The Sur de Texas-Tuxpan gas pipeline is an offshore natural gas pipeline between Brownsville, Texas, and Veracruz, Mexico. The $3.1 billion project is being developed by the Federal Electricity Commission (CFE) of Mexico, and is the country’s first subsea pipeline.
The underwater pipeline has been touted as one of the longest pipelines ever constructed by TransCanada in Mexico and will have a total length of 800 km and a diameter of 42 in. It will include both onshore and offshore routes, with the offshore portion being the longest.
A joint venture between TC Energy (formerly TransCanada) (60 percent) and Sempra Energy’s Mexican unit IEnova (40 percent) (known as Infraestructura Marina del Golfo or IMG) is constructing the project. The JV won a 25-year build-own-operate (BOO) contract from CFE in 2015. Construction of the nearly 500-mile long pipeline, mostly under the Gulf of Mexico, commenced in the port of Altamira, Mexico, in May 2017.
The pipeline will transport up to 2.6 billion cubic feet of natural gas a day, and will interconnect with a number of other proposed pipelines, including Nueces-Brownsville gas pipeline and Tuxpan-Tula gas pipeline. The pipeline is also expected to link with an existing network in Cenagas’s pipeline system in Altamira, as well as others in the region.
Altamira port will serve as the production and logistics center for the project, which will primarily transport gas to power plants operated by CFE in the Mexican states of Tamaulipas and Veracruz, as well as to various plants in the eastern, central and western regions of the country.
It will also supply natural gas to several power generation plants that are scheduled for construction, as well as existing facilities currently operating on fuel oil, which will be converted into natural gas-powered plants.
Why Project is Outstanding:
The project has two Landfalls , one in Altamira (Tamaulipas) and other in Tamiagua (Veracruz) , the first was made by a microtunnel and the second with a Direct Pipe, both trenchless methods used to avoid damage to the coastal environment in both locations populated by mangrove forests and a very rich fauna and flora characteristic of these ecosystems.
In particular, the Altamira Landfall represented a challenge of engineering, logistics and construction out of the ordinary. The landfall is located in a flood zone without access, with a maximum historical flood level of +2 m, consequently, an access road 6 km long and a work platform 980 m long by 120 m wide had to be built.
Last year TERRATEST put the finishing touches on a world-record microtunnel under the Gulf of Mexico from the port city of Altamira. The Altamira Landfall, a key component of the Sur de Texas-Tuxpan project, included the record-setting 7,360-ft microtunneling drive of 10.5-ft OD pipe with an underwater recovery of the MTBM. The drive also involved two vertical curves.
Upon the completion of shaft construction in October 2017, the MTBM was commissioned in November 2017, and completed its drive on July 27, 2018. On June 11, 2019 the Consortium in charge of the Construction of the Project officially announced having obtained the mechanical completion.
Crews used a Herrenknecht AVND2000 with Push-Module extension kit to achieve the historic drive. The Push-Module includes a rotary ring erector to install precast segments as a contingency method. Crews recorded a best daily performance of 25.5 m, and a best weekly performance of 111.2 m.
Many challenging aspects of the $55 million USD tunneling project were successfully overcome, such as tunnel completion having a very low skin friction (0.4kN/m2) and an average jacking force of (0.65 T/m); the bundle was effectively installed inside the tunnel (which involved two42-in. gas transmission pipelines and one 24-in. water line); and both the TBM and Push-Module were successfully recovered from the seabed.
Project Owner: Comision Federal Energia (CFE)
Engineer: Eurohinca for Microtunnel and Intecsea for Bundle Installation
Contractor: Terratest/Eurohinca for Microtunnel and Civil Constructions , GDI -Sicim Pipelines SA DE CV (onshore) and Allsea (offshore) for Bundle Installation
Value of Trenchless Project (US$): $55 million