Report: Rescue Assets Key to Pacific Canada Grounding Risk
A new study, commissioned by Clear Seas and produced by Nuka Research and Planning Group, analyzes how ship routing combined with the location and availability of emergency tow vessels or rescue tugs might affect the probability of a disabled vessel drifting aground along the Pacific coast of Canada.
The authors concluded that, when considered in the context of generalized vessel traffic routes for the area, passenger vessels were the most likely to spend time within the area identified as having a 0-50 percent probability of rescue given their tendency to travel close to the coast. By contrast, once at sea, tankers stay the farthest offshore due to the voluntary Tanker Exclusion Zone.
The analysis clearly shows that significant reductions to the risk profile of the study area could be achieved through the acquisition and deployment of rescue assets, says Clear Seas.
In support, the report summarizes the outcomes of a scenario-based vessel drift and response analysis. The parameters that define the different scenarios were developed in consultation with Clear Seas and regional representatives of Environment and Climate Change Canada, the Canadian Coast Guard, Transport Canada and the British Columbia Coast Pilots.
Each of seven scenarios was run through a model to estimate the probability that a rescue tug would arrive in time to assist a disabled vessel. The model incorporates the coastline and historical wind conditions in the area and the time needed for a tug to reach the disabled vessel, which was calculated based on the tug’s starting location, mobilization time, travel speed, route and time to establish a tow line. The disabled vessel’s drifting time before grounding was calculated based on drift characteristics of particular vessel sizes and types that commonly transit the area, combined with wind conditions drawn from historical wind data.
The study is the first of three to be presented by Clear Seas as elements of the Marine Transportation Corridors project. The combined results of these studies aim to provide an enhanced understanding of some of the risks and potential prevention strategies associated with shipping activity on Canada’s Pacific coast. The approach developed for this study can be applied to all of Canada’s coastlines, says the organization.