Ordinance 2910-06 - Laserfiche WebLink

wetland delineation and study must be completed by a biologist with expertise in wetlands in compliance with Chapter 37 of the Zoning Code. Wetlands can change over time and EMC. 19.37 requires use of the Washington State Wetland Rating System for Western Washington, rather than the Wetland and Buffer Functions Semi -Quantitative Assessment Methodology used in the EIS. (SEPA Land and Shoreline Use, Water, and Plant and Animal Policies) 2. Wetlands must be retained and buffers must be provided per the requirements of Chapter 37, or mitigation must occur. Where the applicant proposes alteration of the wetland or buffer, additional studies must be completed and the alterations must be approved by the Planning Director consistent with the standards in EMC 19.37. (SEPA Plant and Animal, Water, and Land and Shoreline Use Policies) 3. When an applicant proposes to fill or alter all or a portion of a wetland, the wetland replacement ratios shall be per the requirements of Chapter 37 of the Zoning Code. Table 4-1 provides a summary of potential wetland mitigations by basin. Note that where mitigation measures include raising the elevation of outlets in flow through riparian systems, the mitigation will be subject to site-specific analysis addressing the feasibility of the mitigation. The mitigation shall not be used for meeting on-site stormwater detention requirements. The intent is to create additional wetlands and increase the range of water depths to approximately .5 to 2 feet so that a mosaic of emergent, scrub shrub and open water habitat would be created. The intent is to significantly improve the habitat functions.2 The detailed wetland mitigation plan/report must demonstrate that wildlife habitat will be significantly improved by the proposed mitigation and that raising the outlet elevation will not result in degradation of the existing wetland. Mitigation must also be designed to ensure that stability of adjacent slopes is not impacted and that the mitigation will not adversely impact adjacent or downstream properties. (SEPA Land and Shoreline Use, Water, and Plant and Animal Policies) 2 Restricting the outlet can also significantly improve the water quality improvement functions, while also providing some stormwater detention function. However the mitigation cannot be used to meet required stormwater treatment and detention requirements. 10