​​On November 15, 2024, about 1211 local time, the cargo vessel Belle Mer was anchored in the Tongass Narrows, near Ketchikan, Alaska, when the ship dragged anchor and damaged a subsea fiber optic cable. There were no injuries, and no pollution was reported. There was no damage to the vessel. Damage to the subsea cable was estimated at $240,000.

​We determined that the probable cause of the anchor strike of bulk carrier Belle Mer with the Alaska United Southeast Cable Segment 2 subsea fiber optic cable was the pilot and master’s choice to anchor near a known restricted anchoring area with inadequate anchor chain scope given the water depth and forecasted weather conditions. 

Contributing to the casualty was the Belle Mer crew’s improperly plotted drag circle, which was too large and, therefore, could not be used to effectively evaluate whether the ship was dragging anchor.

​Anchoring Considerations

When choosing a suitable anchoring location, mariners must consider many different criteria, including water depth, bottom type, proximity to hazards, weather, and available anchor chain scope. Holding power of the anchor and anchor chain also should be constantly analyzed while at anchor, especially under increasing external forces (such as wind and current) and while anchored near charted hazards. 

Additionally, drag and swing circles should be based on the actual anchor drop location and accurate vessel and anchor chain measurements. Once accurate drag and swing circles are plotted, mariners should continually monitor the vessel’s position with regular fixes compared to the plotted drag circle, swing circle, and available visual references.