2025-03-10: A quick report on the tanker collision in the UK's northern waters

I. Background

On 10 March 2025, at 10:00 UTC, in the waters of the North Sea of the United Kingdom, the container ship Solong, flying the Portuguese flag, and the chemical tanker Stena Immaculate, flying the United States flag, collided with each other at a speed of 16 knots (approximately 18 miles per hour). Both ships caught fire after the collision, causing explosions and fires for more than 24 hours, with multiple people abandoning the ships to escape. The Humber Port Authority, where the accident took place, announced an indefinite closure, resulting in the suspension of Europe's largest ro-ro vehicle terminal.

The Stena Immaculate, which is 183 meters long, is part of the United States Government's tanker safety program. The United States Department of Defense confirmed that the tanker was carrying fuel for a NATO military base. It was carrying 220,000 barrels of Jet-A1 fuel in 16 tanks, at least one of which is currently ruptured.

Accident location and image (image from abcNews)

**2. Progress of the incident** Stena Immaculate is still anchored in the area with normal AIS signals. Solong's AIS signals have disappeared and it has lost power and drifted south. On 11 March, UK officials stated that the Solong container ship may sink. On 11 March 2025 at 13:00 UTC, Mullem, a German vessel fitted with anti-fouling devices and equipment, arrived at the accident area and continued to operate in the area.

Trajectory of the anti-fouling vessel Mullem

**3. Remote sensing monitoring of the incident** Remote sensing imagery on 11 March shows that the Stena Immaculate is still anchored at the incident site and that no traces of oil spill have been detected in the surrounding area. However, the Jet-A1 fuel it carried and leaked is usually transparent or straw yellow in color, which is difficult to distinguish from seawater on remote sensing images. Therefore the true extent of the spill and the environmental impact remain to be further assessed. It is of concern that Solong is currently drifting southwards, posing a safety risk to ships travelling in and out of the Humber and to the extensive wind offshore farms to the south, and requires ongoing attention.

Remote sensing imagery on 11 March

**Source:** Xinrong Yan, Jing Bai, China Waterborne Transport Research Institute Juanle Wang, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences