Romania and Hungary halt nuclear reactors amid record‑low Danube water

Danube low water Cernavodă reactor shutdown Paks output reduction nuclear cooling electricity imports

The Danube’s flow fell to a historic low of 1,750 m³/s on 16 July, the lowest level recorded in three decades. At the same time, water levels at Hungary’s Paks site dropped to –106 cm on 27 July and later to –118 cm, both unprecedented records.

Romania’s Cernavodă nuclear plant shut down Unit 1 (≈ 700 MW, about 20 % of national electricity) on 28 July because the river could no longer provide sufficient cooling water. Operators warned that Unit 2 could be taken offline if the low‑water situation persisted, with the shutdown expected to last at least until early August.

In Hungary, the Paks Nuclear Power Plant first reduced output of Block 1 by 254 MW on 27 July and then began a controlled shutdown of Block 3 (≈ 750 MW) on 29 July, cutting the plant’s capacity to roughly 60 % of its normal output. Emergency measures such as floating pumps and cranes were placed on the river to secure cooling water.

Romania anticipates importing up to 1,700 MW during evening peak demand, while Hungarian officials say the national electricity supply remains secure despite the reductions.

Entities: Cernavodă Nuclear Power Plant · Cernavodă Nuclear Power Plant · Danube River · Hungary · Ilie Bolojan · László Gajdos · MVM (Hungarian nuclear operator) · Nuclearelectrica · Paks Nuclear Power Plant · Paks Nuclear Power Plant · Romania · Romanian Ministry of Energy

Claims

What the coverage asserts, and how well corroborated each claim is across sources.

[● 9 SOURCES] Both Cernavodă and Paks nuclear plants use Danube water for cooling, and low flow threatens nuclear safety. (All articles referencing low Danube water affecting both plants)
[● 7 SOURCES] Hungary reduced output of block 1 at Paks by 254 MW on July 27 because of low Danube water level. (existing)
[● 3 SOURCES] The Danube water flow was measured at 1,750 cubic metres per second on July 16, the lowest in three decades. (existing)
[● 4 SOURCES] Hungary reduced output of block 3 at Paks by 237 MW starting at 20:00 on July 28. (existing)
[● 5 SOURCES] Romania shut down unit 1 of the Cernavodă nuclear power plant on Tuesday due to low Danube water flow. (existing)
[● 4 SOURCES] Cernavodă nuclear plant supplies about 20 % of Romania’s electricity. (existing)
[● 7 SOURCES] The Danube water level at Paks was measured at –106 cm on July 27, a record low. (existing)
[● 4 SOURCES] The shutdown of unit 1 is expected to last until at least August 4. (existing)
[● 3 SOURCES] Romania may need to import about 1,700 MW of electricity during evening peak consumption because of the reactor shutdown. (existing)
[○ 1 SOURCE] Danube water flow measured 1,750 cubic metres per second on 16 July, the lowest in 30 years. (Nuclearelectrica / Romanian water authorities)
[● 3 SOURCES] A second reactor at Cernavodă could be shut down if Danube water levels continue to fall. (existing)
[○ 1 SOURCE] The Cernavodă reactor is expected to restart no earlier than 4 August. (Nuclearelectrica)