Once an island, once much higher than it is now, Nobbys was joined to the mainland in the 1840s, when a breakwall begun in 1818 under Governor Lachlan Macquarie was finally completed.

Nobbys Beach, the curved strip of sand that runs along the ocean side of Macquarie Pier and then turns in under the lighthouse, is also a Newcastle icon, fixed in the public mind.

Except that there's nothing fixed about it.

At the northern end of the beach, a deep, fast-flowing channel almost always separates The Spit - as that corner of sand is known - from a long cluster of rocks that sit well out of the water at all but the highest of tides.

In recent weeks, The Spit has gathered so much sand that beach goers were this week able to walk all the way out to the rocks at low tide without getting their feet wet.

Although old Nobbys hands - surfers including David Kilby and John 'Reef Rat' Cullen - say The Spit filled in briefly about 15 years ago, they say it was not as wide as it is now.

And the sand is still accumulating.

It is also building up where the beach joins the breakwall at a wave called The Wedge, where the usually rocky bottom is almost entirely covered in sand.

Although it does not go into a huge amount of detail, a new report to Newcastle City Council on the erosion crisis at Stockton does confirm the accumulation of sand at Nobbys as a major factor in the Stockton "sediment budget".

In a new "quantified conceptual model of sand movement", Bluecoast Consulting Engineers list the "appearance of Nobbys Beach post-breakwaters as well as accumulation at Horseshoe Beach" as the first of five strands of evidence confirming that sand is "bypassing" the southern end of Stockton Beach.

MORE ON STOCKTON: Read The Stockton File

It is sometimes overlooked that Nobbys, because of the breakwall, is an entirely artificial beach.

The natural coast has had countless aeons to reach a general stability, but Nobbys Beach is still, in geological terms, in its formative stages.

Before Nobbys was joined to the coast, ocean swells - especially big winter "ground swells" pouring in from the south and south-east - used to wash across the reef and what was then the natural entrance to the Hunter River.

The entrance was a dangerous place, as any number of histories about the early days of sail and steam have told.

The original Macquarie Pier helped calm the harbour entrance, but it took another century and more of breakwall construction on both the Newcastle and Stockton sides - as well as harbour deepening - to bring things to the point where the big coal-carrying ships that dominate the port can slip in and out of the harbour in all but the heaviest of seas and wildest of conditions.

Fixing things for shipping has had a series of flow-on effects, however, as the residents of Stockton well know.

In nature, sand can be stripped from any beach in a big swell. But at Stockton, it's increasingly obvious that new sand - or the same sand, recirculated - is not being carried onto the southern end of Stockton Beach in the ways it once was.

Instead, experts confirm that much of it is ending up in two other places.

Some of it is deflected farther north along Stockton Beach, towards Fern Bay. But a lot of it never gets to cross the harbour mouth, and is coming to rest, instead, on the ever-increasing sand dunes of Nobbys Beach.

Old photographs show clearly what we might not notice day to day.

Back in the 1960s and early 1970s, the middle of the beach was little more than a narrow strip of sand.

Surf legend Peter McCabe said yesterday that when he and Kilby were surfing Nobbys in the 1960s, that on higher tides and decent swells it was not unusual to flick off at the end of a ride right next to the breakwall boulders themselves.

Now, anyone walking towards the headland along the breakwall has to tramp through a substantial width of sizeable sandhills to reach the tidal zone of the beach.

And it's not just the width of the beach, but the size of the dunes, which old Nobbys hands say have grown many metres higher in recent years.

While the sand around the southern end of the beach, especially, does tend to come and go, the overall trend is for it to build up, or "accrete".

Those older surfers - who generally pay very close attention to anything that impacts on the waves - are adamant that the accretion is accelerating.

They say there a few reasons for this. McCabe points to the harbour deepening and the extension of the breakwall in the 1970s.

"It all started changing pretty rapidly after that," McCabe said. "Fifteen years, that's pretty rapid."

Others reckon it was a dune stabilisation program that they remember from the 1980s, apparently at the behest of the harbour operator, which at that stage was the state-owned Newcastle Port Corporation.

Although the South African noxious weed, bitou bush, is still growing at the base of the headland, the main plants in the sand at Nobbys today are a spinifex grass and the pink-flowering succulent pigface.

The spinifex grass was apparently planted during the stabilisation program.

On a coast like ours, where sandmining destroyed kilometres of natural beachfront through to the 1980s, dune stabilisation programs have been key to environmental rehabilitation.

At Nobbys, it is said the port corporation pushed for dune stabilisation to stop sand blowing over the breakwall and into the harbour, where it apparently built up enough to require at least occasional dredging.

While the program apparently achieved that aim, the surfers say it also stops a lot of the sand that would be blown back out into the water by the westerly winds that prevail in winter.

"There's a process of erosion and accretion," David Kilby says.

"But over time, the accretion here has outstripped the erosion, and so the beach has just kept growing, and more so as you get to the northern end.

"That grass has roots that go down metres, it's like the reinforcing rods you put in concrete, that's how efficient it is."

Although the breakwalls are officially recognised as a major factor in the Stockton erosion, less attention appears to have been paid on their impact on Nobbys Beach.

The privatised Port of Newcastle said a lack of readily available files meant it was unable to confirm "the [dune stabilisation] process or even if, and when, it occurred".

Both it and the NSW Port Authority, which has closed the popular public walk along the breakwall for a major maintenance program, said the dunes in question were on land controlled by NSW Crown Lands.

The popular harbourside walk along Macquarie Pier has been closed since August, when the state authority began what it describes as a $3-million upgrading of the road and its surrounds.

The authority says the work is due to be finished before the end of the year, but the word on Nobbys Beach - perhaps from those on the job - is that it will take until early next year.

Once reopened, the authority is promising pedestrians and cyclists will be able to buy a coffee from a mobile cafe set to operate from the turning area and former car park at the foot of the road up the slope to the lighthouse.

Various sources say rescue authorities were concerned about the lack of road access to the headland when they were forced to rescue three adults and a child from a capsized boat in the ocean off Nobbys Reef on Saturday, August 29.

Newcastle council declined to let its lifeguards speak with the Newcastle Herald, but the port authority said "all emergency services" had a master key to the lock at the gate to the entrance to the works area.

Concerns had apparently been raised that the beach buggies used by the lifeguards were unsuitable for driving over the dunes - which are littered in places with rocks and other debris amongst the vegetation - if there was no room on the beach.

This happened earlier in the year when big seas pushed the waves up to the edge of the dunes, which had a "drop-off" of two metres or more in some places.

The infamous 2007 grounding of the Pasha Bulker has also been blamed for changes at Nobbys, at least in the way the waves break in the middle of the beach, where it grounded.

Some surfers are adamant that enough rocks - in particular one that John Cullen said was called "Butchers Rock" - were moved to change the right-hander off the mid-beach break, The Reef.

Others disagree and David Kilby says the biggest influence is the encroaching sand covering more and more of the various reefs that were the original sea-floor before the pier was built.

Sand that has, temporarily at least, filled in the deep channel that usually runs between The Spit and the rocks.

It's worth a walk, while it's there.

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