France's drought lowers river water levels, EDF shuts down three nuclear reactors

Affected by drought weather, water flows in France's Meuse and Moselle rivers have declined, and Électricité de France (EDF) has shut down three nuclear reactors in northeastern France. As of the afternoon of August 3, Units 1 and 2 at the Chooz Nuclear Power Plant in the Ardennes department, as well as one unit at the Cattenom Nuclear Power Plant in the Moselle department, remained offline.

EDF shut down Unit 1 at the Chooz plant on Saturday evening to comply with the Meuse River management agreement signed between France and Belgium in 1998. Under the same agreement, Unit 2 at the Chooz plant has been offline since July 11. EDF stated that the agreement allows for adjustments to power generation arrangements based on hydrological conditions to safeguard water usage for users along the Meuse River in both France and Belgium.

Due to declining water levels in the Moselle River, EDF also proactively shut down one unit at the Cattenom Nuclear Power Plant overnight from Friday to Saturday. Meanwhile, the company has reduced or plans to reduce output at four other units, including Unit 3 at the Bugey Nuclear Power Plant, Unit 4 at the Tricastin Nuclear Power Plant, and Units 1 and 2 at the Saint-Alban Nuclear Power Plant.

France currently operates 57 nuclear reactors, with nuclear power accounting for approximately 70% of the country's total electricity generation. Nuclear power plants are typically built near rivers or coastlines, primarily because reactor operations and turbine systems require large amounts of cooling water. During droughts and heatwaves, reduced river flows and elevated water temperatures may force operators to limit unit output or suspend power generation.

These restrictions are primarily aimed at protecting aquatic ecosystems, avoiding the discharge of cooling water or the release of certain chemical and radioactive liquid effluents under low-water and high-temperature conditions, which could further raise river water temperatures. On Monday, as extreme heat weather persisted, yellow heat warnings were issued for France's Ardennes and Moselle departments.