Christchurch's central city and eastern suburbs were badly affected, with damage to buildings and infrastructure already weakened by the 2010 Canterbury earthquake and its aftershocks.

The increased liquefaction caused significant ground movement, undermining many foundations and destroying infrastructure, damage which "may be the greatest ever recorded anywhere in a modern city".

[32] The central business district (CBD) experienced PGAs in the range of 0.574 and 0.802 g.[33] As a comparison, the 7.0 Mw 2010 Haiti earthquake had an estimated PGA of 0.5 g.[30] The acceleration occurred mainly in a vertical direction,[20] with eyewitness accounts of people being tossed into the air.

[35] The acceleration experienced in February 2011 would "totally flatten" most world cities, causing massive loss of life; in Christchurch, New Zealand's stringent building codes limited the disaster.

"[67][68] Of the 3,000 buildings inspected within the four avenues which bound the central business district by 3 March 2011, 45% had been given red or yellow stickers to restrict access because of the safety problems.

[82] The west wall suffered collapses in the June 2011 earthquake and the December 2011 quake[83] due to a steel structure – intended to stabilise the rose window – pushing it in.

[105] On 7 March, Prime Minister John Key said that around 10,000 houses would need to be demolished, and liquefaction damage meant that some parts of Christchurch could not be rebuilt on.

[129] KiwiRail also delayed 14 March departure of its Interislander ferry Aratere to Singapore for a 30-metre (98 ft) extension and refit prior to the 2011 Rugby World Cup.

[144] A full response management structure was put in place within minutes of the quake, with the Christchurch City Council's alternate Emergency Operations Centre re-established in the City Art Gallery and the regional Canterbury CDEM Group Emergency Coordination Centre (ECC) activated in its post-earthquake operational facility adjacent to the Canterbury Regional Council offices.

Both COGIC, French Civil Protection and the American USGS requested the activation of the International Charter on Space and Major Disasters on the behalf of MCDEM New Zealand, thus readily providing satellite imagery for aid and rescue services.

NSW Task Force 1, a team of 72 urban search and rescue specialists from New South Wales, Australia, was sent to Christchurch on two RAAF C-130J Hercules, arriving 12 hours after the quake.

The crew of the Navy ship Canterbury, in Lyttelton harbour at the time of the earthquake, provided meals for 1,000 people left homeless in that town,[172] and accommodation for a small number of locals.

... We will be doing everything we can to work with our New Zealand family, with Prime Minister Key and his emergency services personnel, his military officers, his medical people, his search and rescue teams.

The scale of the destruction all but defies belief when we can appreciate only too well how difficult it must have been struggling to come to terms with last year's horror ... Our deepest sympathy and constant thoughts are with you and all New Zealanders.

"[207] Barack Obama, President of the United States, issued a statement from the White House Press Office on the disaster by way of an official announcement that "On behalf of the American people, Michelle and I extend our deepest condolences to the people of New Zealand and to the families and friends of the victims in Christchurch, which has suffered its second major earthquake in just six months... As our New Zealand friends move forward, may they find some comfort and strength in knowing that they will have the enduring friendship and support of many partners around the world, including the United States."

[219] New Zealand's governor-general, Sir Anand Satyanand, attended, along with John Key, Bob Parker, and a number of local and international dignitaries.

[220] Australia's official delegation included Governor-General Quentin Bryce, Prime Minister Julia Gillard, and Opposition Leader Tony Abbott.

[224][225] A minute's silence was held at 12:51pm, and the names of all the victims were read aloud by Christchurch residents and first responders, before a wreath laying ceremony at the memorial.

The Commission examined issues with specific reference to the Canterbury Television (CTV), Pyne Gould Corporation (PGC), Forsyth Barr and Hotel Grand Chancellor buildings.

[citation needed] The commission was chaired by High Court judge Justice Mark Cooper with support from two other commissioners, engineers Sir Ron Carter and Professor Richard Fenwick.

Approximately 450 fully serviced mobile homes would be located on sites across the city including Canterbury Agricultural Park and Riccarton Racecourse.

This meant most secondary schools in the city had closed early that day and most students had returned home before the earthquake hit, coincidentally limiting potential casualties.

[243] 163 primary and secondary schools were affected by the earthquake, most of which were closed for three weeks; 90 had full structural clearance and were able to reopen, 24 had reports indicating further assessment and 11 were seriously damaged.

Site-sharing plans were made to enable affected schools to relocate, while 9 "learning hubs" were established throughout the city to provide resources and support for students needing to work from home.

[264] AMI Stadium was going to host the rugby league ANZAC Test, however, on 4 March it was announced the match would be moved to Skilled Park on the Gold Coast.

[282] EQC cover for domestic premises entitles the holder to up to NZ$100,000 plus tax (GST) for each dwelling, with any further amount above that being paid by the policyholder's insurance company.

[285][286] The Accident Compensation Corporation (ACC) announced it would be the largest single event they had paid out for, with an estimated 7,500 injury claims costing over $200 million.

[293][298] It is thought that natural disasters, such as earthquakes, are able to induce these positive effects because they affect an entire community, in comparison to an event that targets only an individual.

[298] The damage on a community can lead members to engage in pro-social behaviours[298] which are driven by empathy and desire to support others who have endured a similar traumatizing experience.

Each individual can react differently to traumatic events, and more research needs to be done to learn how to predict vulnerability and access the effects to find solutions that work best.