Tug escort analysis

In 2019, the Legislature amended RCW 88.16 and RCW 88.46 to reduce threats of oil spills to Southern Resident Killer Whales. The amendments directed Ecology to develop an oil spill risk model and deliver two reports to the Legislature by September 2023: an analysis of an emergency response towing vessel (ERTV) for Haro Strait, Boundary Pass, and Rosario Strait; and an analysis of tug escorts for specified tank vessels. 

The tug escort analysis evaluated changes in oil spill risk by comparing the ability of tug escorts to respond when tank vessels lose propulsion and are in danger of drifting aground. We modeled three scenarios:

  • Scenario 1 simulated tug escort requirements in place prior to 2020. 
  • Scenario 2 added the new tug escort requirements required by RCW 88.16. 
  • Scenario 3 considered an expansion of tug escorts for specified tank vessels throughout the study area, which includes the inland Washington waters of the Salish Sea.

Final Report

The final report is available online here (link).

A correction statement describing a computing error we identified is available here (link). This error does not change the conclusions of the report.

Outreach and Consultation

During model and analysis development, we prioritized robust outreach with tribes, stakeholders, and the public. We held more than 25 events attended by more than 200 individual attendees affiliated with over 150 different organizations, and answered over 300 questions with real time and written responses.

Information about the events we held as part of model and analysis development are available online (link).