FAIRBANKS -- Oil flowing through the trans-Alaska pipeline dropped by nearly 200,000 barrels a day in early May due to a combination of a slowdown in tanker traffic out of Valdez and limited storage at the terminal there, Alyeska Pipeline Service Co. said.
Pipeline operators restricted oil flow from the North Slope to keep the tanks in Valdez from becoming too full, an Alyeska spokeswoman said. Oil flow in the pipeline dropped from 550,000 barrels a day on May 1 to 355,000 barrels on May 9, according to state records.
The flow began increasing Sunday and had climbed to 463,000 barrels by Wednesday.
Alyeska spokeswoman Michelle Egan said one tank in Valdez is out of service for maintenance and there was a delay in tanker shipments, so the oil companies reduced the amount of oil placed into the pipeline.
"We prorated the producers for several days due to high inventory in Valdez and tanker schedules. The throughput levels will start to normalize over the next few days. However, we are going into summer season and maintenance season when we typically expect to see lower throughput," she said Wednesday.
The temporary slowdown will not have a major impact on the fiscal year totals for oil production, but it will add somewhat to the decline seen in production numbers compared to the previous year. So far this fiscal year, which began in July, oil production is down about 5 percent, compared to the fiscal year that ended last summer.
Average production in fiscal year 2014 was 531,000 barrels per day, while this year it has dropped to about 502,000 barrels a day.
Former Gov. Sean Parnell and many Republican legislators campaigned in 2014 on the premise that the Senate Bill 21 oil tax change had "stopped the drop" in Alaska oil production. The production level in fiscal year 2014 was about the same as in 2013.