Search This Blog

Thursday, April 14, 2011

The New City - Earthquake Safe - 1

Structural Issues

In his message to the people of Christchurch, as part of the first message from CERA (here), the mayor makes the following statement:

"There are so many challenges, but I am confident that by working together we will succeed with our ultimate goal of building the most earthquake safe city in the world. We have a huge opportunity ahead of us."
Unfortunately there is unlikely to be any formal enquiry into the broad aspects of what happened and why, in the February earthquake, and what is needed for a next time. Without this type of analysis there is no way of having confidence that decisions made now will be sufficient. The current specifications for earthquake-prone buildings, or the construction of new buildings, have become outdated as a result of the February 22nd earthquake. The same is likely to be the case for infrastructure design (roading, water, sewage, power and communications). At present there is nothing to give guidance or direction on what is required to protect against such a violent earthquake.

Equally unfortunate is the high risk that the council will take it upon themselves, with the help of a small group of experts, to design, implement, oversee, and approve what is built. A very useful, and potentially reassuring, act would be for the mayor to expand on what he means by people "working together". This is important because part of the risk is that the wrong groups will become involved as dominating and unaccountable influences, to the exclusion and ultimate detriment of the residents of greater Christchurch, and the future of the city.

Local architects and developers, for example, have decided they should have a leading part in designing the city's buildings (see here and here). How can they do this if the safe-city criteria is not yet known? Why should it be be them? Do they have world leading credentials in designing earthquake safe buildings and cities? Are they world leaders in environmental design, or architectural beauty? Ought we not involve architects from a country like Japan, or a state like California, or perhaps elsewhere? Ultimately professionals must be chosen for their credentials, not because they have nominated themselves.

On the financial side, serious and potentially life and death risks lie in the trade-off between building to a specification and building to a price. Safety requires that a structure be built to meet stringent specifications; failure to meet these must mean that building cannot proceed. Profits require that costs be minimised, and building to a price is simple: as much useful space as can be built should be constructed for as little time and money as possible. There is an irreconcilable conflict between these two objectives: in which direction will the decisions fall?

Council has the role of establishing regulations and other controls to ensure that specifications and standards are suitable, and adhered to. It is, for now, unclear whether the council did a good job of this in the past. Given that there are no guidelines for making the most earthquake safe city in the world, how will designs be assessed and approved? Will the council look at the requirements of residents, which may for instance stipulate a low-rise city? Will there be "business friendly" interim decisions that pre-empt safe-city requirements? Will the council provide a system allowing for applications to deviate from the requirements; if so, will they be notifiable? Will concessions be made to encourage a speedy recovery, or is safety to be paramount?

On all these things we need to be assured that "working together" means the involvement of the residents of greater Christchurch, and the working together process occurs in the open for all to see, before irrevocable decisions are made. Perhaps, very soon, the mayor will satisfy us with an explanation of what constitutes his safe-city, how people will be involved, and what credentials will be required of those who will take a lead in the process.

No comments:

Post a Comment

Note: Only a member of this blog may post a comment.