The Joint Venture comprising of Cashman Dredging Inc. and Dutra Group was awarded last week a $122.2 million Boston Harbor dredging contract.
According to FedBizOpps, the project includes dredging of approximately 11,700,000 cubic yards of silt, blue clay, till and weathered rock from the harbor area.
The Federal Navigation Project for Boston Harbor consists of the following components: deepening and widening the Broad Sound North Channel to -51 feet Mean Lower, Low Water (MLLW), deepening and widening the Main Ship Channel (MSC) to the Conley Terminal including the turning basin or “MSC Notch” to -47 feet MLLW, deepening the President Roads Anchorage and deepening the lower Reserved Channel to -47 feet MLLW.
The improvement depths noted above are required to be an additional two feet deep in areas of hard material like till and weathered rock.
The Army Corps reported that the material dredged to create the federal navigation project improvements will be placed at the Massachusetts Bay Disposal Site (MBDS) approximately 20 miles offshore of Boston Harbor with the exception of a small fraction of the material being placed as a cap to the Main Ship Channel Confined Aquatic Disposal cell, just downstream of the inner confluence of the Chelsea and Mystic Rivers.
The contractor will be required to bring equipment to accomplish all dredging by mechanical means for the material types previously noted with strength characteristics less than fast rock. Dredging operations will be permitted 24 hours per day and 7 days per week and are expected to take up to 3½ years to complete, said USACE.