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Barrow gas field keeps powering Utqiaġvik
Producers Magazine Preview: Decades old project remains a unique story for North Slope natural gas first found in 1940s
Eric Lidji for Petroleum News
It’s a uniquely Alaska anomaly.
While the wider North Slope region has been trying for years to monetize its extensive natural gas resources for decades, one small community has been benefitting for years.
Under the operatorship of the North Slope Borough, the Barrow gas fields have been the foundation of affordable and relatively secure energy for the city of Utqiaġvik for years.
The program subverts the usual paradigm for Alaska. Remoteness is usually a leading factor preventing development of known resources. But Utqiaġvik’s remoteness has made it nearly impossible to develop the nearby gas fields for anything but local use.
The Barrow gas fields emerged from federally sponsored exploration in the National Petroleum Reserve-Alaska after World War II to improve domestic energy security.
Federal contractors discovered the fields on separate expeditions between the late 1940s and the 1980s. The fields have generally required minimal development work, aside from a $92 million rejuvenation program launched in 2011 to combat declining production.
With that effort, the city commissioned the Savik 1 and 2 wells at the East Barrow field and the Walakpa 11, 12 and 13 wells at the Walakpa field. By improving deliverability, the city of Utqiaġvik can now rely on natural gas for its energy needs even during cold snaps or during maintenance activities, instead of switching to diesel as an alternative.
South Barrow The U.S. Navy discovered the South Barrow field with the 2,505-foot South Barrow No. 2 well in 1948, during its initial wave of NPR-A exploration following World War II.
Production began the following year. Drilling continued through 1987 with 13 new wells drilled and one existing well - South Barrow No. 7 - deepened, according to the AOGCC. Production began in November 1981 at 3.5 million cubic feet per day.
The South Barrow field produced consistently from 1950 through 1990, at which point operators began to suspend production sporadically. The field was shut-in with increasing regularly through the 2000s, often being used only to increase supplies in winter.
After nearly six years of inconsistent production, South Barrow has now been producing regularly since May 2018. The field produced 99.3 million cubic feet in 2021, up considerably from 56.1 million cubic feet in 2021, according to the AOGCC.
The South Barrow field is producing from three wells: S. Barrow Test Well No. 6, South Barrow NSB No. 1 and South Barrow No. 9. The field produced exclusively from S. Barrow Test Well No. 6 from January 2020 through July 2020, when it went offline. It was back online from April 2021 through June 2021 and again in November and December 2021. South Barrow NSB No. 1 came online in February 2021 and went offline in June 2021, which accounted for increased production in 2021. It returned from December 2021 through March 2022. South Barrow No. 9 produced in July 2021.
Cumulative production at South Barrow passed 24 billion cubic feet by June 2022, according to the AOGCC. Early forecasts estimated some 32 billion cubic feet in lifetime production at the field, suggesting the potential of ongoing production for years to come.
East Barrow The U.S. Geological Survey discovered the East Barrow field with the South Barrow No. 12 well in 1974, during the second wave of oil and gas exploration in the NPR-A.
Production began in December 1981. Drilling continued through 1990, with eight wells total. The North Slope Borough more recently returned with the Savik drilling program.
Gas production peaked in early 1983 at some 2.75 million cubic feet per day.
The East Barrow field produced nearly 47 million cubic feet from the South Barrow No. 14 and Savik No. 1 wells in 2021, down considerably from 139.1 million cubic feet in 2020 according to the AOGCC. The decline started in spring 2021 and culminated in a shutdown of production through the latter half of the year before resuming in December.
Production was restored somewhat this year. The field produced nearly 60 million cubic feet through the first half of the year, down somewhat from 2020 but well above 2021.
Cumulative production through June 2022 was nearly 9.9 billion cubic feet, well above the 6.2 billion cubic feet in place originally estimated for the East Barrow field. The city of Utqiaġvik attributes the productivity to the presence of methane hydrates at the field.
Walakpa Working under a U.S. Navy contract, Husky Oil discovered the Walakpa field with the 3,666-foot Walakpa No. 1 well in the 1980s. Production began in the late 1992. The field has peaked above 5 million cubic feet per day numerous times in the decades since.
Walakpa is the most productive of the three Barrow gas fields, currently producing from 11 wells - Walakpa No. 3 through Walakpa No. 13. The field produced 1.4 billion cubic feet in 2021, up from 1.3 billion cubic feet in 2020, according to the AOGCC. The field produced 746 million cubic feet in the first half of 2022, on pace with 2021 rates.
Cumulative production through June 30, 2022, was 37.3 billion cubic feet.
The South Barrow and East Barrow reservoirs have a stratigraphic setting similar to the Alpine oil field. Walakpa is in the Pebble Shale unit, a major North Slope source rock.
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