Lead designer Sean Burke gives a guided tour of Onehunga's new $28m reclaimed foreshore, which was built to restore the shoreline destroyed almost 40 years ago.

Earlier this month I inched through clogged midday traffic to Auckland's newest beach, with a plan to wriggle my toes in the shelly, metre-deep white sand had been barged there all the way from Pakiri, perhaps even to roll up my trousers and paddle in the painstakingly re-created shallows, or lie back and soak up some late spring sunshine on the artificial hills built with stuff left over from digging the Waterview tunnel.

Some hope. Spring felt like winter. By the time I'd parked on the carpark's clean black asphalt and tapped on the door of the Fulton Hogan portacabin, something near a gale was roaring off the white-capped brown waters of the Manukau Harbour, whipping up handfuls of imported sand and tossing it up the beach and over the sculpted hillocks that block off sight and sound of the eight-lane motorway behind them. I kept my shoes and shirt on.

It would be justice if some of that sand ended up choking the wheel-bearings and engine valves of the trucks and cars roaring past on State Highway 20: the foreshore strikes back, or something. Because this stretch of road (which many Aucklanders know only as that straight stretch not long after you've seen the giant Holcim cement silos when driving home from the airport) is what destroyed Onehunga Bay. In 1977 the motorway sliced across the south-facing bay, totally cutting off an entire suburb's harbour access.

Jason Dorday Cyril Skilton, 87, on one of Onehunga's nine new beaches. Cyril used to swim at Onehunga Bay in 1930s and saw it destroyed by the SH20 motorway in 1977.

Now, though, Onehunga has nine new beaches, three of them sandy. It has 10 new rocky headlands that lead up to gentle hills decorated with 40,000-odd native plants and some lovely park benches. There's a carpark, winding walking tracks and a boat ramp with a freshly-dredged channel into the muddy Manukau.

All this is built on a 6.8-hectare strip of freshly reclaimed land that runs along the motorway's southern flank. It's as if someone sliced the old foreshore off with a Stanley knife and hid it in a bottom drawer for 40 years, before taking it out and gluing it back on to the edge of the motorway, where it can once more feel the tides come and go.

Sure, there's still that honking great motorway between Onehunga and the new water's-edge, but there's also a wide, beautifully wood-lined footbridge across it, which lets you stroll from 'burb to beach while almost forgetting the stream of vehicles beneath your feet.

Jason Dorday Landscape architect Sean Burke, lead designer of the new Onehunga foreshore that was built to replace the beaches obliterated by a motorway in the 1970s.

New beaches much like these were promised to the people of Onehunga in the 1970s before the motorway was built, but the promise was broken. It was only after a dogged campaign by locals that it was finally honoured. On Saturday the new foreshore will open to the public. This is the $28 million foreshore that was nagged into existence.

Cyril Skilton has lived in Onehunga for 87 years. As a boy he'd walk down to the flat, firm-sanded beach. There was a changing shed. Dozens of families in the mainly working-class suburb had a boat. He and the other kids would dive from the sand-barges that sometimes moored offshore.

"It was always nice to sit on the edge of the beach and watch everyone enjoying themselves."

Supplied: Onehunga Enhancement Society The Onehunga foreshore, photographed around 1950 by a member of a local family before State Highway 20 separated the Manukau Harbour from the town centre.

When the motorway came Skilton doesn't recall much local protest. Most people thought the Ministry of Works would put the beaches back as promised, "but all we got was a lagoon that got filled with seagrass". If locals did think to take action it was more often because "Auckland city decided to use the Manukau as their sewer. We kept complaining about people dumping things into our harbour."

Nothing much happened until 2006, when plans to widen the existing motorway to eight lanes were announced. Rumbling dissatisfaction turned into action – the formation of The Onehunga Enhancement Society, led by local businessmen Jim Jackson and Peter Gibson.

Jackson didn't muck around. He hired a top lawyer who determined that the road-builders had a clear legal obligation to fix things. Auckland Council said the work would cost $65 million but Jackson produced a rival report showing $30 million would do (one saving was the use of 55,000 cubic metres of fill dug for the Waterview project). Eventually NZTA found $18m and the council found $10m, and that proved enough.

Jason Dorday Landscape architect Sean Burke trials one of the new low hills he designed to shield Onehunga's restored foreshore from the nearby motorway.

Early on local iwi argued that fixing a bad land reclamation with more land reclamation didn't make sense, but they later joined a mana whenua consultation exercise and came on board. There was also a tussle with Trustpower, whose gargantuan transmission pylons march through the land and sea nearby.

"For nine years," says Jackson, "I put a lot of time and money into it. The end result is that the people who were totally opposed to me, the politicians and so on, today are saying how fantastic it is. Sometimes you have to stand up and be counted, and I've done that."

When I took a stroll along Onehunga's fake foreshore, the official opening was still 11 days away. There was bubble-wrap hiding the large hilltop sculpture, and orange-mesh fencing around expanses of threadbare lawn. There were gaps in the bridge's carved wooden cladding, and hi-vissed gardeners was weeding tidy rows of rushes. Transplanted pohutakawa were flopping about in the wind, looking thankful for the stakes and straps keeping them upright.

Supplied Aerial view of Onehunga, 1940s, before the SH20 motorway cut the town centre off from the foreshore.

Fake beaches. Fake headlands. Fake hills. They're all impressively naturalistic in their shape, but you can't help thinking they'll look better once the plants are a shaggier and there's a bit more barnacle and birdshit on the clean rocks.

The lead designer is landscape architect Sean Burke from Isthmus Group. For five years he's nursed the project through tender, through concept designs, through RMA hearings and mana whenua consultation, then actual construction by contractors Fulton Hogan and engineers Tonkin & Taylor (plus structural engineers URS for the bridge).

Burke's foreshore gets a chapter to itself in a book Isthmus has just published skiting about its favourite projects, including New Plymouth's coastal walkway, Ponsonby's Vinegar Lane redevelopment and the 2004 reconfiguration of Wellington's Oriental Bay so its sand didn't keep getting washed out to sea.

Supplied Recent aerial view of Onehunga showing how the SH20 destroyed the Onehunga Bay foreshore, replacing it with a lagoon. The photo predates construction of a new foreshore to the south of the motorway.

Burke, and Isthmus's CEO Ralph Johns, are chuffed with the Onehunga project, though Johns is keen to clarify the $28m budget. He says about $5m went on "contingency" and council costs, leaving Isthmus a working budget of $23m – of which $3m went on the bridge.

"Normally," says Johns, "we're working on top of land. This project is unusual in that we're actually creating the land."

Up top it might look like some bark and nice plants and a few benches, says Johns, but most of the $20m "is under your feet".

As far as they know it's the biggest land reclamation for purely recreational purposes in the Southern Hemisphere. Burke is especially proud of the headlands – rocky outcrops jutting out between each of the curving beaches.

"We looked around the Manukau and existing headlands and created a suite of naturalistic forms, " says Burke.

Brand new landforms are something usually left to God, or the deranged individuals responsible for those artificial islands in Dubai built in the shape of a palm branch or the world map. Are beach designers, even in Onehunga, guilty of hubris?

Burke: "You could say we are definitely guilty of playing God – building coastline where there was none before, altering an historic and culturally important landscape.

"We were doing all that, but within that there lay a huge responsibility. On the one hand it could look like hubris, but on the other it was retrofitting and making good mistakes of the past."

He could have designed something overtly artificial, like the artily stacked orthogonal blocks Isthmus used for an Oriental Bay headland, but the idea was to retain the natural character of the Manukau coast, and make something that looked like it had always been there.

That meant listening to what the land was saying rather than getting wrapped up in ego and trying to dominate nature. In any case, says Burke, nature has a way of forcing your hand.

"There are physical parameters that have to work – the scale and the orientation of the beaches are things that are fixed to the Manukau."

And it'll change over time. Even before construction ended, a number of endangered dotterels moved in. Grasses and rushes should start self-seeding and soil will slowly build up on the headlands. People will use the foreshore and in doing so change it.

It's designed to last, says Burke. It can accommodate rises in sea-level of up to a metre over the next hundred years.

"Unless there's a catastrophic inundation in the next 200 years, this is permanent."

Burke likes what he's made. The TOES campaigners are happy. I liked it – not only for the near-imitation of nature but also for the audacity of even trying.

Even Patrick Reynolds, urban planning blogger and savage critic of just about anything NZTA touches, has a good word for this project.

Reynolds is generally contemptuous of NZTA's "gardening" efforts. He sees its recent enthusiasm for tasteful roadside plantings as a trick that improves the aesthetic experience of being inside a car while on a motorway, without seriously offsetting the negatives of our road-building mania.

This new foreshore though, with its beaches and open spaces and its bridge, isn't just more "lipstick on a gorilla", says Reynolds. "It's properly grunty. It has opportunities for active movement. It's great that they've finally got round to doing the rehabilitation that they were always legally bound to do. They're doing it now and they're doing it well."

All the same, says Reynolds, we should never forget that this is mitigation – fixing a horrible mistake, and NZTA and Auckland Council "shouldn't be rewarded for their f***-up. They're doing this because they cut Onehunga off from the sea!"

On Thursday I asked NZTA's regional director for Auckland if his organisation or anyone in government had ever made any sort of formal apology to the people of Onehunga for first ruining their beach, and then for fixing things up only after being forced to by a long and expensive campaign by locals. He said, "I don't know."

Cyril Skilton is looking forward to getting back down to the shore that was stolen from him in 1977. He says when people think of Auckland's waterways they think about the Hauraki Gulf and the Waitemata Harbour, "but we've got another nice one here, if it's looked after."

He's had nearly nine decades to see the way the city's going, and what it needs.

"The fact is, we're going to end up with some high-density housing. People in Auckland are going to have to live in apartments, and if you're in an apartment you need to be able to pop out and wander across the road to a park or a beach, and watch the world go by, and see a bit of green.

"It's really going to be worthwhile."

Coast. Country. Neighbourhood. City., edited by Michael Barrett (Six Point Press, $60).

CURIOUS CASE OF THE DISAPPEARING FORESHORE

Onehunga is celebrating the restoration of a shoreline lost to a motorway, but some campaigners say the NZTA and Auckland Council are on the brink of making precisely the same mistake again, and robbing the same suburb of yet another piece of coast.

Roadbuilders are planning a four-lane motorway along reclaimed land on the northern foreshore of Mangere Inlet, less than 2km east of the newly built Onehunga foreshore. On the face of it, this would once again see Onehunga cut off from the Manukau Harbour by a wide, busy road.

The planned motorway is part of the "East-West Connection" a programme aimed at reducing congestion in central Onehunga and improving truck access to the freight distribution hub Metroport.

Motorway sceptic Patrick Reynolds says it is disingenuous for the NZTA and the council to trumpet a $28m repair of an old mistake while planning to spend $1bn or more repeating it.

Confusingly, The Onehunga Enhancement Society (TOES), the very organisation that led the campaign to repair the wrongs created by the building of SH20 in 1977, are fully backing the proposed four-lane motorway on the Mangere Inlet shoreline.

Amanda Kinzett, TOES supporter and manager of the Onehunga Business Association, says on balance, putting a motorway along the Mangere Inlet shoreline is actually a good thing.

In light of the previous campaign, "it does come across as nuts, doesn't it, but the reality is everything is a horse-trade to get what's best for the community as a whole."

She says the Mangere Inlet motorway would be built on reclaimed land that's already badly degraded by years of misuse, and putting the road by the water is part of a bigger picture that includes simultaneous restoration of other parts of the coast and the unchoking of the town centre.

Reynolds doesn't buy these arguments, and believes TOES has been "co-opted" by the NZTA.

NZTA's regional director for Auckland, Ernst Zöllner, says there's a world of difference between the way motorways were built then and now.

"When we do projects we mitigate and remedy adverse effects so much better than in the 1970s."

These days, says Zöllner, the mitigation is done at the same time as the road-building. On the new motorways north of Auckland, says Zöllner, they've even installed systems under bridges that mimic rainfall on the indigeous vegetation beneath.

He said if the four-lane motorway goes ahead in the Mangere Inlet NZTA would also provide "excellent access" across it to the harbour, avoiding the kind of community disconnection caused by SH20 in 1977.

"If we add the road, we'll restore something far better."