Ukrainian grain exports through the Black Sea are facing new logistical strain as record-low water levels on the Danube River complicate shipments through Romania, Bloomberg reported. The bottleneck comes just as Russian strikes force Ukraine to reroute part of its grain cargoes away from Odesa and other ports.
Since Russia's full-scale invasion in 2022, the Romanian port of Constanta has become a key alternative route for Ukrainian grain reaching world markets. Cargo typically arrives at the port by rail, truck and Danube barge, but heat and a lack of rainfall have driven down the river's water level, forcing ships to carry smaller loads.
Smaller loads raise the cost of river transport and add extra costs and delays for road and rail logistics, at the exact moment the Black Sea export corridor needs more alternatives, not fewer.
Constanta's capacity limits
Viorel Panait, president of the Constanta Port Business Association and chief executive of grain terminal operator Comvex, said his terminal could handle 20% more cargo under the EU-Ukraine Solidarity Lanes project. He said the Danube supplies cargo to the terminal, and that the shortage of water is affecting how much grain arrives.
The Solidarity Lanes were set up by the European Commission in May 2022 as alternative rail, road and water routes for Ukrainian exports and imports after sea ports were blockaded. They lost much of their critical importance in 2023 once ports in the Greater Odesa area resumed operations.
Ukraine is also negotiating with neighboring countries to open new export routes. But rail transport combined with the Danube route can supply only a third of the capacity of Ukraine's Black Sea ports.
Prices and mounting pressure
The situation is worsening amid high energy prices and disruptions to global trade linked to tensions in the Middle East. Wheat and corn futures jumped sharply on the Paris and Chicago exchanges last month.
Burak Cetinok, global head of research at brokerage Arrow, said that without immediate relief, whether from an easing of fighting in the Black Sea or a recovery in Danube water levels, prices could stay elevated.
According to Bloomberg, the logistical strain could intensify in the coming months, since Romania expects a record harvest of wheat, barley and rapeseed. Mild temperatures are delaying the corn harvest in the country's main growing regions, meaning corn shipments could overlap with the end of the wheat export season, competing for the same trucks, rail capacity and river barges.
Adrian Dobrita, head of trading at RWA Raiffeisen Agro Romania, said Constanta's role since 2022 has been to act as a safety valve, taking cargo west through Romania when Odesa comes under attack. He said that arrangement assumes the corridor feeding Constanta has spare capacity, and it does not.
Attacks on Ukrainian ports
In July, Russia attacked ships in Ukrainian ports 35 times and at sea 22 times, and struck port infrastructure 67 times, compared with 14 attacks on ships recorded in all of 2025. Shipowners have suspended calls to ports in the Odesa region as harvest season picks up in Ukraine.
The All-Ukrainian Agrarian Council has warned that the current port blockade could hit the economy harder than in 2022.
The Ukrainian Grain Association forecast on July 30 that a good harvest could push exports of grain and oilseed crops to nearly 52 million tonnes in the 2026/2027 season, up from 41.1 million tonnes last season. That outlook depends on resolving Ukraine's logistics problems, particularly the full restoration of the deep-water ports of Greater Odesa. Because of the port stoppages, Ukraine has already cut its grain export forecast by 12% for the July 2026 to June 2027 season compared with its previous projection.
