Posted on November 12, 2020
An investigation report [M19P0020] just released by the Transportation Safety Board of Canada raises important questions about the extent to which the increasing size of containerships poses a threat to safe berthing.
The report is into the TSB’s investigation into a January 28, 2019, incident in which the stern of the 7,042 containership Ever Summit slammed into the the berth at Vanterm, in the Port of Vancouver, British Columbia.
As the vessel was berthing, under the conduct of a pilot with two tugs assisting—one positioned forward, one aft—it struck the terminal and an adjacent gantry crane. The vessel, berth, and crane were damaged. There were no injuries or pollution.
The investigation found that the pilot’s and bridge team’s view of the tugs were obscured, and that the pilot was relying on his memory and mental model of the maneuver to keep track of the location and movements of the tugs. Intending to move the bow of the vessel towards the berth by ordering the forward tug to push and the aft tug to pull, the tugs were inadvertently given opposite commands. As the tugs carried out the commands, the vessel’s stern rapidly moved towards the berth. Corrective action was ineffective, and the vessel’s stern struck the berth and crane, causing the crane’s boom to fall on the vessel.
While the TSB report goes into detail about what went wrong on this particular occasion it includes a safety concern on the impact of container vessel size on the safety of berthing operations.
Here are some extracts:
“Over the past decade there has been a substantial increase in the size of container vessels worldwide, as well as those calling at container terminals in the Port of Vancouver. Larger container vessels have greater scantlings, deeper drafts, heavier displacements, and higher freeboards. As well, the hull at the waterline of newer container vessels tends to be more sculpted and finer form compared to traditional designs. This creates larger flares at the bow and stern, which necessitate approaches to the berth that are near parallel or “flat,” with very little tolerance for error.
“The report on the TSB simulation analysis of berthing conditions at Vanterm identified that a vessel of the Ever Summit’s size and design approaching the berth at Vanterm at an angle greater than 3° can result in the vessel contacting the berth, its fittings, or shore cranes, particularly at high tide. The investigation also determined that the energy absorption capacity of the fendering systems, the clearance between the waterside crane rail and the berth line posed hazards. These factors, as well as the suitability and location of mooring bollards and vessel spacing at the berth, need to be carefully evaluated, particularly in light of the greater displacements, length overall, and higher freeboards of large container vessels.
“All terminals have a maximum design vessel size and most have built-in safety margins to minimize the consequences of error. However, there are currently no requirements in place for any independent body, such as a port authority or Transport Canada (TC), to periodically examine or audit the suitability of a berth in relation to the maximum size of vessels berthing at a terminal and the berthing process. Decisions about the maximum size of vessels that are accepted are left to the discretion of individual terminals. This can lead to situations where vessels are calling at terminals that were not designed to accommodate them.”
“As the size of container vessels calling at the Port of Vancouver continues to increase and, given the absence of any oversight as to the suitability of the berths by TC or the Vancouver Fraser Port Authority, the Board is concerned that the size of vessels may exceed the Port of Vancouver’s terminal infrastructure capacity to accommodate them safely.”
Read the full report HERE.