Serhiy Kraskov picked up a twig and poked at a small fish floating in the Desna River. “It’s a roach. It died recently. You can tell because its eyes are clear and not blurry,” he said. Hundreds of other fish had washed up nearby on the river’s green willow-fringed banks. A large pike lay in the mud. Nearby, in a patch of yellow lilies, was a motionless carp. “Everything is dead, starting from the tiniest minnow to the biggest catfish,” Kraskov added mournfully.
Kraskov is the mayor of the village of Slabyn, in Ukraine’s northern Chernihiv region. The rustic settlement – population 520 – escaped the worst of Russia’s 2022 full-scale invasion. But the war arrived last week in a new and horrible form. Ukrainian officials say the Russians deliberately poisoned the Seym River, which flows into the Desna. The Desna connects with a reservoir in the Kyiv region and a water supply used by millions.
A toxic slick was detected on 17 August coming from the Russian border village of Tyotkino. According to Kyiv, chemical waste from a sugar factory had been dumped in vast quantities into the Seym. It included ammonia, magnesium and other poisonous nitrates. At the time, fierce fighting was going on in the surrounding area. Ukraine’s armed forces had launched a surprise incursion into Russia and had seized territory in Kursk oblast.
The pollution crossed the international border just over a mile away and made its way into Ukraine’s Sumy region. The Seym’s natural ecosystem crashed. Fish, molluscs and crayfish were asphyxiated as oxygen levels fell to near zero. Settlements along the river reported mass die-offs. Kraskov got a call from the authorities warning him a disaster was coming his way. He spotted the first dead fish on 11 September. “There were a few of them in the middle of the river,” he said.
He returned the following weekend to find the Desna’s banks clogged with rotting fish, stretching out from the shore for three metres into the water. Volunteers wearing rubber boots, masks and protective gloves shovelled the fish into sacks. They found a metre-long catfish. “The stench was terrible. You could scarcely breathe. The river was quiet. Nothing moved apart from a few frogs,” Kraskov said. A tractor took the sacks to an abattoir that used to belong to the village’s Soviet-era collective farm. They were buried in a pit.
Serhiy Zhuk, the head of Chernihiv’s ecology inspectorate, described what had happened as an act of Russian ecocide. “The Desna was one of our cleanest rivers. It’s a very big catastrophe,” he said. Zhuk traced the slick’s route on a map pinned to his office wall: a looping multi-week journey along the Seym and Desna. “More than 650km is polluted. Not a single organism survived. This is unprecedented. It’s Europe’s first completely dead river,” he said.
In his view, the Kremlin was waging total war of a kind not seen since the last century. Vladimir Putin’s desire to eradicate Ukraine extended to the natural world, he suggested. “They are sending rockets through the air, burning our forests and threatening to blow us up with nuclear bombs. You can rebuild a bridge or a school. It takes longer, unfortunately, for wildlife to recover.”
As the contamination approached, Zhuk ordered the closure of Zolotyi Bank, the central beach in Chernihiv. A ban was imposed on fishing, swimming, and on using the river to water cattle or gardens. Scientists took samples, testing every 15-20km and bringing glass vials back to a laboratory. The results were hair-raising. In the city of Baturyn, a one-time Cossack capital on the Seym, oxygen content dipped to zero on 29 August. The next day it was 0.1 mg/dm³. At least 4 mg/dm³ is needed for fish to breathe.
Zhuk said it would take years for the river to recover. There was little prospect of this happening while fighting in Russia’s Kursk oblast continued, he said. Ukraine’s armed forces have blown up bridges over the Seym, adding fuel and debris to an already noxious mix. Around Chernihiv, local helpers – some in boats – collected about 44 tonnes of dead fish. “That’s what we recovered. There’s a lot more inside the river and on the bottom,” Zhuk said.
Emergency teams have used compressors to pump oxygen into the Desna, to give the remaining fish a better chance of survival. Recent rains dispersed some toxins. Zhuk was optimistic these measures would be enough to save Kyiv from the worst of the pollution. But he admitted the situation was grim. “There is a difference between a natural and man-made disaster. This was a diversionary act. Russia’s ecological genocide won’t stop until the war stops,” he said.
At the central beach, Olha Rudenko and her boyfriend Roman Svichkar strolled along the golden sands. A sign in red letters warned “Do not bathe”. “This is a huge eco-tragedy. The river smells weird,” Olha remarked. She noted that last year Russian troops blew up the Khakovka reservoir in Ukraine’s southern Kherson province, flooding villages and killing people and fish. “This is Russia again, 100%,” she said. “We used to drink water from the tap and buy fish from the market. Now we can’t.”
Svitlana Hrynchuk, Ukraine’s minister for environmental protection, said water consumption in Kyiv remained safe. Various special measures had been taken to get rid of the nitrates, she said, with 120 tonnes of cleaning agents imported and nets strung across the Desna to catch dead fish. In the Kyiv region, none had turned up. Additionally, water was routinely purified before it was extracted for household use, she said, adding: “We don’t have a fish plague.”
Hrynchuk said this latest episode was part of a dismal pattern. Russian troops had destroyed national parks in occupied areas, killed animals and mined thousands of hectares of forest. Explosions had caused wildfires, a problem exacerbated by recent hot weather. “Ukraine is fighting for its future. That future has to include nature. We need clean water, clean air, woods, everything,” she said. “We have a beautiful country. We have to save and protect it.”
She said the river was a part of Ukrainian culture. In 1956, the Soviet film-maker Oleksandr Dovzhenko published a novel called The Enchanted Desna. Reminiscing about his childhood, he wrote: “It would be long past sunset and the large catfish would leap in the Desna under the stars as we listened agog till we dozed off in the fragrant hay under the oaks. Grandpa regarded the tench as the best fish of all. He scooped them right out of the water with his bare hands like a Chinese magician.”
Back at Slabyn, Kraskov said that before he became village mayor he worked at Chornobyl nuclear power station. He was involved in the construction of a concrete sarcophagus designed to contain radiation from the reactor, which blew up in 1986. “I know how to bury dangerous substances,” he said wryly. “I also know how bureaucracy works. That’s why we acted quickly with the dead fish.” He continued: “If something goes wrong, officials like to find a scapegoat. So you better do everything correctly. Our life is like this.”
