NZTA project Roading

A milestone for contracting

Whatever it meant to the people of Kaikoura and North Canterbury, the re-opening of SH1 between Christchurch and Picton on December 15, 2017, albeit only during daylight hours, was a public relations coup for the entire South Island civil contracting industry. Hugh de Lacy explains.

A busload of workers and contractors being taken back into Kaikoura from the big we-did-it party at the racecourse south of the town was applauded all the way by not only local residents delighted at their release from isolation, but by tourists and camper-vanners who somehow knew who was aboard, and pulled over to cheer them through.

It was as if all their Christmases had come at once, and they were eager to salute the workforce, which had peaked at around 1700 people from 100 organisations, for reconstructing their beautiful road just one year, one month and one day after the entire eastern seaboard from Cheviot north had been smashed by a 7.8 magnitude earthquake near midnight on November 14, 2016.

The quake had put a stranglehold on the entire South Island economy through which people and supplies had to be squeezed along inland roads never designed to take the volume of traffic that now travelled them.

The lifting of the barricade at Waipapa Bay, about 20 kilometres north of Kaikoura, at 1pm just 10 days before Christmas, unleashed a torrent of traffic that had grown to the hundreds waiting at the southern end of the blocked highway to get through.

The quake had wrecked main highway and Main Trunk railway alike, and was the most physically devastating of the succession of upheavals that began in Canterbury in September 2010, killed 185 people and flattened much of Christchurch five months later, before culminating – hopefully – with the Kaikoura-centred biggie that killed three people and destroyed all land-based communications.

It incidentally gave the capital city of Wellington a big fright, doing enough damage there to force the demolition of a dozen high-rise buildings.

Given the social and economic impact of the quake on the South Island’s no less than Canterbury’s and Kaikoura’s economy, it was perhaps unsurprising that the people who repaired the damage should be welcomed like heroes where they were recognised.

Though much excitement had greeted the tentative opening of the railway on September 15, it was the reinstatement of the road that seemed really to signal the end of the year-long isolation.

New Year’s Eve in Kaikoura was once again party-central, with the main street of the town packed with tourists and holiday-makers.

The scale of the devastation left by the quake can best be appreciated in the fact that more than one million cubic metres of slip material had to be cleared off the road by the North Canterbury Transport Infrastructure Recovery alliance (NCTIR), which comprises the NZ Transport Agency and Kiwirail, along with the big contracting firms of Fulton Hogan, Downer, HEB Construction and Fletcher Construction’s Higgins subsidiary.

A total of 194 kilometres of road and 190km of rail was put out of action, and between Cheviot and the Clarence River there were no fewer than 85 landslides, 1500 damaged sites (200 of them with major issues), more than 100 structures damaged (nine of them severely), 20 rail tunnels badly damaged, and Kaikoura’s harbour floor had lifted six metres, destroying the region’s core whale-watching tourism infrastructure.

To Tim Crow, the NZ Transport Authority’s earthquake recovery manager, a key element in organising the recovery was the rapid response of first the local then the big contractors.

No doubt buoyed by the experience of reacting to the Christchurch catastrophe, the partners in the NCTIR came together rapidly to first measure the damage – the biggest slips contained up to 300,000 cubic metres of spoil each – and then to settle on a strategy for repairing it, Tim says.

The main problem initially was lack of access to the multiple sites, and the broad approach was to get the big contractors working at either end of the 200km stretch of road, with the locals slugging north and south from Kaikoura.

Once the clearing of the inland road had broken Kaikoura’s abject isolation – only the local airport was still able to function, and regular flights were quickly established between there and Rangiora – it became clear that a haul road would have to be constructed north out of the town.

This wasn’t completed until September, just as the first freight train was passing through from Picton to Christchurch.

It was clear too that a big seawall was going to be needed at Ohau Point, but it wasn’t until mid-October that the construction teams could gain access to it.

A month after that, on November 14, the Kaikoura marina opened, and the trickle of tourists brave enough to tackle the crowded Inland Kaikoura road could get their look at the whales desporting themselves off the ravaged coast.

In Kaikoura itself the quake had lifted South Bay and the harbour floor by just over a metre, and 22,000 cubic metres of spoil had to be dredged.

The government put up an immediate $5.7 million to restore the harbour to full functionality, while the tour operators, Ngai Tahu’s Whale Watch and the privately-owned Encounter Kaikoura, each funded $900,000 worth of future expansion to accommodate bigger boats.

By the time of the October reopening, the harbour had not only been fully dredged but four new Whale Watch berths, an Encounter Kaikoura jetty and a tender jetty for visiting cruise ships had been constructed, and the Coastguard slip restored.

Within a month of the quake, then Transport Minister Simon Bridges had put the bill for the complete recovery at between $1.4 billion and $2 billion, to be funded by the government, though only about $500 million of that had been spent by the time SH1 reopened.

To clear the way for the work, the then National-led government rushed emergency legislation through Parliament in December 2016 to cut through what would otherwise have been a tortuous and time-consuming consenting process.

It also quickly became apparent that Kaikoura’s battered infrastructure could not provide housing for the army of workers, Tim says, so a temporary accommodation village was built to house 300 workers.

By the time the road reopened more than two million work-hours had been expended on site-clearing and construction.

In the process no fewer than 200 archaeological sites were discovered and explored.

A huge amount of the early work of clearing crumbling cliff-faces from the top down had to be done by helicopters with sluice-buckets carting millions of litres of sea-water, and often coordinated with teams of abseilers on the ground.

And the job is by no means finished yet: Tim Crow estimates it’ll be July this year at least before the remaining work, including the construction of no less than 2.8 kilometres of sea-wall, will be finished.

And perhaps there’ll be a party to mark that too, but it’s unlikely to exceed the undisguised joy that the re-opening of the Picton-Christchurch highway brought to the Kaikoura locals over Christmas and New Year.

This article first appeared in Contractor February 2018.

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