Paul Turner, Fire and Emergency New Zealand's national manager response capability, said the use of aerial services is standard when fighting vegetation fires.
"Aircraft are used to deliver large quantities of water and to access areas that are difficult for ground-based resources to reach," he said.
Rural firefighters Deon McKay and Luca Ropper manning a pump on the fringes of the Tasman bush. Photo / Mark Mitchell
"In extremely dry conditions, such as occurred during the Tasman fires, there is also a greater risk of vegetation fires spreading through ember transfer.
"This necessitates significant fire breaking and the creation of containment lines to keep the fire from spreading."
Costs as of May 5 released through the Official Information Act revealed FENZ spent $11,826,436 in total tackling the blaze.
Operational plant and equipment hire, and external firefighting services were the second and third highest costs - $2,804,310 and $1,485,243 respectively.
Employee costs totalled $1,027,048, with volunteer payments amounting to $697,060 for the fourth and fifth-highest costs.
Most volunteers were not paid for day-to-day work but when deployments became extended over a period of time, provisions led to payments being received in some cases.
It took 29 days for the fire, which spanned an area greater than the 2017 Port Hills fires, to be brought under control.
Tasman Fire
Apart from size, Turner said it was hard to compare fires with one another.
In addition to FENZ, Tasman District Commander Superintendent Mike Johnson said police spent $264,988 during their response.
He said 223 staff responded between February 5 and 27, but costs were not separately recorded.
Meanwhile, MPI spent $414,729 in relation to the Tasman fires, acting director of readiness and response services Angela Brownie said.
Staff costs amounted to $268,595 for the 52 MPI staff and contractors, including specialist veterinarians and animal welfare experts.
Travel, accommodation, property and other costs amounted to $50,783, with $95,351 spent on support costs.
MPI said support costs was funding which went to the Tasman District Council and the Rural Support Trust to assist them in their work on the ground.
The Nelson fires with the start point circled in red. Photo / Mark Mitchell
Nelson City Council said their main cost was associated with staff time but it was difficult to determine the total cost.
Communications manager Paul Shattock said the best way to articulate the city council's expense was through the time cost.
"Which was approximately 20 per cent of the total staff time during February was directed to assisting with the Pigeon Valley Fire response," he said.
An independent operation review is being done into the fires. Its findings will be considered to what lessons can be drawn from the huge response.
The third-largest plantation forest fire in New Zealand history, Turner said the public responded well to FENZ's requests to evacuate their homes and remain clear of cordons.
"We also appreciated the patience of those affected by the fires and the support we received from the public throughout the incident.
"The Tasman fires highlighted the dangers of vegetation fires and the importance of being prepared in the event of a fire."
Police looked into the cause of the blaze but handed the inquiry over to FENZ, which is still to complete its investigation.
