The Panama Canal Is Quietly Getting Shallower. El Niño Has Not Even Arrived Yet.

Most supply chain teams tracking maritime chokepoints have focused on the Strait of Hormuz since March. The Panama Canal is now adding itself to that list, and unlike the Iran war, this disruption has a weather forecast attached to it.

The Panama Canal Authority announced it will step down the maximum draft for the largest vessels transiting the Neopanamax locks in two stages. The draft, which stood at the normal 50 feet this spring, will fall to 49 feet on July 24 and then to 48.5 feet on August 15. The authority describes the steps as part of a proactive water management strategy, closely monitoring water levels in Gatun Lake, which is the primary reservoir for the entire canal's operations.

The trigger is El Niño. Forecasters expect one of the most severe El Niño events in recent years, with reduced rainfall threatening the freshwater levels that the canal depends on to operate. The authority acted early precisely because the 2022 to 2023 drought demonstrated what happens when it waits. During that episode, repeated emergency restrictions eventually drove the draft down to the 43 to 44 foot range, with a low of 38.5 feet, and the resulting backlog sent transit slot auction prices to record highs while large gas carriers diverted around South America and containerships offloaded boxes for transshipment across the Isthmus.

Where things stand right now and what the curve looks like

The current restrictions are not yet severe. The online dashboard shows operations running smoothly, with 10 ships without reservations waiting and 65 ships with booked slots standing by off the canal's terminuses. Waiting time for non-booked vessels is currently 4 days northbound, down from a peak of 11.5 days last month, and 1.8 days southbound, down from a peak of 15 days in June.

That June peak is worth dwelling on. Waiting times hit 15 days southbound just last month, well before the draft restrictions have even reached their first scheduled step down. Volume at the canal surged this year after the closure of the Strait of Hormuz and the disruptions in the region, with reports of record prices being paid at the auction of available transit slots. The canal is absorbing diverted traffic from one geopolitical crisis while simultaneously bracing for a climate-driven one.

The compounding pressure from diverted Hormuz traffic

The timing could not be more difficult. Traffic that previously moved through the Strait of Hormuz has been rerouting since March, with much of it adding to Panama Canal demand as shippers seek alternative routes to connect Asian production with Western markets. A canal already handling elevated throughput from Hormuz diversion is now being asked to do so with progressively less water under the hull of its largest vessels.

Draft restrictions directly translate to cargo capacity limits. A vessel that normally loads to a 50-foot draft must lighten its cargo to transit at 48.5 feet, either by carrying fewer containers or reducing the weight of loaded boxes. For bulk carriers and tankers, the calculation is even more direct: less draft means less cargo per voyage, more voyages needed to move the same volume, and higher per-unit freight costs for whoever is buying the goods at the other end.

The 2022 to 2023 precedent and why it matters

The prior drought episode is the relevant benchmark. It began with modest, precautionary draft reductions and ended with emergency restrictions at 38.5 feet, growing backlogs, and transit slots selling at prices that rewrote the economics of Panama Canal routing for an extended period. Shippers that had built supply chain economics around Panama Canal transits found themselves choosing between waiting in line, paying auction premiums, or diverting around Cape Horn.

The authority's early action this time is intended to avoid the most acute phase of that sequence, giving the market time to adjust gradually rather than scrambling for solutions under emergency restrictions. Whether El Niño arrives at the severity forecasters expect will determine how far down this path the draft restrictions travel. The scheduled July and August reductions are not the floor. They are the beginning of a managed descent whose endpoint depends on rainfall the canal cannot control.

The exposure for European and Asian companies

Any company routing goods between Asia and the US East or Gulf Coast, or between South America and Asia, through the Panama Canal is now operating in a corridor where capacity per vessel is declining on a published schedule and where the downside scenario, a return to 2022 to 2023 conditions while Hormuz diversion traffic simultaneously inflates demand, has no comfortable resolution date attached to it.

The disruption does not arrive as a port closure or a force majeure. It arrives as a half-foot reduction in maximum draft, published weeks in advance, on a timetable that makes the direction of travel clear without guaranteeing where it stops.