Rain hampers efforts to clear slip blocking SH1

File photo / The Aucklander

Kiwirail says it could be days before the resumption of its TranzCoastal passenger train service between Christchurch and Picton following the major landslide south of Kaikoura.

State Highway 1 and the rail line were closed after around 15,000 cubic metres of rock and soil crashed down from the surrounding hillside late on Friday night.

Experts described the 100m-long slip between two road bridges as the biggest in years which could take days to clear because of the hazardous working conditions.

Heavy rainfall and not any recent earthquake activity is being blamed for the slip.

Cars are being diverted on to the inland Kaikoura Road while heavy vehicles are being re-routed via the Lewis Pass.

But Kiwirail said today it had no alternative but to temporarily suspend its TranzCoastal service and was unable to provide a bus replacement.

"Cancelling the service until the slip is cleared was our only realistic option," said Kiwirail spokeswoman Deborah Hume.

"We apologise for the disruption to our customers but as the road is closed as well we cannot run a coach replacement and hope to keep even remotely to timetable or meet the Interislander ferry."

The only alternative route for coaches, via the Lewis Pass and Wairau Valley, would almost double the journey time and miss out most stops along the route.

"We are working with New Zealand Transport Agency and other transport providers to see when the service will be up and running again, which may take several days.

"We will make an announcement about resumption of the service as soon as we can.

"In the meantime we are contacting all the passengers we can to offer alternative dates or a refund on their fare."

She said the TranzAlpine, which runs daily between Christchurch and Greymouth was unaffected.

- NZPA