Events in the subsea sector that marked 2023

As we gradually shift our focus on the new year and on what lies ahead in the offshore energy industry in 2024, let’s give a last look to 2023 to pay tribute to this very eventful year. Unfortunately, the year was marked with a number of dark events, with the Balticconnector offshore gas pipeline incident taking the majority of attention.

Balticconnector was shut down at midnight on October 8, 2023, after Finnish and Estonian transmission system operators (TSOs) Gasgrid and Elering observed an abnormal pressure drop shortly before 2 a.m., suspecting that there was a leak in the pipe.

Following the launch of an investigation, Finnish authorities reported that the damage was not caused by the normal gas transmission process and that it is likely that the damage to the gas pipeline was caused by external activity. The NORSAR research foundation which specializes in seismology and seismic monitoring later reported that it had recorded seismic signals near the gas pipeline that indicate a possible explosion occurred at around 01:20 on October 8.

Finland’s National Bureau of Investigation (NBI) clarified the cause of the damage, stating that the Newnew Polar Bear vessel, flying the flag of Hong Kong, is believed to have caused the damage after an anchor was found a few meters from the gas pipeline damage point.

Norway’s Statnett reported on June 8, 2023, that a fault caused the unavailability of the 1,400 MW North Sea Link (NSL) that connects the UK and Norway, causing the interconnector to operate at half capacity.

It was later reported that the cable fault occurred due to a technical fault in the rectifier system.

The link that runs between the Suldal municipality in Norway and the Newcastle area in England returned to full operations on June 13 following the repair.

UK-headquartered energy services provider Expro reported that on September 19, 2023, an incident occurred in Australian waters which saw a subsea module, associated umbilical lines and a crane wire sink to the bottom of the sea due to a wire failing on the main crane of a vessel.

The wire failed on the main crane of a third-party-owned vessel while it was suspending the subsea module of Expro’s vessel-deployed lightwell intervention (LWI) system. At the time of the failure, the subsea module was suspended approximately 15 meters above the seabed. As a result, the subsea module, associated umbilical lines, and the severed crane wire descended to the seabed.

Luckily, no personnel were injured during the incident and an initial ROV survey has confirmed that the equipment came to rest at a safe location on the seabed.

A big success story took place in the first half of 2023 when Fugro located the wreck of the Montevideo Maru World War II ship 81 years after sinking, reported as one of the worst international maritime disasters in history.

The Dutch company started the search for the transport ship on April 6, 2023, onboard the hydrographic survey vessel Fugro Equator. Deploying an autonomous underwater vehicle (AUV) with an in-built sonar, a positive sighting of the Japanese ship was recorded 12 days later at a depth of more than 4,000 meters off the coast of the Philippines.

Verification of the wreck came a few days later from the project team.

The Montevideo Maru was carrying approximately 1,060 war prisoners and civilians when it was sunk by an American submarine in 1942 during World War II. The tragedy resulted in fatalities from at least 14 countries, including Australia, Denmark, England, Estonia, Finland, the Netherlands, Japan, Ireland, New Zealand, Norway, Scotland, the Solomon Islands, Sweden and the U.S.