The main outages were reported in parts of Hastings and Havelock North where power went off about 7.15am before returning just after 8am, affecting about 5000 users.
There were also power surges reported in Greenmeadows, Flaxmere and Napier South, and this may have led to water being cut off in large parts of the Hastings district, and schools throughout Flaxmere being closed.
In Hastings the water was off for about an hour from 7.10am, but the timing meant hundreds of children got a day off after the Ministry of Education asked all Flaxmere schools to close for health and safety.
A Hastings District Council spokesperson said the problem occurred when the power first went off and supply was back up and running by 8.05am but pressure was low for a short period of time until it built up again.
Council was advised the water was off in Flaxmere, St Leonards, Fernhill and Omahu due to a power surge.
The power surges that accompanied power cuts yesterday morning meant the electronic system at the Frimley bore powered down and when the power came back on it did not automatically re-start. It had to be started manually at the site.
The spokesperson said an added complication was that the major water works going on along Heretaunga St meant that line was closed, so water could not be pumped back from Hastings to the affected area.
Flaxmere Primary School principal Robyn Isaacson said the water was still off when school opened at 8.30am, but had been restored by 9am.
She said it was a legal requirement of the Ministry of Education to close schools if there was no water and no working toilets.
"About 400 of our 500 pupils went home but we still have 100 kids that were not able to go home and we will carry on as normal with them."
All staff had remained at the school to carry on teaching the children who had remained.
Other schools and pre-schools to close due lack of water included Irongate School, Flaxmere College, Kimi Ora Community School, Peterhead School and Te Kāinga Pōtiki ō Pāharakeke.