The homeowner was rescued by police. She was been taken to hospital with suspected smoke inhalation.
A St John spokesman said three people had been taken to hospital in relation to the fire.
One was rushed to Christchurch Hospital in a serious condition, believed to be related to smoke inhalation. Two others with minor conditions were also hospitalised, the spokesman said.
Residents who have been evacuated from the farms and lifestyle blocks have fled with pets, clothes and prized possessions.
Locals also helped rescue horses from a property ablaze.
Matt Smith, who lives across the road from the blaze, says locals shut Weedons Ross Rd and shifted the horses across to another paddock and safety. Three were stallions never handled before.
"We've been lucky," Smith said.
However the blaze is far from under control.
Heavy northerly winds are fanning it as the temperature remains above 30C.
There are fears it could spread and threaten a new subdivision.
A welfare centre set up in West Melton at the West Melton Community Centre had closed, but would be reactivated if needed.
Smith has a caravan loaded up and hooked to his car ready to flee. His power went off at 3.09pm as the fire engulfed a power pole.
The fire has come within metres of the road. Locals with buckets are dampening hot spots.
A drop in wind has helped save properties and helped fire crews get a foothold on the blaze, locals say.