7200 HARDESON RD 2016-01-01 MF Import

t A a. � The following design flows for the downstream end of the project rc�ch were approved by the City of Everett: 2 year = 60 cfs 100 year = 200 cfs wWater quality is [air to good in Mcrrill and Ring Creek except during storm events. Limited data show elevated metals concentrations and high levels of suspended solids and °" silicon during major storm events. The elevated suspended solids are likely related to runoff ` from the existing gravei mine. 1�"� I.arge volumes of silt from the gravel mining operation have degraded downstream reaches of the creek. Moreover, pcak storm flows have increased erosion of thc channel �„ downstream of the site. The proposed development project would red�ce the runoff from the exposed area of the gravel pit and reduce sedimentation downstream. Runoff from the � developmenPs parking lots would be treated in grassed biofiltration swales to minimize the ,,,, impact of pollutants on the creek. The proposed stream restoration project would improve � water quality in the stream by further settling solids from suspension and providing shade for the stream. Overall, the development project, in conjunction with the restoration ,:, project, would improve water quality in the drainage. If the development and restoration ,., projects do not proceed, existing adverse impacts to water qualiry would continue. , � Project Goals and Objectives ;.. The goal of the proposed restoration project is restore and relocate the stream channel and stream corridor near Hardeson Road and thereUy cnhance and protect water "' qualiry in Merrill �nd Ring Creek downstream. The specific environmental objectives of the project are to: • establish a 60-foot cottidor of native vegetation that contains the stream; . maximize infltration throughout the restored stream reach; . protect the sewer line that has been exposed south of the property line; • provide an aesthetically pleasing corridor; . create riparian wetland suf�cient to mitigate the smail area of wetland affected by Phase 2 of the restoration project; 6 �