Construction is underway at our Westridge Marine Terminal in Burnaby to build the new three-berth dock complex. Typical of waterfront construction, most activities will occur from the water using floating equipment such as marine derricks and barges.

A critical piece of construction equipment being used is the D.B. General, the largest floating and revolving derrick barge on the West Coast of North America. The crane’s maximum capacity is an impressive 700 tons, and the barge is more than 90 metres long and 30 metres wide.

The equipment was built for a dynamic environment and specially designed for heavy lifting, pile-driving and robust offshore construction. At Westridge, the crane will primarily be used to install the in-water piles to support the new berth structures, as well as the in-water circular sheet pile retaining wall.

The D.B. General made its way from Seattle, Washington, to Burnaby, BC, earlier this year, as there were no suitable Canadian vessels available to perform the specialized services required for the marine terminal expansion. Kiewit, part of the Kiewit-Ledcor Trans Mountain Partnership – the contractor building the Lower Mainland portion of the Project – applied for a coasting trade licence with the Ministry of Public Safety and Canada Border Services Agency in order to bring the foreign-flagged vessel into Canadian waters. The government granted permission, duties were paid and the crane was officially reflagged with a Canadian flag.

But, this isn’t the first time the crane has been used in BC waters. Kiewit used the D.B. General when they constructed the new Port Mann Bridge across the Fraser River, beginning in 2009. And, the federal government contracted the D.B. General to assist with the salvage of the Nathan E. Stewart tug off the coast of Bella Bella, BC, in 2016.

Trans Mountain is taking an innovative approach to help reduce noise from the D.B. General’s pile driving activities at Westridge Marine Terminal. To help us meet NEB Condition 80, contractors will be using a ‘noise shroud’ to cover the hammers that drive piles into the ocean floor, in addition to other mitigative measures.

The shroud, which is about two stories tall and wide enough to hold a medium-sized SUV, dampens the sound of hammer impact by 65 to 95 per cent. This is the first time this equipment has been deployed for a piling project in the Port of Vancouver. Bubble curtains will also be used around the piles to minimize noise travel underwater from pile-driving. These measures are designed to address the noise generated above and below the water, and are expected to reduce the overall potential for nuisance effects from the piling activity.