A man from the NSW south coast has been confirmed as the first Australian killed in Nepal’s devastating flash flood disaster, as rescue teams continue their desperate search for survivors.

Michael Keats was travelling to India for a spiritual retreat when the catastrophic floods struck. His heartbroken family is now asking for support.

WATCH THE VIDEO ABOVE: Australian man Michael Keats confirmed dead in Nepal

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Deep in the disaster zone is the town of Betrawati, where so many remain missing.

In one of the world’s poorest countries, the further north you go, the tougher it gets. Few people have been here since the flood hit.

Betrawati, home to 2000 people until last week, has been decimated. There’s not much left.

One local man lost his sister-in-law when the nightmare wall of water came crashing through. Her body is still trapped inside the house.

Military personnel have landed by helicopter, bringing medical supplies and food as crucial international aid follows.

But with each hour, more bodies are being found. The death toll has now climbed above 900.

The only way to reach the homes is to crawl across the sludge. It is slow, dirty, heartbreaking work.

Nepal’s long, dark hydropower tunnels have become ground zero in the search for survivors. Crews are carrying in oxygen supplies with only iPhone lights to see, hunting for signs of life.

The death toll from the disaster has grown to more than 900, including Australian man Michael Keats. Credit: 7NEWS

Some men barely made it out alive. There’s hope their workmates still could too.

Australian tunnelling expert Professor Arnold Dix said the situation is extraordinary.

“My power station, I think we could have potentially in the order of 40-something people trapped and alive inside it,” he said.

Crews from all over the world are helping with the complex rescue, including Australia.

Further south, conditions are pushing everyone to the limit. Locals are being looked after in shelters set up inside schools.

Aid worker Jyoti Gaihre said there is also concern for the survivors.

“Really worried about food and sanitation for the people, those who have already lost the houses, and we don’t want them to suffer more,” she said.

Getting anywhere is near impossible. One distraught mother has been separated from her three-year-old son and nine-year-old daughter. They’re stuck at school on the wrong side of the river.

“I have been crying,” she said. “Asking for help, but nobody is helping.”

It’s the hellish reality many are facing in Nepal.

Rescue teams are hopeful but aware that no survivors have been found anywhere in Nepal in the past 24 hours.

Just across the river from Betrawati is the district of Rasuwa, where the majority of the 43 missing Australians are believed to have been during the flash floods.

Families of those missing have made the journey to Nepal and are making their way deeper into the disaster zone in search of answers.

Prime Minister Anthony Albanese says the Australian Air Force will depart with desperately needed aid for locals in the area in the coming days.

How you can help

The Emergency Action Alliance — involving 15 leading charities — is uniting to manage donations to help the people of Nepal.

Donations can be made online or by calling 1300 939 000.