The Energy Information Administration, the department's analytical division, said a series of refinery issues during the spring left crude oil processing at seasonal lows.
Crude oil runs, or the amount of oil processed at refineries, reached 16.1 million barrels per day for the week ending July 5, the highest rate for any week since 2007.
"While the increase in crude runs since March reflects a particularly strong rebound from spring maintenance, an underlying combination of recent refinery capacity expansions and relatively healthy margins helped drive the absolute level of runs to a multiyear high," the EIA said in a weekly report published Wednesday.
The EIA last week revised a report on refined products like gasoline, saying Midwest markets were not as vibrant as expected. The administration said it reported a decline in the amount of gasoline moving from refineries on the Gulf Coast from October 2012.
The EIA's latest report said Midwest crude oil runs were not at record levels, but were rebounding from early season declines, which were the lowest since late 2010.
EIA Administrator Adam Sieminski told lawmakers this week a series of logistical issues meant U.S. consumers were not yet feeling the full economic benefits of oil production gains.
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