KRYMSK, Russia — Forty-six new graves were cut on Tuesday in a field outside this city, where catastrophic flooding has left behind a slime of mud and anger.


Everyone here had a story of the pitch-black hours of Saturday morning, of being trapped inside homes as water rose to 6 and then to 8 and 10 feet, listening to the screams of neighbors and fear-maddened animals.


So it came as a shock, and then as the focus of anger, when officials acknowledged that they had been aware of a threat to Krymsk at 10 the previous night, but had not taken measures to rouse its sleeping residents.


The flood in this city of 57,000 in southern Russia is the first disaster to hit the country since Vladimir V. Putin returned to the presidency, amid uncertain public support for his government. Its aftermath has riveted national attention as a measure of the state’s effectiveness, including visits from celebrities and volunteer efforts backed by pro-government and opposition political parties.


Mr. Putin has been damaged in the past by appearing indifferent to disasters — most acutely in 2000, when he failed to immediately return from a vacation to handle the sinking of a nuclear-powered submarine, the Kursk. Russia declined initial rescue offers from other countries, and all 118 sailors trapped onboard died.


The official death count in the floods had risen to 172 by Tuesday. Inside a ruined pastry shop, which had the sickly smell of something rotting, Sergei Viktorovich, 45, described waking in the darkness to the sensation of moisture in his bed, then reaching for his phone on a bedside table to find that it was already lost in the water.


“If they knew at 11, why didn’t they warn us? What are we, hunks of meat? Are we not people?” he said, offering his patronymic, not his surname, because he said he feared retribution from the police. “We are the young people, so we swam, but what about our grandmothers? How many grandmothers drowned?”


He said those emotions were barely restrained when the region’s governor, Aleksandr Tkachev, met with residents on Sunday. “If there weren’t so many police around,” he said, “they would have thrown rocks at him.”


Whatever the ultimate repercussions — firings, compensation, criminal charges — a visit to Krymsk offers a view of the gap that has opened between Russians and their government. Rumors have taken on such force that, on Monday, word of a second wave of water sent many people running.


“Even if Tkachev was saying the same things as the people standing in line for humanitarian aid, they still wouldn’t believe him,” said the journalist Oleg Kashin in a commentary on Kommersant FM radio. “Because this is not about the fact that the official story is different from the victims’ story, but that people don’t trust the authorities, on any subject — on natural disasters, or elections, or soccer.”


Mr. Putin has made clear efforts to avoid repeating earlier mistakes — as well as unscripted scenes like one during the 2010 forest fires, when he visited a burned village to offer monetary compensation and a woman began yelling angrily: “We asked for help! We trusted you!”


He reviewed damage from the air on Saturday, and has demanded a full investigation by the end of this week.


The federal authorities have since acknowledged that failing to warn residents was a major mistake, and the head of the region, Vasily Krutko, was dismissed on Monday. They have sent teams of psychologists, and donations of food and clothing have poured in.


That has not appeased many people in Krymsk, who spent Tuesday scraping mud from their floors and walls, and lining the roads with fetid piles of ruined belongings. Lyudmila Dmitriyevna, 64, said she awoke early Saturday to the sound of voices, stepping onto her third-floor balcony and peering into the gloom.