A large wildfire on the shores of Canterbury's Lake Pukaki is controlled but not contained, Fire and Emergency says.

The fire covered about 50 hectares.

Fire crews have partially opened Canterbury's State Highway 80 to allow people stranded at Mount Cook village to leave. The road had been closed since Monday afternoon.

A FENZ spokesperson said drivers should expect delays and poor visibility due to smoke.

Four properties, two of which were vacant, were evacuated as a precaution on Monday night.

The two affected owners would meet with the incident controller on Tuesday, FENZ said.

A helicopter and heavy machinery have joined multiple ground crews Tuesday morning to try contain the fire.

The fire died down overnight but there were at least ten hectares where flames were still ripping through wilding pines, grass and slash piles.

Main image (RNZ/Supplied/ Scott Aronsen): Two homeowners will meet with the FENZ incident controller this morning.