U.S. energy firm Equitrans Midstream has announced a delay in the completion of its Mountain Valley natural gas pipeline from West Virginia to Virginia due to adverse weather.

The project’s completion has been pushed back to the second quarter of 2024, citing adverse weather conditions in January.

The company also revised the estimated cost to complete the project to between $7.57 billion and $7.63 billion, up from the previous estimate of $7.2 billion.

"Construction crews encountered adverse weather conditions, including precipitation well above 20-year averages," said Equitrans CEO Diana Charletta in the company's fourth-quarter earnings release.

"These conditions were far worse and longer in duration than anticipated, imposing a significant impact on productivity."

The 303-mile Mountain Valley pipeline is the only major gas pipeline under construction in the U.S. Northeast. It has faced numerous legal challenges and regulatory hurdles since construction began in 2018, leading to multiple work stoppages.

The project, which is key to unlocking natural gas supplies from Appalachia, the nation's largest shale gas-producing region, required both a federal bill signed into law and intervention from the Supreme Court before construction could resume.

Despite the delays and cost increases, Equitrans reported better-than-expected earnings in its fourth quarter.

CEO Charletta also acknowledged ongoing discussions with third parties regarding potential strategic transactions, but cautioned that "there is no guarantee that any transaction will result from this process."

The Mountain Valley pipeline project is a joint venture led by Equitrans with a 49% interest, along with partners NextEra Energy, Consolidated Edison, AltaGas, and RGC Resources. Upon completion, Equitrans will operate the pipeline.