On March 22, 2021, at 0522 local time, the towing vessel Ava Claire was transiting with a crew of four westbound in the Gulf Intracoastal Waterway near Intracoastal City, Louisiana, pushing two fully loaded tank barges. After entering the Leland Bowman Lock at mile 163W, the bow of the lead barge struck a closed lock gate, damaging and disabling the gate. There were no reports of pollution or injuries. Damage to the lock gate was estimated at $2.5 million.
The probable cause of the contact of the Ava Claire tow with the Leland Bowman Lock gate was the towing vessel captain’s decision to assume the helm watch and attempt a predawn transit into the lock immediately after awakening while he was likely impaired by sleep inertia.
Sleep inertia is the temporary feeling of grogginess felt immediately upon awakening. Studies have shown that the effects of sleep inertia include reduced alertness, slower reaction time, less accuracy, degraded memory, and impaired decision-making ability. Sleep inertia generally lasts for about 30 minutes after waking but may last longer if a person is sleep deprived. Mariners should allow time to fully recover from sleep inertia before taking a watch and performing critical duties.