All that will change in a fortnight when the mighty Snowy Mountains Scheme officially celebrates its 70th anniversary and commemorates the hardy men from Snowy River who made it happen.

But if some young Novocastrians now don't know about the BHP Steelworks and being called Steel City until 20 years ago, what hope have they got to know about the, now renamed, Snowy Hydro, project?

The extraordinary Snowy Mountains Scheme (SMS) was an engineering marvel carried out more than 25 years from 1949 to 1974.

The nation had only a population of eight million when this giant network of dams, tunnels and aqueducts began with the first explosive blast at Adaminaby (population 200), near Cooma, in southern NSW, on October 17, 1949.

Built to provide plentiful and reliable power and for irrigation, the imaginative scheme emerged in "an era when Australia dared to have a vision" as writer Thomas Keneally once wrote.

It was also about the making of modern Australia, with an army of workers digging tunnels through the Southern Alps to drive river flow through turbines to generate electricity.

Consider the mind-boggling statistics: on completion, the SMS had built 16 major dams (up to 76 metres high), seven power stations, 80 kilometres of aqueducts and 145 kilometres of interconnected tunnels.

The Snowy Scheme also involved a total of 100,000 workers being employed from 32 countries.

The brutal, dangerous work was often carried out in freezing conditions with 121 people losing their lives to make the engineering dream a reality.

Like building the Panama Canal, the Snowy Scheme was one of the engineering wonders of the world.

The historical cost of transforming an area the size of Switzerland was $820 million in 1974, but later updated (in 2004) to at least $6 billion.

The monumental task of tackling the wild mountain country where skiers now roam, began with adventurous geologists and surveyors camping rough in snow as the area, until then, had never been surveyed in detail.

Such has been the success of the scheme that former prime minister Malcolm Turnbull proposed in 2017 a multibillion-dollar expansion, dubbed Snowy 2.0, to increase the electricity generated by 50 per cent, or enough to power 500,000 more houses. It's a far cry from an idea many years ago, but never taken up, to generate hydro-electricity from a power station in Barrington Tops.

But, back to the Snowy Scheme. The concept of diverting water from the Murray, Murrumbidgee, Snowy and Tumut rivers dates back to the 1880s. It wasn't until 1944, however, that a committee was formed to investigate the scheme's feasibility. Then, 70 years ago this month, the Snowy Mountains hydro-electricity authority commissioner (later Sir) Bill Hudson fired the first blast. He presided over the project for 18 years.

The man who greatly helped make the Snowy Scheme happen though was Hudson's offsider, Nelson Lemmon, who said later with characteristic bluntness: "After the Snowy, Australia was a nation".

Lemmon was among 400 people once interviewed by Irish writer Siobhan McHugh for her landmark book The Snowy - a history, first published in 1989 and reprinted again this year in an updated 70th anniversary edition. The remarkable book offers a unique insight into the project.

McHugh's book started life as an unusual ABC radio project. It developed into a comprehensive history of the scheme's trials and tribulations, the human stories of the migrant workers, plus politicians and engineers.

The six half-hour radio documentaries aired in November 1987. A rich audio tapestry of accents and life stories was revealed. McHugh said it was the first time that 'ethnic' voices outnumbered Australians on the ABC. But, it was the tip of the iceberg. It needed a book.

She had opened a door into a post-war social engineering feat that helped create today's diverse multicultural nation. The European arrivals included not only Irish, English and Germans, but Italians, Poles, Latvians, Serbs and Croats, Lithuanians, Latvians, Estonians, Czechoslovakians, Russians and Norwegians. Adding to the volatile mix was the knowledge many new arrivals had been dire enemies in the recently ended Second World War, but had to put this aside to work together.

The more McHugh delved, the more fascinating it became. She heard harrowing stories of survival, like from a Serbian who had earlier been in a forced labour camp in Germany and also tales of derring-do and danger: like the truck driver who, when his brakes failed, kept his vehicle on the road for half a kilometre until plummeting to certain death on a mountain bend.

Or the terrible tale of workers trapped down a shaft by an avalanche of liquid concrete and debris.

McHugh got one of her big breaks with an interview with a retired Nelson Lemmon at Port Macquarie. She only got that break because his mother-in-law had once come from a small Irish community. McHugh was extremely lucky. Six months later, Lemmon was dead.

One of the beauties of this book, describing events of 70 years ago, is that the author spoke to her subjects more than 30 years ago when their memories were sharper.

One of the more startling episodes in the book (to me anyway) was the revelation that political screening of migrants back then was "aimed more at detecting communists than at detaining fascists". Special clearances, for example, were issued in 1950 to recruit 127 skilled Germans, including top scientists. More than 40 of those brought in between 1946 and 1951 were later revealed to have Nazi party links. Two were later deported. One respected German technician, when drunk, would start boasting and show photos of Russian soldiers and others he had executed.

Another forgotten episode in the life of the Snowy Scheme was the push in 2005-06 to privatise it. After the move was roundly condemned, a co-owner, the federal government, said it would not sell its 13 per cent stake in the project. The NSW and Victorian governments followed suit. An embattled federal politician had also asked that, if the national government only owned 13 per cent of the project, why was it "copping 100 per cent of the sh*t" on the issue.

The final word on the Snowy Scheme should go to McHugh. As she writes: "Today, Australia is regarded as one of the most successful multicultural societies in the world - and the Snowy was where it all started. Hats off, then, to the Balts and Dagoes, the ten-pound Poms and Irish navvies, the garlic-munchers, reffos and squareheads - indeed all the Bloody Wogs! You reclaimed those put-downs and turned them into monikers of affection. You came here seeking A Better Life - and in the process, you created a better Australia."