Cost of repairing Auckland Harbour Bridge expected to be $1m to $2m

The damaged strut on the Auckland Harbour Bridge. Photo / Supplied

The cost of repairing the Auckland Harbour Bridge after a truck toppled over and damaged a load-bearing strut on September 18 is expected to come in between $1 million and $2m.

Waka Kotahi NZ Transport Agency said it is still finalising the costs, which include designing, fabricating and installing the temporary and permanent beams, as well as labour and traffic control.

The bridge was closed after a freak 127km/h gust of wind blew a truck into a metal support strut, damaging the bridge and forcing engineers to close four of its eight lanes.

The powerful winds also tipped another truck on its side.

Four of the bridge's eight lanes were closed, bringing chaos to the city's road network that evening as motorists took hours to make it home.

A second bout of strong winds barrelling through Waitematā Harbour at close to 100km/h brought more delays to motorists a few days later when authorities temporarily closed the bridge.

The permanent fix included a 22.7 metres long strut reaching from the bridge over-arching to the bridge deck. It was fabricated from NZ-made steel in Whangārei as a like-for-like replacement.

A truck crashed on the bridge causing structural damage. Photo/Supplied

The bridge was restored to 100 per cent capacity on October 6.

Waka Kotahi said its overall expenditure on emergency works - repairing damage from slips, floods, rockfalls etc - for state highways in the 2019/20 financial year was $75.2m.

It gave an example for comparison - repairing and rebuilding SH4 between Whanganui and Raetihi following a major slip in October 2019. So far, $5.2m has been spent and it will cost a further $15.3m on the permanent reinstatement of SH4.