As Fighting Rages, Ukraine Claims a Gain in Southeast

Although the waters have receded, Ukraine’s State Emergency Service, local volunteer groups and aid agencies were struggling to respond. At least 14 people were killed in the flooding and at least 35 others were missing, while dozens of communities have been cut off from clean water.

The river’s frontline location has further complicated rescue efforts. Russian forces that retreated from the city of Kherson in November to the eastern bank of the Dnipro have launched thousands of rocket and missile attacks back across the river. A total of 41 shells had exploded over the previous 24 hours, Ukrainian authorities said on Saturday.

Officials were also grappling with the environmental toll, which has horrified Ukrainians already battered by 15 months of Russian aerial attacks, the torture and deportation of civilians and the occupation of parts of their country.

Russian troops controlled the dam, and engineering and munitions experts have said that a deliberate explosion inside it probably caused the dam’s collapse. American intelligence analysts suspect that Russia was behind the dam’s destruction, but do not have conclusive evidence yet about who was responsible. Moscow’s accusations that the government in Kyiv was responsible for the disaster have been met with scorn in Ukraine.

In its latest update on the toll of the disaster, Ukraine’s internal affairs ministry said that 77 urban settlements in the Kherson and Mykolaiv regions had been flooded. It added that rescue workers had evacuated more than 3,600 people, many of whom are elderly. Many more residents have fled the area in cars and by rail on their own.

Ukrainian authorities said that six people had died, while pro-Russian officials earlier put the death toll in the area of Kherson region that they control at eight.

The surge of water through the dam peaked a few days after the explosion and has since started to diminish as water rushes into the Black Sea. On Sunday, Ukraine’s state hydropower company, Ukrhydroenergo, said the water level in the reservoir had dropped by around three feet in the previous 24 hours, and by more than 21 feet in total since the dam collapsed.

The reduction in the water level poses a new risk to the Zaporizhzhia Nuclear Power Plant, which is situated on the reservoir’s eastern bank and is controlled by Russian forces. The plant, which this week put the last of its six reactors into a cold shutdown, uses reservoir water to cool its reactors and spent fuel.

It also complicates the military calculations for both sides as a Ukrainian counteroffensive gets underway to retake land in the south and east of the country.

The dam disaster has polluted water supplies and, over time, it will deplete groundwater levels upstream — creating a long-term problem for a population well beyond those living in the immediate flood zone. In one initial indication of the impact, the internal affairs ministry said that 162,000 customers in Dnipropetrovsk region, which is upstream of the dam, were without a supply of clean water.

It will also affect irrigation that feeds the fertile land in the river’s basin, a rich source of the country’s agricultural exports, and threaten wildlife in a region with several national parks.

“The situation in national parks is critical,” said Ukraine’s environment minister, Ruslan Strilets, in a post on Facebook.

On the Russian-held east bank, Vladimir Saldo, the Kremlin-installed governor, said on Saturday morning that more than 6,000 people had been evacuated from the Russian-held flooded territories, including 235 children. More than 60 people had been hospitalized, he said on Telegram.

The dam disaster also poses potential problems for Crimea, a dry region illegally annexed by Russia in 2014 that relies on a canal fed by the Dnipro River for some of its water supply.

The flooding has “severely disrupted this primary water source,” according to a report issued on Sunday by Britain’s defense intelligence agency.