7609 44TH AVE W 2023-12-28 - Laserfiche WebLink

save for narrow strip of non-buffer area (437 square feet) along the western property boundary. As such, the on-site wetland and buffer restrict the applicant's economic use of the subject property. As a means of providing a developable lot for a new home to be built at a size commensurate to the existing neighborhood residences, the applicant is proposing to fill the on- site wetland and provide compensatory mitigation through off-site wetland creation in a high- value watershed. Lot development will result in permanent impacts to 3,432 square feet (0.079 acres) of Category IV wetland(City of Mukilteo and DOE rating). As compensatory mitigation for filling the low quality Category IV wetland on the subject site, the applicant is proposing to utilize the City of Mukilteo Critical Areas Mitigation Program (CAMP) and provide wetland creation at the CAMP identified Mitigation Site M2: Japanese Gulch/Brewery Creek Headwater Wetlands. The selection of Mitigation Site M2 is appropriate for the proposed project as both the impacted wetland and Site M2 in which wetland creation and buffer enhancement is proposed, are within the same drainage sub basin. The applicant is proposing to create a total of 5,162 square feet of wetland (1.5:1 creation to fill ratio) at Mitigation Site M2, as mitigation for the 3,432 square feet (0.079 acres) of permanent on-site wetland fill. Additionally, as compensatory mitigation for the loss of 6,609 square feet of regulated buffer area, the applicant is proposing to enhance a total of 6,649 square feet of buffer at Mitigation Site M2 with an assemblage of native trees and shrubs (1:1 enhancement to impact ratio). This buffer area currently has low structural diversity and is dominated by Himalayan blackberry, an invasive species. The enhancement of the degraded buffer area, and establishment of a structurally diverse assemblage of native plants,will improve the attenuation of floodflow, biofiltration function, and the quality of wildlife habitat provided within the Mitigation Site M2. Site M2: Japanese Gulch/Brewery Creek Headwater Wetlands, is identified in CAMP as a potential mitigation site ideal for wetland creation, wetland enhancement, and buffer enhancement. Additionally, there is opportunity for the removal of a paved roadway, as well as invasive species eradication in upland areas. The applicant is proposing wetland creation contiguous with the feature identified as Wetland 2 described in the CAMP document. Wetland 2 is a palustrine open water/forested wetland less than 0.5 acrein size, located in a depression in the northeast portion of the property. The majority of the wetland is located off of the property, with approximately 0.01 acre of wetland located on the property. The wetland generally occurs within an oblong depression and hydrology is likely supplied by a combination of direct precipitation and groundwater. Dominant vegetation in the wetland includes red alder and salmonberry. The 5,162 square feet of wetland creation represents a 1.5:1 creation to impact ratio as required for permanent impacts to Category IV wetlands by the City of Mukilteo (MMC 17B.52B.100(B)(2) Table 2) and the Washington State Department of Ecology. Utilizing the CAMP program for mitigation is consistent with the document, Selecting Wetland Mitigation Sites Using a Watershed Approach (DOE Publication #09-06-032 , and will ensure that the biological and physical functions provided by the proposed wetland creation will remain within a high value sub-basin, contained in the larger City of Mukilteo watershed. 2