More homes in Christchurch are being demolished or have been evacuated, as the death toll rises to 147 following Tuesday’s powerful 6.3-magnitude earthquake.
Police say there are grave fears for another 200 people who are unaccounted for and warn that more bodies will be removed from collapsed buildings in the CBD today.
Rescuers say they are still looking for survivors but are losing hope because no-one has been found alive since Wednesday.
More than 600 rescue workers are scouring the city and hardest-hit suburbs, where broken water and sewage pipes, toppled power lines and ruptured gas mains have made large areas uninhabitable, forcing thousands to flee.
In the devastated eastern suburbs nearest the quake epicentre, hundreds of homes are marked with red tape for demolition, while others have been evacuated due to the danger of falling rocks.
Power has now been restored to most of the city but many of its 390,000 residents are without water and relying on supplies brought by tanker.
Officials said more than 62,000 homes have no water supplies and 100,000 properties are without sewerage, while 800 portable toilets were being put in place to help ward off the threat of disease.
Earthquake recovery minister Gerry Brownlee says rebuilding plans are already underway for the ruined CBD, but much of the financial district may be sealed off for months as a “huge demolition effort” of up to a quarter of the buildings begins.
Early estimates of insurance losses have ranged from $3 billion to $12 billion.
“When we do rebuild the type of building will have to pass an economic test for future use and it will have to meet pretty stringent (building) code requirements,” Mr Brownlee said.
“That doesn’t deter us from doing that, the prospects for this city are quite bright there are not many other cities that get to completely rebuild.”
In the CBD, the search is concentrated on a finance company office block, the city’s landmark cathedral and a the Canterbury Television (CTV) building, which housed an English language school.
More than half of the dead have come from the ruins of the CTV building.
About 61 people, including 26 Japanese and 13 Chinese students, attended an English language school in the same building where floors pancaked down on one another.
Mayor Bob Parker says of the 1,000 buildings in the CBD, only 600 are safe to enter.
“Twenty to 25 per cent of the buildings that we’ve visited have had to be red-stickered; that is, they are declared to be in danger of imminent collapse or are not safe,” he said.
“So that’s an incredibly high proportion of severely damaged buildings in the central business district.”
Aftershocks are disrupting the recovery progress and Phil Parker from New Zealand’s rescue team says the going is tough.
“Once we go to search the buildings, we’ll go in as teams,” he said.
“We’ll have a safety officer that’s based outside and so we’re evaluating those buildings all the time we’re in there.
“Obviously we’re getting aftershocks so we’ve got to be prepared for those, but there’s always that danger of the buildings coming down on us.”
Navy ship HMNZS Canterbury is sailing to Wellington this morning to load up with disaster relief supplies for Christchurch.
Earlier, prime minister John Key said the disaster “may be New Zealand’s single most tragic event” and asked for two minutes silence at 12:51pm on Tuesday, to a mark a week since the quake.
He called it an opportunity for all New Zealanders to express their deepest sympathy.
The earthquake currently rates as New Zealand’s second deadliest disaster, after a 1931 tremor killed 256 people in the Hawke’s Bay region.