U.S. strategic reserves are getting so low the drawdown threatens to damage the 60 underground salt caverns storing American oil

Strategic oil inventories have reached a 40-year low, and experts warn their continued depletion could damage the underground caverns where the reserves are stored.

Last week, the Strategic Petroleum Reserve (SPR) plunged below 300 million barrels for the first time since the 1980s, when the reserves were being filled, according to the Department of Energy. That pool is expected to drain further to 243 million barrels as the U.S. releases 172 million barrels to manage severe supply disruptions and rising energy costs due to the Iran war.

Those reserves are kept in 60 salt caverns across two sites in Texas and two sites in Louisiana, each thousands of feet underground. They have a total storage capacity of 714 million barrels. But as oil is drained from these reserves, the integrity of the caverns may be imperiled.

“I don’t know anyone who believes we can go below 300,” Amos Hochstein, a senior energy advisor for former President Joe Biden, told CNBC on Saturday. “I know plenty of people who think we can’t get near 300 because physically you will damage the ...