Alaskan oil production in November fell 9.5 percent from a year earlier because of maintenance in fields operated by BP Plc, including Prudhoe Bay, Kuparuk, Endicott and Lisburne.
Production averaged 641,544 barrels a day last month, down from 709,263 in November 2009, according to the Alaska Tax Division. Output decreased 1.9 percent from October 2010.
Production dropped briefly in mid-November because of “some field maintenance issues,” Steve Rinehart, a spokesman for BP, said in a telephone interview. “It was nothing major and resolved in three or four days.”
The last time output in Alaska posted a year-on-year gain was in 2002, state records show.
Alaska’s daily stockpiles of crude averaged 4.45 million barrels in November, down from 5.27 million a year earlier and higher than the 4.35 million in October, the tax division said.
Production from oil fields in Alaska operated by BP drops during maintenance periods, which usually occur in July and August as operators take advantage of warmer weather.
Crude from Alaskan fields is carried by the 800-mile (1,300-kilometer) Trans Alaska Pipeline System, which runs from Prudhoe Bay to Valdez, the northernmost ice-free port in the U.S.