COAL CREEK Sedimentation Reduction
Owner
Newport Yacht Club
Location
Bellevue, Washington
Erosion and flashy urban flows have created an accumulation of sediments at the mouth of Coal Creek on Lake Washington that block fish passage and increase turbidity. Scientists and engineers from The Watershed Company conducted site assessment, including hydraulic modeling, to determine the most effective solution. The team designed a herringbone scheme of logs to allow water, sediment, and fish to move to/from Lake Washington, eliminating the buildup of materials, allowing fish passage, and improving water quality.
Work was completed for private property owners living near the mouth of the creek as well as the Newport Yacht Club. The Watershed Company also assisted the yacht club with a comprehensive dredging project adjacent to the marina. A preliminary sediment sampling and analysis to remove approximately 30,000 cubic yards of sediment has been approved by the Corps, and conceptual removal plans are complete. We worked with the Washington State Department of Fish and Wildlife and the Department of Ecology to ensure that all appropriate environmental permits were obtained before dredging began.
SERVICES
Site assessments
Hydraulic modeling
Dredging
Sediment analysis
Environmental permits
