How was the Snowy Mountains Scheme built?

A river that flowed the wrong way

The Snowy River begins high in the mountains of south-eastern New South Wales and flows south to the sea. On the other side of the Great Dividing Range, the Murrumbidgee and Murray rivers run inland, past farms that are often short of water. People started to wonder: what if some of that mountain water could be turned around?

Australians had talked about the idea since the 1880s, and in 1944 governments set up a committee to study it. Water that falls down a mountain can also spin turbines to make electricity, so the plan became two jobs in one: water for farms and power for cities. In July 1949 Parliament passed the law, and on 17 October 1949 the first blast was fired at Adaminaby.

It was a huge task for a country of only about 8 million people, with too few engineers, tradespeople and machines. The man in charge was William Hudson, an engineer born in New Zealand who had already built dams in Australia and Scotland. He knew he would have to find workers from all over the world.

People from more than 30 countries

Hudson searched the world for skilled people, and found many in refugee camps in Europe after World War Two. Over 25 years, more than 100,000 people worked on the scheme, coming from over 30 countries, including Germany, Italy, Norway, Greece, Poland, Ireland and Britain. About two out of every three workers came from overseas. At the busiest time, in 1959, around 7,300 people were on the job.

Some of them had been on opposite sides in the war. Hudson told them that on the Snowy they were no longer Czechs or Germans: they were "men of the Snowy". Most of the newcomers stayed in Australia afterwards and became citizens.

Life was tough at first. In the early years, hundreds of men spent freezing winters in canvas tents with only basic comforts. Workers lived in more than 100 camps and in towns such as Khancoban, Cabramurra and Talbingo, while Cooma became the scheme's headquarters. Today, rows of national flags in Cooma honour the countries the workers came from.

Digging through the mountains

The heart of the scheme is hidden inside the mountains. Water cannot flow uphill over the Great Dividing Range, so the crews had to go through it. They drilled and blasted tunnels, often through solid granite, and all the tunnels together add up to about 145 kilometres. One of the longest, the Eucumbene–Snowy Tunnel, is 23.5 kilometres long and was finished in 1965.

Hard rock can crack and fall, so tunnels need support. Rather than lining every metre with concrete, Snowy engineers refined a method called rock bolting. Long steel bolts are fixed into the roof and walls, and they squeeze the broken rock together into a strong, self-supporting arch. It was cheaper and safer than lining tunnels with concrete, and it became a landmark in civil engineering and mining.

Even so, the work was dangerous. In all, 121 workers died while the scheme was being built, and Snowy Hydro still honours their memory. The authority was ahead of its time on safety in one way: in 1960 it made seatbelts compulsory in all its vehicles, about ten years before the rest of the country.

How the water works

Now picture the whole system. Sixteen big dams trap melted snow and rain in lakes, and the biggest is Lake Eucumbene. From the lakes, water is sent west through tunnels beneath the mountains. In the northern part of the scheme, the Snowy–Tumut development, it runs down to the Tumut River and on into the Murrumbidgee. In the southern part, the Snowy–Murray development, it runs down to the Swampy Plain River and into the Murray.

On the way down, the water drops through power stations, seven of them when the scheme was finished, and two built deep underground. It rushes through turbines that spin generators to make electricity, then flows on to water farms. Even today the scheme supplies more than 2,300 gigalitres of water a year for irrigation (a gigalitre is a billion litres), and its power stations make about 4,500 gigawatt-hours of renewable electricity in an average year.

What it cost

A project this big changed the land and the people who lived there. Two old towns, Adaminaby and Jindabyne, stood in valleys that were about to be flooded. Adaminaby was rebuilt on a new site, and the old town went under Lake Eucumbene in the late 1950s. In Jindabyne, new building was banned in 1959 and families moved to the new town between 1962 and 1964. In dry years, when the lakes drop, old foundations and relics of the drowned towns can appear again.

The high country was also Country for Aboriginal peoples, including the Ngarigo, Walgalu and southern Ngunnawal. People travelled up into the mountains in summer, following the migration of the bogong moth, to feast and hold ceremonies. The scheme was built on their traditional lands, at a time when governments did not recognise their connection to Country or ask for their views.

The river itself paid a price too. With so much water diverted, the Snowy River below Jindabyne Dam dwindled to about 1% of the flow it once had. In 2000 the New South Wales and Victorian governments agreed to send more water back, aiming for 22% within ten years, and extra water is still released into the river every year to help it recover.

The scheme was finished in 1974 at a cost of $820 million. In 2016 it was added to Australia's National Heritage List, which calls it a symbol of a multicultural, independent and resourceful Australia. Good history keeps both sides of the story: a great achievement, and a real cost.

📚 Words to know

Hydro-electric power

Electricity made from moving water. Falling water spins a turbine, and the turbine drives a generator.

Reservoir

A lake, natural or built, where water is stored until it is needed.

Irrigation

Bringing water to farms and paddocks so that crops and pasture can grow.

Rock bolting

Fixing long steel bolts into the roof and walls of a tunnel to hold the rock together.

Migrant

A person who moves to another country to live and work there.

🧪 Try this: build a mini water wheel

1. You will need a cork, six plastic spoons, strong tape, a pencil, two tall cups or boxes, a jug of water and a tray or sink. Tape the handles of the spoons evenly around the cork, with all the bowls facing the same way around, like the paddles of a water wheel.
2. Ask a grown-up to push the pencil through the middle of the cork. Rest the ends of the pencil on the two cups so the wheel hangs free and can spin.
3. Over the sink or a tray, pour water from the jug onto the spoons from just above the wheel. Does it turn? Count how many times one spoon reaches the top in 10 seconds.
4. Now pour from higher up, so the water has a longer way to fall. Does the wheel spin faster? Try pouring faster, and slower, and see what changes.
5. The Snowy Scheme stores water high in the mountains for the same reason: water with a long way to fall has more energy to spin a turbine. Challenge: can you make your wheel spin faster by changing the spoons or the way you pour?