The US Strategic Petroleum Reserve (SPR) remained steady last week but could see renewed withdrawals after the Trump administration announced plans to sell up to 4 million barrels of crude oil in response to Hurricane Isaias, on top of ongoing sales related to disruptions in the Middle East

Energy reserves could also become a more potent political issue, with a top Democrat inquiring about the “structural integrity” of the depleted caverns following steep drawdowns since the start of the Iran War.

The new data released on Tuesday by the US Department of Energy showed the energy backstop remaining at 283 million barrels as of Oct. 9, matching the level seen a week prior.

The latest reading is the lowest since October of 1982 and about 13 million barrels away from the first reading on record, from August of that year, as the backstop was coming online under President Reagan.

FREEPORT, TEXAS - OCTOBER 19: In an aerial view, the Strategic Petroleum Reserve storage at the Bryan Mound site is seen on October 19, 2022 in Freeport, Texas. US President Joe Biden is planning to release fifteen million barrels of oil from the nation's emergency reserves in an effort to continue curving gas prices around the country. The deal completes Biden's March initiative to release 180 million barrels from the Strategic Petroleum Reserve.  (Photo by Brandon Bell/Getty Images) The Strategic Petroleum Reserve storage at the Bryan Mound site is seen in 2022 in Freeport, Texas. (Brandon Bell/Getty Images) · Brandon Bell via Getty Images

SPR withdrawals in response to hurricanes are regular occurrences. Hurricane Isaias left four people dead and more than 650,000 without power after making landfall in Florida last week.

The announcement on Saturday indicated plans to sell 4 million barrels of crude oil “to address supply disruptions due to inclement weather in the Gulf of America,” the Trump administration’s preferred name for the Gulf of Mexico.

The transaction would be an exchange, with the government asking companies to return the crude oil “with additional premium barrels” in 2027.

But the move will further deplete the reserve in the immediate term and comes alongside a parallel Trump administration effort to complete withdrawals promised earlier this year to bolster energy markets upended by the war in Iran.

The Department of Energy recently announced a request for bids to sell 40 million barrels in the coming months as part of that effort.

Low reserve levels could draw increased political scrutiny next year if Democrats regain power.

“I am deeply concerned by reports that recent drawdowns of the SPR could damage the salt caverns that hold millions of barrels of America’s emergency crude,” wrote Senator Martin Heinrich of New Mexico in a new letter released Tuesday.

The Trump administration has said for weeks that only 70 million barrels must remain in the reserve to safely manage the caverns, an assessment that has been questioned by some experts, including a prominent former Biden energy official.

Heinrich added that the Energy Department had failed to substantively respond to previous queries and said he would soon introduce legislation to mandate long-term planning for the SPR.

WASHINGTON, DC - MARCH 17: U.S. Sen. Martin Heinrich (D-NM) speaks to reporters after a roundtable on rising energy costs on Capitol Hill on March 17, 2026 in Washington, DC. Senate Democrats held the hearing to discuss the rise of energy prices for people in the United States. (Photo by Anna Moneymaker/Getty Images) Sen. Martin Heinrich is seen after a roundtable on rising energy costs on Capitol Hill on March 17. (Anna Moneymaker/Getty Images) · Anna Moneymaker via Getty Images

The New Mexico lawmaker is ranking member of the Senate’s Energy Committee, meaning he would be in line to chair that powerful committee if Democrats take control of the upper chamber after the midterm elections.

The US reserve currently sits at about two weeks of US oil consumption amid widespread worries about global stockpiles and as the Trump administration continues to wrestle with elevated prices for both gasoline and diesel.

For his part, Trump has continued to project confidence that US reserves will be quickly refilled. He told a crowd in Alabama recently that, because of an energy deal with Venezuela, “we’re going to be filling up very shortly our strategic reserves for nothing.” 

Despite Trump’s promises, experts say refilling the reserves will be a complex and far-from-free process that could take years.

Ben Werschkul is a Washington correspondent for Yahoo Finance.

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