Iran War Drains US Oil Stockpile to 40-Year Low, Threatening Cavern Stability

The US emergency oil stockpile has dropped to its lowest level in 40 years, sparking concerns over the structural integrity of its underground salt caverns. The current drawdown for the war with Iran is putting a heavy strain on the Strategic Petroleum Reserve, which now stands at 243 million barrels. This is a significant decrease from its peak capacity and raises worries about the long-term viability of the reserve.

Petroleum engineering professor Siddharth Misra of Texas A&M University warned that repeated rapid drawdowns can cause salt walls to erode, creating flatter roofs and thinning critical salt pillars. This process increases the risk of a structural cave-in. The practical operational floor for the crude inventory is between 250 million and 300 million barrels, below which the system loses its ability to pump oil at high speeds.

The reserve was designed to handle five full drawdowns over its lifespan but has undergone dozens of cycles in just 40 years. Misra noted that this excessive use has caused severe cavern deformation and accelerated salt falls from the ceilings. The Department of Energy rejected claims that the facilities were at risk, insisting that the caverns are being responsibly managed as a critical national security asset.

The ongoing withdrawals have also contributed to unprecedented gas prices for late summer, with today's AAA National Average for a gallon of regular gasoline sitting at $4.07, marking the highest levels on record for mid-August.