Mr Macmillan said some customers were still without power in Dargaville, the worst affected area across the network, but restoration was being worked on now.
There was an interruption on the main line from Maungaturoto supplying Ruawai.
"We have transferred most customers to alternative supplies but due to the weather there have also been interruptions to those power supplies."
Also interruptions on the Dargaville Coast and up to the Waipoua Forest.
"The reason it is hard to finalise a figure is that with this on-going wind we are having rolling outages," he said.
"We need people to remain patient as some customers could be without power for some time today."
He said a number of crews were out in the field this morning doing a great job and it was hoped everything would largely back to normal by the end of today but there could be some lingering faults into Friday.
Meanwhile, Top Energy spokeswoman Philippa White said about 2000 households around the Far North were without power overnight.
The outages were in small pockets all over the district which meant repairs were time-consuming with line crews having to travel to each fault, remove branches and debris, repair lines and in some case replace poles.
Repairs could take until the end of the day, she said.
Areas still without power at 8am this morning included the area between Hukerenui and Maromaku, Pakaraka, Rawene, Kohukohu and Horeke, Mangamuka, the south side of Whangaroa Harbour, Totara North and Herekino. Many other small areas are affected.
* To report faults phone 0800 10 40 40 (Whangarei/Kaipara) or 0800 867 363 (Far North). Remember to stay clear of lines and treat all lines as live at all times.
