Volume 2: Draft Gorst Planned Action Environmental Impact Statement

GORST PLANNED ACTION EIS | APPENDICESTable D-2. Potential Options to Standardize Gorst Creek Buffers in Gorst UGAOption / DescriptionDiscussionA. City SMP buffers50 foot buffer would apply in areasdesignated as Commercial.Areas designated as Single FamilyResidential would have a buffer based ontheir lot depth at either 20% or 30%,B. County SMP buffers200 foot buffer standard along all streamreachesC. Modified County SMP buffersApply buffers based on shorelineenvironment50 feet High Intensity100 feet Urban ConservancyD. Management Zone OverlaySee Table D-30-50 feet: focus on habitat retention andenhancement with limited trails50-85 feet: Allow small percentage ofimpervious or semi-pervious materials ifgreater enhancement in 0-50 foot area or ifstream restoration occurs.85-100 feet: Allow more impervious area ifgreater enhancement in 0-50 foot area or ifstream restoration occursFor the areas east of Sam Christopherson Road, this 50-foot buffer wouldrecognize the current development patterns where much area along thecreek is devoted to impervious area and structures.For the areas west of Sam Christopherson Road, designated for Single FamilyResidential, the buffers would be based on depth of the lot, to both protectthe immediate riparian area and allow use of the parcel for development;vegetation conservation and water quality standards would also apply.This appears to be an area identified for Restoration in the WatershedCharacterization Study.This buffer standard would treat all areas of the creek the same, regardlessof current conditions.Areas within the 200 foot buffer area (see Figure D-3) would need to applyspecial criteria for buffer reductions in Proposed SMP Section 5.5.3Constrained Lot and Infill Provisions. In some cases a variance may berequired and in other cases administrative approval is required. However,this overall approach could spur enhancement where some bufferreductions are granted with criteria; also, growth could occur more slowlygiven combination of regulations and site constraints.This buffer standard would recognize Gorst Creek as a different stream thanother shoreline streams in the County which tend to be in rural areas.The modified buffers would match Kitsap County’s buffers applied to specificshoreline environments rather than a single number.The modified buffers are similar to the City’s Commercial buffer and greaterthan (though more comparable to) the City’s Single Family ResidentialBuffer.The proposal would apply a series of management zones that have variablelevels of vegetation conservation, impervious allowances and structureallowances.The standards to retain vegetation and reduce erosion, minimize imperviousareas and structures, and incentivize restoration are based on theWatershed Characterization Study, and some of the buffer mitigationstandards in Kitsap County’s proposed Shoreline Master Program AppendixB.The distances of the management zones are related to the mean setback forshoreline streams and rivers (~78 feet) documented in the Kitsap CountyCumulative Impacts Analysis developed January 2013. The distances are alsobased on the buffer science and average distances in the “TechnicalMemorandum for Proposed Kitsap County SMP Buffers” prepared by KitsapCounty, January 2012 (which focuses on marine shorelines but providesscientific literature for both freshwater and marine shorelines).Table D-3, Gorst Creek Management Zones, provides more information on Option D. With this option, morealteration could occur in outer management zones than in inner management zones provided there isenhancement or stream restoration in inner management zones. These management zones could overlay on topof SMP buffers; the management zone approach would be most compatible in combination with Options A and C,but could work with Option B if administrative flexibility is offered to apply the standards.D-8