Collision risk in the approaches to the Strait of Juan de Fuca: An analysis of circumstances and traffic routing

Marine traffic casualties in the approaches of the Strait of Juan de Fuca risk the accidental release of oil or other hazardous liquids which threatens the loss of property, human life and the spoiling of the coastal zone. Traffic in the approaches to the Strait has increased at three percent annually from 15 828 vessel transits in 1980 to 19 887 transits in 1989. This traffic carries as fuel about 40 percent of the total volume of crude oil transported from Valdez, Alaska to Puget Sound by about 333 tankers annually. Collisions are of particular concern as they accounted for 83 percent of those casualties caused by human error. The problem of marine collisions in the approaches to the Strait of Juan de Fuca was investigated with the purpose of identifying causal and contributory factors, modelling collision risk as a Poisson distribution, and designing an alternate traffic routing scheme intended to reduce casualties.; Since the collision rate is correlated with average traffic densities encountered and ship-miles, it can be predicted and reduced through the modification of traffic patterns. (Abstract shortened by UMI.)...