The US naval blockade is having significant impact on oil flows in Iran, which is running out of places to store its own crude and only about 22 days of capacity left to avoid a crippling production shutdown.
With shipments falling sharply and fuel reservoirs nearly filled, Iran’s storage capacity crisis poses a prominent threat to the country's infrastructure.
Analysts say the country could soon run out of space to store oil — forcing deeper production cuts and potentially triggering long-term damage to its energy system.
According to data firm Kpler, The Wall Street Journal and Bloomberg, the blockade has cut exports by roughly 70%, forcing Iran to revive derelict sites known as “junk storage,” using improvised containers and trying to ship crude by rail to China.
The unusual steps are aimed at delaying an infrastructure crisis and blunting Washington’s leverage in the standoff over the Strait of Hormuz, according to The Wall Street Journal.
Since early April, with the imposition of the naval blockade on Iranian ports, the volume of oil loading onto tankers has dropped from 1.85 million barrels per day in March to only 567 thousand, according to a Bloomberg report.
And despite reports saying some tankers have evaded the blockade, data from Kpler and The Wall Street Journal said no ships have successfully escaped the US blockade of Iranian ports, with officials stating that vessels had been turned back or complied with redirection orders.
Chabahar Port, located east of the Strait of Hormuz and outside the Arabian Gulf, is a critical backup gateway for Iran to circumvent strait-related risks. However, satellite imagery confirms that around six to eight Very Large Crude Carriers (VLCCs) are anchored off the coast of Chabahar in the Gulf of Oman, where the tankers serve as “floating oil storage” unable to break the US blockade.
To manage the crisis, Iran is using new ways to store excess oil that it cannot sell due to the blockade. Tehran has activated the 30-year-old supertanker Nasha for emergency oil storage near Kharg Island.
According to Kpler, the accumulation of oil at sea is substantial. Iran currently holds around 184 million barrels of crude in floating storage, with 60 million barrels trapped within the blockade zone and the remainder located near major Asian trading hubs.
Last week, the US Navy said it forcefully intercepted and turned away two VLCCs.
Iran's onshore crude inventories have risen by about 4.6 million barrels since the blockade to nearly 49 million barrels, according to Bloomberg.
While total storage capacity is estimated at around 95 million barrels if additional northern refinery tanks are included, Kpler said operational constraints, safety limits, and geographic factors mean a significant portion of this capacity may not be practically usable.
This means that Iran has just 12 days of onshore capacity storage left, rising to about 22 days including floating storage, before it is forced to cut production of up to 1.5 million barrels a day as soon as mid-May.