Odessa was ready to reclaim its beaches. Then a dam broke.

Last summer, the beaches around the port city of Odessa in southern Ukraine were littered with volunteers packing sandbags under cliffs where troops were positioned in machine gun nests as the threat of a Russian amphibious assault still loomed.

This summer should have been different. In the first days of June, the sun was warm, the Black Sea shimmering blue, and despite an official swimming ban, many Ukrainians were already packing the beaches.

Then the Kakhovka dam was destroyed.

It unleashed a deluge of water that poured down the Dnipro River, engulfing towns and villages in southern Ukraine. Thousands of homes and businesses were inundated, vast fertile farmlands were ravaged, and the full environmental and economic costs are likely to be measured for years to come.

The floods also brought mounds of debris to the Black Sea – bits of buildings, trees, appliances, boats, cattle carcasses and even instruments of war, such as the land mines that both Russian and Ukrainian troops had planted near the river. Now the tides carry much of it to the coast, along with a stew of toxic chemicals polluting the famed beaches of Odessa and other coastal communities.

“The sea is turning into a rubbish dump and animal cemetery,” the Ukrainian border guard warned last week. “The consequences of ecocide are terrible.”

It said there was a “plague of dead fish” among the houses and furniture, mines and ammunition that washed ashore. On Saturday stated the Odessa City Council that swimming was banned on all beaches in the city, calling it “dangerous to the health of citizens”.

Before the dam broke on June 6, city officials were busy installing protective nets in the water to catch floating sea mines, such as the nets that protect swimmers in other parts of the world from sharks. But there is no system in place that can stem the deluge of debris now hitting shorelines, emergency and military officials said.

In recent days, mines from the Dnipro have washed up in Odessa, more than 100 miles away, the local branch of the State Emergency Service said. One was found by a resident who thought it was a bottle of cooking gas and picked it up. Somehow it didn’t explode.

“He brought it home, but luckily common sense won out and he called the mine clearers,” the agency said.

The destruction of the dam could mean another summer cut off from the sea, a bitter blow to a city already suffering from intermittent Russian missile strikes and the loss of its port, with all but a few grain ships destroyed by a Russian blockade prevented from sailing.

Igor Oks, creative director of a new international cultural center in Odessa, said that the city without a port is like a body without limbs. Not being able to enjoy the sea, he said, is like cutting out one’s heart.

He remembered the scene a year ago, amid fears of a Russian landing, when the beaches were prepared for battle, marked by trenches and steel girders welded into tank traps.

“There were bags of sand everywhere and volunteers came to the beach every day to fill these bags,” he said. “I remember going to the beach and watching the level of the sand drop like a foot or five feet.”

City officials estimate that 700 tons of sand had been excavated from beaches during the early months of the war when the alarm was at its peak.

At that time, Odessa was still facing a Russian threat from land, air and sea. Now the Kremlin’s land forces have been pushed back and the warships are keeping a wary distance as improved Ukrainian coastal defenses have put them in danger.

But the dam’s destruction has brought new dangers, threatening to dampen a resurgence of life and commerce in a city that has long been a favored escape route for people across Ukraine.

With President Vladimir V. Putin’s hopes of taking the city seemingly far out of reach, the citizens of Odes sought to recover some of the summer excitement that helped the city earn its reputation as ‘the pearl of the Black Sea’ .

Once a small outpost of the Ottoman Empire, it was conquered by Russia in the 1790s, refounded and renamed by Empress Catherine the Great, and grew into a prosperous port and seaside resort, known for its beaches and elegant architecture.

In early June, ballerinas from a dance school held a class on a boardwalk in the morning, an open-air cinema was set up for a summer film festival in the evening, and music poured from the cafes all day long.

The famous Potemkin Stairs – 192 steps leading from the city to the harbor – have been closed off, as the harbor remains a target of Russian attacks, but most of the checkpoints around the city have disappeared. The restaurants and bars are busy, and before the dam broke, workers were cleaning the sand on the beaches, not digging it up.

Now they must keep pace with a deluge of often dangerous debris.

Mykola Kaskov, 47, head of the rescue-diving unit of the state emergency service in the Odessa region, said that even before the dam broke, naval mines detaching from their moorings posed a continuing risk. But his mission remains the same.

“The most important thing is to keep people alive,” he said.

Last summer there was a swimming ban, but several people died on the beaches due to mines. A 50-year-old man who took to the water in search of sea snails, an Odesan delicacy, was blown up last June when his family watched from shore.

A month later, a young man went swimming and “was blown up by a mine on his birthday,” said Serhii Bratchuk, spokesman for the Odessa military administration. said at the time.

That danger is now much greater, warned the Ukrainian military southern command.

Yevhen Koretskyi, 24, a demining specialist for the state emergency service in the Odessa region, has been training on a new underwater drone designed to search for explosives. They received the new equipment just days before the dam burst, but are already commissioning it.

He demonstrated the equipment in an empty marina on the outskirts of the city and said he and his colleagues would soon be using such devices to help protect swimmers in the sea, as well as in recently flooded rivers and lakes.

Viktor Butenko, 41, a rescue diver, was testing another nearby device that should be used if they were running late.

“This catamaran drone is for searching for bodies,” he said.

Before the dam’s destruction, many residents of Odes said they were ready to dip their toes back in the water despite the dangers, though some more cautiously than others.

Olena, 40, who was on the beach with her 7-year-old son in early June, said she was “gradually” approaching the sea.

“I first came to the sea walk,” she said, referring to the cobbled path behind the sand. “Then to the beach, and finally tried the sea.”

“I haven’t had a bath yet, too cold for me, but my son goes in the water,” she added. “Of course we are afraid of the mines, but it is time for summer holidays and it would be too sad without the sea.”

Now there are more mines and also other threats. The sea, officials said, is once again too dangerous to enter and it looks like another beach summer could be lost in the war.

Anna Lukanova And Evelina Riabenko reporting contributed.