Australians have a deep affection for the project. It is ingenious. It is renewable energy without too much ideological baggage. Unlike onshore gas extraction, it may not irk too many farmers. It might even turn out to be tolerable for environmentalists

The project took a quarter of a century to build, largely on the back of migrant labour, and remains one of the greatest engineering marvels in this nation’s history.

The construction of it was a defining point in Australia’s history; a potent symbol of our identity as an independent, multicultural and resourceful nation.

It’s also one of the most complex water and electricity projects on the planet. 

Including 16 major dams, seven power stations, a pumping station and 225 kilometres of tunnels and pipes, the scheme, among other things, collects water from melting snow and rain and diverts it into dams. 

The water is then used to create electricity before flowing into the Murray and Murrumbidgee and, in part, to irrigators.

The scheme was originally built both for irrigation purposes and to generate base-load power.

But as the nation’s energy needs have evolved, so too has the scheme.

In recent years, it has been used to top up electricity supply at peak times.

On Thursday, the next incarnation of the awe-inspiring scheme was announced.

Flanked by media at the Tumut 3 Power Station, Mr Turnbull announced a game-changing, $2 billion expansion.

It will increase the amount of electricity the scheme uses by a staggering 50 per cent, enough to power 500,000 homes.

It will create thousands of new jobs for the region and help breathe fresh life into surrounding towns and villages.

This is not just a ten-figure investment in power security, it’s an investment in regional NSW. And at a time when the rising cost of energy has become a searing household issue, it’s an investment in Mr Turnbull’s political future.

It will also help muffle the cries of environmentalists desperate to end coal-fired power.

Mr Turnbull has struggled to strike upon a “big idea” as PM, instead looking reactive and indecisive. He can only hope this announcement creates energy for the nation – and for his flagging popularity.