Drilled but uncompleted wells, or DUCs, are the topic that is the talk of the town, and just about everyone is watching, eagerly awaiting when their power will be unleashed and what the impact could be on oil and gas markets.

The U.S. Energy Information Administration (EIA) is now estimating the number of DUCs in seven of the country's most active shale plays. The estimates, which cover the prior month, are released alongside data in the Drilling Productivity Report.

Other sources already track the DUC tally in the U.S. But the EIA said methodology, operational assumptions and, in some cases, insufficient data, cause other sources’ estimates to vary significantly. The federal agency said it uses a consistent methodology and uniform assumptions for its report on DUC estimates.

Data released Sept. 14 by the EIA showed the oil-dominant Bakken, Eagle Ford, Niobrara and Permian regions had a combined 4,117 DUCs at the end of August, while the natural gas-dominant Haynesville, Marcellus and Utica regions had a combined 914.

The estimated DUC count for both oil and gas regions have been falling; however, the count in oil regions had increased in 2014 and 2015 before dropping by about 400 in the past five months, according to the EIA.

“Although both drilling and completion activity have declined since late 2014, completions have experienced a deeper decline than drilling in oil-dominant regions,” according to EIA. “The differences in drilling and completion rates in these oil regions may be attributed to several factors. For instance, some long-term contracts for drilling rigs and lease contracts may mandate drilling or producing in order to fulfill commitments made to the landowners and mineral-right owners.”

Lower commodity prices, which have hung around since the downturn began about two years ago, prompted many oil and gas companies to leave wells uncompleted.

Oil prices have rebounded since hitting lows around $27 per barrel (bbl) earlier this year; however, prices have failed to surpass $50/bbl. Brent crude futures were trading at $46.18/bbl the morning of Sept. 15 as West Texas Intermediate futures traded at $43.80/bbl.

The world’s abundant supply of hydrocarbons remains, although U.S. crude inventories dropped by 559 Mbbl during the week ended Sept. 9. A Reuters report stated that analysts were expecting a crude build of 3.8 MMbbl.

“A high inventory of DUCs has implications for the size and timing of the domestic supply response to changes in oil prices, with or without significant changes in the number of active drilling rigs,” the EIA said.

Velda Addison can be reached at vaddison@hartenergy.com.