Russia

Dec 31, 2023

Ukraine and Russia blamed each other for the attack on the Russian-held facility, which came a day after U.S. officials said it appeared a Ukrainian counteroffensive had begun. Hundreds of residents are evacuating under the threat of flooding.

Areas of confirmed flooding

5 miles

HELD BY

UKRAINE

UKRAINE

Detail area

Damaged grain

elevator

Mykolaivka

Kakhovka

reservoir

Burhunka

Olhivka

Lvove

Tianhynka

Kakhovka dam

Odradokam'yanka

Tokarivka

Poniativka

Ivanivka

Korsunka

Nova Kakhovka

Flooded areas

on both riverbanks

Krynky

Dnipriany

Mykilske

Kozachi Laheri

Sadove

Center of

Nova Kakhovka

submerged

Pishchane

Prydniprovske

Flooding reported in

multiple villages

downstream

of the dam

Antonivka

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

RUSSIA

Stara Zbur’ivka

Areas of confirmed flooding

5 miles

UKRAINE

HELD BY

UKRAINE

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

RUSSIA

Stara Zbur’ivka

Areas of confirmed flooding

N

Kakhovka

reservoir

UKRAINE

Detail area

Kakhovka

dam

Center of

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

Zbur’ivka

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

Follow live news updates on the Russia-Ukraine war.

Haley Willis, Andrew E. Kramer and Victoria Kim

A critical dam along the front line in southern Ukraine was destroyed on Tuesday, sending cascades of water pouring through the breach and putting thousands of people downstream at risk. Ukraine and Russia each accused the other of blowing up the dam, which held back a body of water the size of the Great Salt Lake in Utah.

It was not immediately clear who was responsible for the destruction of the Kakhovka dam and electric plant, which lies along the Dnipro River and is held by Russian forces. As water levels rose south of the dam, residents in the town of Antonivka, about 40 miles downstream, described watching in horror as roiling floodwaters swept past carrying trees and debris from washed-out houses.

Ukrainian emergency crews rushed to evacuate the most vulnerable on the western side of the river, while conservationists warned that a huge and long-lasting environmental disaster was unfolding.

It was more difficult to assess what was happening on the eastern bank of the river south of the dam. But more than 40,000 people could be in the path of the flooding on both Ukrainian- and Russian-controlled territory, the deputy prosecutor general of Ukraine, Viktoriya Lytvynova, said.

President Volodymyr Zelensky blamed "Russian terrorists," while the Kremlin's spokesman, Dmitri S. Peskov, said Ukrainian forces carried out a "sabotage" attack.

The disaster came one day after American and Russian officials said a planned Ukrainian counteroffensive might have begun east of the Dnipro in the Donetsk region. Though the dam is far from that fighting, its destruction could divert both sides’ resources from the counteroffensive.

The dam creates a reservoir that supplies water for drinking and agriculture. It also provides water to cool reactors and spent fuel at the Zaporizhzhia Nuclear Power Plant, though the United Nations’ nuclear watchdog, the International Atomic Energy Agency, said there was "no immediate nuclear safety risk." The group said, however, that it was closely monitoring the situation.

Security of the dam, the second largest on the Dnipro, had been a continuing concern during the war, with both sides accusing the other of plotting to destroy it.

Here are other developments:

This is what we know so far about the Ukraine dam disaster.

Videos and images on social media showed flooding already underway in communities downstream from the Kakhovka dam, and streets filling with rising water. In Nova Kakhovka, the city under Russian control that lies immediately downstream of the dam, the Palace of Culture and administrative center were swamped.

An energy official said floodwaters across southern Ukraine caused by the destruction of the Kakhovka dam are expected to continue to rise through the night and peak on Wednesday morning.

In Mykolaiv, an emergency train collected people fleeing the rising waters in Kherson, about 40 miles to the east. Humanitarian groups were just starting to arrive to provide support for those forced from their homes by flooding.

Russian officials said the destruction of the dam potentially poses problems for a canal supplying water to Crimea that has for years been a point of geopolitical tension between Kyiv and Moscow.

Marc Santora, Maria Varenikova and Anna Lukinova contributed reporting.

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," Dmitri 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, an enormous 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 dam. 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 in a bulletin on the Telegram messenger app. Many were rescued by boat. The bulletin said the police had no information yet on casualties.

Kwame Opam

President Volodymyr Zelensky of Ukraine argued forcefully on Twitter that Russia was behind the collapse of the Kakhovka dam on Tuesday, pointing out that Moscow controlled the dam and saying it was impossible to destroy the massive structure 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.

Marc Santora and Evelina Riabenko

The early morning explosion that woke Oksana Alfiorova from her sleep seemed normal enough, at least for wartime Kherson.

Ms. Alfiorova, who is 57, lived through nine months of Russian occupation — "really scary" — and since then, nearly as long under the constant shelling of the Russian forces that set up camp across the Dnipro River after they were driven out of the city.

But even for Kherson, she soon realized Tuesday morning, things were far from normal.

Water was filling the streets of her low-lying neighborhood — and rising quickly. A dam had been destroyed, and soon the power went out, the gas stopped working and the water supply to her apartment stopped flowing.

So Ms. Alfiorova did something she had long resisted despite all the hardships of the past year and a half: She fled. She boarded an evacuation train from Kherson to Mykolaiv, about 40 miles to the west, stepping out onto Platform 1, homeless for the first time in her life.

"I had no choice," she said.

Many of her neighbors and friends, however, decided to take their chances and stay, and on the train meant to take people to safety, there were only 43 passengers, among them several children. Most of the 10 cars were empty.

Ms. Alfiorova said many people she knew had decided to move to higher ground to stay with friends and family or to ride out the floods in apartments on high floors.

"I have a neighbor on the third floor and she has three dogs," she said. "She is not going to leave her home."

She herself lives on the fourth floor of the nine-story building, and for her, the flooding was one hardship too many, though it is the just latest sorrow for a city that was home to 290,000 people before Russia invaded last year.

Ms. Alfiorova, a sociologist, recalled the grim months of Russian occupation, when she had little money or food. Soldiers menaced civilians, seeking out those with pro-Ukrainian sympathies, looting homes and businesses, and failing to deliver even the most basic services to people.

The threat did not fully lift after Ukrainian forces recaptured Kherson in November and the Russians took to shelling the city from afar. Ms. Alfiorova became so used to it that she learned to measure the danger by the sounds in the air.

"If I hear a whistle, it can be quite far," she said. "If it is whistling I know it is not for my soul. But when it is a rumbling sound, you realize that it will land quite close."

In March, she said, a shell exploded so close that she thought for a moment it could be the end. But she survived.

On Tuesday, when explosions boomed once again around 4 a.m. she figured it was just the usual Kherson wake-up call. It was not. "The neighbors were screaming," she said.

As the streets disappeared under a coursing tide of water, police cars began patrolling with loudspeakers to warn of the growing danger. Evacuate, residents were urged.

"I checked the Telegram channels, talked to neighbors and friends and decided to go," Ms. Alfiorova said. She and her son, Oleh, 23, raced to gather important documents, a few cherished possessions and her two cats, Biusia and Miusia, whom she placed in cardboard pet carriers.

But when they tried to make it out of their neighborhood, the shelling resumed, forcing them to take cover in a basement. Only when it subsided could they make their way to the train station.

"As we were leaving, we realized we forgot all of our money," Ms. Alfiorova said. But there were teams of volunteers from a host of aid agencies at the train station to help her.

She has checked back with friends who stayed behind and believes she made the only decision she could, however hard. "The level of the water is so high now, people can swim," she said.

Similar scenes were described in Antonivka, about 40 miles downstream from the destroyed dam.

One resident of the town, Hanna Zarudnia, 69, said she had spent the night in a basement bunker because of intense shelling. "About 10 houses were damaged," she said. "Roofs were destroyed."

Then a new horror took shape.

"Antonivka was surrounded by water from all sides, we were on an island," she said. "I have pictures, videos: roads, a stadium, a school were flooded, everything came under water."

Ukraine and Russia have each accused the other of blowing up the dam, a critical structure whose breach has put thousands of people downstream at risk.

Ms. Zarudnia scoffed at the notion that Ukraine blew up its own dam, and recalled that similar claims were made about attacks in Kherson, where she once lived under occupation. "I was a witness to that," she said.

She has no doubt who was bombing her home week after week back then, she said, and none about who blew up the dam now.

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," lessing 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.

Isabella Kwai and Andrew E. Kramer

The destruction of the Kakhovka dam could increases the risk posed by land mines, as the flood exposes underground mines planted on the banks of the Dnipro River by Russian and Ukrainian forces and washes them downstream.

The United Nations warned on Tuesday that the floods might move land mines and explosives, creating new hazards to areas that were previously deemed safe.

The HALO Trust, a British American charity that clears land mines, said that it has been conducting operations in areas now affected by the flooding. The group has been clearing mines that were planted by Russian troops to prevent Ukrainians from crossing the Inhulets River, a front line last year.

"These mines are now posing a fatal risk to civilians who are returning to their homes or use the fertile banks to graze their animals, cultivate crops and fish," said Jasmine Dann, the charity's location manager for the Mykolaiv region.

Ms. Dann said that the group had already seen a 21-inch rise in the river level on Tuesday since the flooding began. With many mines sitting close to the surface, the force of the current could wash them away or cause explosions while they are in the water, she added.

The teams regularly cross the river to clear minefields, she added, and more than 460 mines had been discovered near riverbanks. If river levels rose significantly, their teams would be cut off from access.

Daria Shulzik, 38, who lives in a town downstream from the dam, said she worried that the waters would dislodge land mines and spread them about.

The Russian military, she said, had created a disaster in her region. "I don't know why they started this war, and why they carry on," she said, adding: "Agriculture will suffer, and the Black Sea will suffer because all this is flowing into the sea," she 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.

Paul Sonne

The destruction of the Kakhovka dam potentially poses problems for a canal supplying water to Crimea that has for years been a point of geopolitical tension between Kyiv and Moscow, Russian officials warned on Tuesday.

The canal, the Northern Crimean Canal, runs approximately 250 miles from the reservoir above the dam down to Crimea, the Black Sea peninsula that Russia annexed illegally in 2014.

For years, it served as Crimea's main water resource, but shortly after the annexation, Ukraine blocked the flow of water. Russia restored it after invading last year and occupying the territory around the canal.

The Kremlin's spokesman, Dmitri S. Peskov, said in a briefing on Tuesday that water levels in the reservoir were falling as a result of the dam's destruction, reducing supply to the canal. Only a small portion of the canal's water supply is used for drinking water. Most of it is used for agricultural purposes in Crimea.

Sergei Aksyonov, the Kremlin-installed leader of Crimea, said on Tuesday that there was a risk of the water in the canal becoming shallow.

Writing on the Telegram messaging app, Mr. Aksyonov said that 40 million cubic meters of water remained in the canal and that work was being done to minimize losses. He said reservoirs in Crimea were 80 percent full, adding that there was sufficient drinking water for the peninsula's residents.

"In the coming days, the situation will be clear, as well as the possible risks," Mr. Aksyonov wrote.

Christoph Koettl

A satellite image captured Tuesday morning shows the destruction of the Kakhovka dam in the clearest detail yet, including how quickly the unleashed water breached and partially submerged the dam and its immediate surroundings.

An earlier satellite image of the same dam, taken two days earlier, shows it intact.

Tuesday's image shows a breach at the dam in three locations. About 200 yards of the dam's central area have been destroyed, and a structure at the hydroelectric power plant sitting atop the dam is split in half. A drone video taken earlier in the day showed part of the southern end of the dam still intact. However, only a few hours later, that area was underwater, according to the satellite image.

Floodwaters have reached at least two miles downstream of the dam, where a marina and sports facilities in the town of Nova Kakhovka have disappeared completely under the water, according to the satellite image.

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."

Marc Santora

MYKOLAIV, Ukraine — Floodwaters across southern Ukraine caused by the destruction of the Kakhovka dam are expected to continue to rise through the night and peak on Wednesday morning, the head of Ukraine's hydropower company said in an interview.

The Kakhovka reservoir holds about the same volume as the Great Salt Lake in Utah and if water continues to flow out at the current rate, Ihor Syrota, the head of Ukrhydroenergo, said it would take four to five days to reach "the zero mark."

"We expect the peak to be between tonight and tomorrow morning," he said. "After that, in two days, it will start to decline, and we understand that within 10 days this water will be gone and we will see the consequences of this disaster."

It is impossible to stop the flow of water and the rate is only likely to increase, he said, adding that the dam's electric plant can't be repaired. "The lower part of it has already been washed away," he said.

The loss of the dam will not severely affect the country's energy grid, he said, because the hydroelectric plant, which has been under Russian occupation since March of last year, has not been operating in the power grid since October.

But it will cause a severe shortage of drinking water in the Dnipro, Zaporizhzhia and Kherson regions, he said.

Max Bearak

Though the destruction of the Kakhovka dam and its hydroelectric plant has immediate humanitarian and strategic implications, it will have little bearing on Ukraine's energy grid. Ukraine derives most of its electricity from the three nuclear plants still under its control. Before it was occupied by Russian troops, the Kakhovka plant accounted for around 2 percent of Ukraine's electricity, said Alex Riabchyn, Ukraine's former deputy energy minister.

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.

Matthew Mpoke Bigg

The Kinburn Spit, which lies at the mouth of the Dnipro River and is controlled by Russian forces, could become an island as a result of flooding caused by the destruction of the Kakhovka dam, the spokeswoman for Ukraine's southern forces, Natalia Humeniuk, said on Tuesday. This would "complicate the enemy's logistics," she said. The spit is a target for Ukrainian forces partly because of its proximity to the Crimea region, which was illegally annexed by Russia in 2014.

Dnipro River

Ukraine

Kherson

Kakhovka dam

Sea of

Azov

Kinburn Spit

Crimea

Russia

Kyiv

Black Sea

UKRAINE

Kinburn Spit

100 miles

By The New York Times

Matthew Mpoke Bigg

If Ukraine gained control of the Spit, it would gain access to the land bridge east of the Dnipro River that is controlled by Russian forces. It would also make it easier to mount any future attack on Crimea. The two sides have traded fire across the water north of the Kinburn Spit since November, when Ukraine retook the city of Kherson.

Isabella Kwai

Flooding from the destroyed Kakhovka dam poses a threat to a diverse array of wildlife and ecosystems that call its network of estuaries, wetlands and marshes home.

Experts on Tuesday were still waiting to understand the scale of the disaster, with the flooding expected to intensify as the waters from the Kakhovka reservoir continue to flow. But they expressed concern about the potential for industrial pollution and the flooding of nearby nature conservation areas.

"It will have a series of acute and also long-term environment effects," said Doug Weir, the research and policy director at the Conflict and Environment Observatory, a nonprofit organization based in Britain. "It's going to have an enormous legacy."

Around the dam itself, species like fish could be spawning in the shallows, Mr. Weir said, adding, "The sudden drop in water level is going to expose those areas and impact habitats." The large volume of water rushing down the river could also damage fragile sand banks, reed beds and other ecosystems along the river.

The Dnipro River and its surrounding land were already home to an array of nature reserves. There is Oleshky Sands National Nature Park, Europe's second-largest expanse of sand, and the Black Sea Biosphere, a UNESCO-designated reserve of wetlands and marshes. And further downstream, there is the Nizhnyodniprovskyi National Nature Park, also known as the Lower Sula National Park, a protected area home to a vast array of flora and fauna, among them endangered plants and rare birds.

Concerns were also heightened over industrial pollution, with the Ukrainian government saying that 150 tons of machine oil had leaked into the Dnipro River, and that 300 more tons were at risk of seeping into the waterway. That could pose a toxic catastrophe to the river's fish, which had already been decimated by the effects of the war.

Rising water levels could also lead to leaks from fuel stations, septic tanks and industrial sites around the shipyards of Kherson. "All these things can become point sources of pollution if they are inundated, which looks likely to be the case," Mr. Weir said.

An earlier version of this article misspelled the name of a national park in Ukraine. It is Oleshky Sands National Nature Park, not Oleshy Sands National Nature Park.

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Matthew Mpoke Bigg

The rupture of the Kakhovka dam on the Dnipro River in southern Ukraine will have far-reaching consequences both downstream and upstream.

Here is a look at some of the places that are immediately threatened.

The authorities have ordered residents to leave the city, which lies about 37 miles southwest of the dam. In November, Ukrainian forces recaptured Kherson on the west bank of the river. It was a significant victory for Ukraine. Since then, however, the city and the surrounding area on the river's western side have been repeatedly shelled by Russian forces. Many civilians have been killed, and the resumption of normal life has been all but impossible.

Downstream of the dam, toward the Black Sea basin, lie smaller rivers and islands, as well as towns and fishing villages on both sides of the river. These include the town of Oleshky and the Oleshky Sands National Nature Park on the eastern side. Residents have been ordered to evacuate the area, which includes large tracts of rich, irrigated agricultural land. The Ukrainian authorities have said that Russian forces mined the river's east bank to hinder their forces from crossing.

The dam's destruction is draining water into the Black Sea from the Kakhovka Reservoir, a body of water that is 10 miles wide in places. There are a string of villages on the reservoir's banks. Nikopol, on the western bank, is the largest city. It has been repeatedly shelled by Russian forces stationed on the river's eastern bank. Ukraine holds the western side of the river, while Russian forces control part of the eastern side.

The plant, the largest in Europe, is the most critical infrastructure on the reservoir. It sits on the east bank of the river, near the city of Enerhodar and draws water from the reservoir to cool its six reactors. Both Russia and Ukraine have for months been building up their forces along a front line east of the reservoir to prepare for a Ukrainian counteroffensive. The front line in the Zaporizhzhia region begins around 30 miles northeast of Enerhodar.

Haley Willis

Videos and photographs verified by The New York Times illustrated the far-reaching impact after the destruction early Tuesday of a critical dam and hydroelectric power plant in southern Ukraine.

Footage from Nova Kakhovka, the city under Russian control that lies immediately downstream of the dam, shows the area surrounding the Palace of Culture and administrative center entirely flooded. A soccer field in the city is fully submerged. Across the river in the town of Kozats’ke, video shows a grain storage and transportation terminal also flooded.

More than 40 miles downstream of the dam, another video captures the scale of the threat to islands in the Dnipro River. Homes on the eastern tip of Potemkin Island appear to be almost entirely underwater.

That island lies just southwest of the city of Kherson, where flooding had also begun to creep into the streets on Tuesday morning. Video shows rising water levels at the city's Slavy Park, with smoke rising in the distance.

Paul Sonne

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. He suggested that widening the river downstream from the dam would make it easier for Ukraine to defend Kherson with fewer forces and weapons. Ukrainian forces have said Russian forces exploded the dam, in part to prevent Ukrainian troops from crossing the river downstream.

Matthew Mpoke Bigg and Andrew E. Kramer

The Zaporizhzhia Nuclear Power Plant in southern Ukraine, which relies on the Kakhovka reservoir to cool its reactors, is not at immediate risk of meltdown as a result of an attack on the dam downstream of the facility on Tuesday, the U.N.'s nuclear watchdog, Ukrainian officials and a nuclear expert said.

A large pond next to the reservoir contains enough water to cool the plant's reactors for "some months," the International Atomic Energy Agency said. "It is therefore vital that this cooling pond remains intact," it said in a statement. "Nothing must be done to potentially undermine its integrity."

Five of the six reactors at the plant, which is the largest civilian nuclear facility in Europe, have been shutdown for months, meaning they require a relatively small amount of water. The sixth reactor is cooled with water from the large on-site pond fed from the gushing reservoir, but the pond itself is full and secure, said Ulrich Kühn, a nuclear expert at the University of Hamburg and the Carnegie Endowment for International Peace.

"The reservoir will lose a lot of water due to the damaged dam, but right now this is not a big problem for Z.N.P.P.," Mr. Kühn said, using the plant's acronym. "The situation is under control and not critical."

For months, the I.A.E.A.'s director general, Rafael Mariano Grossi, has sounded the alarm about the potential for nuclear catastrophe at the plant. On Tuesday the agency said on Twitter that, while it was "closely monitoring" the situation surrounding the dam, there was "no immediate nuclear safety risk." Mr. Grossi also said that he plans to visit the plant, where his agency has stationed inspectors, next week.

Ukraine's state nuclear company, Energoatom, also said there was no immediate danger, and suggested that the pond had enough water for the foreseeable future.

"The station's cooling pond is full," it said in a post on the Telegram social messaging app. "At 8 a.m. the water level is 16.6 meters, which is sufficient for the station's needs."

Russian forces have occupied the nuclear plant since the early weeks of their full-scale invasion of Ukraine, which began more than 15 months ago. The possibility of a breach in the Kakhovka dam has been an ever-present risk to safety at the facility because of the cooling issue, though shelling has been a more immediate threat.

Water from the Kakhovka reservoir feeds the plant's cooling pond, said Ivan Plachkov, a former energy minister of Ukraine. The facility currently requires 130,000 to 260,000 gallons of water to circulate per hour to maintain safety and critical functions, he said.

Reserve sources of water exist on site but if water is not circulated, the water in the pool could boil and evaporate. That could emerge at some stage as a longer-term risk, but it is not an immediate problem because the pond would most likely only evaporate slowly over time as a result of the sun's heat.

The cooling pond's level "is sufficient for the plant's needs, but over time the water from the pond may evaporate and, in case it couldn't be filled, it wouldn't be possible to operate the plant," said Maria Kurando, a visiting doctoral fellow at the University of Hamburg's Institute for Peace Research and Security Policy.

The American Nuclear Society, an international professional organization, provided additional details on how safety at the plant could be managed in the light of the draining reservoir.

"The nuclear plant has mobile pumping units that can be used to access water from alternative sources," it said in a statement. "The plant also has special floating water intakes which allow the facility to draw water when the reservoir is at low levels."

Moscow has stationed its forces and military equipment at the nuclear facility. Repeated shelling last summer, for which Russia and Ukraine blamed each other, damaged parts of the plant, including an area where spent fuel is stored.

More recently, the plant has been forced to rely on diesel generators at least half a dozen times as workers have switched off external power in response to shelling at power plants elsewhere.

At the same time, the Russian authorities in control of the plant have put pressure on the Ukrainian employees that still work there under occupation to sign contracts with Russia's state nuclear firm, Rosatom. Workers say that they have been detained, beaten and tortured.

Moscow's control of the plant has given it leverage over Ukraine's energy system and it no longer supplies to Ukraine's national grid.

Emma Bubola

James Elder, a spokesman for UNICEF, said the flooding risks were catastrophic. "Children — who have been through so, so much — will be made homeless, and it threatens their access to clean water. This is yet another merciless attack on infrastructure that is vital to the well-being of everyday Ukrainians."

Andrew E. Kramer

Residents of the town of Antonivka looked on in horror at the roiling coffee-colored floodwaters released by the destroyed Kakhovka dam on Tuesday, as they carried trees and debris from washed-out houses downstream.

But even as water levels rose in the town and people waded about in swamped front yards rescuing pets and belongings, Russian artillery shelling was still hitting the town on the outskirts of the southern Ukrainian city of Kherson, which lies about 40 miles downstream from the destroyed dam.

"I heard a boom, and my windows shook," Tatyana Yeroshenko, 32, a teacher of Ukrainian, said in a telephone interview.

"What do they want from us?" she asked. "They want us to be with them, to unite us with Russia. But we aren't happy with that idea. We will never be part of Russia."

The head of the Kherson region military administration, Oleksandr Prokudin, said that in total about 16,000 people lived in towns and villages at risk from flooding in Ukrainian-controlled areas on the west bank of the Dnipro River. It was not immediately clear how many people were at risk in Russian-held areas on the east bank.

The shelling of communities already flooded by the burst dam shed light on the sweeping scale of the disaster of Russia's war in Ukraine, in which tragedies pile on top of tragedies.

The Ukrainian authorities were evacuating people by train and bus on Tuesday. As the floodwaters rose, swamping houses, spilling over farm fields and blocking roads, they also flooded a zoo in the town of Nova Kakhovka, according to the city's mayor, Volodymyr Kovalenko.

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.

In this area of southeastern Ukraine, where the Dnipro River forms the front line, the floodwaters were flowing into towns where tens of thousands of people had already evacuated because of the war. In Antonivka, for example, about 4,000 residents remained before the flooding Tuesday, out of a prewar population of about 13,000, according to Ms. Yeroshenko, who is also a volunteer at the aid group, which had estimated the wartime population.

Ms. Yeroshenko woke up around 5 a.m. to explosions from artillery, a common occurrence in her town, she said. She said she checked her phone for news and saw reports that the Russians had also caused a major flood. "The water is rising," she said later that morning. It had already inundated the town's soccer stadium, she said. As well as the threat to human life, she said the disaster could result in "an ecological catastrophe."

Daria Shulzik, 38, an office manager, said she awoke to an unusual noise from the river that sounded like pouring rain. The water was muddy and flowing past, she said, and there were "a lot of dirt, branches, parts of buildings, fences, cattails from swamps — everything." The flooding was blocking roads, she said.

Ms. Shulzik also worried that the water would dislodge land mines planted in abundance on both banks of the rivers by both Russia and Ukraine's armies and spread them about in the floodwater.

The Russian military, she said, had created a disaster in her region. "I don't know why they started this war, and why they carry on," she said, adding: "agriculture will suffer, and the Black Sea will suffer because all this is flowing into the sea," she said. "Even the fish will suffer now."

Marc Santora

For Ukrainians who have experienced all manner of catastrophe across more than 15 months of war, the rising waters that flooded towns and villages across southern Ukraine on Tuesday were a new and different kind of threat.

Unlike a missile strike that can come without warning and bring devastation in an instant, the surge of water unleashed after an explosion severed a dam on the Dnipro River was a slow moving crisis, unfolding over hours in places where reliable information was already scarce.

In Mykolaiv, the southern port city, an emergency train pulled out of the station to collect people fleeing the rising waters in Kherson, about 40 miles to the east. Humanitarian groups were just starting to arrive to provide support for those forced from their homes by flooding.

Yevhen Chupyna, a Red Cross rescue worker, said that the scale of the disaster had yet to come into focus for many living in areas that might be flooded.

"The situation is difficult emotionally and psychologically," he said as he helped unpack boxes of humanitarian aid. "People don't really know what happened. They have not realized this is a catastrophe."

With communications spotty, he said it was difficult to get accurate information about the state of the flooding. The city of Kherson straddles the Dnipro River, which has become a front line in the war, dividing the warring armies.

The western bank, which is where the majority of Kherson's residents live and work, is controlled by Ukraine, retaken last fall after eight months of Russian occupation. It mostly sits on elevated land but there are some neighborhoods close to the river bank where flooding has already been reported. The eastern bank, controlled by the Russians, is kind of a bayou, with islands and marshes and many country homes accessible only by boat, even before the dam was breached.

Ukrainian officials, citing reports from emergency workers and volunteers, said some neighborhoods near the river were already flooded. Vasyl, 40, a factory worker who lives in Kherson, said in a brief text message that people were trying to evacuate low lying neighborhoods but that Russians were still shelling the area.

"Russians opened mortar fire as people prepared to evacuate from Ostriv," he wrote. "They are terrorizing us."

Alim, who reached out from Kherson via text message, said people in the lower part of the city were in a panic. "Some are moving stuff to the upper floors and roofs of their houses, while others are packing the cars and trying to leave," he wrote.

Buses were being organized to take people from their home to the train station, but only about 30 people were registered to take the first 10-car train as of 12 p.m. local time. Mr. Chupyna said that they have hundreds of beds in Mykolaiv prepared for people who were forced from their homes.

Over 15 months of war, Ukrainian volunteer organizations have become adept at responding quickly to emergencies. But rising waters from a breached dam was a totally new challenge. Olha Napkhanenko, 40, a volunteer with the Serhiy Prytula Charity Foundation, said that her colleagues in the city of Kherson reported only about 5 percent of the city being severely affected as of noon, but that the situation could get worse.

As she prepared snacks for the children who might arrive, the Ukrainian national anthem echoed through the station hall as workers stacked supplies.

"The worst will be on the eastern bank," she said, referring to Russian-occupied territory. "Unfortunately, we can't help them."

Svitlana Sitnik, 52 a volunteer from a different organization, said her aunt was in one of the towns on the east bank occupied by the Russians, Oleshky, and she was in contact with people there via a private Telegram channel. They painted an increasingly dire situation for the civilians there as Russian soldiers continued to patrol the streets and refused to provide assistance as the waters rose

The Russians announced an evacuation plan, people in the city reported, but details were scarce about how it would work.

For now, Ms. Sitnik said, it was neighbors helping neighbors in Oleshky. "Local volunteers are offering to help people get to Crimea," she said.

But internet and cellular service was spotty and even if they could use their phones, she said, people are afraid to use them on the streets for fear of attracting the attention of Russian soldiers. "All the people are exhausted," she said as she shared with a reporter the conversations on the secure Telegram channel on her phone. "They are on the edge. They have no rights."

Monika Pronczuk

The European Union condemns the attack in the "strongest possible terms," and stands ready to provide humanitarian assistance to Ukraine, Josep Borrell Fontelles, the bloc's top diplomat, said in a statement. The attack represents "a new dimension of Russian atrocities," Borrell added, and may be a violation of international humanitarian law, for which "all commanders, perpetrators and accomplices" will be held accountable.

Matthew Mpoke Bigg

Russian forces shelled the southern Ukrainian region of Kherson on Tuesday and wounded two police officers while the area was being evacuated, Ukraine's minister of internal affairs, Ihor Klymenko, said on national television. Russian forces have shelled the river's western side regularly since they withdrew from the city of Kherson in November.

Matthew Mpoke Bigg

The dam's destruction also increases the risk posed by land mines, Klymenko said, referring to the prospect that flooding could wash mines from their original positions. The Ukrainian authorities have previously accused Russia of mining the eastern bank of the Dnipro River to impede any attempt by Ukrainian forces to cross the river as part of a counteroffensive.

Marc Santora

Alim, who reached out from Kherson via text message, said people in the Kindiyka district, which is in the lower part of the city, were in a panic. "Some are moving stuff to the upper floors and roofs of their houses, while others are packing their cars and trying to leave," he wrote. "The road to the northeast of Kherson is flooded in several places," he wrote, adding that residents of the villages that are flooded might already be stranded.

Paul Sonne and Marc Santora

It was not clear who was responsible for the destruction of the Kakhovka dam on Tuesday, but Kyiv and Moscow, without offering evidence, quickly blamed each other for the torrent of water that was putting thousands of people at risk.

President Volodymyr Zelensky blamed "Russian terrorists" and Ukrainian officials said Russian forces had caused an explosion at the Russian-held facility. The Kremlin's spokesman, Dmitry S. Peskov, blamed the destruction of the dam on Ukrainian forces, describing it as a "sabotage" attack that could result in "very severe consequences" for local residents and the environment. Russia's Investigative Committee said it had launched a criminal investigation.

The security of the dam, the second largest of the cascade of dams on the Dnipro River and a vital source of water and power, has been a continuing concern during the war in Ukraine, with both sides accusing the other of plotting to destroy it.

Mr. Peskov said one of the reasons Ukraine would have for attacking the dam would be to deprive Crimea of water. The reservoir above the destroyed dam connects to a canal supplying water to the Crimean peninsula, which Russia annexed illegally in 2014.

Mr. Peskov denied accusations by Ukrainian officials that Russian forces had blown up the dam.

"All responsibility for all the consequences should rest with the Kyiv regime," he said.

Ukraine's hydropower company, Ukrhydroenergo, said the damage at the dam was caused by an explosion inside the engine room, which is under Russian control. The power plant, it said, "cannot be restored."

Mr. Zelensky condemned the destruction of the dam as an act of terrorism and blamed Russian forces, which he vowed to push out of Ukraine. Ukraine has called for an urgent meeting of the U.N. Security Council to discuss the attack, the ministry of foreign affairs said in a statement.