conservation Service. Page 7 ENVIRONMENTALLY SENSITIVE AREAS February 7, 1991 ENVIRONMENTAL MANAGEMENT OF DRAINAGE BASINS 18.84.050 Definition of Environmental Management of Drainage Basins The City has identified special environmental management/drainage basins in order to provide specifically designed management techniques for each basin. 18.84.055 Sportsman Club Stream Drainage Basin (A). The boundary of the Sportsman Club Stream Drainage Basin is roughly south of New Brooklyn Road, east of Finch Road and Sportsman Club Road, and west of Weaver Road. Sensitive areas identified within this management area are: A. Stream and Associated Wetlands. B. Geologically Hazardous Areas: Excessive Slopes. C. Significant Wildlife Habitat. D. Probable Archaeological Site (Midden). This drainage basin begins in a mixed alder -willow wetland north of New Brooklyn Road with heavily wooded uplands on both sides and a stream channel which moves south. Within the area between New Brooklyn Road and High School Road the stream flows into and out of the Sportsman Club Pond.Above and below the pond the stream flows through a narrow corridor which expands into broad alder -willow associated wetlands near High School Road.Within this area both side slopes of the drainage area are heavily wooded with conifers being the dominant vegetation. Farther south, between -High School Road and Wyatt Avenue, the stream corridor tapers down and flows through an area characterized by willow thickets. Side slopes of this basin include a mix of fields, pastures and woodlands. Entering the Winslow city limits at Wyatt Avenue the stream enters an increasingly steep ravine corridor. The ravine becomes less severe as the stream bends to the southwest and gains entrance to the tidal mudflats of Yagle Harbor. The side slopes of this basin area are characterized by heavily wooded slopes of conifer big leaf maple, and alder. Some small areas of stream -associated wetlands can be found in this section especially in the southern portion. The entire stretch of the stream basin, from headwaters to mouth, is significant wildlife habitat due to use of the stream corridor for food, protection, nesting, rearing, and migration by a variety of wildlife species. Geological Hazard Areas are located mainly within the ravine area south of Wyatt Avenue. Page 8 ENVIRONMENTALLY SENSITIVE AREAS February 7, 1991 18.84.060 Rotary Park Drainage Basin (B). The boundary of the Rotary Park Drainage Basin is roughly south of High School .Road, east of Weaver Road, and west of Grow Avenue. Sensitive areas identified within this management area are: A. Stream and Associated Wetlands. B. Archaeological Site. C. Significant Wildlife Habitat. This Drainage Basin begins in a small wetland west of Weaver Road and another small wetland east of Rotary Park. The riparian corridor, which seasonally drains the basin, is located in the western portion of the basin, and runs in a southerly direction to Wyatt Avenue. Within this area the stream channel is undefined in the north portion where the predominant vegetation is shrubs and grasses. In the southern portion the stream channel becomes more defined and flows through a riparian corridor of alder and thick blackberry brambles before reaching Wyatt Avenue. Outside of the riparian corridor can be found a mixture of scotch broom thickets, openly grassed areas, and small areas of woodland. Housing densities are heavier in the northeast portion of the basin. South of Wyatt Avenue the seasonal stream flows though a ditch in the front yards of homes on the east side of Weaver Road until it reaches the pumping station where it is culverted beneath a gravel access road running east and west. Behind or to the east of the same houses on Weaver Road is located a relatively broad corridor of woodland which runs north -south. This corridor qualifies as Significant Wildlife Habitat because it provides a migration route which is lacking in the ditched area -along Weaver Road. From the outfall of the culvert beneath the gravel road, the stream enters a narrow ravine within an area of large old conifer trees. The stream then enters Eagle Harbor east of the old historic cannery. The small grove of large conifer trees is a significant area because of the unique quality of trees this age and size. A major Archaeological Site (midden) is located within this basin to the west of the old historic cannery. 18.84.065 Downtown Drainage Basin (C). The boundary of the Downtown Drainage Basin is roughly south of High School Road, east of Grow Avenue, and west of Ericksen Avenue. Sensitive areas within this management area are: A. Archaeological Site (Midden). B. Riparian Zone. This basin is located in the most urbanized section of Winslow.- All but one small section of the stream, which drains the area, has been tight- lined in various fashions and runs beneath the city. There is a small riparian area east of Madison Avenue where the stream outfalls from the culvert and enters a small inlet of Eagle Harbor. The vegetation in this area consists of shrubs which are used mainly by avian species. Page 9 ENVIRONMENTALLY SENSITIVE AREAS February 7, 1991 Two small Archaeological Sites (middens) are located within the Winslow Waterfront Park near the shoreline. 18.84.070 The Ravine Drainage Basin (D). The boundary of The Ravine Drainage Basin runs roughly south of New Brooklyn Road, east of Commodore Lane, Madison Avenue an Ericksen Avenue and west of Ferncliff Avenue. Sensitive areas within this management area are: A. Stream and Associated Wetlands. B. Significant Wildlife Habitat. C. Geologically Hazardous Areas: Excessive Slopes. This largest of the drainage basins begins in a small wetland outside of the city limits on the north side of New Brooklyn Road. The direction of stream flow from this point is to the Southeast under New Brooklyn Road and through an altered area where a portion of the stream is culverted until it passes under Madison Avenue. At this point the stream enters the city limits and flows through an area of alder and willow wetlands. The stream then bends to a more southerly direction and flows toward Sakai Pond. From the Northeast, a small tributary flows beneath SR 305 and enters the main stream. Upon entering Sakai Pond and associated wetlands. the riparian corridor widens significantly. From Sakai Pond to High School Road the stream flows through a small wetland and is then culverted beneath High School Road. Within the area described above there are unstable soils to the west of the stream and wetlands. Between High School Road and the culvert under SR 305 the stream is highly manipulated with no resemblance of the natural drainage. The stream, upon exiting the culvert to the east of SR 305, enters The Ravine which is characterized by steep slopes on both sides and good examples of native vegetation. Overall, this area can be considered pristine. The Ravine runs in a wide gradual arc to the East, then South, then West, where it is then culverted again beneath SR 305. The Ravine then turns to the South and continues to Eagle Harbor after being culverted under Winslow Way. The Ravine Drainage Basin has very Significant Wildlife Habitat values. This is mainly due to habitat diversity, ample migration corridor width, variations in slope and stream gradient, and relatively stable vegetative composition. 18.84.075 Twin Ravines Drainage Basin (E). The boundary of the Twin Ravines Drainage Basin is roughly south Byron Drive, east of Ferncliff Avenue, and west of Cherry Avenue. Sensitive areas within this management unit are: A. Stream and Associated Wetland. B. Significant Wildlife Habitat. C. Geologically Hazardous Areas: Excessive Slopes. Page 10 ENVIRONMENTALLY SENSITIVE AREAS February 7, 1991 There are two main drainage within the Twin Ravines Drainage Basin. The west drainage starts just west of Ferncliff Avenue and flows under the road toward the east. The stream then runs in a meandering Southeasterly direction where it bisects three small wetlands located in an -area of predominantly alder -big leaf maple/salmonberry vegetation. This area is fairly pristine and is buffered well by an expanse of surrounding woodland. As the stream reaches Wing Point Way a significant ravine has developed. The east drainage begins north of Byron in a mixed alder/willow wetland. After being culverted under Byron Drive the stream flows to the south roughly paralleling the west drainage. The vegetation and landforms are similar to that described for the West drainage. The East drainage stream also emerges from the wooded expanse in a ravine which began to the north of the end of Azalea Street. This stream as well as the West stream flow under Wing Point Way before joining at a very significant wetland on the North shore of Eagle Harbor. The Twin Ravine Drainage -Basin has very Significant Wildlife Habitat values. This is mainly due to habitat diversity, ample migration corridor width, variations in slope and stream gradient, and relatively stable vegetative composition. It is especially recognized as currently having the best migration corridor in Winslow for the movement of wildlife from the marine environment to the upland environment and vice -versa. This is due to relative few sections of disturbance or alterations within the drainage. The Twin Ravines contain Geological Hazard Areas with both steep slopes and unstable soils. The ravines become more severe as they near Wing Point Way and their eventual joining areas become more marked as the streams near their union. Wetlands which are found within the Twin Ravines Drainage Area include those - associated with the twin streams as well as a small wetland with some open water which is located between Ferncliff Avenue and the West stream of the Twin Ravines. The very significant wetland at the mouth of the Twin Ravines is located mostly outside of the city limits but should be recognized as one of the most important of all the wetlands mentioned within the Drainage Basins. 18.84.080 Wing Point/Yeomalt Drainage Basin (F). The boundary of the Wing Point/Yeomalt Drainage Basin is roughly all lands within the Winslow City limits east of Cherry Avenue. Sensitive areas within this management unit are: -A. Significant Wildlife Habitat. B. Riparian Gone. The Wing Point / Yeomalt Drainage Basin has no defined perennial streams. However there are two intermittent drainage. One of these generally flows ----- between Cherry Avenue and Park Avenue in a Southerly direction and, after flowing under Wing Point Way, it becomes a grass swale through the golf course. The other drainage flows in generally a Northeasterly direction from the west side of the intersection of Grand, Yeomalt, and Park Avenues toward ENVIRONMENTALLY SENSITIVE AREAS 'Page 11 February 7, 1991 the eastern shoreline of Bainbridge Island. Both of these drainage originate in a small alder/willow bottom to the west of the same intersection. Both of these drainage, through principally their riparian zones, contain some significance for wildlife. REVIEW 18.84.090 Restrictions. The regulations and standards of Winslow Title 18 pertaining to the several use classifications shall be subject to the protective measures required by this chapter. No development, use or activity may occur in any Environmentally Sensitive Areas or protected buffers except as specifically allowed by this chapter. 18.84.095 Permit Procedure. Prior to development of any property that contains, or is adjacent to an Environmentally Sensitive Area, the property owner shall submit plans and obtain approval of the proposed development as follows: A. The applicant shall: 1. Conduct a survey of the project site to determine if the project will impact the environmentally sensitive areas as defined in sections 18.84.050 to .080. 2. Affirm that no material alteration has occurred on the site in violation of any Federal, State or Local law. If such alteration has occurred, the applicant must submit a summary of mitigation efforts completed as of the date of the application and a plan for future mitigation. The application shall not be considered complete until such time as the City approves such mitigation efforts or plans in accordance with mitigation standards outlined in SEPA rules at WAC197-11-768. 3. Demonstrate that any development proposal submitted conforms to the purposes,. standards, and protection mechanisms of this chapter. 4. Submit a special sensitive areas study prepared in accordance with industry standards by a qualified professional as defined in section .040: a) to identify and characterize any Environmentally Sensitive Areas as a part of the larger development proposal site; and b) to assess impacts on such Environmentally Sensitive Areas both from activities outside the Environmentally Sensitive Areas and from any proposed alteration of the Environmentally Sensitive Areas determined to be permitted under the chapter; and c) based upon the assessment in 4a and 4b above, propose adequate protection mechanisms for the specific Environmentally Sensitive Areas which may include but not limited to mitigation, monitoring, and bonding measures. ENVIRONMENTALLY SENSITIVE AREAS Page 12 February 7, 1991 5. Prepare other such plans and documentation as required in this document. B. The City shall: 1. Determine from its own records whether the development proposal site has been previously illegally altered or if the applicant previously has been found in violation of this ordinance; 2. Confirm the nature and type of the Environmentally Sensitive Area and evaluate the special Environmentally Sensitive Area study; 3. Determine whether the development proposal is consistent with this chapter; 4, Determine whether proposed alterations to Environmentally Sensitive Areas are appropriate in accordance with the standards contained in this ordinance or are necessary to allow reasonable use of the property; 5. The planning agency shall review the materials submitted by the applicant and prepare recommendations to grant, deny or condition a permit for the proposed development. It shall then forward both its own recommendations and the data submitted by the applicant to the hearing examiner for further action in accordance with the hearings procedure ordinance, codified at chapter 2.16. C. No application shall be considered complete until the Environmentally Sensitive Areas study required by this chapter is submitted to the City of Winslow as part of the development proposal application. 18.84.100 Standards. The standards to be applied under Sections of this chapter are outlined in the SEPA Rules, WAC 197-11-768 "Mitigation". Mitigation includes the following, with monitoring the impact and taking appropriate corrective measures being a part of any mitigation: A. Avoiding the impact altogether by not taking a certain action or parts of an action. B. Minimizing impacts by limiting the degree or magnitude of the action and its implementation, by using appropriate technology, or by taking affirmative steps to avoid or reduce impacts. C. Rectifying the impact by repairing, rehabilitating, or restoring the affected environment. D. Reducing or eliminating the impact over time by preservation and maintenance operations during the life of the action. E. Compensating for the impact by replacing, enhancing or providing substitute resources or environments. Page 13 ENVIRONMENTALLY SENSITIVE AREAS February 7, 1991 SPECIAL PROVISIONS BY ENVIRONMENTALLY SENSITIVE AREAS TYPES 18.84.110 Archaeological Site Description. In order to preserve native Indian burial grounds and historic archaeological sites acknowledged to be a finite, irreplaceable and nonrenewable cultural heritage of the yeople of Winslow, the developer shall submit a plan delineating the archaeological site and identify how development will have no impact on the site. Developments may be required to meet the following conditions: A. Whenever in the course of excavation or development, artifacts and items of possible archaeological interest are discovered, the excavation or development must immediately be stopped, and the find must be reported to the City of Winslow. The City shall then notify the Office of Archaeology and Historic Preservation for their review and comment. B. The City of Winslow may add mitigating conditions to the project approval in order to protect these sites or artifacts, so long as normal permit procedures are followed. C. Inhere known sites, recorded by the Office of Archaeology and Historic Preservation, are proposed for development, the City of Winslow shall consult this agency for its recommendations, and may deny the permit where the archaeological value of the site outweighs the development value. SENSITIVE SOIL CONDITIONS 18.84.120 Geologically Hazardous Areas -- Report. Every application for development within a Soil Instability Area shall contain an engineering geology or soil engineering report prepared by a qualified professional. The report shall include a description of the geology of the site, conclusions and recommendations regarding the effect of geologic conditions on the proposed development, and opinions and recommendations of the adequacy of the site to be developed. 18.84.125 Geologically Hazardous Areas -- Excessive Slope. Those areas with slopes in excess of forty percent (40%) or twenty-one and eight -tenths degrees (21.8 degrees) shall be considered as unbuildable. 18.84.130 Geologically Hazardous Areas -- Grading Plan. (See also Chapter 15.28). A detailed clearing and grading plan is required, specifically identifying vegetation to be removed, schedule for vegetation removal and replanting, and the method for vegetation removal. Clearing and grading activities within a Soil Instability Area shall be undertaken only during the drier months of the year. Undergrowth shall be retained to the extent feasible, and yarding methods which minimize soil disturbance shall be used. Page 14 ENVIRONMENTALLY SENSITIVE AREAS February 7, 1991 L8.84.135. Geologically Hazardous Areas -- Erosion Control Plan. A temporary erosion control plan shall be provided, identifying specific mitigating measures to be implemented during construction which will protect the slope from erosion, siltation, landslides and deleterious construction materials. 18.84.140 Geologically Hazardous Areas--- Stormwater Control System Plan. A detailed stormwater control system plan shall be required in accordance with Chapter 15.24 of the Winslow Municipal Code, Land Clearing and Grading. The system shall consider existing and proposed project developments, including areas adjacent to but outside city limits. The plan shall provide for on-site detention/retention of stormwater, and may incorporate, at the discretion of the City of Winslow, permanent pollution control structures such as oil -water separators, and biofiltration structures such as grass -lined swales and wet ponds. A maintenance program for the entire storm drainage system that assigns responsibilities and identifies maintenance activities and schedules shall be a component of the stormwater control plan. SIGNIFICANT HABITAT AREAS 18.84.150 Significant Habitat Areas. In order to preserve the wildlife heritage that exists in Winslow, if a development proposal contains significant wildlife habitat or -habitat for special plants, the developer shall submit a plan identifying how development impacts will be mitigated, including (but not limited to) establishment of buffer zones, preservation of critically important plants and trees, limitation of access to habitat area, and construction timing. This plan shall be prepared by a qualified professional. 18.84.155 Streams and Stream Buffers -- Uses. To maintain the natural functions and aesthetic quality of streams and their associated buffers to control siltation, minimize turbidity, maintain streamflows, protect nutrient reserves, maintain proper water temperatures, protect fish usage, preserve natural flood storage capacity, provide ground water recharge and release, and protect wildlife habitat associated with these areas, uses shall be limited to low impact human uses which do not negatively affect those natural functions. A. Streams -- Permitted uses shall be as follows: 1. Education and scientific research; 2. Passive recreation, including fishing, hiking, camping, and access to the water's edge, without the use of fill of any kind; 3. Maintenance and repair of overhead utilities; 4. Maintenance and repair of underground gas, oil, water, sanitary sewer or storm sewer lines; 5. Maintenance, repair and operation of service -ability structures or fills in existence on the effective date of this ordinance; 6. Maintenance and repair or improvements to existing service roads or streets in existence on the effective date of this ordinance which include no right-of-way expansion. ENVIRONMENTALLY SENSITIVE AREAS r Page 15 February 7, 1991 B. Streams -- Conditional uses are as follows: 1. Construction of new road crossings; 2. Construction of new overhead or underground utility lines. C. Stream Buffers -- Permitted uses shall be as follows: Those uses listed under subsection A of this section, and the following: I. The continuance of farming, where it does not include grazing animals or the application of pesticides, excluding fungicides, or silviculture where these activities are in existence on the effective date of this ordinance. D. Stream buffers -- Conditional use review Those uses listed under subsection B of this section, and the following: 1. A "conversion" as defined by the Forest Practices Act (RCW76.09) from forestry production to another use; 2. The selective harvesting of merchantable timber not to exceed thirty percent in any ten-year period and to include reforestation; 3. Enhancement of the existing vegetation with species suitable for the soil and hydrological conditions. 18.84.160 Streams and Stream Buffers -- Applicable Standards. To retain the natural functions of streams and stream corridors the following measures and natural buffers spall be maintained: A. Streamside vegetation shall be maintained as determined by the following provisions: 1. 'For ravines with banks greater than ten (10) feet in depth, maintain the existing vegetation within the ravine and a strip twenty-five (25) feet from the top of the bank; 2. Where there is no ravine or the bank is less than ten (10) feet in depth, maintain existing vegetation on both sides of the stream as measured from the ordinary high water mark based upon the following classification of stream types: a. perennial or year-round flowing streams, minimum fifty (50) feet from normal high water on each side of stream. b. seasonal or intermittent streams, minimum twenty-five (25) feet from normal high water on each side of stream. C. Where there is conflict between stream and wetland buffer, the more restrictive shall apply. B. The City may reduce this distance when a lot of record on the date of adoption of this ordinance is less than one hundred (100) feet in depth, a proportionate reduction of up to fifty (50) percent of the standard may be allowed based upon the size of the lot. C. The City may increase this distance through analysis of available data and/or the presence of special features. The increase shall be limited to a doubling of the buffer size and can apply to all or part of the Page 16 ENVIRONMENTALLY SENSITIVE AREAS February 7, 1991 r buffer area. The presence of any of the following special features shall warrant such an evaluation: 1. Flows into a wetland which has special features; or 2. Supports an unusuallv high population of anadromous fish; or 3. Supports special animal, plant or plant community or a monitored animal species; or 4. Supports an abundance or diversity of animal species unusual for Winslow; or 5. Contains a special geologic feature such as a waterfall. 18.84.165 Streams and Stream Buffers -- Erosion control plan. To protect the natural functions and aesthetic qualities of a stream and stream buffer, a detailed temporary erosion control plan which identifies the specific mitigating measures to be implemented during construction to protect the water from erosion, siltation, landslides and hazardous construction materials shall be required. The City of Winslow shall review the plan with the appropriate state, federal and tribal agencies and any adjacent jurisdiction. 18.84.170 Streams and Stream Buffers -- Stormwater control plan. A detailed stormwater control system plan shall be required except for single-family building permits. The design of the system shall take into consideration existing and proposed project developments, including areas adjacent to but outside the city limits, so that accumulative effects will be addressed and the management of the city's stormwaters will be as broad and comprehensive as possible. The plan shall provide for'on-site detention/retention of stormwater, and may incorporate, at the discretion of the City of Winslow, permanent pollution control structures such as oil- water separators and biofiltration structures such as grass -lined swales and wet ponds. A maintenance program for the entire'storm drainage system, which assigns responsibilities and identifies maintenance activities and schedules, shall be a component of the stormwater control plan. [8.84.175 Streams and Stream Corridors -- Agencies to consult. To assure the unobstructed passage of fish and to protect all other functions in the life cycles of fish, alteration of stream course and all instream work should be avoided. Where such alteration or instream work is unavoidable, it must be planned in conjunction with the appropriate state, federal and tribal agencies and any adjacent jurisdiction. Further, it must obtain a hydraulic project approval from the Washington State Department of Fisheries. 18.84.180 Streams and Stream Corridors -- Best Management Practices. To protect water quality, the use of herbicides or pesticides, excluding fungicides, within one hundred feet of such waters is prohibited, and the use of fertilizer within one hundred feet of such waters is discouraged and may be restricted or prohibited so as to prevent the polluting of such waters. The City of Winslow may require restrictions on the above activities be made part of protective covenants of the development. Page 17 ENVIRONMENTALLY SENSITIVE AREAS February 7, 1991 WETLANDS 18.84.190 Wetlands -- Functions. Wetland functions are natural processes performed by wetlands and include functions which are important in maintaining the availability and quality of water such as purifying water, acting as recharge and discharge areas for - groundwater aquifers and moderating surface water and storm water drainage patterns as well as performing other functions such as facilitating food chain production, providing habitat for nesting, rearing and resting sites for aquatic, terrestrial or avian species and such other functions including but not limited to those set out in U.S. Army Corps of Engineers regulations at 33 C.F.R. Section 320.4(b)(2)(1988). 18.84.195 Wetlands -- Categorization. Wetland categorization means the placement of all wetfands in Winslow in one of the following categories as described in the U.S. Fish and Wildlife Service Classification of Wetlands and Deepwater Habitats of the United States FWS/OBS-79/31 (December 1979). A. Type 1 wetlands are those that meet any of the following criteria: �. The presence of species proposed or listed by the federal government or state of Washington as endangered, threatened, rare oV monitor sensitive or critical or outstanding potential habitat for those species; 2. Wetlands having at least 25% open water in dispersed patches with two or more subclasses of vegetation; 3. The presence or indication of significant archaeological or historic cultural sites as identified of federal, state, local or tribal registers. 4. Irreplaceable or rare wetland types. These wetland types include, but are not limited to the following: a. high quality examples of a native wetland listed in the Terrestrial and/or Aquatic Ecosystem elements of the WA Natural Heritage Plan. b. sphagnum bogs, fens or significant peat deposits. C. kelp and eelgrass beds. d. estuarine wetlands. e. mature forested swamp communities. B. Type 2 Wetlands are those that meet any of the following criteria: 1. Wetlands that do not contain features outlined in subsection A. 2. Wetlands having two or more wetland classes. 3. Wetlands contiguous with salmonid fish -bearing waters, including streams where flow is intermittent. 4. Wetlands with significant use by fish and wildlife. C. Type 3 Wetlands are those that do not contain features outlined in subsections A and B; have only one wetland class; and have only one dominant plant species (monotypic vegetation). Page 18 ENVIRONMENTALLY SENSITIVE AREAS February 7, 1991 Where portions of a wetland system have attributes from several rating categories, the highest category rating shall apply to the entire system. D. Type 4 Wetlands are those regulated wetlands in the Puget Sound planning area of ordinary resource value based on monotypic vegetation of similar age and class, lack of special habitat features, and isolation from other aquatic systems. 18 84 200 Wetlands and Wetland Buffers -- Uses and Regulated Activities._ To maintain the natural functions of wetlands and their buffers to control siltation, minimize turbidity, protect nutrient reserves, maintain streams flows, preserve natural flood storage capacity, protect fish bearing waters, provide ground water recharge, protect associated wildlife habitat, and reduce the impact of subsidence and earthquakes within these areas, uses shall be limited to low impact human uses which do not degrade those natural functions. A. Wetlands -- Permitted Uses are as follows: 1. Education and scientific research. 2. Passive recreation, including fishing, hiking, camping, without the use of fill of any kind. 3. Maintenance and repair of overhead utilities. 14. Maintenance and repair of underground gas, oil, water, sanitary sewer or storm sewer lines provided no maintenance road is constructed. 5. Maintenance, repair, or operation of service -ability structures or fills in existence on the effective date of this section, provided that no further encroachment occurs, and the uses attempt to comply with the intent of this -chapter. 6. Maintenance and repair or improvements to existing service roads or streets in existence on the effective date of this ordinance which, includes no right-of-way expansion and minimize any adverse effect upon the wetland. 7. The continuation of farming, where it does not include grazing animals, or silviculture in existence on the effective date of this section. B. Wetlands -- Regulated Activities. Regulated activities or alterations shall include the following activities occurring in a wetland or its buffer zone: 1. Removing, excavating, disturbing or dredging soil, sand, gravel, minerals, organic matter or materials of any kind; 2. Dumping, discharging or filling with any material; 3. Driving piling, or placing obstructions; 4. Destroying or altering vegetation through clearing, harvesting, shading or planting vegetation that would alter the character of a wetland; 5. Conducting an activity that results in a significant change of water temperature, a significant change of physical or chemical characteristics of wetland water sources, including quantity, or introducing pollutants. Page 19 ENVIRONMENTALLY SENSITIVE AREAS February 7, 1991 18.84.205 Wetlands -- Buffer Zone Functions. While activities undertaken within a wetland can destroy or degrade its functions, wetlands are also sensitive to environmental changes originating outside the wetland perimeter. Such changes can indirectly result in alterations to wetland hydrology, vegetation, or soils leading to dramatic changes in wetland functions. Protecting an undisturbed vegetated buffer zone next to a wetland can significantly reduce the impacts of nearby activities. The functions performed by the buffer zone generally include maintenance of wetland hydrology, water quality and providing and protecting fish and wildlife habitat. A wetland buffer zone of adequate width should be maintained between a wetland and proposed development activities to provide the following functions: A. Stabilize soil and prevent erosion. B. Filter suspended solids, nutrients, and harmful or toxic substances. C. Moderate impacts of stormwater runoff. D. Support and protect plant and animal species and biotic communities within the wetland system, including adjacent uplands. E. Protect wetland wildlife habitat from adverse impacts. F. Maintain and enhance habitat diversity and/or integrity. G: Discourage adverse human impact in wetlands. Wetland buffer zones should be retained in their natural condition unless revegetation is necessary to restore the functional value of the buffer zone. Wetland buffer zones should be reserved as common open space and designated as "native growth protection areas" where multiple ownership is involved and cooperative management is possible. 18.84.210 Wetlands -- Minimum Buffer Standards. Wetland buffer zones of natural vegetation shall be required for all development proposals adjacent to wetlands. The standard width of the wetland buffer zone shall be determined according to wetland category. Buffer width shall be measured from the delineated edge of the wetland. Standard buffer zone widths are as follows: TYPE 1 200' TYPE 2 100' TYPE 3 50' TYPE 4 25' Standard buffer zone widths shall be reduced by the City where it can be demonstrated that: Page 20 ENVIRONMENTALLY SENSITIVE AREAS February 7, 1991 1 ,. A. A reduction is necessary to avoid a substantial hardship to the applicant caused by circumstances peculiar to the property. B. The project includes a buffer enhancement plan using native vegetation which substantiates to the City that an enhanced buffer will improve the functional values of the buffer. The reduction shall not result in greater than a 507. reduction in the buffer width. C. Buffer width averaging shall be allowed only where the applicant demonstrates that the wetland contains variations in sensitivity; due to existing physical characteristics, and such averaging will not adversely impact the wetland functional values. Buffer averaging shall in no case result in buffer reductions greater than 50% of the standard width. D. Any wetland created, restored, or enhanced as compensation for approved wetland alterations shall have the standard buffer required for the category of the created, restored, or enhanced wetland. E. Regulated activities shall not be allowed in a buffer zone except for the following: 1. activities which have no substantial adverse impact on the functions provided by the wetland buffer zone. 2. stormwater management facilities having no other feasible alternative on-site. 18.84.215 Wetlands -- Standards Applicable. In order to protect the natural function of wetlands for flood water storage, flood water conveyance, sediment control, pollution control, surface water supply, aquifer recharge, wildlife habitat, and recreation, the following standards shall apply: A. When a proposed project requiring any development permit includes wetlands on the site, those wetlands shall not be disturbed or altered through excavation, filling, building, draining, dredging or other improvements unless the City determines, upon review of special studies completed by qualified professionals, that the proposed development would preserve or enhance the wildlife habitat, natural drainage, and/or other valuable functions of wetlands as discussed above and consistent with the purposes of the chapter. B. The required studies shall include habitat value, hydrology, erosion and deposition, and/or water quality studies. Such studies shall include specific recommendations for mitigating measures to be required as a condition of any approval for such development. The recommendations shall include, but are not limited to, construction techniques, or design, drainage, density specifications, and buffers. C. The City may waive the requirement for said report if, in their opinion. the proposed development would not cause significantly adverse biological and hydrological impacts, or when there is adequate Page 21 ENVIRONMENTALLY SENSITIVE AREAS February 7, 1991 information available on the area proposed for development to determine the impacts of the proposed development and protective mitigating measures. 18.84.220 Wetlands -- Mitigation Required. A. General: Prior to disturbance of a wetland pursuant to this chapter, the applicant must establish an area of wetland on site of at least a multiplier of 1.25, habitat and hydrologic value to the affected area. The wetland mitigation must be adjacent to the wetland boundary. B. Condition Preceding Development: The wetland mitigation area must be established for at least three (3) growing seasons and must receive final approval from the City prior to any actual wetland disturbance approved pursuant to this chapter. C. Reports Required: The applicant must provide the City with funds sufficient to retain a qualified wetlands biololgist. A report by that biologist must be submitted at least twice yearly and following the minimum three (3) growing season waiting period. D. Final Approval: The City may grant final approval to a wetland mitigation area if the final report submitted documents to its satisfaction that the area has achieved habitat, water quality and water storage conditions at least equal to those of the area to be disturbed. Final approval authorizes the applicant to proceed with development permits necessary to alter the wetland boundary. 18.84.225 Density/Intensity Calculations. A. Dwelling Units per Acre: The Maximum number of dwelling units per acre for a site which contains an Environmentally Sensitive Area designation is.equal to the density permitted on the underlying zone times the buildable area in acres plus the dwelling units per acre times the unbuildable area in acres times the Development Factor as shown in the accompanying graph: B. To the extent that application of the formula may result in lot sizes less than the minimum allowed by the underlying zone they are hereby authorized, provided that the resultant of the lot is of sufficient size for an on-site waste disposal system if no sanitary sewage system exists. i.e. MAXIMUM DWELLING UNIT POTENTIAL = (DU/ACRE)(BUILDABLE AREA) +'(DU/ACRE)(UNBUILDABLE AREA)(DEVELOPMENT FACTOR) Page 22 ENVIRONMENTALLY SENSITIVE AREAS February 7, 1991 WXC18.34-225(A) Graph 'ON-5ITE .DENSITY .'CREDI T _ - - = DEVELOPMENT FACTOR, '7 — •_ _ i 21 lz �_�c�� ► CF. Di ► is Fi —TOP) ;2 — - G 0 0 10 20 40 50 EC ,0 . SO 1t;0 • jl�i�UTT.S�=_IT_a_� ��t�� r s PERCENT --G'—':' S T Rs,_ ENVIRONMENTALLY SENSITIVE -AREAS Page 23 February -7, 1991 18.84.230 Official Maps. The maps are intended to be a tool to help property owners, developers, and other interested citizens determine the natural constraints to the development of property. The maps represent only an overview of the Environmentally Sensitive Areas, not a detailed site -by -site survey. Anyone wishing to develop or redevelop a particular piece of property containing or adjacent to Environmentally Sensitive Areas will be required to have a qualified professional further refine the boundaries of these Environmentally Sensitive Areas before proceeding with design of the project. ENVIRONMENTALLY SENSITIVE AREAS Page 24 February 7, 1991