The National Transportation Safety Board (NTSB) has determined that the probable cause of the towing vessel Schweiger striking the US Coast Guard (USCG) Station Cape Disappointment docks was the captain falling asleep at the helm.
The incident, which occurred on September 11, 2024, resulted in an estimated $750,000 in infrastructure damage.
The vessel was transiting lightboat through the Baker Bay West Channel near Ilwaco, Washington, when it veered out of the marked channel at approximately 12:36.
The Schweiger struck a wave barrier while travelling at seven knots (13 kilometres per hour), damaging a floating dock, timber pilings, and electrical and fuel systems.
Investigators found that the captain was suffering from an acute Covid-19 infection and a partially collapsed lung at the time of the voyage.
While the captain reported receiving adequate sleep in the days prior, the NTSB concluded that the illness likely resulted in poor sleep quality and increased fatigue, leading to the captain dozing off for one to three minutes.
The captain also admitted to taking unprescribed ivermectin the night before the accident to combat dizziness.
Although post-accident drug tests were negative for common substances, the NTSB noted that the potential neurotoxic effects of the unprescribed medication, combined with his illness, could not be ruled out as factors in his incapacitation.
About 20 gallons (76 litres) of diesel fuel spilled into the waterway from a severed pipe on the dock, but the Schweiger itself remained undamaged.
The NTSB issued a safety reminder to mariners to exercise caution when using medication and to remain aware of side effects that may impair their ability to safely operate a vessel.
