Pennsylvania data showed drillers in the state produced 18% more natural gas in August than they did in the same month in 2017, but it also showed slow, single-digit production growth for all of 2018.

Production grew 1.7% between July and August of this year, according to data from the Department of Environmental Protection released Oct. 15. Production grew less than 5% year-to-date.

Until this summer, Marcellus Shale drillers had little motivation to produce more gas. Gas prices stayed stuck below $3/MMBtu on the national market and were about half that in local markets, where surplus gas was dumped because of a lack of pipeline capacity.

But with Energy Transfer Partners LP's new Rover Pipeline LLC system in Ohio pulling gas off legacy lines in southwest Pennsylvania and Williams Cos. Inc.'s new Atlantic Sunrise pipeline expansion providing takeaway in the northeast quarter, the state's largest producers are cranking up production to fill the empty space.

What did not change in a year was the hammerlock that five counties have on the state's total production: 74% of Pennsylvania's shale gas comes from Susquehanna, Bradford and Lycoming counties in the northeast part of the state and Washington and Greene counties in the southwest. Susquehanna, Bradford, Lycoming and Wyoming counties produce more shale gas than all of Ohio. Susquehanna County alone produced just over 4 Bcf/d in August. The state's top five producers accounted for 66% of the state's total gas production.

EQT Corp., the nation's largest gas producer by volume and the dominant driller in Greene and Washington counties south of Pittsburgh, increased production 7% in August compared to July. Northeast Pennsylvania giant, Cabot Oil & Gas Corp., with contracts for 1 Bcf/d of Atlantic Sunrise's 1.7 Bcf/d of incremental gas transportation capacity, increased production 10% in August ahead of a hoped-for September pipeline opening.

Heavy rains delayed Atlantic Sunrise's opening until Oct. 6. Gas volumes immediately spiked when Williams opened the valves on Oct. 6. Atlantic Sunrise moves Marcellus gas out of Susquehanna and other northeast Pennsylvania counties to mid-Atlantic markets and deep into the Southeast along the Transcontinental Gas Pipe Line Co. LLC mainline. The system brings gas to the Washington, D.C., metro area and Dominion Energy Inc.'s Cove Point LNG LP natural gas export terminal in Maryland.

The state's three other leading gas producers saw their production volumes fall slightly in August when compared to July. On a year-over-year basis, both Range Resources Corp. and Southwestern Energy Co. continue to book 20%-plus volume growth, but compared to July gas production at both slipped. Both firms have said they are increasing the amount of NGLs, such as ethane and propane, they are extracting from the gas production of their southwestern Pennsylvania wells at higher oil-linked prices, an effort that slightly reduces gas volumes.

Chesapeake Energy Corp. has made it clear that its corporate future is in shale oil in the state of Wyoming's Powder River Basin, and it intends to milk northeast Pennsylvania for cash to drill wells in the hot new play. Several of Chesapeake's Appalachian rigs are still in the Utica Shale in Ohio, finishing work on leases that are being sold to private equity-backed start-up Encino Acquisition Partners LLC. Chesapeake's production in northeast Pennsylvania's Marcellus Shale slipped nearly 4% in August compared to July.

"We have rigs staying in Ohio through the closing of the transaction, and then they'll stay there," Chesapeake CFO and Executive Vice President Dominic Dell'Osso said on the company's second-quarter earnings call Aug. 1. "Post the closing of the transaction, we'll operate them under our transition services agreement. But as soon as the transaction closes, the CapEx moves off of our books and onto the buyer."

The Chesapeake-Encino deal is expected to close in the fourth quarter.