NTSB: watertight doors – vessel sank after flooding

  • Safety Flash
  • Published on 20 June 2022
  • Generated on 19 February 2026
  • IMCA SF 15/22
  • 2 minute read

The National Transportation Safety Board (NTSB) of the United States has published findings from an investigation into the flooding and sinking of a towing vessel.

What happened?

A towing vessel was in transit when its stern compartments began flooding. The three crew members aboard attempted to pump out the water but were unsuccessful and subsequently abandoned the vessel. They were rescued, and the towing vessel later sank close inshore. No injuries were reported. An oil sheen was visible after the vessel sank. The vessel was later recovered but was considered a constructive total loss valued at $968,000.

What went wrong?

Investigation determined that the probable cause of the sinking of the towing vessel was unsecured or open aft deck hatches, which resulted in the flooding of the vessel’s aft compartments from water on deck, leading to progressive flooding of other compartments through openings in watertight bulkheads. Contributing to the flooding of the vessel was the owner’s lack of an effective hull inspection and maintenance program.​

Lessons Learned

The NTSB noted that in the last five years it has investigated five casualties involving towing vessels whose weather decks and openings were in poor condition—leading to flooding and subsequent sinking.

  • To protect vessels and the environment, it is good marine practice for owners to conduct regular oversight, inspection and maintenance of hulls, including between drydock periods, regardless of inspection requirements.
  • An effective maintenance and hull inspection program should proactively address potential steel wastage, identify hull and watertight integrity deficiencies, and ensure corrosion issues are repaired in a timely manner by permanent means.​

Latest Safety Flashes:

Fall from height during mooring due to rope tension reaction

Rope became entangled with the propellor during mooring operations of a tanker causing the operator to lose balance and fall onto the lower platform.

Read more
Missing protection – progressive wear on hydraulic hoses causes damage

During an inspection, several hydraulic hoses and fuel hoses were found in direct contact with surrounding surfaces and sharp edges.

Read more
Small engine room fire – flammable object ignited

While ramping up the starboard main engine, a small flammable foreign object ignited.

Read more
Positive: damage to Fast Rescue Craft davit wire rope caught before failure

During routine checks, it was observed that the FRC davit wire rope had a visible fracture at the socket termination area.

Read more
BSEE: Miscommunication and trapped pressure causes injury during valve maintenance

BSEE has published Safety Alert 509 relating to a gas release incident on an offshore platform.

Read more

IMCA Safety Flashes summarise key safety matters and incidents, allowing lessons to be more easily learnt for the benefit of the entire offshore industry.

The effectiveness of the IMCA Safety Flash system depends on the industry sharing information and so avoiding repeat incidents. Incidents are classified according to IOGP's Life Saving Rules.

All information is anonymised or sanitised, as appropriate, and warnings for graphic content included where possible.

IMCA makes every effort to ensure both the accuracy and reliability of the information shared, but is not be liable for any guidance and/or recommendation and/or statement herein contained.

The information contained in this document does not fulfil or replace any individual's or Member's legal, regulatory or other duties or obligations in respect of their operations. Individuals and Members remain solely responsible for the safe, lawful and proper conduct of their operations.

Share your safety incidents with IMCA online. Sign-up to receive Safety Flashes straight to your email.