Low Danube levels expose Europe’s hidden water-energy risk

Record-low water levels on the Danube are turning Europe’s summer drought into an energy-security problem, with nuclear cooling, hydropower, inland shipping and industrial activity all exposed to the same low-flow stress.

The Associated Press (AP) reported that the Danube in Budapest fell to 10 cm, below the previous record of 33 cm in 2018. AP described the situation as ‘pushing parts of Eastern Europe towards an energy emergency’ as heat and low river flows converged.

Lack of cooling-water supply

The pressure is visible in Hungary, where low water levels have affected operations at the Paks nuclear power plant. The plant normally supplies a large share of the country’s electricity, making river temperature and flow a direct operational factor for the energy system. Romania has faced similar pressure around the Cernavoda nuclear plant. The Guardian reported that authorities used controlled blasts to divert Danube water towards the plant after low levels threatened cooling-water supply. The report said the intervention was intended to keep enough water moving towards critical infrastructure.

Hydrological stress affects several sectors

The Danube case shows how hydrological stress can affect several sectors at once. Navigation, power generation, cooling-water access, hydropower output and industrial continuity all depend on the same river conditions. The Hungarian Hydrological Forecasting Service (HFS) has warned that some locations on the Danube and Tisza may fall below observed historical minima. In practical terms, that means operators are working close to or beyond the envelope used for historical planning.

Water-energy nexus

The current problems show the water-energy nexus is crucial. No energy without water. And no water without energy. It is as simple as that. The complex ‘nexus’ between energy and water is getting more complicated every day due to the increasing fresh water shortage. Cooperation is needed to solve this problem. Nowadays considering ‘water’ and ‘energy’ as separate utilities is a dead end street. Efficient ‘water-energy’ solutions are needed to safeguard our future that will be determined by climate change and population growth.