Four days on from Tuesday's earthquake, half of Christchurch still has no mains water supply, but power has been reconnected to just under 80 percent of the city.
Search and rescue staff have completed their initial grid search of the city centre.
The death toll from the disaster is well above 140, but about 200 people remain unaccounted for.
The lines company, Orion, says in any damaged home or building, an electrician should inspect the wiring before people switch power on at the mains.
There are desalination units operating to produce clean water in New Brighton and Lyttelton.
Water is also available at the welfare centres at Welfare centres around Christchurch and numerous other sites.
There have been two aftershocks since midnight - a magnitude 3-point-4 at five to two this morning with a depth of 9 kilometres, and another at 4.19 measuring 3-point-2, at 8 kilometres deep.
Teams of engineers have begun the long job of assessing building safety in the city.
They have closed nearly two hundred homes and buildings for safety reasons.
There are red stickers on ten buildings in the central city, 96 homes in Christchurch, and 90 buildings in Lyttelton.
The Hotel Grand Chancellor on Cashel Street is still cordoned off for fear of collapse, constraining emergency operations nearby.
The hotel is listing and has been rotating on its foundations.
The Lyttelton tunnel is still closed to all but emergency traffic, and a cordon remains around the central Christchurch city area.
A field hospital has been set up by Australian doctors and nurses in Christchurch.
The centre is in one of the worst-affected areas of the city, at Cowles Stadium, from where 170 quake refugees were moved yesterday because of sanitation worries.
A nurse and midwife who'll be working there, Angie Jackson, says it's for people who would normally see a family doctor or antenatal caregivers.
"It's not actually intended to replace or act as a hospital as such, it's really because the general practitioner facilities in this area are not particularly operational and really the whole idea of this centre is to be a primary health centre."
More than three hundred Australian police officers are now in Christchurch to provide support.
They've been sworn in and will work alongside police from Christchurch and others who have been redeployed to the city from elsewhere in New Zealand.
Inspector Derek Erasmus says the Australian officers were welcomed by the Police Commissioner.
Our local staff have over a third of us who are badly affected by the in terms of missing relatives, injuries and severely damaged houses, so the influx of our Australian colleagues in fantastic.
Derek Erasmus says starting the police now have a significantly bigger presence on the streets of Christchurch.