Volume 2: Draft Gorst Planned Action Environmental Impact Statement

GORST PLANNED ACTION EIS | AFFECTED ENVIRONMENT, SIGNIFICANT IMPACTS, AND MITIGATION MEASURESmanagement measures shown in Table 2-8 Integrated Watershed Processes and Habitat Results and ManagementMeasures.Possible plan features that would serve as mitigation for potential impacts to soil include the following:• Minimization of new development in certain areas.• Limiting logging activities and maintain appropriate zoning in areas with high sediment export.• Implementation of measures to reduce erosion and sediment export in areas identified for futuredevelopment (e.g., buffers, setbacks from steep slopes, reduction of overland flow through infiltration).• Restoration of cleared/degraded areas.• Implementation of stormwater retrofits to reduce impervious surface.Additionally, capital facility improvements have been recommended for addressing stormwater deficiencies andflooding issues. Implementation of these improvements would help reduce soil erosion and loss of soil from thewatershed. Based on policies in the proposed Draft Gorst Subarea Plan and Draft Gorst Creek WatershedCharacterization & Framework Plan implementing regulations could include a zero stormwater dischargerequirement limiting direct and untreated stormwater and a requirement that future development incorporate aseries of LID measures to infiltrate or detain runoff.Applicable Regulations and CommitmentsKitsap County CAO. Unincorporated portions of the watershed are under the jurisdiction of the Kitsap County CAO.These regulations may require a geologic or geotechnical report to be done to determine whether an areaproposed for development is a geologically hazardous area or area of geologic concern. A minimum buffer of 25feet beyond the top of the slope is required in all geologically hazardous areas, with larger buffers andbuilding/impervious surface setbacks required depending on the site and the degree of the hazard.City of Bremerton CAO. The majority of the watershed is under the jurisdiction of the City of Bremerton CAO.Additionally, the current Gorst UGA is likely to be under the jurisdiction of the City of Bremerton CAO as a result ofannexation within the time period covered by this EIS. All development projects with the potential to affect criticalareas in areas under the City of Bremerton’s jurisdiction require review for compliance with the CAO. The CAOprovides development standards that apply to geologically hazardous area, including buffers between steep slopesand structures/impervious surfaces. Applicants are required to mitigate for development in geologically hazardousareas by incorporating design techniques that minimize impacts to steep or unstable slopes and the risksassociated with these areas.KCC Chapter 12, Stormwater Drainage, and Kitsap County Stormwater Design Manual. Construction within areasunder Kitsap County jurisdiction is regulated by KCC Title 12. This section of the KCC requires erosion andsedimentation control measures for minor and major development, with major development requiring anapproved erosion and sedimentation control plan. This section of the code also requires that all site developmentactivities comply with the standards, specifications, and requirements of the Stormwater Design Manual. Minimumrequirements for major development include stabilization of exposed soils, slope stabilization, controls of off-siteerosion, as well as other requirements.BMC Chapter 15, SWMMWW and LID Guidance Manual. BMC Section 15 provides regulations for stormwatermanagement associated with new development and redevelopment. The code contains minimum requirementsfor small parcels and large developments, which includes BMPs and other means of controlling erosion andsediment during construction, permanently stabilizing soil during construction, and preparing a stormwatermanagement plan.The City of Bremerton has adopted the SWMMWW as the guiding criteria for planning, design, and construction ofstormwater facilities in Bremerton. The City of Bremerton has also adopted the LID Guidance Manual for KitsapDraft | June 2013 3-10