The applicant proposes to mechanically dredge, using an environmental clamshell bucket, an approximately 76-foot wide by 540-foot long area to a depth of 4-feet below the plane of Mean Low Water with 2-feet of allowable overdepth dredging. During the initial dredging cycle, approximately 5,000 to 7,500 cubic yards of sediment would be dredged. During subsequent years, approximately 1,000 cubic yards would be dredged. During dredging operations, a silt-screen would be used to confine turbidity within Cowan’s Canal. Material in loaded scows would settle at least 24 hours prior to decanting of excess water to Cowan’s Canal and be transported to a state-approved upland facility. Work would also entail repair and/or replacement of approximately 453 feet of timber and sheetpile bulkhead, resulting in a net increase in open water area of approximately 330 square feet.
The purpose of this project is to provide safe navigation and mooring for barges at a material processing facility.