Sunday, November 13, 2011

Renewing Christchurch & Rethinking Resilience: 3

While it is not the purpose of this report to rewrite the history of Christchurch, it is important to appreciate the role of Christchurch institutions in educating and instilling the reality of earthquake risk in the past. Local institutions that might be entrusted with that responsibility could include: newspapers, the library, the museum, and the council. Schools might also provide locally specific education.

The Christchurch newspaper clipping (Shown here. Newspaper article. The Star newspaper, Issue 7417, 31 May 1902, Page 5. Obtained from “Papers Past”, National Library Archives. Click on it to enlarge it.) provides historic information about a number of things. It describes the fact that the Cathedral spire has been brought down before and “severely shaken” on another occasion. It also describes research:
“from almost all earthquake- ridden countries in the world” and found that “in no earthquakey country is there a spire nearly so high as that in Christchurch”. It also states that “to carry out the work in brick… is quite impossible…”


Newspaper archive research indicates that the top 40 feet of the Cathedral spire were knocked down by earthquake in 1888. The above report relates to the Cheviot centered earthquake in 1901. Reports also record the spire being damaged by earthquake in 1922 and 1929. Apparently there was another significant earthquake just off the coast of Christchurch in Pegasus Bay in 1987 – though it is difficult to track down archive information about this.

However it appears to have triggered research by the New Zealand Earthquake Commission (EQC) at the time (The Earthquake Hazard In Christchurch: a detailed evaluation, by Elder, McCahon and Yetton, 1991), which was largely corroborated by separate research conducted by the New Zealand Institute of Nuclear and Geological Science (NZINGS) which was reported in 1995 (Geology of Christchurch, Brown, R. D. Beetham, B. R. Paterson, and J. H. Weeber, Environmental and Engineering Geoscience, 1995).

This information cites four earthquakes that did severe damage in, and very close to the City of Christchurch (1869, 1901, 1922 and 1987). The NZINGS report (1995) states:
The geology, tectonic setting, and active seismicity of the Christchurch area indicate that future large earthquakes will occur which will have major impact on the city. Earthquakes are expected to produce liquefaction, landsliding, ground cracking, and tsunami. Planning and design to mitigate the consequences of these phenomena are an essential prerequisite for preparedness.... The identification and quantifying of geological hazards, and the implementation of regulation and planning designed to discourage irresponsible land use, should continue in the future as the geological knowledge and database is expanded....
Based on its research the EQC report had predicted a return period for another damaging earthquake in Christchurch of 55 years.

My research into the roles and responsibilities of the Christchurch City Council and the Canterbury Regional Council suggest that their actions have amounted to a conspiracy of silence regarding the risks to buildings and development posed by local seismicity. It has been suggested by many that there was a desire to protect the value of land and not threaten the city’s economic progress.

Estimates of the economic cost of the recent cluster of earthquakes range up $20 billion NZ, with those costs being met by the Earthquake Commission, Central Government, Insurance Companies, Local Government and private pockets. Suffice to note, the earthquake cat is now well and truly out of the bag, which is one reaspon why insurance companies are reluctant to invest in future risk in Christchurch, until the risk is better understood, and until all concerned build and adapt to the conditions. No longer will it be acceptable or appropriate to claim the tallest cathedral when that claim amounts to Don Quixote tilting at windmills. Or the foolish man building his house upon the sand.

(This is a section of my report: Renewing Christchurch & Rethinking Resilience - A Cultural Plan. If you want the whole thing - please contact me.)

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Sunday, November 13, 2011

Renewing Christchurch & Rethinking Resilience: 3

While it is not the purpose of this report to rewrite the history of Christchurch, it is important to appreciate the role of Christchurch institutions in educating and instilling the reality of earthquake risk in the past. Local institutions that might be entrusted with that responsibility could include: newspapers, the library, the museum, and the council. Schools might also provide locally specific education.

The Christchurch newspaper clipping (Shown here. Newspaper article. The Star newspaper, Issue 7417, 31 May 1902, Page 5. Obtained from “Papers Past”, National Library Archives. Click on it to enlarge it.) provides historic information about a number of things. It describes the fact that the Cathedral spire has been brought down before and “severely shaken” on another occasion. It also describes research:
“from almost all earthquake- ridden countries in the world” and found that “in no earthquakey country is there a spire nearly so high as that in Christchurch”. It also states that “to carry out the work in brick… is quite impossible…”


Newspaper archive research indicates that the top 40 feet of the Cathedral spire were knocked down by earthquake in 1888. The above report relates to the Cheviot centered earthquake in 1901. Reports also record the spire being damaged by earthquake in 1922 and 1929. Apparently there was another significant earthquake just off the coast of Christchurch in Pegasus Bay in 1987 – though it is difficult to track down archive information about this.

However it appears to have triggered research by the New Zealand Earthquake Commission (EQC) at the time (The Earthquake Hazard In Christchurch: a detailed evaluation, by Elder, McCahon and Yetton, 1991), which was largely corroborated by separate research conducted by the New Zealand Institute of Nuclear and Geological Science (NZINGS) which was reported in 1995 (Geology of Christchurch, Brown, R. D. Beetham, B. R. Paterson, and J. H. Weeber, Environmental and Engineering Geoscience, 1995).

This information cites four earthquakes that did severe damage in, and very close to the City of Christchurch (1869, 1901, 1922 and 1987). The NZINGS report (1995) states:
The geology, tectonic setting, and active seismicity of the Christchurch area indicate that future large earthquakes will occur which will have major impact on the city. Earthquakes are expected to produce liquefaction, landsliding, ground cracking, and tsunami. Planning and design to mitigate the consequences of these phenomena are an essential prerequisite for preparedness.... The identification and quantifying of geological hazards, and the implementation of regulation and planning designed to discourage irresponsible land use, should continue in the future as the geological knowledge and database is expanded....
Based on its research the EQC report had predicted a return period for another damaging earthquake in Christchurch of 55 years.

My research into the roles and responsibilities of the Christchurch City Council and the Canterbury Regional Council suggest that their actions have amounted to a conspiracy of silence regarding the risks to buildings and development posed by local seismicity. It has been suggested by many that there was a desire to protect the value of land and not threaten the city’s economic progress.

Estimates of the economic cost of the recent cluster of earthquakes range up $20 billion NZ, with those costs being met by the Earthquake Commission, Central Government, Insurance Companies, Local Government and private pockets. Suffice to note, the earthquake cat is now well and truly out of the bag, which is one reaspon why insurance companies are reluctant to invest in future risk in Christchurch, until the risk is better understood, and until all concerned build and adapt to the conditions. No longer will it be acceptable or appropriate to claim the tallest cathedral when that claim amounts to Don Quixote tilting at windmills. Or the foolish man building his house upon the sand.

(This is a section of my report: Renewing Christchurch & Rethinking Resilience - A Cultural Plan. If you want the whole thing - please contact me.)

No comments: