Allseas delivers 700-kilometer natural gas pipeline off Mexico

January 8, 2025, by Nadja Skopljak

Allseas has completed its offshore pipelay commitments for a 700-kilometer-long natural gas pipeline in Mexico ahead of schedule, for its client TC Energy.

The Southeast Gateway 36-inch natural gas pipeline runs south along the coast from Tuxpan through the Gulf of Mexico to Coatzacoalcos and Dos Bocas.

Allseas delivered the pipeline in 11 months, which included the complex nearshore scope and pre-commissioning of the entire system, under a contract secured in 2022.

Solitaire laid most of the pipeline, with Lorealay and Tog Mor providing first-class support. Pioneering Spirit installed the outstanding nearshore section at Coatzacoalcos, without a stinger. Instead, the hanging stinger transition frame served as a mini stinger, a solution tailored to the shallow water depth, Allseas reported.

Furthermore, the company deployed its automated ultrasonic testing system Dolphin for the work, inspecting more than 57,000 welds.

“The Southeast Gateway Pipeline Project, with much credit due to the performance of the collective Allseas/TC Energy team, is a classic example of how large scale offshore pipelay ventures are delivered safely, environmentally compliant, and on plan,” said Mike Bagale, TC Energy’s Vice President of Mexico Projects.

TCE is building the $4.5 billion deepwater gas pipeline in partnership with the Mexican state-owned power utility Comisión Federal de Electricidad (CFE) to secure the power supply in southeastern Mexico.

The Southeast Gateway Pipeline will transport around 37 million cubic meters of natural gas per day. It is planned to be in service by mid-2025.

Allseas recently completed the pipeline installation and post-lay activities for what is said to be a flagship project in the Dutch North Sea led by the Netherlands-based exploration and production player ONE-Dyas. Further off note, the company has bid farewell to a shallow-water pipelay barge it purchased in 1997, after having it used for installation of over 400 kilometers of nearshore pipeline across the world.