West Virginia Gas Pipeline Leak Sends US Futures Up 9% to Three-Month High

TC Energy’s Columbia Gas Transmission unit declared force majeure on its Mountaineer XPress Line 100 in western West Virginia on Thursday, after crews detected a mechanical leak near the Saunders Creek Regulator Station in Cabell County. The disruption has knocked out an estimated 1.8 million dekatherms a day of firm transportation service — roughly 1.8 billion cubic feet — and sent front-month Nymex natural gas futures up as much as 9.1% to their highest close in three months. As of Sunday, the company had not set a firm timeline for restoring full service.

A leak at a key regulator station

The company said the mechanical issue forced an immediate pressure reduction on Line 100 between the Mt. Olive Compressor Station in Jackson County and the Saunders Creek Regulator Station in Cabell County. Columbia Gas Transmission (TCO) said the problem was confined to the Saunders Creek site and that crews were on site working to fix it, without describing the nature of the mechanical fault or estimating a repair date. Mountaineer XPress is one of the larger-diameter pipelines built over the past decade to move Marcellus and Utica shale gas out of Appalachia, and Line 100 is a core segment of that system.

The biggest one-day jump since January

The scale of the reaction in futures markets reflects both the size of the outage and how tight the broader gas market had already become. The October Nymex contract settled up about 9.1% at $3.297 per million British thermal units on the day the outage was first reported, the largest single-day gain since January and an extension of a rally that has pushed prices up more than 25% since their April lows. Feedgas deliveries to the United States’ major LNG export terminals have also been climbing, averaging around 17.8 billion cubic feet a day in September, up from about 17.2 Bcf/d in August, adding another source of demand competing for the same Appalachian and Gulf Coast supply.

Why this pipeline carries weight beyond West Virginia

Columbia Gas Transmission’s network stretches roughly 11,900 miles across about ten states, including West Virginia, Ohio, Pennsylvania, Kentucky, Virginia, Maryland, New York, New Jersey, Delaware and North Carolina, moving Appalachian shale gas toward Mid-Atlantic and Northeast markets. A prolonged outage on a segment carrying close to 1.8 Bcf/d matters for utilities and industrial users well beyond the immediate area, particularly heading into the season when heating demand typically begins to firm up.

A supply story that reaches beyond the US

The West Virginia outage is unfolding against a backdrop of a global gas market that was already tightening. Front-month liquefied natural gas cargo prices for delivery into East Asia rose by $1.14 per million British thermal units over the past week to a weekly average of $10.73/MMBtu, even before the pipeline issue emerged, as buyers compete for cargoes heading into the northern hemisphere winter. On the domestic side, the broader rally in US energy prices this month has been reinforced by a U.S. Energy Information Administration outlook that still points to a relatively comfortable storage position — national inventories are projected at about 3,969 billion cubic feet by October 31, roughly 5% above the five-year average — which should limit how much a single pipeline outage can move winter price expectations on its own.

No firm restart date yet

TC Energy had indicated the restriction on Line 100 was likely to continue through at least the September 26–28 weekend period, with the next formal update expected on Sunday. Traders will be watching that update closely: any sign that the repair is taking longer than the weekend, or that TC Energy needs to keep the affected segment running at reduced pressure once it does return, would tend to keep a floor under the recent price gains rather than allow them to fully unwind. The episode also lands alongside a separate supply squeeze in European gas markets tied to Norwegian export cuts, underscoring how thin the margin for error has become across the Atlantic gas trade this autumn.

Sources

• Marcellus Drilling News, “WV Pipeline Leak Knocks 1.8 Bcf/d Offline, Gas Futures Jump 9.1%,” Sept. 25, 2026 — outage volume and futures move.
• The American Desk, “Mountaineer XPress Force Majeure to Continue Through Weekend After West Virginia Gas Leak,” Sept. 25, 2026 — timeline and TC Energy statements.
• BOE Report / EnergyNow.com — coverage of TC Energy/Columbia Gas Transmission force majeure notices and company statements on the Saunders Creek Regulator Station.
• Natural Gas Intelligence and Energy Intelligence market coverage — Nymex settlement levels and broader price context.

Illustrative image. Photo: Glen Dillon, CC BY 3.0, via Wikimedia Commons — source