Associated Press

CAMARILLO, Calif. — Gasoline prices around the country jumped to record highs during the past two weeks as the nation’s epic blackout temporarily shut down some refineries and a broken pipeline caused shortages in Arizona.

The shortages pushed average retail gasoline prices up more than 15 cents a gallon nationally, the biggest two-week hike since the Lundberg Survey began keeping records 50 years ago.

The survey of 8,000 service stations on Friday showed an average of all grades of gasoline reached $1.7484 a gallon, just short of the survey’s all-time high weighted average of $1.7608 set last March 21, analyst Trilby Lundberg said Sunday.

The refinery shutdowns, caused by the blackout in parts of the Northeast and Midwest, combined with the break in a major pipeline in Arizona to disrupt supplies, Lundberg said.

The reopening of the pipeline Sunday and the end of the blackout means gas prices should fall, she said. The customary September decline in demand and an influx of imported gasoline also should stabilize prices.

Self-serve regular gasoline showed an average weighted price of $1.7191 a gallon, with mid-grade at $1.8127 and premium grade at $1.9046.

Phoenix had the highest leap in the nation during the two-week period, with prices jumping 60.42 cents a gallon for self-serve regular. On Aug. 22, self-serve regular averaged $2.1425, the highest price in the nation for that grade.

The lowest price for that grade was $1.4920 in Charleston, S.C.

The trouble in Phoenix started when the pipeline ruptured July 30 because of corrosion. The line, which delivers gas from El Paso, Texas, was reopened Aug. 1 but shut down again on Aug. 8 after safety concerns surfaced.

The shortage came to a head last weekend when gas stations began running dry. At its worst, two-thirds of metro gas stations were empty and some that remained open sold a gallon of gas for $3.99 and higher.

The pipeline went back into operation Sunday. Eighty-five percent of the Phoenix area’s 700 or so stations had gas on Sunday, according to state officials, but prices remained high.