Romania to sink four barges in the Danube to boost water flow to Cernavodă nuclear power plant

Romanian authorities plan to sink four barges in the Danube on Wednesday (5 August 2026) to redirect more water toward the Cernavodă Nuclear Power Plant amid critically low river levels.

Specialists reported that after the displacement of the Pârjoaia rock formation, the water level near Cernavodă initially stabilized and then rose slightly by 2 centimetres.

Update on historic low flows

The Danube reached a new historic minimum flow of 1,400 cubic metres per second – two days earlier than hydrologists had forecast – falling below the previous low recorded in 2003. This is nearly three times lower than the multi-year average for August of 3,900 m³/s, according to Ana Maria Agiu, spokesperson for the National Administration “Romanian Waters” (ANAR).

Navigation on the river has already been disrupted for more than two weeks. At Cernavodă, the water level stood at –217 cm, 2 cm higher than in recent days. Earlier forecasts had pointed to a drop to –233 cm around Friday; that timeline has now been extended at least until the start of the following week.

Agiu noted that loading of the final barge was being completed that day, with experts carefully assessing strong local currents to ensure the controlled sinking could be carried out safely for personnel. Once successful, the effects on water levels are expected to appear quickly.

The intervention aims to raise the Danube level in the Cernavodă area by up to 10–12 cm. This would offset the previously forecast daily drop of about 2 cm and help bridge the gap until upstream precipitation (mainly from Austria) begins to influence flows on the Romanian stretch of the river. The optimal inflow for reliable plant operation is around 2,000 m³/s at Romania’s entry point; even an extra 100–200 m³/s would help maintain minimum levels needed for the plant.

Background to the emergency measures

Two of the barges were loaded with rock material at the site of the Pârjoaia rock displacement on the Old Danube channel; the other two were brought from Galați. Heavy excavators (35 and 60 tonnes) equipped with hydraulic breakers crushed remaining rock after earlier controlled detonations so it could be loaded onto the barges. Sinking was expected after 14:00 once the last barge was ready.

Romanian military forces had carried out further detonations of the Pârjoaia rock earlier in the week to help divert flow from the Bala branch toward the Old Danube channel that supplies the plant. Interim Defence Minister Radu Miruță described the earlier stages as successful and noted that each additional day of plant operation is roughly three times more valuable financially than the cost of these interventions. He welcomed the 2 cm rise, calling it a net gain of at least 4 cm relative to the previous downward trend.

Unit 1 at Cernavodă was already shut down earlier in the week, cutting domestic electricity production by about 10% during a period of elevated consumption driven by extreme heat. Continued low flows raise the risk that Unit 2 could also face restrictions or shutdown.

Romania shuts nuclear reactor as Danube runs dangerously low

These emergency engineering works form part of broader efforts across the region to manage the impact of prolonged drought and record-low Danube levels on nuclear generation, including similar challenges faced at Hungary’s Paks plant.

Hungary’s NPP faces weeks-long shutdown as record-low Danube levels threaten regional power supplies

The article in Romanian by EUalive’s partner Espress.ro can be found here.

Caption: River barges transporting goods pass near the Cernavoda Nuclear Power Plant, traveling along the Danube–Black Sea Canal in Cernavoda, Romania, 5 August 2026. The Cernavoda Nuclear Power Plant relies on water drawn from the Danube River to cool its reactors. On 3 August 2026, military engineers and navy divers used explosives to blast underwater rock formations on a branch of the Danube, seeking to improve the flow of cooling water to the plant as Danube’s water levels dropped to historic lows. The plant typically supplies approximately 20 percent of Romania’s total electricity demand when both reactors are fully operational. On 31 July, the government declared a nationwide state of alert for August to manage the impact of electricity shortfalls. EPA/ROBERT GHEMENT