More than 80 municipalities gradually engulfed on the banks of the southern Dnieper, Kherson evacuated in emergency, potential drying up of the North Crimean canal, difficulties in cooling the Zaporizhia nuclear power plant, potential ecological disaster… Ukrainian officials have been identifying, since Tuesday, June 6 in the morning, the devastating consequences of the explosion of the Nova Kakhovka hydroelectric dam located in territory occupied by Moscow, which has been pouring torrents of water downstream for several hours. At the heart of strategic issues since the start of the war, it was, according to Ukraine, dynamited by Russian forces on the night of Monday to Tuesday.
“Around 2 a.m. there were a number of repeated strikes on the Kakhovka hydroelectric power station, which destroyed the valves. As a result, water from the Kakhovka reservoir began to flow uncontrollably downstream “, declared, according to the Russian agency TASS, the mayor of the city of Nova Kakhovka, Vladimir Leontiev. Oleksandr Prokudin, head of the Kherson regional military administration, meanwhile announced in a video posted on Telegram shortly before 7 a.m. that “the Russian army has committed a new act of terror” and warned that water would reach “critical levels” within five hours. The Ukrainian government called for an emergency meeting of the UN Security Council on Tuesday morning. “Russia is at war against life, against nature, against civilization”, reacted, for his part, on Telegram, President Volodymyr Zelensky, who accuses the Russians of having “mined” the dam before doing so. “explode”.
One of the largest hydroelectric dams in the country
The dam is located on the Dnieper River, upstream from Kherson. Built partly of concrete and earth, the structure is 16 meters high and 3,850 meters long. It retains more than 18 million cubic meters of water in the artificial Kakhovka reservoir, which is 240 kilometers long and up to 23 kilometers wide. It is one of the largest infrastructures of this type in Ukraine. It also includes a hydroelectric plant (with a capacity of 334 megawatts (MW) according to the operating company Ukrhydroenergo), and a road bridge, now destroyed.
Built in 1956 during the Soviet period, the purpose of the dam was both to regulate the course of the river on its last, much narrower stretch, and to send water into the North Crimean Canal, whose adduction is sheltered by the structure. Currently, millions of cubic meters flow from the lake and into the southern part of the Dnieper, on the banks of which dozens of villages are built. On both sides, these could be engulfed by the gradual rise of the water in the hours to come. According to local authorities installed by Moscow, the water rose to a level between 2 and 4 meters.
24 villages already flooded, 80 threatened
In October 2022, Volodymyr Zelensky was already warning of the chain disasters that would result from the damage to the infrastructure. “More than 80 localities, including Kherson, would find themselves in the zone of rapid flooding”, he claimed then, and “it could destroy the water supply of a large part of southern Ukraine” if the canal from Northern Crimea (a zone occupied by Moscow since 2014) is no longer supplied. According to Ukrainian Interior Minister Igor Klymenko, 24 villages were already flooded around 1 p.m., and a thousand people had already been evacuated. “About 16,000 people on the right bank of the region are in the critical zone,” said the head of the region’s military administration, Oleksandr Prokudin in the morning.
According to estimates from a computer model created by the Swedish blog Cornucopia in October 2022, which models the worst-case scenario in the event of a breach in the dam, it would take around 19 hours for water to reach Kherson. “If Kherson is on the highest bank, some neighborhoods are completely flood-prone, even if, close to the river, they were probably almost exclusively occupied by Ukrainian soldiers”, points out the historian and consultant in international risks. Stephane Audrand on Twitter. On Telegram, the railway company Ukrzaliznytsia announced to increase the traffic of its trains to speed up the evacuations, and affirms that the first evacuation train leaves Kherson at 12:00 (11:00 in Paris). “Additional evacuation trains will be scheduled if necessary,” she adds.
The security of the Zaporizhia power plant threatened?
The dam, which held back more than 18 million cubic meters of water, also allows the Zaporizhia nuclear power plant located 150 kilometers upstream – in the “energy capital of Ukraine, Enerhodar – to supply itself with water from cooling. As the water level drops in the Kakhovka reservoir, the Ukrainian government is very alarmist on the subject. “The world is once again on the brink of a nuclear catastrophe”, because the nuclear power plant, the largest in Europe, “has lost its source of cooling” and “this danger is now increasing rapidly”, lamented the adviser to the Ukrainian presidency Mykhaïlo Podoliak.
But the International Atomic Energy Agency (IAEA) is tempered. On Twitter, she said her experts are “closely monitoring the situation” after seeing “reports of damage”, and announces for the moment that there are “no immediate security risks. nuclear plant”. An opinion shared by nuclear risk specialist Stéphane Audrand, who explains that “the units are in hot/cold shutdown and water requirements are low to ensure residual cooling of the fuel in the cores and in storage”. On the other hand, the explosion “will complicate the possible restarting of the Energodar nuclear power plant, which before the war represented 6,000 MW of installed power and 23% of Ukraine’s electricity production…”, estimates- he.
Natural and health disaster
The banks of the southern part of the Dnieper are also home to green nature. Many actors in Ukraine today denounce an “ecological disaster” in addition to a war crime. According to Mykhailo Podolyak, senior adviser to President Volodymyr Zelensky, “a global ecological disaster is playing out now, and thousands of animals and ecosystems will be destroyed in the next few hours.” Videos posted online show Beavers rushing to the heights because of the rising waters.
After the explosion of the plant, “one hundred and fifty tons of engine oil” spilled into the Dnieper River on Tuesday morning, Ukrainian officials said, warning of an environmental risk. In a press release, the Ukrainian presidency then quantified the “risk of additional leakage” at “more than 300 tonnes”, denouncing “ecocide”. “Environmental damage is of particular concern,” said Ukrainian Foreign Minister Dmytro Kuleba.
Ultimately, if evacuations are carried out and civilian casualties avoided, the explosion should also cause health problems in the flooded area, according to Stéphane Audrand. “As a reminder, in regions in medical tension, the bulk of civilian casualties are caused by poor sanitation and the diseases that come (especially in the hot season) with the flood (typhus, dysentery, etc.), recalls- he.