1	THE CRITICAL AREAS ORDINANCE Department of Development and Environmental Services
2	OVERVIEW OF THE CAO PACKAGE Harry Reinert, Special Projects Manager, DDES Director’s Office
3	2004 CRITICAL AREAS ORDINANCE PACKAGE Three ordinances K.C.C. 21A - zoning code (Ordinance 15051) K.C.C. 16.82 - clearing and grading (Ordinance 15053) K.C.C. Title 9 - stormwater (Ordinance 15052) Effective date: January 1, 2005
4	MAJOR CHANGES IN K.C.C. 21A.24: CRITICAL AREAS New definitions New critical areas New alteration table New alteration exception replaces PAUE and variance New wetland and aquatic area classification systems and buffer widths Critical area designation required prior to septic system and well approval New alternative methods for approval: farm and rural stewardship plans
5	NEW CRITICAL AREAS Channel migration hazard areas (component of flood hazard area) Critical Aquifer Recharge Area - (CARA) moved from K.C.C. 20.70 Wildlife habitat network - moved from K.C.C. 21A.14 Wildlife Habitat Conservation Area Aquatic areas (streams, lakes, and marine shorelines)
6	ALTERATIONS DEFINED Any human activity that results or is likely to result in an impact upon the existing condition of a critical area Includes: grading, clearing, applying pesticides, grazing domestic animals, cutting, pruning, topping Does not include: passive recreation
7	ALTERATIONS ALLOWED Must comply with critical area development standards If in a “limited alteration” critical area, must also comply with alteration conditions May need a permit
8	ALL ALTERATIONS CRITICAL AREAS All alterations, subject to development standards, are allowed in: Critical aquifer recharge area Coal mine hazard area Erosion hazard area Flood hazard area (except severe channel migration hazard area) Landside hazard area under 40% slope Seismic hazard area Volcanic hazard area
9	LIMITED ALTERATIONS CRITICAL AREAS Only alterations on alterations table are allowed in: Severe channel migration hazard area Landslide hazard area over 40% slope Steep slope hazard area Wetlands Aquatic area Wildlife habitat conservation area Wildlife habitat network
10	ALLOWED ALTERATIONS TABLE New alterations table for those critical areas where alterations are limited Replaces complete and partial exemptions sections of SAO Supplemented with a new table in K.C.C. 16.82 for grading permits
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12	ALLOWED ALTERATIONS: SAMPLE CONDITIONS 1. Limited to farm residences in grazed or tilled wet meadows and subject to the limitations of subsection D.3. of this section. 4. Allowed if no clearing, external construction or other disturbance in a wildlife habitat conservation area occurs during breeding seasons established under section 198 of this ordinance.
13	EXAMPLES ALLOWED ALTERATIONS Permit may be required, for example building, clearing or grading Fire safety Follow Fire Marshal BMPs in wetlands, aquatic areas, and wildlife areas Not allowed in land slide hazard areas and steep slopes Allowed without restriction in other critical areas Firewood collection In wetlands, aquatic areas, steep slopes, allowed for personal use Not allowed in wildlife areas Allowed without restriction in other critical areas
14	EXAMPLES ALLOWED ALTERATIONS Expansion or replacement of existing structures Maintained SAO allowances Residence – In buffers of most critical areas, including wetlands, aquatic areas and wildlife areas, replace or expand by up to 1,000 square feet Other structures – can replace, but generally cannot expand Docks and piers Construction of new docks and piers generally limited to seasonal structures Repair and replacement generally allowed
15	EXCEPTIONS Director's modification, public agency and utility exception (PAUE) and sensitive areas variance repealed Linear and non-linear exception replace PAUE and variance Reasonable use exception is modified slightly
16	LINEAR EXCEPTIONS Infrastructure that supports development that is linear in nature and includes, public and private roadways, public trails, private driveways, railroads, utility corridors and utility facilities Allows alterations to critical areas and critical area buffers May alter a condition on the table but not a development standard Must meet approval standards including: it connects to or is a public roadway, public trail, utility corridor or utility facility owned or operated by a public utility or required to overcome limitations due to gravity
17	NON-LINEAR EXCEPTIONS Only allows alterations to buffers of wetlands, aquatic areas and wildlife habitat conservation areas; not to the critical area itself Exception for category II, III or IV wetland for a public school facility May alter a condition on the table but not a development standard
18	CHANNEL MIGRATION HAZARD AREAS A component of the flood hazard area Four areas already mapped – three additional areas in process
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20	CHANNEL MIGRATION HAZARD AREAS Aquatic area buffer extends to outer edge of severe channel migration hazard area Limits on new structures, roads, etc. within the severe CMZ
21	CRITICAL AQUIFER RECHARGE AREA (CARA) Three categories based on: Groundwater susceptibility to contamination Well-head protection area or sole source aquifer Saltwater intrusion Generally, if any part of parcel is in CARA, entire parcel is subject to regulations
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23	CRITICAL AQUIFER RECHARGE AREA (CARA) Development standards limit types of activities allowed. For example: Hazardous waste disposal facilities not allowed in any CARA Underground storage tanks with hazardous substances in category l CARAs and on Vashon Island, including exempt tanks, must meet state and federal standards In category 1 and 2 CARAs, lots less than 1 acre must use special on-site septic systems New wells on Vashon Island must test for chloride
24	WILDLIFE HABITAT CONSERVATION AREA Protect breeding sites of species covered by the Comprehensive Plan Some species protected county-wide; others protected only in rural areas 10 species with specific development standards Other species handled on a case by case basis Protects breeding habitat, not foraging habitat
25	WILDLIFE HABITAT CONSERVATION AREA Protect everywhere Bald eagle Great blue heron Marbled murrelet Spotted owl Osprey Peregrine Falcon Protect outside UGA Northern goshawk Townsend’s big-eared bat Vaux’s swift Red tailed hawk
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27	SPECIAL TIMING CONSIDERATIONS Vesting Short plats: Critical areas, Stormwater, Clearing and grading in effect at time complete application submitted CUPs - vested to regulations at time complete application submitted Variances and reasonable use exceptions – vested to regulations in effect when anchor permit is vested Septic system and wells approved prior to January 1, 2005 subject to regulations in effect at time of approval
28	QUESTIONS
29	NEW BUFFERS, WETLAND AND AQUATIC AREA CLASSIFICATIONS Steve Bottheim, Supervisor DDES Critical Areas
30	INTRODUCTION Focus on wetlands and aquatic areas Outline categories, classification and associated buffers Provide resources to aid applicants in critical area assessments
31	WETLANDS 2004 Wetland Rating System for Western Washington
32	WETLAND DEFINITION Wetlands are: Non-aquatic areas (for purposes of definition) Inundated or saturated by groundwater at a frequency and duration sufficient to support, and under normal circumstances that does support, a prevalence of vegetation typically adapted for life in saturated soil conditions. Does not include artificial features made from a non-wetland areas (except for intentionally constructed wetlands for the purpose of mitigation).
33	TYPES OF WETLANDS Estuarine Natural Heritage Wetland (DNR) Bog Mature or Old Growth Forest Others: Forest Scrub-shrub Emergent Wet meadows
34	WETLAND CLASS (HGM – Hydrogeomorphic Classification) Wetlands are grouped based on landscape position and water regime Depressional Riverine Lake fringe Slope Freshwater tidal
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41	WETLAND CATEGORIES CAO adopts the Department of Ecology’s Wetland Rating and mitigation methodology Vetted through local, state and federal agencies to “harmonize” multi-agency reviews Wetlands are classified into four categories based on specific attributes such as rarity, sensitivity, and function. Functions include water quality, hydrologic, and habitat Wetland Rating Form – point system
42	Category 1 Unique or rare wetland Ecological attributes that are impossible to replace in a human lifetime Examples: estuarine, bogs, mature and old-growth forests, wetlands that perform many functions well Total score of 70 points (out of 100)
43	Category 2 Difficult but not impossible to replace Examples include smaller estuarine, mature forests, wetlands that perform functions well Score between 51 to 69 points
44	Category 3 Wetlands with functions that perform at a moderate level Disturbed in some way, less diverse and more isolated Scores between 30 to 50
45	Category 4 Wetlands with the lowest level of functions Heavily disturbed Wetlands that we should be able to replace or improve Scores less than 30
46	WETLAND COMPLEX Important to decrease wetland isolation Urban “high condition” basins and rural areas Grouping of two or more wetlands At least one Category 1 or 2; or Three category 3 wetlands; or Four category 4 wetlands Within 500-feet of each other Connected by a vegetated corridor No barriers present
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50	URBAN WETLAND BUFFERS Urban buffers may be decreased by 25 feet if: the applicant implements all applicable mitigation measures identified in Table 2, or the applicant proposes alternate mitigation to reduce the impacts of the development and the department determines the alternative provides equivalent mitigation (buffer averaging, enhancement)
51	Wetland Buffer Reduction Options Buffer Width Averaging Decrease the buffer in one area and increase the buffer in another area of the wetland The new buffer will provide additional protection to wetlands or enhance their functions The total area contained in the buffer on the development proposal site does not decrease The additional buffer is contiguous with the standard buffer
52	WETLAND BUFFER REDUCTION OPTIONS Rural Stewardship Plan Applicable to sites zoned rural residential A commitment to provide better management of critical areas and natural resources than would otherwise be achieved through the CAO In exchange for increased stewardship an applicant may be eligible for buffer flexibility PBRS (Public Benefit Rating System)
53	WETLAND BUFFER REDUCTION OPTIONS Farm Management Plan Applicable for properties that are or will be predominantly used for agriculture Use best management practices developed for agriculture by the Natural Resource Conservation Service Farm Management Plan will protect critical areas and also support the viability of farm operations
54	WETLAND MITIGATION Prior to an alteration an applicant must apply the sequential measures Seven measures listed in order of priority First Measure is avoiding impacts altogether Second measure is minimize the impacts
55	SPECIFIC MITIGATION REQUIREMENTS On-site Based on ratios of mitigation to impact Re-establishment (restoration) – return historic functions - remove fill Rehabilitation – (restoration) – return historic functions – breaching dike Enhancement – Improve a specific function – planting native vegetation Creation – establish wetland on upland site
56	SPECIFIC MITIGATION REQUIREMENTS Off-site Mitigation off the proposal site Off-site mitigation will achieve equal or greater functions DDES in process of developing a resource mitigation reserve
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58	AQUATIC AREAS Includes existing stream regulations and adds lakes and marine shorelines – excludes wetlands Buffers will apply to large lakes and marine shorelines, which will pre-empt shoreline regulations New buffer widths
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60	TYPE S EXAMPLES Puget Sound Snoqualmie River Ames Lake Issaquah Creek
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64	TYPE F EXAMPLES Tuck Creek Mill Creek, Rock Creek All lakes and ponds smaller than 20 acres that contain fish or fish habitat.
65	TYPE N EXAMPLES The steep upper reaches (often seasonal and un-named) of other wetlands or fish bearing streams.
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68	AQUATIC AREA MITIGATION Prior to an alteration an applicant must apply the sequential measures Seven measures listed in order of priority First measure is avoiding impacts altogether Second measure is minimize the impacts
69	AQUATIC BUFFER REDUCTION OPTIONS Buffer Width Averaging Farm Plan Rural Stewardship Plan Alteration exception Reasonable use exception
70	RESOURCES Internet: www.metrokc.gov/ddes/cao www.ecy.wa.gov/programs/sea/shorelan Critical Areas Manual Rules for rural stewardship and farm plans Dedicated staff at DDES to assist rural landowners without charge Codified ordinance now available
71	QUESTIONS
72	BREAK
73	NEW CLEARING REGULATIONS Harry Reinert, Special Projects Manager, DDES Director’s Office
74	MAJOR CHANGES IN K.C.C. 16.82: CLEARING AND GRADING New permit exception table that tracks the new critical area alteration table New programmatic permits for activities that are repeated Seasonal clearing limits Soil retention requirements Class IV-G Forest Practices – Creates a special category of Class IV-G forest practice that is not a conversion to a non-forestry use Expand clearing limits to all rural residential areas Tree retention standards apply in all urban areas
75	DEFINITIONS Clearing – the cutting, killing, grubbing, or removing of vegetation or other organic material by physical, mechanical, or any other similar means Grading – any excavating, filling or removing of the duffer layer
76	CLEARING AND GRADING PERMITS Clearing and grading: Must meet requirements of clearing and grading code, even if permit not required If is proposed for a critical area or critical area buffer, must also meet critical area development standards Clearing and grading permit required, unless: Exception included on permit exception table Clearing and grading reviewed and approved by DDES as part of another development proposal Permits valid for up to two years, programmatic permits valid for up to five years
77	CLEARING AND GRADING PERMIT EXCEPTION TABLE New exception table describes when a clearing and grading permit is not required Tied to allowed alteration table in the critical areas ordinance
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79	SAMPLE CONDITIONS 1. Excavation less than five feet in vertical depth, or fill less than three feet in vertical depth that, cumulatively over time, does not involve more than one hundred cubic yards on a single site. 2. Grading that produces less than two thousand square feet of new impervious surface on a single site added after the effective date of this section. For purposes of this subsection C.2., "new impervious surface" is defined in K.C.C. 9.04.020. 3. Cumulative clearing of less than seven thousand square feet including, but not limited to, collection of firewood and removal of vegetation for fire safety. This exception shall not apply to development proposals: a. regulated as a Class IV forest practice under chapter 76.09 RCW; b. in a critical drainage area established by administrative rule; c. subject to clearing limits included in property-specific development standards and special district overlays under K.C.C. chapter 21A.38; or d. subject to urban growth area significant tree retention standards under section 17 of this ordinance and K.C.C. 21A.38.230.
80	Examples No clearing and grading permit is required to: remove noxious weeds remove downed trees outside of critical areas cut firewood for personal use in wetlands and aquatic areas
81	Examples No clearing and grading permit is required to: Clear for fire safety Up to 7,000 square feet of clearing in most areas In wetlands and aquatic areas, clearing following Fire Marshal BMPs Graze livestock Horticulture Maintain agricultural ditches (with a farm plan) Forest practices Maintain lawns, landscaping, and gardens
82	PROGRAMMATIC PERMITS Available for Clearing or grading that: is repetitive and part of a maintenance program; has the similar identifiable impacts; and standard permit conditions can be applied Forest practices under a county approved forest management plan DDES and applicant develop standard permit conditions Activities subject to inspection
83	EMERGENCY ACTIONS Notify department prior to taking action, or within 48 hours after, if prior notice not possible Requires imminent danger or risk to public health, safety and welfare of persons or property Permits, corrective action, and mitigation required following a pre-application meeting
84	EROSION AND SEDIMENT CONTROL Erosion and sediment control measures All clearing and grading requires erosion and sediment control, even if permit is not required Standards included in surface water design manual Seasonal clearing limits Applies county-wide From October 1 through April 30, clearing and grading allowed only if applicant demonstrates ability to comply with SWDM standards Director may modify the limitation period based on weather conditions Water quality violation results in a stop work order Does not apply to some routine maintenance activities, typical residential activities that do not require a permit, or emergencies
85	GRADING STANDARDS New requirements: Limits on type of fill material allowed Duff layer and topsoil retained if possible Cleared and graded areas must have soil moisture holding capacity restored to native site conditions
86	RURAL RESIDENTIAL CLEARING LIMITS Apply to all rural residential zoned property Clearing limits Lots less than 1.25 acres – greater of amount legally cleared prior to Jan. 1, 2005 or 50%. Does not include drain field and access Lots less than 5 acres – greater of amount legally cleared prior to Jan. 1, 2005 or 50% Lots 5 acres or larger – greater of amount legally cleared prior to Jan. 1, 2005 or 2.5 acres or 35% Subdivisions and short subdivisions – 35%; if placed in separate tract, 50% Bear Creek, Issaquah Creek, and May Creek Basins – 35% for lots greater than 1.25 acres
87	ACTIVITIES ALLOWED IN RETAINED AREAS Activities that will not prevent long-term purpose of promoting forest cover, including: Forest practices in accordance with a county-approved forest management plan; Passive recreation uses and related facilities, including pedestrian, equestrian community and bicycle trails, nature viewing areas, fishing and camping areas, and other similar uses that do not require permanent structures, Utilities and utility easements, including surface water facilities Pruning or removing hazardous trees or removing downed trees; Reducing the danger from wildfire by following best management practices approved by the King County fire marshal; Removal of noxious or invasive vegetation
88	SIGNIFICANT TREE RETENTION Applies inside urban growth area Defined as evergreens 8 inches in diameter and deciduous trees 12 inches in diameter Required to be retained If more than 25% of the site is in critical areas and buffers, provisions do not apply If retention on site is not possible, alternative off-site locations may be used
89	SPECIAL TIMING CONSIDERATIONS Clearing and grading code - legal clearing includes: Legal clearing before January 1, 2005 Clearing under a permit application complete by October 25, 2004
90	QUESTIONS
91	STEWARDSHIP AND INCENTIVE PROGRAMS Bill Eckel, Manager, Land and Water Stewardship Section, Water and Land Resources Division, Department of Natural Resources and Parks
92	TOPICS COVERED Purpose and the “big idea” behind Rural Stewardship Planning What Rural Stewardship Plans accomplish How WLRD staff will work with rural property owners Benefits
93	TOPICS NOT COVERED Farm and Forestry planning, which will be covered at a later date…
94	PURPOSE OF RURAL STEWARDSHIP PLANS Executive directed flexibility options; recognition that landowners are the best stewards of their land. Provide the same level of protection as regulatory standards – protections can be met with something other than uniform regulations.
95	PURPOSE OF RURAL STEWARDSHIP PLANS, Cont’d. Flexibility in meeting regulatory requirements means homeowners taking responsibility for long-term care of critical resources and their buffers. Only applied in rural residential zones – intended for single family home sites.
96	GOALS OF RURAL STEWARDSHIP Avoid critical areas where possible and protect the value they offer. Preserve the highest quality habitat first. Protect or improve the flow and absorption of water on site. Protect native plants and avoid fragmentation of corridors between wetlands, streams, etc.
97	GOALS OF RURAL STEWARDSHIP, Cont’d. Use “best management practices” to reduce impacts of a development, e.g. restoring native plants. Monitor, over time, what is working and what is not.
98	BENEFITS TO PROPERTY OWNERS Flexibility in meeting regulations Staff assistance Qualifying for property tax reduction
99	FLEXIBILITY IN KEY AREAS Wetland buffers Buffers for creeks, streams, rivers Buffers for regulated wildlife habitat areas for priority species Clearing limits
100	PUBLIC HEALTH AND SAFETY Standards are not flexible: Stay away from flood prone areas Stay off steep slopes, away from landslide hazards Protect critical groundwater recharge areas Building and sanitation code requirements
101	STAFF ROLES Property owners receive assistance from WLRD staff, free of charge. Staff person acting as your partner in developing plan, advocate during pre-application process. Available aerial photos and natural resource maps. Onsite field visits to assess property, permit needs and stewardship opportunities. Assistance in developing the plan, which could reduce the overall cost of a DDES permit.
102	PROPERTY OWNER ROLES Clearly state land use and stewardship goals for the property. Work with County staff in developing the plan. Coordinate any technical documents necessary to support the proposal. Submit final stewardship plan to DDES. Commit to long-term stewardship.
103	CURRENT USE TAXATION Property owner may qualify for reduction in property tax. Current Use Taxation program available throughout the state since 1972.
104	FOUR PROGRAMS IN KING COUNTY Forest land – timber forest greater than 20 acres (273,300 acres enrolled) Farm and agricultural land - livestock and farm products (30,900 acres enrolled) Timber land – 5-20 acres managed under forest stewardship plan (2,900 acres enrolled) Public Benefit Rating System (5,400 acres enrolled)
105	PBRS AND STEWARDSHIP PLANS Property owners with an approved Stewardship Plan may apply for a tax reduction, application fees have been waived. Points awarded according to open space resources: Natural resources Aquifer protection Forest and agriculture Stewardship plans Watershed protection areas
106	PBRS AND STEWARDSHIP PLANS, Cont’d Point totals translate into percent reduction of assessed value of the land dedicated to open space. Can range from 50-90% reduction. Home and building sites, landscaped areas, driveways and personal use areas are not eligible for reduction.
107	DECISIONS AND FACTORS Three criteria Condition of the buffer Health of the drainage basin Location in the drainage basin Land owner objectives – what to do on property and where Site specific best management practices Replanting natives Removing invasive plants More stormwater management Flexibility in clearing and with buffers
108	AREA WIDE CRITERIA Condition of the buffer If good condition, one might stay away from it Get greater flexibility in clearing If poor condition, look for replanting
109	AREA WIDE CRITERIA, Cont’d Location in the drainage basin Higher up the basin, looking for less of a stream buffer, but increases in forest cover. Lower in the basin, looking for improvements in the stream buffer and water quality.
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111	AREA WIDE CRITERIA, Cont’d Health of the drainage basin: Ranges from good, medium and poor based on rate of development patterns. Poor drainage basins will get greater flexibility with buffers, but increases in requirements to replant.
112	QUESTIONS Katy Vanderpool, Rural Stewardship Program Coordinator 206-296-8362 Katy.vanderpool@metrokc.gov Ted Sullivan PBRS Program Coordinator 206-296-6519 Ted.sullivan@metrokc.gov
113	BREAK
114	SEPTIC REVIEW REQUIREMENTS FOR SINGLE FAMILY PERMITS Steve Bottheim, DDES Critical Areas Supervisor
115	CRITICAL AREA DESIGNATION PROCESS
116	WHAT IS A CRITICAL AREA DESIGNATION? Review that enables applicant/property owner to determine the conditions and constraints on future site development (King County Code 21A.24.500-510). Establishes a site plan with boundaries and classification of critical areas Allows development planning with confidence and predictability Streamlines future building permit process. See Critical Areas Review Bulletin 21, available on the DDES Web site at www.metrokc.gov/ddes.
117	CHANGES WITH NEW ORDINANCE Required prior to health approval for new structures proposing to install on-site septic systems or wells Ability to include evaluation/interpretation of buffers, proposed alterations and mitigation Valid for five years Applies to existence, location and boundaries of Critical Aquifer Recharge Area as well as aquatic area, wetland , CARA, coal mine hazard, landslide and steep slope hazard Consolidated review option
118	DESIGNATION SCOPE Scope can be adapted to meet the applicant’s needs: Limited Scope addresses only those issues and that portion of the property requested by the applicant Comprehensive Scope addresses all critical areas in the proposed development area. (Required for projects that propose new on-site septic and/or wells.) The consolidated review option adds review of residential fire access, addressing, and site engineering, allowing all site issues to be pre-certified and vested
119	CONSOLIDATED SITE REVIEW “Permit in a box” for single family residential: Critical areas review Site engineering review Fire flow review Clearing limits Site requires no special exceptions Use preferred consultant $1,850 flat DDES review fee for critical areas, site engineering and fire flow
120	APPLICATION SUBMITTAL Site plan drawn to an engineering scale, with a north arrow, location and dimensions of all property lines and easements, including any known native growth protection easement areas or special setback areas. If designation is targeted on the parcel, identify and give dimensions of the area to be evaluated on the site plan. Identify any existing improvements, including structures and roads, on the property Show any known rivers, streams, swales, springs, seeps, wetlands, ponds, steep slopes or areas of saturated ground on the property or within 300 feet.
121	OPTIONAL REQUIREMENTS Topographic or boundary surveys Aerial photos Prior permits (building, grading, on-site septic or well etc.) or title notification of sensitive or critical areas, Special studies including: wetland reconnaissance reports, wetland delineations, aquatic area or stream reports, and geotechnical or soils reports Technical information reports or drainage studies A vicinity map showing the general location of the property. If the property is located in a difficult to find location, include driving directions.
122	DDES REVIEW Determine the type, location, boundaries and classification of any critical area on site (includes buffers from known adjacent critical areas) Determine if a critical area report is required Review reports Document the designation process to establish the classification and location of the critical area Applicant can request that DDES do a critical area report for wetlands/aquatic areas
123	DESIGNATION “PRODUCT” Letter with approved map documenting the location and classification of critical area and or buffer Project file established in DDES system for future permit reference Applicant records designation
124	FEES Fee varies according to nature of the request and the size and complexity of the property Deposit of $796.95 covers 5.5 hours of review (average review time for designations in 2004) Total fee based on the hourly rate of $144.90 and the actual review time Consolidated review option fee fixed at $1,850
125	QUESTIONS
126	CHANGES TO THE KING COUNTY DRAINAGE MANUAL Jim Chan, Supervisor, DDES Site Engineering and Planning
127	DRAINAGE MANUAL ADOPTION Adopted by public rule pursuant to King County Council adoption of the Stormwater Ordinance on October 25, 2004. Guidance draft of Manual update is posted at http://dnr.metrokc.gov/wlr/dss/Manual-Draft.htm. Stormwater Ordinance effective January 1, 2005. Public rule for Manual update effective since January 24, 2005. Manual update is available for distribution and purchase.
128	DRAINAGE MANUAL – AREAS OF SIGNIFICANT CHANGE Drainage Review Thresholds Best Management Practices (BMP) Erosion & Sediment Control (ESC) Special Requirements
129	DRAINAGE REVIEW THRESHOLDS New impervious surface threshold reduced from 5,000 SF to 2,000 SF, to apply BMPs to smaller projects. New threshold added for 7,000 SF of “land-disturbing activity” to improve erosion control.
130	DRAINAGE REVIEW THRESHOLDS, Cont’d. Threshold for large redevelopment projects changed per DOE Manual (i.e., ³ 5,000 SF of new + replaced impervious area and project costs ³ 50% of the assessed value. Transportation projects to be captured differently).
131	DRAINAGE REVIEW THRESHOLDS Sensitive areas threshold changed to flood hazard areas only, due to new 2,000 SF threshold. Small Site Drainage Review becomes Small Project Drainage Review, has new threshold, is no longer optional, and includes agricultural projects.
132	NEW FC BMP REQUIREMENTS FC BMPs (a.k.a. low impact development BMPs) required in addition to, and in the absence of, FC facilities on most developments. FC BMPs aim to prevent or reduce increased runoff at or near the source of that runoff.
133	NEW FC BMP REQUIREMENTS, Cont’d. FC BMPs include measures for increasing retention and/or infiltration of rainwater and minimizing developed surfaces and runoff. Facility sizing credits given for FC BMPs.
134	TYPES OF FC BMPs AND CREDITS
135	BMP IMPLEMENTATION REQUIREMENTS Implementation responsibility and provisions: For single parcel projects, applicant is responsible. For subdivision projects, lot-specific provisions must be made for future implementation by the home builder or lot owner.
136	BMP IMPLEMENTATION REQUIREMENTS, CONT’D. Declaration of covenant and grant of easement: Provide notice of BMPs & responsibility to maintain Reference and attach approved drainage plan Include operation and maintenance instructions Grant KC right of entry for inspection purposes
137	ESC CHANGES ESC supervisor certified and approved by the County. Sieve test replaced by turbidity test. Turbidity > 25 NTU requires additional action as deemed necessary by the ESC Supervisor.
138	ESC CHANGES, Cont’d. Turbidity > 100 NTU requires additional action as deemed necessary by the County. Measures added for construction site flow control, source control, and dewatering.
139	QUESTIONS Steve Foley: 206-296-1973 Kate Rhoads (water quality): 206-296-8046
140	THANK YOU