Czech Minister Martin Šebestyán pushes plan to raise Nové Mlýny reservoirs after fish die‑off

Hundreds of fish died at the Bulhary dam on the Dyje River after extreme heat, low flow and cyanobacterial blooms depleted oxygen. The loss was estimated at about one tonne, far less than in previous years thanks to rapid response by the Morava River Basin Authority, firefighters and anglers.

Minister of Agriculture Martin Šebestyán and Morava River Basin director David Fína said the most effective preventive measure is the planned raise of the Nové Mlýny reservoir water level by 35 cm. The higher level would store more water for release during dry periods, improve river flow, increase oxygenation and protect aquatic life, as well as benefit groundwater stability and irrigation.

Implementation is blocked by a lawsuit from an environmental organisation, with the case now before the Czech Supreme Administrative Court. Šebestyán noted that the ministry has appealed the regional court’s verdict and is awaiting a final decision. Meanwhile, the basin authority has taken precautionary steps, including shutting down a small hydro plant, installing new oxygen sensors, expanding water‑quality monitoring and using drones to track conditions.