Speaker A
On the 4th of September, 2010, an earthquake struck the city of Christchurch in New Zealand in the early hours of the morning. Powerful shaking sent terrified residents running into the streets.
A look at the 2010 and 2011 Christchurch earthquakes, focusing on the deadly February 2011 aftershock, the CTV building collapse, and how the city was reshaped.
Key Takeaways
- Building code compliance and proper engineering qualifications are critical to preventing mass casualties in earthquakes.
- Soil conditions such as liquefaction can be as destructive as the shaking itself in cities built on former wetlands.
- Shallow aftershocks can be more damaging than larger but deeper main quakes.
- Recovery from a major urban disaster can take decades and reshape a city's identity.
What the video covers
- A magnitude 7.1 earthquake struck Christchurch, New Zealand, on 4 September 2010, causing widespread damage but only two deaths.
- Aftershocks continued, and a more violent, shallow aftershock on 22 February 2011 at 12:51pm struck during the busy lunchtime hour.
- Violent horizontal and vertical ground movement caused cars to crash, masonry to fall, power lines and gas mains to fail, and many buildings to collapse.
- Liquefaction occurred because much of the city sits on saturated former wetland, causing soil to behave like liquid and sinking buildings and cars.
- The quake killed 185 people and injured around 6,000, overwhelming emergency services and leaving ordinary residents to help one another.
- The CTV building collapsed, killing 115 of the 185 victims, and a fire later hampered rescue efforts.
- Other losses included the PGC building collapse, an on-site amputation to free a survivor, and a public bus crushed by falling masonry on Colombo Street.
- A Royal Commission found the CTV building did not meet modern standards, had an underqualified designer, and an overseer with a counterfeit degree.
- Council officials had ignored their own concerns about the design during approval, and unusual design features made inspection difficult.
- Rebuilding the city took decades, with damaged buildings removed, historic structures reinforced, and new buildings built to stricter standards.
Full Transcript — Download SRT & Markdown
Speaker A
The power failed. Parts of some buildings collapsed into piles of rubble. For hours, the sound of sirens could be heard across the city as paramedics and police raced to attend to the injured. 1,700 people were hurt. Two died. Many buildings were damaged. It was the worst quake the city had seen in recent history… but it was also just the precursor to something much, much worse.
Speaker A
Christchurch is the largest city in the South Island of New Zealand, with a population of around 400,000. It has a history of earthquakes, with Christchurch Cathedral having been damaged multiple times by quakes in 1881, 1888 and 1901. Quakes continued to affect the city throughout the 1900s, though most of these caused only moderate damage within Christchurch. The city was not considered to be among the highest risk of deadly earthquakes. Nonetheless, buildings within the city were designed to meet strict building codes that were frequently updated over the years.
Speaker A
On the 4th of September, 2010, a 7.1 magnitude earthquake originating 40 kilometres (or 25 miles) west of Christchurch shook the city. Taking place, as it did, at 4:35am, the shaking woke many residents from sleep, and sent them running out into the street. It interrupted the power supply to most of the metro area, and caused water and gas lines to rupture. Significant structural damage was seen throughout Christchurch, but no major occupied buildings completely fell.
Speaker A
Two people were killed during this earthquake: one by a fall from height, and one by a heart attack precipitated by the stress of the situation.
Speaker A
Over the weeks that followed, fallen masonry was cleared from the city's streets, the injured were treated in hospital, and normal life resumed. Or, almost normal life: Christchurch was now occasionally shaken by aftershocks of the September 2010 quake. For the most part these caused only minor structural damage, disruption, and power outages.
Speaker A
On the 22nd of February, 2011, however, an aftershock took place that was significantly more violent than any other the city had seen. Although this aftershock was less powerful than the original 2010 quake, it also originated at a much shallower depth, and thus caused ground movement that was far more violent. It struck at 12:51pm. Lunchtime, when the vast majority of people in the city's Central Business District were awake and active.
Speaker A
The streets were crowded. Public transit was full. The city's roads were busy with traffic.
Speaker A
As the quake took place, the ground shook both horizontally and vertically. Cars veered off the road. Masonry crumbled and fell, sometimes smashing into people or vehicles on the ground below. Pedestrians stumbled as they tried to move away from danger. Power lines fell. Gas mains ruptured. And many, many buildings suffered severe damage, or even total collapse. Further to this, there was significant liquefaction.
Speaker A
Large parts of Christchurch are built on land that was once swampy wetland. The ground contains layers of sand, silt and very fine gravel, all saturated with water. When there is no ground movement, these layers are stable… but during a quake or other violent geological event, the solid particles are destabilised and the previously solid soil begins to behave like a liquid. During the Christchurch quake, a huge flood of silt welled up through the ground, flooding large areas and then solidifying again once the shaking stopped. The end result was that buildings, cars and trees sunk into the ground itself, or were submerged beneath layers of silty mud.
Speaker A
After less than a minute of intense shaking, Christchurch was devastated. There were deaths and injuries across the city, with more than 6,000 people hurt.
Speaker A
The sheer scale meant that emergency services were instantly overwhelmed. There were casualties everywhere… and trained personnel could not be everywhere at once. In many cases, ordinary people were left on their own, to help themselves and each other as best they could for at least the first few hours after the quake. People provided first aid to one another. They shared news and resources, and comforted one another through almost continuous minor aftershocks. For the most part they did so outside, in the street, as they were unsure which buildings were safe to occupy. Many structures in Christchurch had been all but levelled by the quake. The tower and spire of Christchurch Cathedral fell, and many of the well-preserved brick-and-mortar historical buildings in the city centre completely crumbled. The quake completely changed the shape of the city in moments.
Speaker A
Local councilman Barry Corbett later said, "When the shaking had stopped, I looked out of the window, which gives a great view onto Christchurch, and there was just dust. It was evident straight away that a lot of buildings had gone."
Speaker A
It wasn't just historical buildings, either. Some newer, high-occupancy buildings had fallen during the quake. One of the most prominent was the CTV building.
Speaker A
This seven-storey mixed-use office building was named for its biggest tenant, Canterbury Television… but it also housed many other businesses, including a school, a clinic, and a relationship counselling service. Almost the entire building collapsed into rubble during the quake, leaving only a lift shaft and a partial wall still standing. Those inside would have had only seconds to act, from the start of the shaking to being buried beneath tonnes of steel and concrete. Very few people who were inside the CTV building when the quake began made it outside before the collapse. Some occupants of the building were left pinned in the rubble, alive but trapped. At least eight students of the language school attempted to make cell phone calls from within the rubble in the minutes and hours after the collapse.
Speaker A
Emergency services concentrated their efforts around the CTV building… but were soon driven back by a fire that tore through the wreckage. It took several days to completely extinguish the flames, and by the time they were out there were no more survivors to be found. Those who might have survived the collapse had been killed by smoke, flames, or by an accumulation of the water used by firefighters to control the blaze. Elsewhere, the five-storey Pyne Gould Corporation (or PGC) building had collapsed, trapping dozens of people. Emergency workers were forced to perform at least one on-site amputation to free a survivor. On the city centre Colombo Street, falling masonry had crushed a public bus, resulting in the deaths of all but one person on board. In total, the quake killed 185 people, and injured 6,000, many of them severely. It was an unprecedented loss of life, and it was accompanied by devastating levels of structural damage across the city. It was clear from the start that the rebuilding of Christchurch would take not just years, but decades.
Speaker A
Of the 185 people who died, 115 had been in the CTV building when the quake struck.
Speaker A
A Royal Commission of Inquiry sought to determine why the CTV building had fallen, and why the death toll had been so high. It was found that, in common with many buildings in Christchurch, the CTV building was not compliant with modern building standards, which had changed dramatically over the decades since it was built in 1987. Further to this, in the particular case of the CTV building, it was found that the engineer who had designed the building was not adequately qualified to do so, and the engineer who had overseen the construction had been in possession of a counterfeit degree.
Speaker A
City officials had been pressured into ignoring their own reservations about the design of the building when it was first proposed… and once it had been constructed, unusual elements in its design made it difficult to correctly inspect. No crimi
Speaker A
for at least the first few hours after the quake. People provided first aid to one another. They shared news and resources, and comforted one another through almost continuous minor aftershocks. For the most part they did so outside, in the street – as they were unsure which buildings were safe to occupy. Many structures
Speaker A
in Christchurch had been all but levelled by the quake. The tower and spire of Christchurch Cathedral fell, and many of the well-preserved brick-and-mortar historical buildings in the city centre completely crumbled. The quake completely changed the shape of the city in moments.
Speaker A
Local councilman Barry Corbett later said, “When the shaking had stopped I looked out of the window, which gives a great view onto Christchurch, and there was just dust. It was evident straight away that a lot of buildings had gone.”
Speaker A
It wasn’t just historical buildings, either – some newer, high-occupancy buildings had fallen during the quake. One of the most prominent was the CTV building.
Speaker A
This seven-storey mixed-use office building was named for its biggest tenant, Canterbury Television… but it also housed many other businesses, including a school, a clinic, and a relationship counselling service. Almost the entire building collapsed into rubble during the quake, leaving only a lift shaft and a partial wall still standing. Those
Speaker A
inside would have had only seconds to act, from the start of the shaking to being buried beneath tonner of steel and concrete. Very few people who were inside the CTV building when the quake began made it outside before the collapse. Some occupants of the building were left pinned in
Speaker A
the rubble, alive but trapped. At least eight students of the language school attempted to make cell phone calls from within the rubble in the minutes and hours after the collapse.
Speaker A
Emergency services concentrated their efforts around the CTV building… but were soon driven back by a fire that tore through the wreckage. It took several days to completely extinguish the flames, and by the time they were out there were no more survivors to be found. Those who might have
Speaker A
survived the collapse had been killed by smoke, flames, or by an accumulation of the water used by firefighters to control the blaze. Elsewhere, the five-storey Pyne Gould Corporation (or PGC) building had collapsed, trapping dozens of people. Emergency workers
Speaker A
were forced to perform at least one on-site amputation to free a survivor. On the city centre Colombo Street, falling masonry had crushed a public bus, resulting in the deaths of all but one person on board. In total, the quake killed 185 people,
Speaker A
and injured 6,000 – many of them severely. It was an unprecedented loss of life, and it was accompanied by devastating levels of structural damage across the city. It was clear from the start that the rebuilding of Christchurch would take not just years, but decades.
Speaker A
Of the 185 people who died, 115 had been in the CTV building when the quake struck.
Speaker A
A Royal Commission of Inquiry sought to determine why the CTV building had fallen, and why the death toll had been so high. It was found that, in common with many buildings in Christchurch, the CTV building was not compliant with modern building standards,
Speaker A
which had changed dramatically over the decades since it was built in 1987. Further to this, in the particular case of the CTV building, it was found that the engineer who had designed the building was not adequately qualified to do so,
Speaker A
and the engineer who had overseen the construction had been in possession of a counterfeit degree.
Speaker A
City officials had been pressured into ignoring their own reservations about the design of the building when it was first proposed… and once it had been constructed unusual elements in its design made it difficult to correctly inspect. No criminal charges were pursued against the
Speaker A
unqualified engineers who had been involved in the design of the CTV building. The remnants of the structure were gradually cleared from the site, and a garden of remembrance was established in its place. Similarly the PGC building has also been cleared,
Speaker A
and a public park established on the ground it once occupied. In the years that followed, thousands of damaged buildings were removed from Christchurch city centre, and the entire skyline of the city was reshaped. Old buildings underwent extensive reinforcement and stabilisation, and new buildings were constructed to meet and even exceed standards
Speaker A
for earthquake-resistance. Reconstruction work is still ongoing, and will be for years to come. Earthquakes, of course, cannot be prevented. Cities, however, can be built to withstand them as much as possible. Christchurch in New Zealand is still in the process of rebuilding
Speaker A
itself after the devastating earthquake of 2011. Lessons learned in the aftermath mean that, as it is rebuilt, it will be rebuilt stronger and safer than it was before.
Topics:Christchurch earthquake2011 earthquakeCTV building collapseliquefactionNew ZealandRoyal Commissionbuilding codesearthquake disasterurban rebuildingseismic safety
