Marine transportation safety investigation M19P0279

This is the summary of a class 5 occurrence to which TSB investigators deployed. The investigation is now closed.


Rail barge Nana Provider (United States official number 1197833)
Discovery Passage, British Columbia

The occurrence

On at 2330,Footnote 1 the tug Polar King departed Seattle, Washington, for Whittier, Alaska, with the rail barge Nana Provider in tow (Figure 1). The length of the towline was approximately 800 feet. The route was planned via the Inside Passage with an estimated time of arrival (ETA) for Cape Mudge, British Columbia (BC), at 1930 on 09 November 2019.

Figure 1. Rail barge Nana Provider (Source: TSB)
Rail barge Nana Provider (Source: TSB)

All the watch keepers held pilotage exemption certificates issued by the Pacific Pilotage Authority, and the wheelhouse was manned by 2 people, the watch keeper and a lookout, while the vessel transited Canadian waters.

The tug crew’s intention was to transit Seymour Narrows at slack water, which was forecast for 2135 on 09 November.

Due to other traffic also transiting the narrows, the ETA for Seymour Narrows was subsequently amended to 2110. The tug with barge in tow passed the Cape Mudge traffic call-in point at 1933. As there was ample time to make the 2110 ETA for Seymour Narrows, the tug was proceeding at reduced speed and made some course adjustments. At 1949, while the tug was transiting Yaculta Bay, BC, on a heading of approximately 275° true (T), the barge, under the influence of the current, grounded in position 50°01.944′ N, 125°12.859′ W. The tug was making good a course of approximately 305°T at the time.

Upon grounding, the tug released the entire tow line into the water. The efforts to refloat the barge during the subsequent high tide were unsuccessful. The barge was eventually refloated on 15 November 2019 with the assistance of a salvage company and towed to Duncan Bay, BC. There was no reported pollution or injuries. The barge sustained damage and water ingress into 4 void spaces and ballast tanks.

Class of investigation

This is a class 5 investigation. Class 5 investigations are limited to collecting data, which are then stored in the modal database. If TSB investigators deployed to the occurrence site, a short description of the occurrence will be added to this page once the investigation has been completed. These investigations are generally completed within 90 days. For more information, see the Policy on Occurrence Classification.

TSB investigation process

There are 3 phases to a TSB investigation

  1. Field phase: a team of investigators examines the occurrence site and wreckage, interviews witnesses and collects pertinent information.
  2. Examination and analysis phase: the TSB reviews pertinent records, tests components of the wreckage in the lab, determines the sequence of events and identifies safety deficiencies. When safety deficiencies are suspected or confirmed, the TSB advises the appropriate authority without waiting until publication of the final report.
  3. Report phase: a confidential draft report is approved by the Board and sent to persons and corporations who are directly concerned by the report. They then have the opportunity to dispute or correct information they believe to be incorrect. The Board considers all representations before approving the final report, which is subsequently released to the public.

For more information, see our Investigation process page.

The TSB is an independent agency that investigates air, marine, pipeline, and rail transportation occurrences. Its sole aim is the advancement of transportation safety. It is not the function of the Board to assign fault or determine civil or criminal liability.

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