Pipeline Construction Supports Reliable Energy Delivery to Global Markets

Near the Gulf, Sempra Infrastructure is investing in a next-generation liquefied natural gas (LNG) facility to deliver reliable energy to global markets. The Port Arthur Pipeline Louisiana Connector (PAPLC) Project — a 72-mile, 42-inch-diameter pipeline with 18 trenchless crossings totaling over 57,000 feet — will be a key supplier for the Port Arthur LNG facility, transporting natural gas from south Louisiana for liquefaction and export. 

Our multidisciplinary team partnered with Sempra Infrastructure on the PAPLC project, providing trenchless detailed design, geotechnical engineering, permitting support, and construction monitoring and consulting. 

Providing Creative Solutions for Pipeline Construction 

The pipeline route crosses waterways, highways and private property, requiring creative trenchless solutions. Our team designed 13 water crossings and five major road crossings, including Interstate 10, a major highway in the Southern U.S., using horizontal directional drilling (HDD) and Direct Pipe® (also known as Direct Steerable Pipe Thrusting or DSPT) methods. The project’s longest HDD spans 6,874 feet. 

At the Kim Street installation in Louisiana — the project’s only DSPT crossing — the team made use of limited space. Originally permitted for open-cut construction, our design team reconfigured the DSPT crossing and pipe stringing to fit within the smaller-than-normal area to accommodate a local business. 

Instead of staging one continuous pipe string behind the launch pit, the team positioned seven shorter sections to the side. The construction crew used additional equipment to manage these heavy sections, including cranes and excavators, to lift and reposition each section for welding before tunneling it into place.

Our creative crossings solutions have helped the project stay ahead of schedule and under budget. 

Leading Data-Driven Design and Regulatory Success

A detailed investigation was critical for evaluating trenchless feasibility and providing the necessary documentation to permitting agencies to approve trenchless construction methods. We conducted extensive subsurface geotechnical investigation, including 72 borings, some of which were required to support route modifications that reduced environmental impacts by more than 10 acres and helped secure FERC approval.

Delivering Ahead of Schedule

Trenchless crossing construction was completed in six months and ahead of schedule, despite challenging terrain, marine environments and weather-related delays. Our on-site monitoring and real-time recommendations helped minimize risks and keep the project on track. All trenchless crossings met stringent Class III requirements for the 42-inch-diameter pipeline, designed to operate at 1,440 pounds per square inch and supply 2 billion cubic feet of natural gas per day.

The PAPLC project strengthens U.S. energy infrastructure, supports thousands of jobs and provides access to reliable natural gas delivery to global markets. By finishing ahead of schedule and under budget, the project set new benchmarks for responsible infrastructure development.