State Highway 1 has re-opened following a train derailment in Mercer, south of Auckland, this morning.
The New Zealand Transport Agency confirmed that traffic was flowing freely by about 3pm.
The southbound lane was closed after four wagons derailed on a north-bound train, with two obstructing the motorway, about 3.20am.
Traffic was diverted for more than 11 hours.
Two railway lines were also forced out of action. The first was reopened at 2.30pm and the second was expected to be in use by 6.30pm, KiwiRail communications manager Kimberley Brady said.
‘‘It impacted on our freight operations but we were very happy to be able to get it cleared and repaired within a day.’’
KiwiRail will conduct a full investigation into the cause of the derailment.
''We'll (also) have to check whether any track repairs will need to be made,'' Brady said.
''I'm not going to speculate on causes. It could be the track. It could be the rolling stock. Until we do the full investigation we don't know.''
The Transport Accident Investigation Commission would also investigate.
- © Fairfax NZ News
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