Tanker in Prince William Sound

Study evaluates places of refuge

By Alan Sorum
Council Project Manager

Some locations won’t work for Prince William Sound tankers

A recent Council-sponsored study reviewed eight “potential places of refuge,” or PPOR, which are locations where an oil tanker in distress can anchor and take action to stabilize its condition. Of the eight reviewed in the study, none were found to be safe for use by tankers. However, several safe alternates were identified, analyzed, and proposed for future consideration.

Identifying these sites in advance allows decision-makers to save time during their critical initial response to a potential oil spill. Establishment of these places of refuge is recognized by the International Maritime Organization and other governmental agencies as an important marine safety and pollution mitigation measure.

The Council partnered with the Alaska Department of Environmental Conservation in 2004 to develop a matrix listing potential places a vessel in distress could shelter from weather and rough seas. A review of the department’s website showed that information developed in the 2004 effort has not been updated since it was published.

Technology helped safely evaluate locations

Working with the Alaska Maritime Training Center at AVTEC – Alaska’s Institute of Technology in Seward, Alaska, the Council sponsored development of a high-resolution navigational dataset for Prince William Sound in 2014. This upgraded navigation information, along with AVTEC’s simulators were used to verify the safety of eight sites in Prince William Sound that had previously been identified as PPOR for crude oil tankers.

Beginning in September of 2015, the Council started working with Safeguard Marine, LLC to evaluate the safety of eight of the places of refuge in Prince William Sound. Seven others have already been used by tankers and are known to be safe.

Safeguard Marine evaluated the sites using interviews with local subject matter experts and stakeholders and simulated ship maneuvers. The maneuvers were conducted by members of the Southwest Alaska Pilots Association using models representing Trans Alaska Pipeline System crude oil tankers in varying degrees of distress. Determining whether the PPOR is safe for the oil tanker in distress is a function of whether the vessel could potentially run aground if there is insufficient swing room when anchoring or mooring.

The Council has asked the U.S. Coast Guard and DEC members of the Alaska Regional Response Team to consider the recommendations developed in the study in future updates.

Establishment of preplanned places of refuge provide communities, regulators and industry a chance to consider local knowledge and conditions prior to a crisis. An accurate PPOR matrix provides the Coast Guard Captain of the Port with an additional tool in the decision-making process associated with placing a vessel in sheltered location. Gathering information on potential sites from stakeholders in advance of an incident is always a preferred planning approach and furthers the Council’s stated mission of promoting the safe transportation of crude oil thorough Prince William Sound.


Full report by Safeguard Marine, LLC:

Ship Simulation and Mariner Study of the Maritime Implications for Tank Vessels Utilizing Potential Places of Refuge, Mid-Prince William Sound Alaska (1.4 MB)

Skip to content