South Island main trunk line reopens between Picton and Christchurch

State Highway 1 south of Kaikōura is on track to reopen at midday on Wednesday, says the transport agency.

The South Island main trunk line also reopened today after the rail corridor between Picton and Christchurch was damaged during bad weather.

The section of state highway between Cheviot and Kaikōura has been closed since last week.

Where the flooded Conway River took out chunks of the road near Hawkswood, the road will be down to a single lane, with a reduced speed limit and 'stop/go' traffic management 24/7.

This is likely to remain in place for several weeks while the full width of the highway is reinstated.

The risk of slips on the section of highway will be continually monitored.

Inland Route 70/Inland Kaikōura Road to the west of Kaikōura remains closed, with a detour route via State Highways 7, 65, 6 and 63.

When SH1 reopens, people are urged to travel with care and to respect the traffic management that is in place.

NZTA Waka Kotahi said the opening will be confirmed tomorrow.

Rail resumes

Freight services on the main trunk line resumed on Tuesday afternoon.

KiwiRail chief infrastructure officer Siva Sivapakkiam said heavy rain last week led to subsidence and scouring of the Conway River beneath part of the Main North Line rail corridor between Cheviot and Kaikōura.

Teams had been working since then to get the line open again.

The heavy rain meant work was needed at 42 sites along the line.

"Safety is paramount and a test train travelled over the track, confirming it was ready to go. In addition, monitoring systems have been installed," Sivapakkiam said.

Some speed restrictions will be in place while work to further strengthen the line is carried out.

"Re-opening the line quickly, especially while the road remains closed is a positive outcome for the South Island supply chain, and for KiwiRail's role as an essential and valued part of New Zealand's freight transport system."