Trees had caused the majority of the cuts to supply, said Mr Marsh.
"Many of the power cuts could have been avoided if people had contacted suitably qualified tree trimmers to have their trees cut or trimmed before they caused a problem," he said.
Mr Marsh said more than 70 field staff were working to restore power in Wairarapa, where most of the damage was sustained to Powerco's network.
Power cuts affected all Wairarapa as severe gales, reaching 170km/h in exposed areas, downed power lines.
About 80 people attending an emergency management training conference at the Copthorne Hotel and Resort Solway Park were left in the dark about 7pm on Monday.
It was quite ironic, said Jerry Crump, the general manager.
"They were good people to have in a power cut."
The kitchen had gas and an emergency light so food was able to be cooked.
"They all had dinner with candles on the table. I think they kind of enjoyed it."
The power came back on about 10.30pm.
The water supply in Greytown dwindled due to the power cuts. Reserve tanks were starting to run out just before power came back on yesterday morning.
"They got the power back on as it was running out; it was quite lucky," said Mark Allingham, group manager infrastructure services at South Wairarapa District Council.
On Monday night, the main water and emergency bores went out so supply was running on what remained in the pipes.
Mr Marsh urged members of the public to keep clear of any damaged power lines and report them to Powerco on 0800 272 727.
He reminded people that live power lines can kill and to stay clear.