It was a monumental disaster. The dynamiting of the Kakhovka dam on Ukraine’s Dnieper River, just before dawn on June 6, 2023, rapidly emptied Europe’s largest hydroelectric reservoir. Some 14 million acre-feet of water hurtled downstream for more than 100 miles to the sea. Around 80 villages were flooded, more than 100 people died, and more than 40 nature reserves were engulfed. In the Black Sea, the flood delivered a flush of industrial toxins, land mines, agricultural chemicals, sediment, and fresh water that killed fish and unleashed swarms of algae along the coast.
Ukraine’s president, Volodymyr Zelensky, called it the “largest man-made environmental disaster in Europe in decades”—since the meltdown at the country’s Chernobyl nuclear plant in 1986. Within days, his government pledged to rebuild the dam.
But now the ecological consequences of this war crime—widely presumed to be perpetrated by the dam’s Russian occupiers—are being seen in a different light. The bed of the former reservoir is rapidly rewilding, with extensive thickets of native willow trees growing. The country’s ecologists are calling for plans for a new dam to be dropped, in favor of nurturing the ecological renewal. And they argue that some of Ukraine’s short-term wartime environmental catastrophes—on rivers, in forests, and across the country’s precious steppe grasslands—can be turned into long-term ecological gains.
“War-wilding” can benefit a country still chained to Soviet-era infrastructure, they say. After the war ends—which Zelensky said during a visit to the United States in September could be “closer… than we think”—Ukraine could secure its inadvertent ecological gains and ensure that reconstruction puts the environment at its heart.
There is no doubt that the breaching of the Kakhovka dam 16 months ago was a catastrophe for people living downstream. Many ecosystems were badly damaged. The question now is whether and how nature will recover. At least in the 155-mile length of the drained reservoir, the prognosis is remarkably positive.
Ecologists initially warned that the sediments exposed on the reservoir’s bed would either turn to desert and unleash dust storms laced with toxic detritus, or else be invaded by alien species. Neither has happened, according to Anna Kuzemko, a botanist at the M.G. Kholodny Institute of Botany in Kyiv, who has made three field trips to the reservoir bed, during one of which she was shelled by Russian mortars. The river has resumed its flow down old channels. Sturgeon have made it upstream to old spawning grounds near the dam. Nourished by rich sediment, native willows have grown across the reservoir floor, with reed beds fringing water courses.
During her most recent visit, in May, Kuzemko found that the new willow trees had reached an average height of three meters. “We were amazed. They are growing by a centimeter each day,” she says. “At an international symposium of vegetation science in September, we concluded that the young forest at the bottom of the former reservoir is now the largest floodplain forest in Europe.”
The situation downstream is less clear. The river below the dam site is on the war’s front line, with Ukraine’s forces on the west bank and Russia occupying the east bank. The toxic floodwaters here soon abated, but field trips to check out their longer-term impact on ecosystems are currently impossible. Even so, as the initial damage recedes, “downstream floodplains are likely to restore quickly, as they are adapted to flooding,” says Eugene Simonov, a freshwater ecologist and founder of the activist group Ukraine War Environmental Consequences Work Group (UWEC).
In any case, local ecologists are sufficiently enthusiastic about the rewilding of the extensive reservoir bed that they want the newly liberated river to remain free. It is “a unique chance to learn about the self-restoration capabilities of a major European river,” says Simonov, who is currently studying at the University of New South Wales in Australia. He anticipates the permanent return of what, before Soviet engineers arrived in the 1950s, was known as the Velykyi Luh, or Great Meadow, a region of steppe grassland and swamp previously prized for its archaeological remains and Cossack history, as well as its ecology.
The restoration of the Velykyi Luh would be “the largest freshwater restoration project ever carried out in Europe,” says Oleksii Vasyliuk, head of the Ukraine Nature Conservation Group, which works to identify and establish protected areas across the country. “Ukraine has a chance to restore its natural and historical heritage,” says Kuzemko. “We must not waste this chance.”
The gains from eschewing a new dam would be economic and political, as much as ecological, the ecologists argue. In the Soviet era, which ended in 1991, Ukraine was a bastion for building inefficient infrastructure that took a heavy toll on nature. Engineers installed a cascade of six hydroelectric dams on the Dnieper, Europe’s fourth longest river. The last and largest of them, the Kakhovka dam, was constructed on a floodplain, with much of its reservoir often only a few feet deep.
Kakhovka took 830 square miles of flooded land to provide just 357 megawatts of generating capacity. That is more than three times the land take for America’s Hoover Dam, to deliver less than a fifth of the power. Simonov calculates that, rather than rebuilding this “Soviet monster,” the same energy capacity could be delivered by installing solar panels across fewer than 10 square miles, little more than one percent of the area flooded by the original dam.
A further reason for Ukraine not to rebuild large dams is that they would be vulnerable to future sabotage. By approving an aid package providing the country with small energy systems, including solar power, Germany’s minister for economic cooperation and development, Svenja Schulze, said in September that her government was supporting “a decentralized power supply infrastructure, as Russia will then not be able to destroy it so easily.”
The conflict in Ukraine has added a new term to the environmental vocabulary: war-wilding. It was coined by British academic Jasper Humphreys, who studies the impact of armed conflict on nature at the Department of War Studies in Kings College London. He says it came to him at the start of the Russian invasion in February 2022, when Ukraine halted the advance on Kyiv of hundreds of tanks by breaking the Kozarovychi dam on the Irpin River. Besides saving the nation’s capital, the inundation of some 6,000 acres of farmland downstream restored the river’s natural floodplain.
Now, like the Kakhovka dam, the fate of the Kozarovichy dam and the reborn Irpin floodplain hang in the balance. Irpin city authorities want to rebuild the old Soviet structure, redrain the floodplain, and revive prewar plans for a massive new housing development there. But Volodymyr Boreyko, director of the Kyiv Environmental and Cultural Center, has received strong support for his call for the Irpin to be declared a “River Hero” of the conflict, and kept natural, with beavers swimming its length and water buffalo grazing the floodplain.
While its wrecked hydroelectric dams have attracted the most headlines, Ukraine’s forests have also been in the front line of the war. They provide much-needed cover against drone surveillance. With much of the fighting happening in and around them, they are also vulnerable to fires ignited by munitions. But they can also benefit from war-wilding.
UWEC’s scientists estimate that a quarter-million acres have burned during the conflict. That sounds bad, but according to Stanislav Viter, a forest ecologist at the National Academy of Sciences of Ukraine, the losses are “significantly smaller than those resulting from logging and various fires in peacetime.” In fact, the absence of loggers has meant that “some areas of frontline forests… are increasingly reminiscent of protected areas,” he says.
The forest war-wilding may continue long after the war is over, according to Valentyna Meshkova, head of Ukrainian government’s Laboratory for Forest Protection. Many forests on the front line are now dotted with minefields that could take decades to clear. Mines are bad news for large forest animals such as elk. But they keep away humans, preserving habitat for many smaller mammals, invertebrates, birds, and plants.
She likens the potential ecological benefits of the minefields to the large-scale regeneration of forests in the radioactive exclusion zone created in 1986 around the site of the Chernobyl nuclear disaster in the far north of the country. In the absence of human activity, natural regeneration has increased forest cover there by almost 50 percent. With more than two-thirds of the exclusion zone now tree-covered, it has been designated a nature reserve, Europe’s third largest.
Nobody knows when the war will end, and whether it will result in Ukraine holding on to all its former territories. But plans for reconstruction are being laid, and many of the country’s ecologists argue that if those plans put nature first, that will be a valuable credential in the country’s application to join the European Union.
The EU is committed to achieving massive ecological restoration in the coming decades, but has not yet worked out how or where. As Vasyliuk notes, “the only place in Europe where we can see large-scale recovery of nature is the part of Ukraine which has suffered from military action.” With many areas likely to remain off-limits for decades after the war because of mines or munitions contamination, he says Ukraine could let nature deliver environmental gains on a scale that “until now had seemed pretty distant and unrealistic.”
But this is far from a given. While many of the country’s forests could be winners in the aftermath of the war, there is growing concern that the big ecological losers could be the country’s precious unfenced steppe grasslands.
Ukraine has many of Europe’s last surviving such steppe landscapes. They are home to a third of the nation’s endangered species, including the much-loved, endemic sandy blind mole-rat. Several of these areas are currently occupied by Russian military, including the country’s oldest protected area, the 128 square-mile Askania-Nova biosphere reserve on the east bank of the Dnieper River. Russian forces have dug extensive fortifications there and ignited large fires.
Fire is a natural phenomenon in steppe regions, says Viktor Shapoval, the exiled director of the reserve. So, he hopes that recovery can be swift. But arguably a bigger concern is that, even as the war continues, Ukraine’s foresters are planting trees on these rich steppe grasslands to make up for lost commercial forests in the war zone. Viter says almost 27,000 acres were planted in the 22 months prior to the end of 2023. He fears that, with minefields leaving many forests out of bounds for the foreseeable future, the cessation of hostilities will only accelerate the foresters’ annexation of steppe ecosystems.
The stakes are high for the ecological future of Europe’s second largest country, after Russia. From its revived river floodplains to the mined forests of the eastern war zone and its prized but perilously under-protected steppes, “the potential for war-wilding is huge,” says Humphreys. But much could go wrong. When the artillery finally falls silent, and the drones go home, the country will face a choice — whether to build back old Soviet infrastructure and carry on as before, or to become a beacon for a greener and more sustainable Europe.
