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

3.4 POST-DEVELOPMENT FUNCTIONS AND VALUES In order to accommodate a proposed development of the property suitable for a single-family residence and associated infrastructure on site, the applicant is proposing to fill the on-site wetland. Wetland A is a 3,432 square foot (0.079 acres) Category IV wetland located on the eastern side of the subject property, and is currently providing a low level of ecosystem functions and values. The on-site wetland and buffer are isolated from other critical areas, and are significantly impacted by invasive species including Himalayan blackberry and field bindweed. Well-established invasive species limits the quantity, density, and structural diversity of the native plant assemblage within the on-site wetland and buffer. Consequently, wetland functions and values including the attenuation of floodflow, biofiltration function, and the quality of wildlife habitat provided are significantly degraded. As compensatory mitigation for filling the low quality Category IV wetland on the subject site, the applicant is proposing to provide 5,162 square feet (0.12 acres) of wetland creation at the Mukilteo CAMP Mitigation Site M2. Additionally, the applicant is proposing to enhance a total of 6,649 square feet of buffer adjacent to the created wetland. 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. Utilizing the CAMP for mitigation will ensure that the biological and physical functions provided by the proposed wetland creation and buffer enhancement will occur within a sub-basin that has been identified as having a high ecological value. With the use of the CAMP the applicant will be filling a low quality largely isolated wetland on the subject site, while improving the size and function of Wetland 2, a dynamic high value feature that comprises a portion of the headwaters of Japanese Gulch & Brewery Creek. The proposed mitigation will result in long-term improvements to the overall level of critical areas functions and values within the larger City of Mukilteo watershed. 4.0 WETLAND MITIGATION PLAN 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 CAMP and provide wetland creation and buffer enhancement at the CAMP identified Mitigation Site M2:Japanese Gulch/Brewery Creek Headwater Wetlands. Mundorf-8th St 13 Critical Area Study & WRI#16233 Mitigation Plan March 2 0/6