It had begun as just another day at work for Rajan Shrestha.

The mayor of Bidur Municipality was taking the usual stream of calls that came from residents and elected representatives from early morning. Some required his attention immediately; others could wait.

Then, at about 9am on Wednesday, came a call that could not be ignored.

The district National Disaster Risk Reduction and Management Authority was warning of a flood.

Shrestha immediately alerted elected representatives in every ward. Schools and local communities were informed, while vehicles carrying loudspeakers drove through the town, broadcasting warnings for people to evacuate to safer ground.

There was just enough time to send out the message before the disaster arrived.

Half an hour later, Bidur had been transformed.

“I had never seen such a massive flood in my life,” Shrestha said. “And it came so fast. We could not evacuate all the people from the main town.”

Bidur, a fertile river basin valley spread along the banks of the Trishuli and Tadi rivers, had long been one of the more prosperous municipalities in the region. Its low-lying land and warm subtropical climate had helped sustain settlements, farms and businesses.

On Wednesday, however, the rivers turned against the town.

By 9.30am, floodwaters and mud had swept across the municipality, tearing away bridges, flattening buildings and leaving familiar neighbourhoods almost unrecognisable.

“We are familiar with floods,” Shrestha said. “We had seen a surge in water and mud in the Trishuli only last month, so we were not so worried.

“But this was a catastrophic calamity, causing unimaginable loss of life and property.”

The scale of the disaster became clear only as the waters receded.

Shrestha fears that about 400 people may have been swept away, despite the emergency warnings issued before the flood struck. The official toll was still being compiled as search and rescue teams struggled to reach devastated settlements.

“No one had thought it would be so massive,” he said.

Only weeks earlier, on August 9, residents had seen muddy floodwater surge down the river. Such episodes were not unusual and few imagined what was to come.

In Tupche village, Nawaraj Nepal, 56, received warnings to move to safety. Instead, he went to his cattle shed to untie his buffalo.

He never returned.

For Yasoda Nepal, 42, a teacher at Chandewhwari Secondary School, the warning left barely enough time to make an impossible choice.

She had reached the school to collect children and evacuate them to higher ground when she realised that her own 93-year-old grandmother was at home.

Tupche sits on a hillside more than 200 metres above the river. Nepal rushed from the school to rescue her grandmother and somehow managed to get both the children and the elderly woman to safety.

Her own house was inundated up to the second floor.

It survived only because a larger building in the path of the torrent absorbed much of the force of the current.

“The flood came like a slap in the face,” she said. “It came at lightning speed and took everything with it.”

Among those she lost was Nawaraj Nepal, the man who had gone to untie his buffalo. Govinda Bhattarai, 55, from the same neighbourhood, was also missing.

Bidur was among the worst-hit areas as the flash flood tore through communities along the river system, affecting six districts — Rasuwa, Nuwakot, Dhading, Gorkha, Chitwan and Nawalparasi.

According to Nepal Police, at least 157 bodies had been recovered, while hundreds of people, including tourists and government personnel, remained unaccounted for. The figures were expected to change as search teams reached areas cut off by destroyed roads and bridges.

Shrestha's own side of the slope escaped the worst of the flooding. But the disaster swept away every bridge connecting him to parts of his municipality.

To reach his office, he said, he would now have to travel by boat.

The town centre had been devastated.

The Trishuli Power House, one of Nepal's oldest hydropower plants, with a history stretching back about 60 years, was destroyed. Old prison buildings were also damaged, although the inmates had been released before the flood struck.

For Shrestha, the destruction has left him wondering whether even a little more time could have changed the outcome.

The warning reached him only about half an hour before the flood came.

“I wish they had alerted us an hour earlier,” he said. “It would have been much better.”

The disaster comes little more than a year after another catastrophic flood in the region. In 2025, a flash flood in the Lende River, a tributary of the Bhotekoshi, destroyed the Nepal-China Friendship Bridge at Rasuwagadhi and severed the vital trade route to Kerung. Authorities suspected that disaster may have been caused by a glacial lake outburst upstream in Tibet.

But for the people of Bidur, comparisons offered little comfort.

The warnings had come. Loudspeakers had carried them through the streets. Teachers had raced to save their pupils and families had fled for higher ground.

Still, for hundreds, the river had arrived too quickly.