People are being warned to be careful as electricity is restored to Christchurch.
Power was knocked out to most of the city following a devastating earthquake on Tuesday. Lines company Orion says just under 80% of the city had power by Friday night.
Orion chief executive Roger Sutton warns that fires can start accidentally as electricity is restored.
This has happened before when overturned heaters are turned back on, or items are left on a stovetop that has its elements switched on.
Mr Sutton says if houses are damaged, people should be getting an electrician to inspect the wiring before switching the power on at the mains.
The Fire Service says it has responded to nearly 200 callouts in Christchurch since Thursday, three of which were fires caused by electricity being turned back on.
Eastern suburbs badly affected
Mr Sutton says power has been restored to most of the west of greater Christchurch and rural areas.
However, areas in the east such as Dallington, New Brighton, the central business district and the Sumner-Clifton areas will take longer, and weeks of repair work still lie ahead.
Mr Sutton says workers are discovering more complex faults as they go and restoring power to the CBD could take even longer as there are so many damaged buildings to make safe.
High-voltage cables damaged
Damage to four high-voltage underground electricity cables in Bromley is hampering repairs to the city's power system.
Roger Sutton says repairs to the oil-filled cables will take many weeks, so the company has decided to build a 3km overhead line from a substation in Bromley to New Brighton.
Mr Sutton hopes the new line will be built within a week.
Desalination units set up
The Army has installed desalination units at New Brighton and Lyttelton to allow more people to get access to clean drinking water
The units take water from the sea and purify it, making it safe to drink.
Lieutenant Michael Clulow says they're expecting to distribute about 40,000 litres of water on Friday.
He says it is the first time the units have been used in a humanitarian or civil defence role.
Meanwhile, the Port of Lyttelton is resuming limited operation with a bulk fuel tanker and an LPG gas tanker expected on Saturday.