Threat of the Dnieper reservoirs

The water reservoirs of the Dnieper River in Ukraine pose a significant threat of a large-scale human-made disaster if their dams fail. Such a threat is typical for reservoir dams; however, the Dnieper reservoirs are especially dangerous because of the geographical conditions, as well as the consequences of the Chernobyl disaster and other nuclear-related environmental threats in the region.

Like other reservoirs, Dnieper reservoirs pose a potential threat of causing major flooding if their dams fail. Such damage may be inflicted by a powerful natural disaster (e.g., an earthquake), a human-made disaster, or a deliberate attack by terrorists or enemy forces at war.

The Dnieper reservoirs contain an additional major threat—after the Chernobyl Nuclear Disaster in 1986, radionuclides washed away by rains badly contaminated the bottom silt of the Kiev Reservoir and presumably the others. During the years following the disaster, there were suggestions to drain the Kiev Reservoir because it was too shallow. It appeared that, if done, this could have created the threat of the tremendous amounts of radioactive dust travelling by wind, lethally affecting Europe.

The dams are supposed to be strong enough to survive natural and terrorist threats. Both their construction schemes and government efforts work towards this goal. For instance, some engineers guarantee that every Dnieper dam will survive an earthquake (to its typical regional extent), meteorite or aircraft falling. There are also countermeasures against overflooding and malfunction of dams. Authorities pay significant attention to safeguarding the dams and bridges by special units of the Ministry of Internal Affairs and other security agencies.

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Wikipedia