At the end of July, Ukraine’s Danube port cluster sharply increased its intake of grain carriers amid a slowdown in operations at the Greater Odessa ports; however, a critical drop in water levels on the Danube could limit the capacity of this alternative export route.
According to the brokerage firm Spike Brokers, the number of grain railcars heading to the Danube ports increased nearly sevenfold over the week—from 167 to 1,141 thousand railcars. The average daily unloading rate rose by 17 railcars to 51 railcars per day.
At the same time, the number of grain railcars heading toward the ports of Greater Odessa fell by approximately 70%—to a record low of 1,356 railcars, compared to 4,525 railcars a week earlier. Average daily unloading decreased by 160 railcars to 690, while loading decreased by 203 railcars to 580 railcars per day.
In July, 1.38 million metric tons of grain were transported by rail to Ukrainian seaports, which is 37% less than in June. Additional constraints included overcrowding at certain port terminals and delays in transshipping grain from railcars to ships.
Thus, the increase in railcar deliveries to the Danube currently appears to be an immediate market response to the slowdown in operations in the Greater Odessa area. However, the capacity of the Danube route is also under pressure due to the rapid shallowing of the river.
At the end of July, the water flow in the Danube at the entrance to Romania dropped to 1,650 cubic meters per second, compared to an average July level of about 4,750 cubic meters. By August 4, according to forecasts, the figure could drop to 1,500 cubic meters per second, approaching the historic low of 1,400 cubic meters set in 1985.
Back in July, the Romanian Lower Danube Administration recorded a sharp drop in water levels across virtually the entire navigable stretch from Băziaș to Sulina. Near Corabia, several barges ran aground, and actual depths in certain critical sections decreased to 1.5–1.7 meters. Dredging operations are being carried out to maintain depths of at least 1.8–2 meters.
The main risk for Ukraine lies not necessarily in a complete shutdown of the Danube ports, but in a reduction in the permissible draft of vessels. Barges and river-sea hybrid vessels will be forced to carry less grain, which will increase the number of voyages, transportation costs, and fleet turnaround time.
Even if the terminals in Reni and Izmail retain the capacity to receive railcars, the slowdown in loading grain onto vessels could lead to a buildup of rolling stock at stations near the ports. The disparity is already evident: 1,141 railcars are heading toward the Danube ports, while the average daily unloading rate is only 51 railcars.
If this ratio persists, the terminals may once again face overcrowding, after which Ukrzaliznytsia will have to impose restrictions on the shipment of certain cargoes or implement temporary measures.
The second risk is related to the increase in queues on the Romanian sections of the Danube and the Sulina Canal. The ports of Reni and Izmail depend not only on the water depths directly at the Ukrainian berths but also on the condition of the entire Lower Danube route. As the Danube Commission notes, a single shallow section can become a “weak link” and restrict traffic along the entire international corridor.
Silting also complicates the transport of Ukrainian grain by barge to Constanta, Romania. A reduction in the load capacity of a single barge means that more vessels must be deployed to transport the same volume of cargo. This increases freight rates, transshipment costs, and the risk of fines for vessel downtime.
The third risk is the simultaneous decline in the reliability of the two main maritime routes. The ports of Greater Odessa are currently operating more slowly due to terminal congestion and delays in loading ships, while the Danube—which is supposed to serve as a backup route—faces a natural limitation on its throughput capacity.
This factor becomes particularly critical during the arrival of the new grain harvest. Rising logistics costs could lower purchase prices within Ukraine, delay the fulfillment of export contracts, and widen the price gap between Ukrainian ports and the global market.
On June 24, the Ukrainian Sea Ports Authority began operational dredging in the waters of the Port of Izmail. The work is intended to restore the design depths near the berths and allow for the maximum possible draft and cargo capacity of vessels. It was planned to be completed within two months.
However, dredging within the Ukrainian port alone cannot fully compensate for the drop in water levels in the Romanian and transboundary sections of the Danube. To maintain stable traffic flow, Ukraine and Romania will need to work in sync, promptly mark the fairway, conduct regular depth soundings, dredge critical sections, and regulate vessel queues.
The Ministry of Infrastructure had previously identified dredging as one of the main “bottlenecks” in Danube logistics and discussed with the European Commission and Romania the coordination of traffic, the use of the PRIMUS digital system, and measures to address a potential reduction in the capacity of the Odessa-Danube route.
The Danube ports remain a strategic reserve for Ukraine’s foreign trade.
After the start of the full-scale war, their throughput capacity was increased to 35 million metric tons per year. However, actual transshipment volumes fell from 17.4 million metric tons in 2024 to 8.9 million metric tons in 2025, and authorities had previously forecast approximately 5 million metric tons for 2026.
The current increase in grain ship traffic indicates that businesses are ready to quickly return to the Danube route should problems arise in the Greater Odessa area. However, record-low water levels in the river may prevent the ports from fully accommodating this additional traffic, potentially turning the rerouting of cargo by rail into a new logistical bottleneck.
