Fire and Emergency spokesman Andrew Norris said they were called to the fire about 4.20pm. He said the fire was uncontained and they had yet to determine its size.
"There are no evacuations in place at the moment but there is one residential property that is at risk," Norris said.
"We have protected some properties in the area but at this stage our main concern is for the power supply going through that area, so crews are trying to protect the lines, but the high winds are really not helping."
Crews from Hanmer, Hanmer Rural, Culverden and Waiau are fighting the blaze. Twelve trucks are at the fire site.
NZ Transport Agency is warning people to continue to expect delays in the area.
Meanwhile crews working to contain a second fire at Motunau springs, southwest of Hanmer Springs, have clocked off for the night due to darkness and conditions.
The blaze broke out on Happy Valley Rd and began as a small fire on a 30ha plantation.
A two-man crew are monitoring overnight with crews to return in the morning.
- With RNZ
