The US Coast Guard is investigating how the MV Sili suffered damage during its last trip to American Samoa's Manu'a late last week.
This leaves the Manu'a islands without a shipping service while the vessel goes on the slipway to be checked and fixed.
A Port Administration official said while the vessel was docked at Faleasao Harbor, strong wave action lifted it and slammed it down hard on the ocean floor.
Divers carried out an underwater survey of the boat on Saturday however the extent of the damage could not be determined.
The boat is going on the slipway for an inspection and repairs.
A private boat, the SV Adventurer plans to make two trips a week to Manu'a while the MV Sili is on the slipway.