The end of 2010 and the start of 2011 was a difficult period for the world we knew. As a Brisbane resident, the continuous rains in our state over November and December 2010 presaged difficult times ahead. By January 2011, our Dams were full, the Brisbane River was overflowing its banks and the low-lying streets and parks of our suburb were filling up with brown flood water. On the 10th January, a wall of water swept through Toowoomba and towns at the bottom of the ranges were almost washed away. We felt pretty sorry for ourselves for another month and then a major earthquake struck Christchurch New Zealand on the 22nd February, 2011. This was particularly troubling for us as family and friends lived in or near Christchurch and the television images showed widespread damage to the city. It had been a little over a year since a magnitude 7.1 earthquake had hit the same region in September 2010. But this 2011 earthquake seemed to have specifically targeted Christchuch as the red area in the map of the earthquake zone to the right shows the area where the ground shook most violently
We thought the end of the world was coming in the next month (11th March 2011) when another earthquake and the resulting Tsunami hit the east coast of the Tohoku region in Japan. This undersea earthquake was the fourth most powerful earthquake the world had ever recorded and this time our television screens showed devastation to the towns on this coast only previously considered as parts of Armageddon movies. One of the most worrying aspects of this disaster was the damage done to the Fukushima Nuclear reactor which was in the path of the Tsunami.
What was happening to our planet?
It was a bit over 12 months later in April 2012 we visited Christchurch to attend a family gathering. The day after the celebration we decided to go and look at how the inner city was coping with the widespread damage caused by the earthquake the previous year. Cathedral Square is considered the centre of Christchurch and there was a certain logic that developed among the citizens that the most important building in the city, the Anglican Christchurch Cathedral, symbolized all that had been lost the previous year. It was to a carpark nearby the Cathedral that we drove in 2012 to explore the inner city of Christchurch and check on how it was recovering. The image to the left below is of the Cathedral in the months after the earthquake while the government explored ways of preserving this city icon.
The Cathedral was built over 40 years, starting in 1864. Australians have long called New Zealand the Shaky Isles due to the frequent seismic activity there. This cathedral has been a regular victim of these earthquakes with damage occurring on at least five occasions since 1881. It is New Zealand’s lot to suffer thousands of earthquakes a year, (most of them unnoticed) due to these islands sitting on the margin of colliding tectonic plates. It has been the Cathedral’s spire that has been the most regular feature of Cathedral damage and in 2011 the tower again was again badly damaged. The image to the right below of the cathedral was taken in 2006.
By the time of our stroll around the ruins of the Cathedral in 2012, a hoarding had been put up to protect the site and ensure that the conservation process could continue. As can be seen from the image below, the spire and its supporting tower has gone and the front of the church is supported by metal beams. A lot of work and thinking needed to take place over the ensuing years to determine the future of this amazing and much battered building.
From the Cathedral we then moved on to the rest of the city’s centre to check out how it survived. The answer was “not very well”. A week after the earthquake, the government called a major inquiry into the city’s building standards and the damning report illustrated why by February 2015, 1240 demolitions had occurred within the bounds of the four major avenues of the centre of town. The most devastating example was the Canterbury Television Building which collapsed during the earthquake and caught fire leaving 115 people dead in the ruins. The report mentioned above found the building’s construction faulty and should not have been approved. One of our relative’s husband had visited this building early in the day but had luckily moved on before the quake struck. The image to the left is of this building, a few days after the earthquake.
The damage to the city centre was so extensive that it promoted some innovative actions to enable the shops and cafes of the city to return to providing their pre-earthquake services. Large numbers of shipping containers were brought in to provide temporary structures for commerce to continue. We were very surprised at how effective they were.
The other major cathedral damaged badly by the earthquake was the Cathedral of the Blessed Sacrament, the Catholic Cathedral of Christchurch. We went and visited this devastated building and were quite shocked at how ruined it was. The two bell towers were gone from the front and the dome was destabilized. In the image on the right below, the wall of the cathedral is being held up by stacks of shipping containers. It took seven years to finally make the difficult decision to demolish the cathedral and rebuild. The new Cathedral is expected to be open by 2025.
The damage to the city buildings we examined was consistent with the amazing force that we assumed the earthquake under the nearby hills that neighboured the city had produced. But our guide for the morning showed us other damage to the surrounding suburbs that we had never imagined before in our lives. For example, the damage to a bridge across the Avon River in one of the surrounding suburbs of Christchurch (image to the left) was not produced by force directly applied to the bridge. It buckled due to the force applied by the movement of the upper levels of surrounding ground moving sideways into the river channel, thus buckling the bridge in the process. The image below of a similar broken bridge some years later shows the ruptures in the landscape that produced the movement in the stream’s banks.
Near the bridge over the Avon that we visited, the tell-tale rupture of the earth was visible running away from the bridge and can be seen in the image below left. We were then taken to a friend’s house that had been devastated by the process called liquefaction that caused holes in roads to emerge and swallow cars as well as a curious combination of sand, silt and water to erupt above the ground. This silt can be seen in the image to the right below in the back yard of this friend’s house.
The Otago Council report mentioned above summarises the liquefication process succinctly. “Areas of flat, low lying land with groundwater only a few metres below the surface (Such as the land that Christchurch was built on!), can support buildings and roads, buried pipes, cables and tanks under normal conditions.”
“During the earthquake fine sand, silt and water moves up under pressure through cracks and other weak areas to erupt onto the ground surface. Near rivers the pressure is relieved to the side as the ground moves sideways into the river channels.”
Our visit to Christchurch in 2012 was a confronting experience, not just the witnessing of the earthquake damage to the buildings but the impact on the day to day lives of the citizens of the wider city. So many people lost their houses and were forced to move to areas away from Christchurch where the ground was much more stable than what could be provided in the surrounding suburbs of the city. The broader impact of the earthquake was felt for many years. The photo below, taken while we walked the streets in 2012, summed up the attitude of the locals while they got on with repairing their lives.