As officials scramble to evacuate thousands, experts assess the environmental toll and both sides trade blame, one key question hung over the flooded fields of Kherson: Who, if anyone, might stand to gain from this stunning turn in the war?
NBC News looks at what the disaster could mean for the conflict.
What could be in it for the Kremlin?
Ukraine immediately pointed the finger at Russia, whose forces controlled the dam and parts of the surrounding region.
The incident came less than 48 hours after Moscow claimed that Kyiv had launched its long-anticipated counteroffensive, and Ukrainian officials and Western military analysts said the timing may not be a coincidence.
The Kherson region, annexed and partly occupied by Russia, has long been seen as a likely target for Kyiv, almost seven months after it liberated the region’s capital in an offensive blitz.
That pushed Russian troops into an embarrassing retreat across the Dnieper River, which now bisects the front lines, while Moscow kept control of the Soviet-era dam. Ukraine warned previously that Russia might be planning to blow up the dam, while Moscow said the same about Kyiv.
“Russia would stand to gain most,” said Christopher Tuck, an expert in conflict and security at King’s College London. It “would only have made military sense to Ukraine while Russia was on the western side, which it now isn’t, and it never made political sense.”
The increased intensity of Ukrainian attacks across the front lines this week may hint that the counteroffensive has begun, but the breadth of the battlefield will now be reduced. That, analysts said, benefits Russia.
Blowing up the dam would make any Ukrainian attempt to cross the river with a significant force — an already difficult task — impossible, said Michael A. Horowitz, a geopolitical and security analyst who is the head of intelligence at Le Beck consultancy.
Crucially, it reduces the area of the front line the Kremlin’s military needs to defend, he added, after a winter push that left it stretched and depleted.
“By blowing up the dam, Russia would be removing one key offensive vector from the equation,” Horowitz said.
Ukrainian officials agreed, with presidential adviser Mykhailo Podolyak accusing Russia of having blown up the dam with an “obvious” goal: “to create obstacles for the offensive actions of the armed forces.”
The U.S. government has intelligence that is leaning toward Russia’s being behind the attack, according to two U.S. officials and one Western official.
Could it have been Ukraine?
Russia said Ukraine destroyed the dam to distract attention from its “choking” counteroffensive, while Defense Minister Sergei Shoigu said it may let Kyiv move its units from the Kherson front line to where they were more needed.
Some Russian pro-war military bloggers suggested that destroying the dam would benefit Ukraine, because Russian-controlled areas would suffer the most, disrupting mine barriers and front-line positions.
Analysts did agree that the entrenched defenses Russia had built up for months would be hit, but they didn’t see a clear motive for Ukraine.
Both sides stand to lose something, Horowitz said.
“This does wash away some of the defenses the Russian army built along the coast and will certainly have an impact on many settlements in areas Russia controls,” he said, adding that for Kyiv, “this is an ecological disaster, coupled with the prospect of losing one of the major sources of energy in southern Ukraine.”
Indeed, some analysts wondered whether the act was deliberate at all or rather a result of reckless negligence by the Russian forces controlling it.
In the months before the breach, experts raised concerns about damage to the dam and warned that the reservoir behind it was too full from heavy rains and snowmelt.
“In which case, it’s a disaster for everybody,” said Frank Ledwidge, a lecturer in military strategy at the University of Portsmouth in Britain and a former military intelligence officer.
What now for the war?
It’s too early to tell how the disaster could shape Ukraine’s counteroffensive, especially because Kyiv has kept its plans secret.
But the fallout from the dam collapse could both hinder planned ground attacks and force Ukraine’s government to focus attention and resources on recovery efforts.
“One imagines they knew it was a possibility,” said Phillips O’Brien, a professor of strategic studies at the University of St. Andrews in Scotland.
Wet and muddy conditions on the ground may have already delayed Ukraine’s counteroffensive, making it difficult for heavy equipment to traverse a lot of ground.
“Now, just as it was beginning, this could leave huge areas swamped for a long time,” O’Brien said. “If that was their intention, it definitely makes it far more difficult.”
But it seems highly unlikely that the breaching of the dam will prevent the counteroffensive from taking place entirely, Tuck said.
“River assaults are problematic, so it would seem more likely that the main Ukrainian attacks will take place along land axes rather than across the Dnieper,” Tuck said. “But the flooding might disrupt prospective secondary Ukrainian attacks from that direction.”
It’s also a sudden and significant distraction for the Ukrainian government, he said.
The sheer shock of the dam collapse and the scale of the fallout could point to another potential Russian motive: an audacious warning to Ukraine that it might be willing to throw in other — previously unthinkable — twists to try to change the course of the war.
Ukrainian and global officials have been warning for months about the vulnerability of the Russian-controlled Zaporizhzhia nuclear power plant, Europe’s largest.
Russia controls southern areas of the Zaporizhzhia region, and any Ukrainian advance in the area would thrust the plant into the center of the action.
“If Russia did blow up the dam, the question is would they do the same with the nuclear plant they control that also sits in a key area of the front line?” Horowitz said.