News

Apr 30, 2023

Russia

Kyiv June 7, 3:29 p.m. Moscow June 7, 3:29 p.m. Washington June 7, 8:29 a.m. As

Kyiv June 7, 3:29 p.m.

Moscow June 7, 3:29 p.m.

Washington June 7, 8:29 a.m.

As residents sought safety from engulfed communities, President Volodymyr Zelensky warned that hundreds of thousands could lack drinking water.

Victoria Kim and Andrew E. Kramer

Rescue workers pressed ahead on Wednesday to evacuate people across an expansive area of southern Ukraine flooded by the destruction of the Kakhovka dam a day earlier, as another humanitarian disaster unfolded along the front lines of the war.

Floodwaters, which were expected to peak Wednesday morning, engulfed streets and homes in dozens of communities, sent residents fleeing on boats, and dislodged roofs that floated away. According to Ukrainian officials, an estimated 16,000 people were at risk on the Ukrainian-controlled western bank of the Dnipro River, and 25,000 more would need to be evacuated on the eastern bank, which is under Russian control.

As the scale of the disaster began to come into focus, President Volodymyr Zelensky of Ukraine said that hundreds of thousands of people were "without normal access to drinking water" and that the emergency services were working to provide assistance in Ukrainian-controlled areas.

The Russian-installed administrators of Nova Kakhovka, the city adjacent to the dam and attached hydroelectric plant, said floodwaters had begun receding Wednesday morning. Seven people were reported missing, they said, while cautioning that those were preliminary figures.

Experts said a deliberate explosion inside the dam, which has been under Russian control since early in the war, most likely caused the massive structure of steel-reinforced concrete to crumble. Moscow blamed Ukraine, calling the blast an act of sabotage, but did not elaborate on how it might have been done. Mr. Zelensky said Russian forces had blown up the dam to "use the flood as a weapon."

But he said that the destruction of the dam would "not affect Ukraine's ability to de-occupy its own territories," an apparent reference to a counteroffensive by Ukrainian forces that American and Russian officials said this week might have begun east of the Dnipro.

Here are the latest developments:

Ukrainian officials said that in addition to the humanitarian crisis, the flooding would cause a widespread ecological disaster. Mr. Zelensky said an oil slick of "at least 150 tons" was being washed out to the Black Sea and that untold chemicals, fertilizers and oil products in the flood regions would end up in the rivers and the sea.

The flooding could also increase the risk posed by land mines by exposing underground mines planted on the banks of the Dnipro River by Russian and Ukrainian forces and washing them downstream, according to the United Nations and groups working to clear the mines.

Evacuees were arriving in Ukrainian cities including Mykolaiv, a southern city already strained by people who fled the war and by continued Russian attacks. The U.N. warned that the flooding "will likely worsen an already fragile humanitarian situation," and that thousands of children were among those fleeing.

Fighting continued to rage on Tuesday and Wednesday. Russia launched 35 long-range missiles of various types and carried out 41 airstrikes over the past 24 hours, Ukraine's military headquarters said in its morning update on Wednesday. Along the front line, soldiers fought in 30 engagements, it said.

Enjoli Liston

Ihor Klymenko, Ukraine's internal affairs minister, said that more than 1,560 people have been evacuated from flood-hit areas so far. A tweet posted by the ministry said 29 settlements had been flooded, of which 19 are in territory controlled by Ukraine.

Emma Bubola

The destruction of the Kakhovka dam will cut off the water supply to hundreds of thousands of acres of farmland, Ukraine's agriculture ministry has warned, underlining the devastating impact of the disaster on an already hard-hit cornerstone of the country's economy.

Ukraine's agricultural sector, which has been a key link in the world's grain supply, has in the past year had its harvests paralyzed by land mines, fires and Russian rockets.

The damage from Tuesday's dam disaster will affect farmlands that before the war yielded millions of tons of grain and oil crops, worth about $1.5 billion, the ministry said in a statement on Wednesday, in what it called a preliminary assessment. Now, 94 percent of the irrigation systems in the Kherson region, 74 percent in Zaporizhzhia and 30 percent in Dnipropetrovsk will be left without a source of water, it said.

"The fields in the south of Ukraine may turn into deserts as early as next year," it said.

The water shortage will not be limited to farmland, but will also affect drinking water supplies in populated areas. President Volodymyr Zelensky said on Wednesday in a post on the Telegram messaging app that "hundreds of thousands of people have been left without normal access to drinking water" by the dam disaster.

The ministry predicted that about 25,000 acres of agricultural land on the east bank of the Dnipro river, which is held by Ukraine, would be flooded. The flooding on the west bank of the river, which is under Russian occupation, will be much more severe, it said.

The ministry said that the fishing industry would also be affected. According to a report by Ukraine's Nature Conservation Group, the dam's reservoir yielded 2.6 thousand tons of fish every year and it could take at least seven to 10 years to restore the stocks.

Adult fish have already died as a result of the dam's destruction, the agriculture ministry said, and the drop in the reservoir's water levels will present a challenge for hatching fish eggs. Fish swept into the Dnipro will likely die when the flood wave hits the salty waters of the Black Sea, the government said.

Even if the reservoir was refilled, the ministry said, the devastating consequences for its ecosystem "will continue for several years," it said.

Areas of confirmed flooding

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Damaged grain

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Tokarivka

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Ivanivka

Korsunka

Nova Kakhovka

Flooded areas

on both riverbanks

Krynky

Dnipriany

Mykilske

Kozachi Laheri

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submerged

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Flooding reported in

multiple villages

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Widespread

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Slavy Park

Oleshky

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reported

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Stara Zbur’ivka

Areas of confirmed flooding

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UKRAINE

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Detail area

Damaged grain

elevator

Mykolaivka

Kakhovka

reservoir

Burhunka

Olhivka

Lvove

Kakhovka

dam

Tianhynka

Odradokam'yanka

Tokarivka

Poniativka

Ivanivka

Korsunka

Nova Kakhovka

Flooded areas

on both riverbanks

Krynky

Mykilske

Dnipriany

Sadove

Kozachi Laheri

Center of

Nova Kakhovka

submerged

Antonivka

Pishchane

Flooding reported in

multiple villages

downstream

of the dam

Prydniprovske

Dachi

Kherson

Bilozerka

Widespread

flooding west

of Kherson

Waterfront

Slavy Park

Oleshky

Highway

Heavy flooding

reported

To Black Sea

Oleshky Sands

Nature Park

Kardashynka

HELD BY

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Stara Zbur’ivka

Areas of confirmed flooding

N

Kakhovka

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UKRAINE

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Kakhovka

dam

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Nova Kakhovka

submerged

Damaged

grain

elevator

Nova

Kakhovka

Dnipriany

Mykolaivka

Burhunka

Pishchane

Olhivka

Lvove

Krynky

Flooding reported in

multiple villages

downstream

of the dam

Tianhynka

Ivanivka

Tokarivka

Kozachi Laheri

HELD BY

UKRAINE

HELD BY

RUSSIA

Poniativka

Flooded

areas on both

riverbanks

Sadove

Heavy

flooding

reported

Highway

Mykilske

Prydniprovske

Oleshky

Antonivka

Dachi

Kardashynka

Kherson

Widespread

flooding west

of Kherson

To Black Sea

Stara

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Bilozerka

5 miles

Note: Satellite image is from before the flooding.

Sources: Planet Labs PBC; Institute for the Study of War with American Enterprise Institute's Critical Threats Project; Google Maps.

By Lauren Leatherby, Lazaro Gamio, Marco Hernandez and Haley Willis

John Yoon

Mykolaiv, a Black Sea port city that was already under strain as a hub for people fleeing fighting, is now offering shelter to evacuees from flood-hit areas near the destroyed Kakhovka dam.

Thousands of people have been forced to flee as a result of the flooding, according to the United Nations Office for the Coordination of Humanitarian Affairs and Ukrainian officials.

"The flooding," the office said, "will likely worsen an already fragile humanitarian situation." Thousands of children were among those fleeing, it added.

Evacuees are traveling in buses and trains to Mykolaiv, as well as to Odesa in the south, Khmelnytskyi in the west, Kropyvnytskyi in central Ukraine and Kyiv, the capital, the U.N. agency said.

Even before the dam's destruction, about 190,000 people were internally displaced across the Mykolaiv region, which lies near the front line and has long served as a transit hub for people leaving the battle-scarred city of Kherson, said Saviano Abreu, a spokesman for the U.N. agency in Ukraine.

More had arrived in the region when Russia occupied Kherson, which lies about 40 miles to the east, but some have returned since Ukraine reclaimed the regional capital late last year.

On Tuesday, people who were newly displaced by the flooding in Kherson began arriving in Mykolaiv on an emergency train. About 160 people displaced by flooding had fled to Mykolaiv and the nearby city of Odesa by Wednesday morning, but more were expected, Mr. Abreu said.

Evacuations were ongoing on Wednesday morning as floodwaters were expected to reach their peak. About 800 emergency responders were involved in the flood response and about 52 people had been rescued, the head of the state emergency service, Serhiy Kruk, said.

The evacuees in Mykolaiv received aid from Ukrainian officials and volunteers from humanitarian agencies, including the World Central Kitchen, the U.N. Refugee Agency and the Red Cross, the regional military administration said.

More than eight million Ukrainian refugees from Ukraine have fled to countries across Europe since Russia launched its full-scale invasion, and five million others have been displaced within Ukraine, the United Nations refugee agency has said.

Paul Sonne

Hola Prystan, a city on the Russian-occupied side of the Dnipro River downstream from the destroyed dam, is 80 percent flooded, in some cases up to the roofs of houses, according to Gennady Nedlyakov, the Russian-installed head of the city administration. More than 200 people were evacuated Tuesday and another 1,000 to 1,500 people would be evacuated Wednesday, Russia's Tass state news agency quoted him as saying.

Paul Sonne

Four villages downstream from the dam on the Russian-occupied side of the Dnipro River — Korsunka, Krynky, Kozachi Laheri and Dnipryany — are completely flooded, in some cases up to the roofs of the houses, the Russian-installed mayor of Nova Kakhovka, Vladimir Leontiev, told the Russian newspaper Izvestia. He said 17 of roughly 900 people rescued were picked up from the roofs of their houses.

Enjoli Liston

President Volodymyr Zelensky said that "hundreds of thousands of people have been left without normal access to drinking water" by the dam disaster. In a post on the Telegram app, he said Ukraine's emergency services were working on the issue, but could only provide help "on the territory controlled by Ukraine."

Paul Sonne

Russian state media are reporting that water levels in the Russian-held city of Nova Kakhovka, next to the destroyed dam, have started to recede, but that waters are still rising in villages downstream.

The New York Times

Drone photographs taken over Kherson showed floodwater in the city's streets, the day after the Kakhovka dam was destroyed.

Enjoli Liston

Ukrainian officials have issued guidance for residents waiting to be evacuated from flood-hit areas. On its website, Ukraine's Ministry of Internal Affairs advises people to pack an "emergency suitcase," turn off electricity and gas supplies to their homes, close windows and doors and move to high ground or the upper floors of houses.

Enjoli Liston

The ministry advises anyone stuck in floodwaters to "take off heavy clothes and shoes," find objects to climb onto and wait for help.

Marc Santora

As Ukrainian rescue workers were racing to pull people from the floods in Kherson on Tuesday, Russian forces launched some 70 attacks on the city, the head of the regional military administration, Oleksandr Prokudin, said on Wednesday.

Marc Santora

The water level in Kherson is expected to rise by an additional three feet or so before subsiding, the head of the Kherson regional military administration, Oleksandr Prokudin, said. As of early Wednesday morning, more than 1,800 houses had been flooded in areas controlled by Ukraine, and more than 1,400 people had been evacuated, he said.

Andrew E. Kramer

The effects on southern Ukraine were becoming clearer Wednesday morning. The agriculture minister said that 94 percent of agricultural irrigation systems in the Kherson region, 74 percent in Zaporizhzhia and 30 percent in Dnipropetrovsk would be left without a water source.

Victoria Kim

At least seven people have been reported missing in the flooding, the Russian state news agency Tass reported, citing the Russian-installed head of Nova Kakhovka.

Andrew E. Kramer

Fighting raged on Tuesday and Wednesday as a humanitarian catastrophe unfolded along the Dnipro River. Russia launched 35 long-range missiles and carried out 41 airstrikes over the past 24 hours, Ukraine's military said in its morning update Wednesday. Along the fron tline, soldiers fought in 30 engagements, it said.

Kwame Opam

The destruction of a pivotal dam in Ukraine was widely condemned at a tense United Nations Security Council meeting on Tuesday during which Kyiv's allies demanded Russia be held accountable for the invasion without directly blaming Moscow for the dam's collapse.

"It was Russia that started this war, it was Russia that occupied this area of Ukraine, and it was Russian forces that took over the dam illegally last year and have been occupying ever since," Ambassador Robert Wood, a United States representative to the U.N., said.

Ukraine and Russia have blamed each other for the collapse of the Kakhovka dam early Tuesday morning. Ukraine claims Russia detonated a bomb inside the structure, while the Kremlin has said Ukrainian saboteurs destroyed it. Whoever was responsible, Ukrainians and Russians on both sides of the Dnipro River must contend with a massive disaster.

During the meeting, the Russian ambassador, Vasily Nebenzya, again laid blame on Ukraine for the dam's collapse, calling it an "unthinkable crime." Mr. Nebenzya painted the dam's destruction as part of a Ukrainian plan to improve its position for a counteroffensive and to intimidate the civilian population. "We call on the U.N. Secretary General to finally give an objective assessment of the terrorist actions of the Kyiv regime and condemn them," he said.

But the Ukrainian ambassador, Sergiy Kyslytsya, addressing the Security Council, called the destruction of the dam "a terrorist act" by Russia that "aims at causing as many civilian casualties and as much destruction as possible."

A few countries directly accused Russia of destroying the dam, including Albania, Latvia and Poland.

But Ukraine's most powerful allies on the Security Council, including the United States and Britain, stopped short of accusing Moscow. They focused their comments on the human suffering in the Kherson region, where flooding caused by the dam's collapse has forced people to flee their homes. Ukrainian officials estimate there are about 16,000 people on the Ukrainian-controlled western bank and another 25,000 people on the Russian-controlled eastern bank who are in the path of flooding.

"This act has put thousands of civilians in danger and is causing severe environmental damage to the surrounding area," James Kariuki, Britain's deputy ambassador to the U.N., said. "Flooding threatens to contaminate water supplies and vital natural habitats. Vast swathes of agricultural land and electricity supplies are also at risk. And this in turn threatens food production and the international food trade."

The French ambassador, Nicolas de Rivière, noted the loss of the dam also affects the safety of the Zaporizhzhia Nuclear Power Plant, which uses the reservoir created by the dam for cooling fuel and now must rely on a backup cooling pond. "The destruction of the dam further increases the threats to the safety and security systems of the Zaporizhzhia power plant," he said.

Laurence Tan

Satellite images provided by Maxar Technologies, one in color and one in black and white, show port facilities and an industrial area in the city of Kherson before and after they were flooded on Tuesday when the Kakhovka dam collapsed.

Andrew E. Kramer

KRYVIY RIH, Ukraine — The loss of a large reservoir above a blown-up dam in southern Ukraine poses no immediate risk of a meltdown at Europe's largest nuclear power plant, even though the plant uses the reservoir water for cooling, the head of Ukraine's state-owned nuclear company said Tuesday in an interview.

That's because the Zaporizhzhia Nuclear Power Plant was designed to let engineers shut down its six nuclear reactors even in the event the Kakhovka dam were to collapse and the reservoir to drain, as is now happening. The plant can still draw water from a large cooling pond on the grounds.

"There are design conditions which were calculated for this event," Petro Kotin, the president of Energoatom, said. "There are no dire consequences that are critical for the Zaporizhzhia Nuclear Power Plant."

Mr. Kotin said the plant can be kept safe after losing the reservoir as its primary source of cooling water if the Russian force occupying the site manages it correctly.

"The possibility of a radiation release now depends on their actions, what they have on their minds, what they do with the nuclear materials in their possession," Mr. Kotin said.

All six of the plant's reactors are currently shut down but still require water to circulate in their cores to dissipate residual heat from nuclear reactions. Each reactor also needs water for a cooling pond for spent fuel.

Supplying cooling water at the plant now, and perhaps for years to come, will depend on maintaining water levels in the site's cooling pond, which used to be fed by the reservoir.

The plant has wells that can be drawn on to refill the pond. As an additional safety measure put into place after the Fukushima nuclear accident in Japan in 2011, it also has six truck-mounted pumps that can be driven to a water source — such as the Dnipro River running through the bed of the drained reservoir — and pump cooling water through pipes back to the plant.

These trucks were originally envisioned as backups for individual reactors but could be used to refill the plant's cooling pond, Mr. Kotin said.

The plant's operating manuals say the reactors can be shut down safely, the fuel inside the cores can be cooled and water can be circulated in the spent-fuel cooling pools for 12 years drawing only on the large on-site pond, Mr. Kotin said. This is longer than three to eight years required to cool fuel after a reactor shutdown so it can be safely transferred to dry storage, he said.

Without a reliable source of additional cooling water, he added, the reactors cannot be restarted. And if the Russian occupying force restarts a reactor, he said, the additional heat will cause cooling water to evaporate more quickly and the water levels in the pond could drop.

One big worry for Ukrainian officials is that the Russians might sabotage the plant or damage the reactors to accomplish some war aim, Mr. Kotin said. If it is established the Russians were responsible for blowing up the dam, as Ukraine claims, it would only reinforce those fears.

"They threaten the whole world with their presence," Mr. Kotin said of the Russian occupation force at the site. To secure the site, he said, "we need to liberate the plant, get them out and put our staff in as the legal operator."

Maria Varenikovacontributed reporting.

James Glanz, Marc Santora, Riley Mellen and Richard Pérez-Peña

A deliberate explosion inside the Kakhovka dam, on the front line of the war in Ukraine, most likely caused its collapse on Tuesday, according to engineering and munitions experts, who said that structural failure or an attack from outside the dam were possible but less plausible explanations.

Ukrainian officials blamed Russia for the failure, noting that Moscow's military forces — which have repeatedly struck Ukrainian infrastructure since invading last year — controlled the dam spanning the Dnipro River, putting them in a position to detonate explosives from within.

"It was mined by the Russian occupiers. And they blew it up," President Volodymyr Zelensky of Ukraine wrote on social media.

Russian officials, in turn, blamed Ukraine, but did not elaborate on how that might have been done.

"We are talking about deliberate sabotage by the Ukrainian side," Dmitry S. Peskov, the Kremlin spokesman, told reporters.

Experts cautioned that the available evidence was very limited, but they said that an internal explosion was the likeliest reason for destruction of the dam, a massive structure of steel-reinforced concrete, completed in 1956. And local residents reported on social media that they heard a huge explosion around the time the dam was breached, at 2:50 a.m.

A blast in an enclosed space, with all of its energy applied against the structure around it, would do the most damage — and even then, they said, it would require hundreds of pounds of explosives, at least, to breach the damn. An external detonation by a bomb or missile would exert only a fraction of its force against the dam, and would require an explosive many times larger to achieve a similar effect.

The Kakhovka dam had been damaged repeatedly in more than a year amid heavy fighting, and each side has accused the other of shelling it. The Russians captured it last year when they advanced to the Dnipro and beyond, but months later the Ukrainians pushed Russian forces off the west bank, turning the river — and the dam — into part of the boundary between the warring sides. The Russians held onto the dam itself.

It is not clear, though, that the kind of damage the dam had sustained was anywhere near enough to cause it to break down.

"Dams do fail; it's absolutely possible," said Gregory B. Baecher, a professor of engineering at the University of Maryland and member of the National Academy of Engineering, who has studied dam failures. But, he added, "I look at this and say, ‘Gosh, this looks suspicious.’"

Since early May, water has risen above the gates and crested over the top of the dam. Satellite images taken last week showed more of the roadway gone. When dams collapse because of unusually heavy water flows, the failures normally would start on the earthen part of the dam, on either bank, Mr. Baecher said.

But photos and videos show that the Kakhovka dam was first breached in the middle, next to the power plant adjoining the Russian-held bank. Both ends of the dam appeared to be intact at first, though as the day went on, more and more of it collapsed.

A combination of damaged sluice gates and high water might tear away a few gates, but would not be expected to rip apart so much of the dam, Mr. Baecher said.

James C. McKinley Jr.

The National Police of Ukraine said on Tuesday night that at least 23 towns and villages had been flooded, and the water level in the Dnipro River had risen by nearly 11 feet in the city of Kherson since the dam burst. By 9 p.m. local time, 1,366 people had been evacuated from flooded zones, the police said. Many were rescued by boat. There were no casualties.

Kwame Opam

President Volodymyr Zelensky of Ukraine argued on Twitter that Russia was behind the collapse of the Kakhovka dam, pointing out that Moscow controlled the dam and saying it was impossible to destroy it from the outside with shelling. "It was mined by the Russian occupiers," he wrote. "And they blew it up." He called the resulting flood the largest man-made disaster in Europe in decades. "Russia has detonated a bomb of mass environmental destruction," he said.

Tyler Hicks

Evacuations were going on in other places besides the flooded banks of the Dnipro River. Anna Vasilivana Rudenko, 69, was evacuated from her apartment in Toretsk, in the eastern Donetsk region, by Vostok SOS, a volunteer organization that rescues civilians from conflict zones. In the city, an apartment building was damaged by bombing from a Russian aircraft.

Aurelien Breeden

France said on Tuesday that it stood "ready to assist the Ukrainian authorities in dealing with the consequences" of the destroyed dam. "The partial destruction of the Kakhovka dam last night is a particularly serious act," the French foreign ministry said in a statement. "It illustrates once again the tragic consequences of an aggression for which Russia bears sole responsibility."

Kwame Opam

Ursula von der Leyen, the president of the European Commission, denounced Russia on Twitter for what she called "war crimes committed in Ukraine," saying that the destruction of the Kakhovka dam put thousands of people in the Kherson region at risk. In a followup tweet, she added that the E.U. is coordinating with member states to deliver dirt water pumps, fire hoses, mobile water purification stations and boats to Ukraine.

Kwame Opam

Oleksandr Prokudin, the head of the Kherson regional military administration, said that 1,364 people had been evacuated from the flooded areas and that 1,335 houses had flooded.

Eric Schmitt

Some military analysts struck a cautionary note about trying to assign blame for the destruction of the dam with limited information. "It's too early to tell whether this is a deliberate act by Russia or the result of negligence and prior damage inflicted to the dam," said Michael Kofman, the director of Russian studies at CNA, a research institute in Arlington, Va. Mr. Kofman noted the disaster "ultimately benefits nobody."

Aishvarya Kavi

John Kirby, a spokesman for the National Security Council, said the United States has been monitoring the effects of the destruction of the Kakhovka dam but that he could not confirm news reports that Russia was responsible. "We are working with the Ukrainians to gather more information," Kirby said. "We know there are casualties, including likely many deaths, though these are early reports and we cannot quantify them."

Aishvarya Kavi

Asked if the U.S. would consider the destruction to be a war crime, Kirby said it was too early to determine. But he stressed that Russia was illegally occupying the dam at the time of the explosion. "It's very clear that the deliberate destruction of civilian infrastructure is not allowed by the laws of war," he said.

Matthew Mpoke Bigg

A large pond next to the Kakhovka reservoir contains enough water to cool the reactors at the Zaporizhzhia Nuclear Power Plant for "some months," lessening the immediate risk posed to the plant when the reservoir's dam was destroyed on Tuesday, the International Atomic Energy Agency said in a statement. "It is therefore vital that this cooling pond remains intact," the statement said. "Nothing must be done to potentially undermine its integrity."

Matthew Mpoke Bigg

A team of U.N. inspectors based at the nuclear plant will continue to monitor the situation and the agency's director, Rafael Mariano Grossi, plans to visit the nuclear power plant next week, the statement said.

Farnaz Fassihi

The United Nations Security Council is holding an emergency meeting on Ukraine today at 4 p.m. and diplomats will be briefed by senior U.N. officials on the situation on the ground. The U.N. said the scope of damages from the destruction of the dam is under assessment but it has dispatched teams of humanitarian workers to assist the evacuees.

Farnaz Fassihi

The U.N. secretary general, Antonio Guterres, decried the destruction of the Kakhovka hydroelectric dam, calling it a "monumental humanitarian, economic and ecological catastrophe" and "yet another example of the horrific price of war on people."

Max Bearak

Because of the war's toll on Ukraine's economy, electricity usage is far lower than it once was — so much so that Ukraine exported small amounts of electricity from its grid to nearby parts of Europe last summer.

John Yoon and Kwame Opam

Dnipro

River

Kryvyi Rih

Zaporizhzhia

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Nikopol

Kakhovka

reservoir

Zaporizhzhia nuclear

power plant

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Areas

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Kyiv

Kyiv

UKRAINE

UKRAINE

Kakhovka dam and

power plant

Nova

Kakhovka

Kherson

Detail area

Detail area

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River

Kyiv

UKRAINE

Zaporizhzhia

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reservoir

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Zaporizhzhia nuclear

power plant

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evacuated

Kakhovka dam and

power plant

Kherson

Nova

Kakhovka

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Zaporizhzhia

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Zaporizhzhia nuclear

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Kyiv

Kakhovka dam and

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Sources: Institute for the Study of War with American Enterprise Institute's Critical Threats Project; Google Maps.

A critical dam on the Dnipro River in southern Ukraine broke overnight on Tuesday, endangering tens of thousands of people who live downstream. It was not clear what caused the breach. Ukraine blamed Russia, saying that there had been an explosion in an engine room. Russia said that Ukrainian forces had carried out sabotage.

Ukrainian officials began evacuating people in the Kherson region on Tuesday as huge volumes of water gushed from the dam's reservoir. Floodwaters were expected to rise through the night and peak on Wednesday morning, the head of Ukrhydroenergo, a state-owned hydropower company, said in an interview.

The U.N. secretary general, António Guterres, decried the destruction of the Kakhovka hydroelectric dam, calling it a "monumental humanitarian, economic and ecological catastrophe" and "yet another example of the horrific price of war on people."

Videos of the dam, in the town of Nova Kakhovka, reviewed by The New York Times do not reveal what caused the destruction. But they do show water flowing freely through the dam, indicating severe damage.

A day before the disaster, American and Russian officials said a planned Ukrainian counteroffensive appeared to have begun east of the Dnipro River in the Donetsk region. The flooding could divert both sides’ attention and resources from that counteroffensive.

Located near the front line of the war in the southern Kherson region, the dam and nearby infrastructure have been damaged by shelling throughout the war. The area including the dam and the adjacent hydroelectric plant has been occupied by Russian forces since last year. The Ukrainians now say the power plant cannot be restored.

Engineering and munitions experts said that an internal explosion was the most likely cause of the destruction.

On Tuesday, Russia and Ukraine blamed each other for the destruction, without offering evidence.

President Volodymyr Zelensky of Ukraine blamed "Russian terrorists," while the Kremlin's spokesman, Dmitri S. Peskov, blamed Ukrainian forces, describing what happened as sabotage.

"They decided that now, in this way, they will be able to stop the counteroffensive of Ukrainian forces," Natalia Humeniuk, a spokeswoman for Ukraine's southern command, told Radio Svoboda on Tuesday.

Sergei K. Shoigu, Russia's defense minister, accused Ukraine of destroying the dam, saying Kyiv wanted to move forces and equipment defending Kherson to other parts of the front to help with its counteroffensive.

Security of the dam, a vital source of water and power, has been a continuing concern during the war, with both sides accusing the other of plotting to destroy it.

John F. Kirby, a spokesman for the National Security Council, said that the United States had been monitoring the effects of the destruction of the Kakhovka dam but that he could not confirm news reports that Russia was responsible.

Communities along the waterway are at risk of being flooded and washed away. More than 40,000 people could be in the path of flooding on both the Russian- and Ukrainian-controlled sides of the river, according to the deputy prosecutor general of Ukraine.

In telephone interviews arranged by a group distributing humanitarian aid in Antonivka, residents described how they had watched as rising waters crept from house to house. They kept their distance from the river bank, where Russian snipers on the opposite side have in the past fired at residents, they said.

The eastern bank of the river, south of the dam, is controlled by Russian forces.

The damage threatens to disrupt vital services provided by the dam's reservoir. It will cause a severe shortage of drinking water in the Dnipro, Zaporizhzhia and Kherson regions, said Ihor Syrota, the hydropower company chief.

Flooding could also wash mines from their original positions into previously safe areas, posing a fatal risk to civilians returning to their homes. Russian officials say the destruction could pose problems for a canal supplying water to Crimea.

It also provides water for the cooling of reactors and spent fuel at the nearby Zaporizhzhia Nuclear Power Plant, but Ukrainian officials and the U.N.'s nuclear watchdog said Tuesday that the facility was not at immediate risk of meltdown as a result of the damage to the dam.

Towns continued to disappear under the water flowing from the reservoir early Wednesday, forcing more residents to evacuate. In Nova Kakhovka, where the dam is, the city hall and Palace of Culture were inundated.

Floodwaters swept even areas miles downriver. Residents in one village could be seen wading through their front yards, rescuing pets and belongings. Roads were submerged, putting people trying to escape at risk of being stranded.

The magnitude of the flooding's impact is difficult to gauge as waters are still rising. Reliable information is hard to come by, especially from the Russian-held areas east of the Dnipro River. Shelling has continued as residents escape their flooded homes.