NTSB published its report of the grounding of a fishing tender during a storm near Bristol Bay, Alaska in 2020. “SM 3” was anchored and riding out a storm with a crew of six in Nushagak Bay, 5 miles south of Ekuk, Alaska, when the barge broke free from the buoy and began drifting.
The incident
On May 21, 2020, in anticipation of the opening of the 2020 salmon season in Bristol Bay on June 1, the SM-3 was positioned in Nushagak Bay, 5 miles southeast of the village of Ekuk, along with its two support vessels: the 150-foot-long cargo holding barge Riverways-11 and the 70-foot-long workboat Sea Mount.
With the assistance of a tugboat, the SM-3 was anchored using its mooring and ground tackle system. The SM-3 and the Riverways-11 were connected bow-to-bow with lines, and a ramp was used to drive fork trucks between them.
About 2.5 months after the season began, on August 19, the SM-3 ended major fish operations with 17 crewmembers on board. The crew took the next few days to freeze and move fish, wrapping up the season.
By August 23–24, all but eight crewmembers had been paid and sent home. The remaining crew, which included the PIC, senior deckhand, operations manager, fish house manager, and two deckhands on the SM-3, and a captain and deckhand on the Riverways-11, began preparing the barges for winter layup.
The PIC and IT manager discussed their need for a 3-day window of good weather to move both barges to their separate winter layup locations.
On Tuesday, August 25, the National Weather Service (NWS) in Anchorage, Alaska, identified a storm that was forecasted to produce storm-force conditions and potential hurricane-force winds at the end of the week.
At the same time, the company and the SM-3’s crew began tracking the storm using a free weather-monitoring application, which visually depicted current and forecasted winds, waves, and precipitation but did not include NWS advisories/warnings and did not have archive capability. The PIC said that about 3-4 days out, predictions firmed up that the storm would come through the area.
The company president stated that he and the PIC discussed whether to move the Riverways-11 or leave the two barges connected. Because the two barges had not ridden well while tied together in one instance of rough weather earlier in the summer, the PIC did not believe they would do well together in the upcoming storm.
There was only one towboat close enough to tow the barges, and since the Riverways-11’s regular layup location was closer than the SM-3’s, the president and PIC agreed that the Riverways-11 would be towed away for layup.
They decided that the best option for the SM-3 was to ride out the storm at anchor in the relative safety of Nushagak Bay because there was not enough time to retrieve the SM-3’s ground tackle system, then safely tow the SM-3 to its winter layup site across the unprotected Kvichak Bay.
In the early morning of August 27, the Riverways-11’s emergency anchor and cable were put on board the SM-3, and the holding barge’s mooring buoy chain was attached to the SM-3 at the bow. A contract towing vessel towed the Riverways-11 to Dillingham for winter layup.
On August 30, the wind picked up in the afternoon as predicted. The PIC estimated winds at 50 or 60 mph (43 or 52 knots), and he stated that after a lull, the full
effect of the storm was upon them.
Recorded observations at the airport at Clark’s Point showed sustained winds from the south-southwest over 30 knots for about 7 hours, with maximum sustained winds at 41 knots at 1630 and wind gusts over 50 knots for about 3.5 hours.
In the galley on the berthing deck, the crew secured equipment on wheels that began to move. Additionally, to prevent water damage, the generator on the main deck was secured and the load transferred to the backup generator in the engine room.
The IT manager said the crew initially stayed in the galley, watching waves break over the bow; when it was too dark to see, they went to the recreation room. The depth at the anchorage was about 40 feet, and the PIC estimated seas in the area were 8–10 feet.
About 2300, the PIC was awoken by a “motion change in the barge;” he stated that he knew immediately that the barge was drifting. He went to the recreation room and told the crew the barge was no longer connected to the mooring buoy. The PIC, IT manager, and operations manager went out on deck to the stern and observed the SM-3 port side to the wind and waves, drifting toward a beach that was 2.1 miles to the east of where they had anchored.
They went to the barge’s stern to release the emergency anchor, and the PIC estimated that, about 5 minutes after noticing the drift, the first emergency anchor was let go from the stern with 900 feet of steel cable.
The SM-3 swung around so that the barge’s stern was facing into the waves, but it continued to drift. The IT manager stated that the emergency anchor did not “slow down [their] movement towards shore at all.”
The PIC, IT manager, and operations manager, joined by the fish house manager and a deckhand, next began working to deploy the second emergency anchor. They used the barge’s cranes to move the emergency anchor and shackle it onto the first emergency anchor’s 900-foot-long steel cable.
About 25 minutes after the SM-3 began drifting, the second emergency anchor was deployed from the stern down the steel cable using the deck cranes. The operations manager stated that, with both emergency anchors deployed and both cables under strain, he thought the anchors held for a moment, but then the barge continued to move toward the beach, so the crew took shelter in the fish house.
About 5 minutes later, the SM-3‘s bow grounded on Flounder Flat, a sandy beach. Incoming waves turned the barge starboard side to the shore with a slight list to port.
The PIC estimated that after about an hour in the surf, the freezer unit over Bay 1 (the engine room) broke away, and water from the main deck splashed down on the generator control panel.
At the same time, the barge’s slight port list suddenly shifted to about 10° to starboard, and the fish house gave way. The crew moved forward to Bay 3, and the PIC secured power to the generator and closed the watertight doors on the lower deck. With the SM-3 still surrounded in heavy surf, the wracking stopped, and the barge settled on the beach.
Probable cause
The National Transportation Safety Board determines that the probable cause of the grounding of the fishing tender barge SM-3 was a fatigue crack in one of the mooring buoy’s padeye welds, which resulted in the padeye separating from the buoy’s spherical steel plating, causing the barge to break free from its buoy and anchors and drift ashore during a storm.
Lessons learned
In addition to fitting mooring chains of sufficient length to provide adequate scope for anchorages, mariners must consider the strength of each component of a ground tackle system and should reference marine standards for design.
Bending loads can be significantly higher than straight-line pull. The working load limit of each component should be equal to or greater than the ground tackle system’s maximum calculated load to avoid weak points in the system.
EXPLORE MORE AT NTSB’S REPORT ON SM-3
