Tasman scrub fire largely contained

A scrub fire burning south of Murchison on State Highway 65 is largely contained.

Four helicopters and three ground crews were working on the fire, burning on conservation land on the northern side of the Shenandoah Saddle in the Tasman District.

It was estimated to have burned 20 hectares of conservation land since it began on Monday morning.

Fire and Emergency (FENZ) district manager Grant Haywood said crews were completing containment lines around the fire and dealing with hotspots on Tuesday morning.

He said the fire was burning in steep terrain that was difficult for ground crews to access. No properties were threatened.

FENZ West Coast district manager Myles Taylor told Midday Report they expected to have it under control by the end of the day.

They were looking at imposing a prohibitive fire season in the inland Buller zone on the West Coast, he said, which would be a first "in many, many years".

"It just indicates how dry conditions have got out there and that people need to be really vigilant if they are having a fire.

"We've had reduced amounts of rainfall across the South Island - so South of Canterbury, parts of Otago, the West Coast unusually, Southland - they're all experiencing lower rainfalls than normal and as a result the fire danger is elevating quite quickly."

SH65 between Murchison and Springs Junction reopened to one lane under traffic management.

A rural fire investigator was heading to the scene on Tuesday.

Haywood said the fire was 80 percent contained by nightfall and a crew remained on site overnight to monitor the situation.