Severe heat and drought have pushed parts of the Danube and Rhine to record-low water levels, disrupting transport, electricity generation and tourism across central and eastern Europe. The situation matters because low river levels have forced nuclear reactors to reduce or halt operations, raising concerns about power shortages while shipping routes become increasingly unusable.

Hungary’s Paks nuclear plant, which supplies nearly half the country’s electricity, was operating below 50% capacity and could shut down for weeks; Romania also suspended one reactor and planned to stop another. Cargo vessels on the Danube have largely stopped or cannot travel fully loaded, while Budapest sightseeing cruises have been cancelled, but the retreating water has exposed wartime wrecks, a bomb and woolly mammoth remains in Bulgaria. With little rain forecast and temperatures expected to exceed 38C, conditions were expected to worsen.