Louisiana pipeline blast leads to probe by federal regulators. LNG firm facing scrutiny.

Federal regulators have opened an investigation into the explosion of a nearly 50-year-old Gulf pipeline that has been out of service for 14 years and directed the owner to suspend operations, repair the damage and determine the fire’s cause along the southwest Louisiana coast earlier this month.

The pipeline owned by Delfin LNG blew open about 11:14 a.m. Feb. 3 in a natural gas explosion, creating a 50- to 80-foot-wide blaze with a blast crater near the shore in Cameron Parish, the federal regulators said in a new order.

The explosion launched about 5 feet of shattered pipe into the air and injured one worker.

The blast, which took hours to control, happened near Mae’s Beach and Johnson Bayou about 650 feet onshore and about half mile south of La. 82, the coastal highway in that part of the state, according to the Pipeline and Hazardous Materials Safety Agency.

“The release and ignition of natural gas poses a risk to public safety, people, and the environment,” PHMSA said in the order. “The proximity of the pipeline to a state highway, other hydrocarbon pipelines, and the Gulf of America increases the possible consequences of additional releases from the pipeline.”

PHMSA, which issued its order on Feb. 6, has preliminarily determined that the company’s pipeline inspection and cleaning work, which included injecting fresh natural gas into the closed line, triggered the fire.

Louisiana State Police and other local agencies are also investigating the blast.

Delfin LNG officials said they are cooperating with federal, state and local agencies and are “coordinating with PHMSA to ensure” the repair and assessment of the line are consistent with the agency’s requirements.

“We will continue forward on this project with the highest degrees of safety and integrity, and we will work with the agencies to implement any needed additional measures to ensure safe operations,” the officials said in a statement.

The worker injured in the blast has sued over his injuries, leveling several of the same allegations as contained in the PHMSA’s initial set of facts.

‘Public must be aware’

Delfin LNG bought the line from EnBridge in 2014 and has plans to use the 30-mile pipeline, which is primarily offshore, to send liquefied natural gas to a floating platform in the deepwater Gulf for foreign export. While Louisiana has become a hub of LNG exports with other large, onshore plants already operating, the Delfin LNG project and its offshore component would be unique.

Formerly known as the UTOS line, the 42-inch pipeline was built in 1978 originally to gather natural gas produced from platforms in the Gulf for onshore distribution in the United States. Delfin LNG wants to reverse the traditional flow, moving domestic gas produced on land offshore.

The Delfin project, which the Trump administration approved in early 2025, had been stalled for years amid questions from the Biden administration.

Since the approval, the project has faced criticism from environmental groups opposed to LNG export generally but which also question the safety of reusing the old line, the completeness of Delfin’s proposal and the risk it may pose to the Rice’s whale.

The Center for Biological Diversity sued in March last year to block the license from an arm of the U.S. Department of Transportation.

The group pointed out the same agency had denied the license less than a year earlier, in April 2024, and ordered an amended application to address design, operational and ownership changes since the project’s initial blessing in 2017. That case is on appeal.

Kenneth Clarkson, spokesman for the nonprofit, nonpartisan Pipeline Safety Trust, said the incident “highlights the risk of recommissioning old, unused or underutilized pipelines for new purposes, including transporting different products at different pressures, and often in different directions.”

Clarkson pointed out that PHMSA previously warned operators in 2014 about these types of projects and that Congress had mandated the agency in 2020 to develop regulations “to prescribe requirements to operators moving pipelines into and out of service.”

“Projects like Delfin’s are being proposed and constructed across the Gulf Coast region for liquefied natural gas, carbon dioxide, and hydrogen gas,” Clarkson added. “With more of this work on the horizon, operators, industry, regulators, and the public must be aware and protected from the inherent risks of repurposing pipelines transporting and storing these potentially dangerous products.”

Delfin officials said, however, that, in addition DOT’s approval, “the U.S. Coast Guard, 15 other federal agencies, the states of Texas and Louisiana, and several state agencies, fully reviewed and evaluated the proposed project, including the proposed reuse of existing pipeline infrastructure, and took public comment.”

Pinhole gas leaks

Before selling to Delfin LNG, EnBridge had shut off the pipeline, purged the gas and filled the line with inert nitrogen by late 2011. Delfin LNG officials said they recently began inspections “important to ensure that the line is in good working order.”

Delfin recently sent in equipment that runs inside of the pipeline, known as a ” pig,” to clean and inspect its condition, the PHMSA order says. After inserting gas back into the line, the pig hit a closed valve and sparked an explosion with the flammable natural gas, the PHMSA order says.

PHMSA said the fire released about 56 million cubic feet of natural gas.

Clarkson, the spokesman for the pipeline safety group, said the injection of gas “concerns us considering the pipeline has not been in operation for over a decade, and its integrity might be unknown.”

In the final years of Enbridge’s ownership, between 2010 to 2012, the line had at least seven pinhole gas leaks offshore from corrosion and three more from strikes by third-party vessels and equipment or company excavation work, PHMSA reports say. Clarkson said the strike by the dredging vessel in 2011 caused $8 million in damage and repair.

In the eight years before 2010, the same line had just one reported break when a fitting broke loose onshore in Cameron Parish amid heavy rain and flooding during Hurricane Rita’s landfall in 2005. The line was shut in at the time.

Asked if the increasing number of incidents in the final years contributed to the decision to close the pipeline, EnBridge officials said the company stopped using the line due to low utilization from offshore gas sources and demand.

The company said the pipeline had been maintained in accordance “with applicable regulations throughout Enbridge’s ownership.”

Delfin officials noted that in the years the pipeline remained closed and out of service while in their ownership, the company worked to ensure proper operation and maintenance, including through “regular reports to PHMSA.”