Powerco operations manager Phil Marsh estimated it would cost at least $2 million to repair the devastation done to the electricity infrastructure. He said the damage was complex which meant work was slower than they thought it would be.
"People are saying it's the worst snowstorm in that region since 2002. On that occasion our network received massive damage - and this is just as bad.
"The team working on the storm damage have been working extremely hard in difficult conditions. We have more than 220 additional crew working in the field to restore power across the Western area."
Power was restored to Mangaweka on Sunday although some rural and remote areas remained without power.
Marsh said they were offering assistance to those still without power.
"We have identified those customers we anticipate will be worst affected. While some may have their own generators, our staff are contacting everyone to see if they need assistance.
"We are gradually mopping up problem areas in Whanganui, Wairarapa, Manawatu and Taranaki.
"Good progress is being made restoring high-voltage supply. However, some people might still have low-voltage problems."
Marsh urged people to remain wary of downed lines. Anyone coming across them should keep well clear and call emergency services on 111 or Powerco on 0800 27 27 27. For information visit the website www.powerco.co.nz or call their retailer.
Road closures
Canterbury
SH 82 Kurow to Waimate - Ice - All restrictions now lifted.
SH 8 Twizel to Fairlie - Ice - Road users are advised to take extra care.
SH 80 Ben Ohau to Aoraki Mt Cook - Ice - Winter driving conditions. Road users are advised to take extra care.
Otago
SH 8 Clarksville to Raes Junction - Snow and Ice - Winter driving conditions. Road users are advised to take extra care.
SH 90 Raes Junctions to Mcnab - Ice - Winter driving conditions. Road users are advised to take extra care.
SH 87 Middlemarch to Outram - Black Ice - Road users are advised to take extra care.
SH 87 Kyeburn to Middlemarch - Snow and Ice - Winter driving conditions. Road users are advised to take extra care.
SH 85 Kyeburn to Palmerston - Snow - Winter driving conditions. Road users are advised to take extra care.
SH 8 Tarras to Omarama (Lindis Pass) - Snow - Chains essential - closed to towing vehicles.
Lindis Pass - Snow showers are expected to clear this afternoon. From 9am to 2pm today, 2 to 4cm may settle on the top of the road.