News from the Puget Sound Partnership

Alicia Lawver
(360) 464-2011


Study measures potential risk from increased shipping traffic in Puget Sound

A recently released Vessel Traffic Risk Assessment (VTRA) study shows that three proposed maritime terminal developments could increase the risk of oil spills from vessel accidents. However, the study also shows that when a combination of management tools is applied to simulations of increased traffic, the potential for accidents could fall below the level regarded as the region’s baseline accident rate. The baseline was developed based on vessel traffic data collected in 2010.

The VTRA study focuses on evaluating how the risk of accidents and oil spills in Puget Sound changes when commercial vessel traffic increases. Scenarios looked at the risk associated with increases in commercial vessel traffic if three proposed projects take place. These projects were selected because they are in advanced stages of the permitting process and each would add hundreds of arrivals to the system each year.

•    The proposed Gateway Pacific bulk carrier terminal at Cherry Point, Wash.
•    The Trans Mountain/Kinder Morgan pipeline expansion in Vancouver, B.C.
•    The coal, grain and container terminal expansions at Delta Port, B.C.

Scenarios studied included risks associated with each project individually, as well as if all three projects were to be built. The steering committee—which included a variety of experts from the maritime community—helped guide the study, conducted by George Washington University and Virginia Commonwealth University. Steering committee membership included the U.S. Coast Guard, Puget Sound Partnership, Department of Ecology, Makah Tribe, local government, and several industry and environmental representatives from the Puget Sound Harbor Safety Committee. The study, which is not intended to demonstrate a position on any proposed project, was funded by the U.S. Environmental Protection Agency through grants to the Makah Tribe and Puget Sound Partnership.

“This is a foundational tool for considering various what-if scenarios, finding out how the probability of an oil spill could change if the scenarios being proposed became a reality,” said Scott Ferguson, Spills Prevention Manager with the Washington Department of Ecology. “The study explores what could happen if we add new vessel traffic to the system, and how we could manage that traffic in a way that reduces risk to our waterways and the ecosystem.”

The VTRA study is available at

About VTRA Study Area
The VTRA study area includes routes taken by commercial oil and cargo vessels from 20 miles offshore to more than 100 miles inshore to their ports of call in Washington and British Columbia. The Salish Sea region—which includes the Strait of Juan de Fuca, the Strait of Georgia, Puget Sound, and all connecting channels and adjoining waters in Washington and British Columbia—benefits from a comprehensive and continuously improving marine safety system. 

While the region has not seen a maritime oil spill of more than 10,000 gallons in almost 20 years, recent proposals to significantly increase the volume of oil, coal and other cargo shipped through the region have elevated concerns.

Between Washington ports and British Columbia ports, more than 4,000 deep draft commercial vessels arrive through the Strait of Juan de Fuca every year. Vessel routes may lead north through Haro Strait, Boundary Pass and Georgia Strait, or through Rosario Strait, or south to Puget Sound ports. A sizeable number of oil barges also travel between the ports of this region.

The VTRA study identifies potential outcomes if all three proposed terminals are fully developed without changing the risk management tools currently available:

How risk can be managed if the proposed projects are fully developed:
The study points out that rather than focusing any single way to lessen risk, U.S. and Canadian prevention efforts should look toward using a combination of management tools, as well as on improving current practices—such as vessel traffic management, vessel inspections, reduced vessel speeds and tug escorts.

By using a combination of risk management tools, the potential accident frequency could be reduced by as much as 11 percent even if no new terminals are built.

About the study
The VTRA Steering Committee and other interested parties met almost monthly from December 2012 through February of 2014, which resulted in finalization of the VTRA study. The purpose of the study was to improve the understanding of the associated risks with the marine terminal development projects and to make more informed decisions about risk management. A key motivation for the review and final report was to build upon the safety performance of the current system and to address risks of new proposed projects while identifying other continuous improvement opportunities.

Looking forward
The 2014 Legislature directed the Department of Ecology to complete a study of marine and rail traffic, and to develop recommendations for the Legislature and Governor to consider. That study will use the Vessel Traffic Risk Assessment final report as key findings for guiding the study.

About the Puget Sound Partnership
The Puget Sound Partnership is the state agency leading the recovery of Puget Sound. The Partnership coordinates the efforts of citizens, governments, tribes, scientists, businesses and nonprofits to set priorities, implement a regional recovery plan, and ensure accountability for results. The Puget Sound Partnership’s Oil Spill Work Group was formed in 2010 to provide independent advice and assessment of Washington’s oil spill programs and make recommendations for any necessary improvements. For more information, go to

About the Puget Sound Harbor Safety Committee
The Puget Sound Harbor Safety Committee provides a proactive forum for identifying, assessing, planning, communicating, and implementing those operational and environmental measures—beyond that which is in laws or regulations—that promote safe, secure, and efficient use of Puget Sound and adjacent waters. The committee is made up of delegates appointed by broadly based organizations representing a span of interests focused on Puget Sound. Various governmental agencies provide support for the work of PSHSC in advisory roles.

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