West Coast Spill Response Study. Volume 2

Posted July 19, 2013 | Categories : BC Parks,Management,Marine Reserves,Oil Spill Threat,Reports |

Volume 2 Vessel Traffic Study:

original PDF of Vol 2 published by the BC Ministry of the environment was at:

See the full PDF on this website at :WestCoastSpillResponse_Vol2_VesselTrafficStudy_130722

NUKAvol2iconThe British Columbia Ministry of Environment commissioned Nuka Research and Planning Group, LLC to prepare this report. The report is the second volume of the three-volume West Coast Spill Response Study. Volume 1 describes the current marine spill prevention and response system and Volume 3 describes one vision of the key features of a world-class system and suggests opportunities to enhance the system on the west coast of Canada.

This volume describes the general ports and operating areas that characterize western Canada’s marine waters,analyzes vessel traffic movements along the coast of BC for the 2011-2012 calendar years, and estimates vessel traffic volume as well as the quantities of petroleum transported as cargo and fuel.

Finally, potential future changes in this vessel traffic are tentatively forecasted. This report is the first such extensive analysis of vessel traffic performed for this area. It compiles three different sources of Automatic Identification System (AIS) data for the area, including satellite AIS, and brings in information on barge movements (not included in AIS data) based on data from the Canadian Coast Guard and key informant interviews. With AIS data, we were able to examine vessel movements instead of just port calls, thereby including vessels moving through the area to or from US ports in Alaska and, more significantly, Washington.

The movement of vessels with AIS transponders was compiled for six passage lines that essentially frame the BC coast. Key information was then collected for each vessel to ensure accuracy and allow us to analyze the specific vessel type, size, age, flag state,and other information for more than 54,000 vessel tracks across those passage lines over the two-year period.

The vast majority of vessel transits (78%) occur in southern BC through the Strait of Juan de Fuca at the Neah Bay and Point Roberts passage lines. This percentage is somewhat shaped by the fact that there is a high percentage of overlap between these two lines.

From 2011 to 2012, the volume of traffic across all passage lines increased by approximately 17%. These numbers are not necessarily indicative of longer-term trends, as they portray only two years of data. However, the increases in transits in 2012 compared to 2011 were most dramatic for Dixon Entrance, Alaska Inside Passage, and North Georgia Strait (though the latter may be related to improved AIS data collection, not necessarily an actual increase in transits).

An estimated 110 million cubic meters of petroleum per year move across the six passage lines used for this study in vessels other than tank barges, again primarily in the south. Persistent oil carried as bunker fuel (primarily in cargo ships) accounts for about 42 million cubic meters per year. About 38 million cubic meters of the total per year is persistent oil cargo, primarily Alaska North Slope crude oil being shipped to the refineries in Washington. About 25 million cubic meters per year of non-persistent oil is carried as cargo in tank vessels. Overall, the worse case spill from a single vessel would be the loss of 210,000 cubic meters  of crude oil from a tanker recorded as crossing the Neah Bay passage line en route to the US.
Additionally, the best estimate of oil moved by tank barge is 48 million cubic meters.

(including only outbound movements to account for the fact that barges are not always full) but this estimate is very rough compared to the estimates above which were derived from the AIS data. It also cannot be broken out by passage line.

While the overall vessel traffic is forecasted to remain much higher in the Vancouver area than farther north on the coast, the greatest changes could be seen based on potential traffic going in and out of Prince Rupert, Stewart, and Kitimat (again, depending on which projects go forward and which projects are proposed in the future which are not considered here). For example, tanker traffic in the south could more than double, while in the north it could go from being negligible to around 200 transits per year.

While Volume 1 of the West Coast Spill Response Study described the spill prevention and response system in place for the west coast of Canada today, this volume provides context for the vessel traffic for which that system is in place. Even taken together, the three volumes of the West Coast Spill Response Study do not constitute a risk assessment, but the information, particularly in this Volume 2, could be used to inform a future risk assessment that considers not only vessel traffic but the potential for different types of accidents and the potential consequences of a marine oil spill.

See Volume 1:

See Volume 3: