Minmi's hidden lifeline

That was a popular cry among surfers in the 1970s when Newcastle locals wanted a leg pull of gullible outsiders asking where the best surf breaks might be.

The outer residential suburb of Minmi, of course, is nowhere near the sea, although the tiny hamlet of Hexham close by is beside the Hunter River.

As the crow flies, Minmi is diagonally across the giant Hexham wetlands (or swamp as it was once called).

And that's where the mysterious joke about the great surf at Minmi Breakwater originated. For almost 160 years there's been a solid earth embankment cutting across the wetlands from the old coal mining township of Minmi towards the main Maitland-Newcastle railway at distant Hexham.

On top of this impressive man-made earthwork once ran a railway over the low, boggy ground and sea of rustling reeds.

An extra bonus of this five-kilometre swamp railway was that it was flood-free, although in times of heavy rain water did rise on either side of the causeway. That's when, especially during winter fogs, it resembled Stockton breakwater, isolated and spearing into the sea.

But the former swamp railway section is only a teaser. This now defunct steam-era railway line is part of an abandoned, once great rail line pushing 26.5 kilometres into the hills through three heritage tunnels towards the former Hunter showpiece colliery of Richmond Main, outside Kurri, and Pelaw Main.

This long hidden historic rail route snaking into the Mount Sugarloaf range was the brainchild of the autocratic coal baron John Brown. He died in 1930, but not before setting Newcastle up to later become the world's biggest coal export port.

The whole extended railway from Hexham to the Coalfields became known as the Richmond Vale Railway (or RVR). And in 1987, when the last section of line was closed, the RVR was regarded as the last commercial steam train operation in Australia.

Now fresh eyes are looking at recycling the deserted RVR line, but this time as a new regional cycleway (once linked with Shortland to make it 32 kilometres). This then might inject more than $5 million into the Lower Hunter economy each year.

Newcastle City Council has already compiled a draft feasibility plan into the idea but is seeking more information about potential costs, according to a recent news report by Herald colleague Matt Kelly.

At this point, a fully sealed trail would cost more than $13 million without, presumably, the cost of rebuilding two large decaying timber bridges and restoring two ageing, brick-lined rail tunnels.

Members of the Newcastle cycleway fraternity have applauded the idea as a tourism venture, comparing it to the highly successful Adamstown-to-Belmont Fernleigh Track.

With money from grants, anything is possible. One major hurdle, however, to any shared pedestrian/cyclist trail into the hills, might be a large modern, concrete rail tunnel (pictured) near Stockrington, near Minmi.

Never used, it was constructed 11 years after the last coal train ran on the RVR steam railway.

It was built as part of a $59 million, four-lane extension of the then F3 Freeway (now M1) between Minmi and Beresfield and parallel to Lenaghans Drive opened in late 1998.

Back in 1995, the Roads and Traffic Authority (RTA) designed the spacious new rail tunnel to allow State Rail's largest train to pass through beneath the freeway. Provision of the tunnel, measuring 83.5 metres long, 6.5 metres high and 8.4 metres wide, was one of the approved conditions attached to the environmental impact study for the whole road project there.

Someone was safeguarding a future transport corridor for coal freight trains should the idea ever be needed.

And back in 1999 there was indeed a major proposal for a special freight line to exploit a North Wyong coalfield. A new dedicated line would have linked Fassifern with Hexham, but it never happened.

Meanwhile, that particular 5.5-kilometre section of F3/M1 highway between Minmi and Beresfield became an engineering marvel as the swamp posed a real challenge requiring an ingenious, high-tech solution.

An innovative method, consisting of high-strength polyester geosynthetic reinforcement, was used to make sure the national highway (or anything else, like a tunnel) did not sink into Leneghans Swamp.

Combined with recycled power station ash, BHP blast slag and deep vertical wick drains to allow water to escape, it was estimated the scheme would reduce the road/earth settlement period from 300 years to three.

And long before European settlement occurred, the Pambalong tribe had occupied the region around Minmi. It was around here that scraping and grinding tools and 37,000 spearhead barbs and other artefacts were uncovered by freeway builders.

The extended, steam-era RVR from Hexham to Pelaw Main opened for coal traffic in 1906 and walking along its route today shows what a grand vision "Baron" Brown once had.

The original, short line from Hexham to Minmi across the swamp probably opened in early 1857 and was conceived by famous Hunter pioneer John Eales and his partner John Christian who had opened coalmines at Minmi.

John Brown later took over, ambitiously pushing his private line westwards, towards Kurri, around 1900. Then about 1909, taking advantage of a coal strike, he had workers double the width of the Hexham-Minmi swamp railway.

Pelaw Main Colliery closed in 1962 and Richmond Main in 1967. The rail lines west of mines at Stockrington were lifted soon after.

So, what might future cyclists and bush walkers expect meandering through bush on the old Richmond Vale line, Australia's last commercial steam railway?

Today the abandoned line west of Minmi includes the neglected and dangerous timber bridges at Surveyor's Creek and Wallis Creek and the three still impressive, now disused brick tunnels.

Two of them are often flooded, but considering there's been no maintenance, all tunnels appear to be in good condition. In style, all resemble the once unwanted brick rail tunnel at what is now the popular Fernleigh Track at Adamstown Heights.

Oddly enough, much of the original, colourful history of the RVR line, especially around Hexham, may never be known because it was never written down.

There's only intriguing hints about Chinese labourers helping build the line in 1854, but having to sleep on the unfinished track as they weren't allowed into Minmi itself.

The same tale is told about Russian navvies and up in the hills a Welsh Town, or Welsh Valley, is said to have sprung up. It's also claimed that in World War II, an Italian POW camp was located nearby.

All in all, any future walk or cycle through bushland here would be full of interest.