Fire crews will today attempt to dampen "quite a few hot spots" remaining from the large scrub and grass blaze that ignited yesterday south of Rotorua.
A northern fire communications centre spokesman said a front loader would be brought in today to help "dig out" some of the more entrenched hot spots.
He said three Taupo rural firefighters stayed overnight at the scene to make sure the blaze did not reignite.
Te Toke Rd has been closed.
Fire Service Central-Lakes assistant area commander Hamish Smith said around 14 rural fire personnel would help dampen the hot spots today.
He said by the time the blaze was controlled, it was too dark to determine the possible cause.
A fire safety investigator will be on scene this morning.
About 45 firefighters from Rotorua, Taupo and around the region - as well as three helicopters with monsoon buckets - attended the fire, which broke out just before 4pm.
The fire was between the Ohaaki Power Station and the banks of the Waikato River, covering 4ha.