Contributed by Robert Lyman © 2018

Robert Lyman is an Ottawa energy policy consultant. He was a public servant for 27 years and prior to that a diplomat for 10 years.

The Trans Mountain Expansion Project involves a pipeline and marine component that has operated from around Edmonton, Alberta to the Vancouver and Puget Sound regions for 65 years. The project, if approved, would result in an increase of oil tanker traffic from 60 to 408 tankers per year (720 additional movements including in and out), in an area in which tanker traffic represents a small portion of the overall vessel traffic. The opponents to the project have attempted to focus attention on any and all aspects that might increase public alarm about the potential environmental impacts. The purpose of this article is to provide a “checklist” of points that counter the claim that the increase in oil tanker traffic resulting from the project poses an unacceptable risk.


  • While the port of Vancouver is one of Canada’s largest, by world standards it is not that busy. The port of Rotterdam in the Netherlands handles eight times the volume of vessel traffic and tanker traffic of Vancouver.


  • The volume of shipping traffic in the area of the project is only one of dozens of factors that affect the likelihood of a shipping incident, the possibility and volume of an oil spill, and the likely effects of a spill given all the precautionary and response measures in place. A thorough review of all these factors was conducted by the Transport Canada-led TERMPOL Review Process, using data and analysis from many sources including notably a study carried out by Det Norske Veritas (DNV). Readers interested in seeing all the technical details should consult the report of the TERMPOL Panel and the DNV report available online.


  • The tanker traffic associated with the project would use the Westridge Terminal, which is near the Port of Vancouver. The port of Vancouver now has about 23,000 ship movements a year, and is engaged in public consultations about plans to increase its size. This would add an estimated 5,000+ more ship movements a year if all the future upgrades were included. This dwarfs the 700 additional ship movements associated with the project.


  • DVR analyzed the risks associated with tanker traffic under three scenarios, one in 2018 without the project, one in 2018 with the project (i.e. assuming it was completed by then), and one in 2028 with the project.


  • Measured in terms of sailed nautical miles, in the first case Trans Mountain tankers would constitute 0.5% of the total 3.8 million miles by all vessels in the Salish Sea and Juan de Fuca Straight. Under the third scenario, in 2028, Trans Mountain tankers would constitute 3.0% of the 4.3 million miles by all vessels in this area. All oil tankers, including those associated with the project and others transporting crude oil and refined oil products would constitute 8.3% of the miles.


  • The DNV report concluded that the increase in vessel traffic resulting from the project would have “a negligible effect on the total incident frequency for the region”.


  • The TERMPOL Panel found that “the increase in large vessel transits is unlikely to pose a significant safety issue”.


  • The maximum size of the tankers calling at the Westridge Terminal will, as now, be Aframax class (80,000 deadweight tonnes to 120,000 deadweight tonnes), all double-hulled as required by international and Canadian standards.


  • The Termpol report found that, if all the risk reducing measures recommended were taken (they were subsequently made mandatory conditions of the National Energy Board certificate), the risk of a worst case oil spill (estimated to be 16,500 cubic metres) would be one in every 2,366 years. This is 30% higher than if the project did not take place. One should not make too much of this. Thirty per cent of almost zero is still almost zero.