What’s That Enormous Structure Out at Sea? The Fascinating Story Behind the Giant Rig Off the Formby Coast

Anyone looking out towards the Irish Sea from Formby, Ainsdale or Southport may have noticed an enormous industrial structure towering above the horizon. But what exactly is it, and why is it there?

Some residents have wondered whether more offshore wind turbines are being installed, but the truth is rather more interesting, as the enormous structure is connected to major changes taking place beneath Liverpool Bay.

The structure has been identified as the ENSCO 120, a giant mobile offshore drilling rig operating in the Irish Sea.

Photographs taken from Ainsdale Beach show the impressive installation standing on the horizon, with its enormous steel legs and drilling equipment clearly visible from the shoreline.

And following our investigations, we have discovered that the rig is operating in an area undergoing one of the North West’s most significant offshore energy transformations.

What exactly is the ENSCO 120?

The ENSCO 120 is a mobile offshore drilling platform known as a jack-up rig.

Built in 2013, the enormous structure measures approximately 102 metres long and 80 metres wide.

Unlike permanent offshore platforms, the ENSCO 120 can be moved between different locations.

Its three towering steel legs are lowered towards the seabed, allowing the main platform to be raised above the waves to create a stable working environment.

This enables drilling operations to take place in offshore conditions where an ordinary floating vessel would struggle to remain steady.

Although it appears relatively small when viewed from Formby or Ainsdale Beach, the installation is actually longer than a football pitch.

Is it installing more wind turbines?

Following questions from residents, we can confirm that the ENSCO 120 is not a wind turbine installation vessel.

Although its enormous legs may make it resemble the vessels used to construct offshore wind farms, this particular structure is designed for drilling wells beneath the seabed.

Its presence in Liverpool Bay is associated with existing offshore energy infrastructure rather than the installation of additional wind turbines.

A major carbon storage project beneath Liverpool Bay

What makes this story particularly interesting is the enormous transformation currently taking place in Liverpool Bay.

For decades, the Irish Sea off the Sefton coastline has been home to offshore oil and gas production.

However, the area is now becoming central to a major carbon capture and storage development known as HyNet North West.

The project aims to capture carbon dioxide produced by industrial facilities across North West England and North Wales, preventing it from entering the atmosphere.

Instead, the captured carbon dioxide will be transported through a network of pipelines and stored permanently in depleted natural gas reservoirs deep beneath Liverpool Bay.

These underground reservoirs previously held natural gas for millions of years.

The project involves adapting existing offshore infrastructure, drilling and modifying wells, and constructing new facilities to transport and store carbon dioxide.

The ENSCO 120 has been associated with drilling operations within this offshore development area, although its precise current assignment has not been independently confirmed.

An important announcement this week

An official marine notice published on Tuesday 3 November 2026 has revealed that the ENSCO 120 is due to move between two locations in Liverpool Bay.

The notice confirms a planned relocation from the Hamilton East wellhead to the Lennox subsea well.

Both locations are associated with the area’s established offshore gas infrastructure.

The Lennox reservoir is also one of the locations identified for future carbon dioxide storage as part of the Liverpool Bay development.

Although an exact date for the rig’s relocation has not been confirmed, the announcement suggests that residents may notice changes to the structure’s position on the horizon.

A project capable of storing millions of tonnes of carbon dioxide

The scale of the Liverpool Bay carbon storage project is remarkable.

According to Liverpool Bay CCS Limited, the initial development is designed to store up to 4.5 million tonnes of carbon dioxide every year, with the potential to increase capacity to 10 million tonnes annually in the future.

The project is intended to support industries that produce significant carbon emissions, including manufacturing and other industrial operations across the North West.

Rather than releasing captured carbon dioxide into the atmosphere, the system will transport it offshore for injection into geological formations deep beneath the seabed.

In October 2026, the project reached another major milestone when the installation of the new Douglas carbon capture and storage platform was completed.

The purpose-built offshore installation will act as a central hub, receiving captured carbon dioxide and distributing it through pipelines towards the underground storage reservoirs.

The wider development is expected to support thousands of jobs during construction and hundreds of long-term positions.

Why can we see it from Formby and Ainsdale?

The offshore installations in Liverpool Bay are located sufficiently close to the Sefton coastline to be visible on clear days.

The ENSCO 120 is particularly noticeable because of its enormous height and distinctive lattice steel legs.

Depending on weather conditions and visibility, residents walking along the beaches at Formby, Ainsdale and Southport may be able to spot offshore structures on the horizon.

The rig can appear almost like a skyscraper standing in the middle of the Irish Sea.

And although it may look stationary, it is designed to be relocated when its work at a particular well has been completed.

A changing landscape off the Sefton coast

While most of us are familiar with the offshore wind turbines visible from our coastline, there is a great deal of other industrial activity taking place beyond the beaches.

Liverpool Bay is undergoing a significant transition from traditional offshore gas production towards infrastructure designed to support carbon capture and storage.

The enormous ENSCO 120 is one of the most striking examples of the offshore engineering activity taking place in these waters.

So, the next time you are enjoying a walk along Formby Beach and notice an unusual structure on the horizon, you may be looking at part of a much bigger story about the future of energy in the North West.

Have you spotted the enormous drilling rig from Formby, Ainsdale or Southport? Did you think it was connected to the offshore wind turbines?

We would love to hear your thoughts and see your photographs.

Photographs taken from Ainsdale Beach showing the ENSCO 120 offshore drilling rig in Liverpool Bay.