Auckland Harbour Bridge middle lanes 'not safe' after crash but no risk of collapse

Saturday, 19 September 2020

A passenger captured the moment a truck almost toppled on Auckland's Harbour Bridge on September 18.

Vehicles will not be able to use the four centre lanes of Auckland Harbour Bridge for weeks, but there is no risk of collapse, officials say.

Brett Gliddon, Waka Kotahi New Zealand Transport Agency’s (NZTA) general manager of transport services, on Saturday said a truck that hit the bridge had severely damaged one of its upright struts.

A new strut must be made to replace the damaged one and until then, it was not safe for vehicles to use the middle lanes.

NZTA general manager of transport services Brett Gliddon says it could be weeks before all lanes on Auckland Harbour Bridge reopen.

The news comes as motorists faced a second day of gridlock after two trucks were caught up in a 127kmh wind gust, and one crashed, about 11.10am on Friday.

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It is estimated the piece of metal require to fix the bridge weighed tonnes.

Gliddon said the struts were designed to shear away if hit, so as not to damage other parts of the bridge.

The centre lanes could be opened to lighter vehicles if a temporary solution could be found, he said, however it could be up to a week before that happened.

A temporary solution would involve installing more steel onto the bridge to minimise the load on the damaged strut.

Engineers were working on the bridge to see if there was any damage where the broken strut was attached.

Asked why there were no spare parts immediately available, Gliddon said it was a “pretty big piece of metal” weighing tonnes.

The damaged strut went from the road surface to the very top of the bridge, he added, and was about 400-500 millimetres thick.

Bolts were sheared off the bottom of the damaged strut, leaving it detached at the bottom.

'Each individual part of the bridge has its own design and shape so it’s not feasible to carry a complete set of parts for a harbour bridge.'

The harbour bridge is made up of several structures, and the outer “clip-on” lanes that remain open operate “completely independently” from the main structure.

Gliddon said no structure on the bridge had been hit like this before.

Traffic on the northern, southern and northwestern motorways was severely clogged well into the evening following the incident.

He asked North Shore residents who typically work in the city to instead work from home, or use public transport.

The western ring route was available for those who needed to drive, but he warned “with half of the capacity out of the bridge, the rest of the network could see some congestion”.

Auckland Transport spokesman Mark Hannan said it did not have any additional buses as they were replacing trains during rail replacement on the Onehunga and Southern lines.

However, it was confident it would cope with increased patronage as passenger capacity was sitting at about 50 per cent of “normal pre-Covid levels”.

It asked people to travel during off-peak hours if possible, where passengers would receive a 30 per cent off-peak fare discount.

Sarah Geard, AA’s senior infrastructure advisor, said the lane closures were a “really worrying situation”.

“Auckland is just starting to get back on its feet, and this could be another awful blow.

“The only comfort is that traffic levels are down as a result of Covid-19 – so the impacts won’t be quite as disastrous as they could be.”

She said it underlined the need to speed up the conversation about an alternative harbour crossing.

“It’s unacceptable for one, relatively minor incident to have this much impact – Auckland needs a more resilient network,” she said.

Traffic heading over the Auckland Harbour Bridge from the CBD on Saturday at 9.30am.

After the crash, traffic delays continued well into Friday evening on both SH1 and the Western Ring Route, and also hampered motorists’ progress on Saturday.

Travellers from the Hibiscus Coast faced an extra 20 minutes on their journeys into the city centre than normal, while motorists from West Auckland will be stuck in traffic for about an hour.

The New Zealand Transport Agency’s (NZTA) Auckland traffic dashboard showed it would take motorists from Silverdale about 40 minutes to reach the city, while travellers from Helensville via Upper Harbour Highway (SH18) and SH1 would reach the CBD in about an hour and 10 minutes.

The AA’s roadwatch map showed heavy congestion in, out and around the city centre.

Resident Nigel Horrocks, who lives in an apartment on Karangahape Rd overlooking the motorway, said vehicles were continuing to “crawl” towards the Harbour Bridge about 1pm.

“This is extremely unusual, it is what you would expect during rush hour on a weekday. It does not bode well for another few weeks.”

On average, more than 170,000 vehicles cross the bridge on weekdays.