Last week the global landscape of mitigating and managing disasters changed forever. We heard the news of six Italian scientists charged for manslaughter and jailed for six years each for failing to predict the intensity of the 2009 quake that killed over 300 people. They were charged although they had mentioned the difficulty of predicting these extreme events. Some scientists, expressing outrage, said “We won’t advise the state again”.
Sandy struck against the backdrop of these events. Although the wind speeds of Sandy (around 150km/h) were not high as Australian Cyclones Tracy in 1974 and Yasi in 2011, it covered a much wider area. The wind gauge in Tracy was destroyed at 217km/h, although the speeds may have reached closer to 300km/h.
Although the measuring equipment and computer prediction models are much better now, it is not easy to predict the exact path of these devastating cyclones or hurricanes. However a similar or even a less intensive storm could cripple Melbourne, Sydney and other major cities in Australia.
A few years back we did a study funded by the Department of Prime Minister and Cabinet to assess the damage in cities in CBD areas in Melbourne and Sydney due to some extreme events. We identified many vulnerabilities which are difficult to address. Our buildings and infrastructure are not designed for these events, therefore we can expect complete collapse or severe damage. We also found in another study that many of our buildings can go through progressive collapse even under less severe events.
Preparation for these devastating events is not easy. Although buildings can be damaged or even collapse due to large winds, the main problem can come from damage to underground services due to flooding. We saw more than 7 million people affected by power outage in USA. Flooding of road tunnels and damage to storm water and sewage pipes as well as the water supply network could take days or months to recover.
A Queensland resident visiting New York mentioned that she is well prepared because she is used to Queensland cyclones and also she experienced Irene in New York last year. She highlighted the problem many in the southern part of Australia will have. We have not faced major storms and not prepared for them.
Social media may help to improve the communication as we discussed in a forum on New Generation of Disaster Management in Canberra last week. Former Attorney-General and Minister for Emergency Management, Mr Robert McClelland told the forum
While there have been some significant reforms and innovations, and the National Resilience Strategy represents an important change in attitude, there is still a long way to go. Under-resourcing will always be a problem for so long as we concentrate on post event assistance rather than pre-event prevention.
Emergency managers may say, “Don’t stay behind! The best thing you can do to protect yourself and your family is by leaving the area if advised to do so”. There is no doubt this may be the best option, but as we saw in Sandy, these disasters affect a very large area and evacuation is not possible in some instances. As we saw in the bushfires in Victoria, congestion could be a major problem and evacuation strategies sometimes don’t work. For those stuck in a storm, there are measures that can be taken: if you are in high-rise building, take shelter in lower floors as winds become progressively stronger, and don’t use elevators. Fire damage is also a major concern in these devastating events.
Although we have progressed a bit in managing these events, we have still not established proper planning guidelines. For example, in new buildings and other infrastructure designs in Melbourne and generally in Australia we still use the old wind speed and other design guidelines. We do not consider the possible extreme events.
New York didn’t expect a severe storm like Sandy. We can’t rule out the possibility of these catastrophic events in our major cities. Very limited research and development funding is available to come up with innovative methods to prevent loss of life. The extent of damage and how they spread and propagate is difficult to estimate accurately. However if properly supported and funded engineers and scientists, can come up with better predictions of these events and avoid what happened to scientists in Italy. One such study is our current work on flood propagation and effects on infrastructure.
Wade Macdonald
Technician
This is the problem with scientists who claim 'consensus' on such naturally changing issues in which they really know stuff all about.
This planet contols us not the other way around.
alfred venison
records manager (public sector)
the author is an engineer. -a.v.
Richard W
Engineer
While I'm a bit confused about the point of the whole article (is it saying buildings in Melbourne/Sydney should be designed for tropical cyclones? Maybe we should also design for ice loading from Russia? You know, just in case... Strange idea). One that rings alarm bells:
"For example, in new buildings and other infrastructure designs in Melbourne and generally in Australia we still use the old wind speed and other design guidelines"
What does this mean? Everyone I know uses the latest design standards, including the 2011 version of the wind code. This is effectively a legislated requirement. Is the author suggesting that the wind speeds in the recently published Aus Standard are somehow fundamentally wrong? First I've heard of it and I would be really curious to know what other information is available for use.
Wade Macdonald
Technician
Well said Richard,
I wouldn't expect a logical response from the apocalyptic street corner preachers who write some of these articles or frequently post on this forum however.
Dale Bloom
Analyst
I understand many houses in NSW and Victoria have not been built with cyclone bolts, but flooding seems to do most damage.
The heaviest rainfall in New York was only about 15 inches (which is quite common during a Nth QLD wet season), but even a heavy shower of 5 inches of rain now seems to do damage and create chaos in places such as Brisbane and Sydney.
http://www.abc.net.au/news/2012-02-16/major-cities-also-at-risk-of-brisbane-like-flooding/3834688
Priyan Mendis
Professor, Infrastructure Engineering at University of Melbourne
Richard W's comment is very important. The wind code was released in 2011.
Read moreWind codes around the world use old models. They ahve to be reviewed and revised.
I know Australian wind map is under review.
Sorry to be technical, but we use 3 limit states in design 1 serviceability (simply day to day performance) 2. ultimate limit state (failure). 3. Extreme designs (e.g. progressive collapse). These types of extreme storms etc are in category 3. We check for robustness of a structure for that particular…
Les McNamara
Researcher
The failure in Italy was in science communication, and in particular the communication of risk and uncertainty. The scientists weren't convicted because they failed to predict the earthquake or its intensity. Rightly or wrongly, they were convicted because they gave assurances that couldn't be justified given the information and knowledge available to them.
Also, in Italy, the buildings did exactly what engineers expected they would do in an earthquake of that magnitude - fall down. Buildings…
Read moreMeg Thornton
Dilletante
One of the big problems of determining whether or not Australia could weather the impact of a storm like Hurricane Sandy in better or worse condition than the US east coast did is fairly straightforward: we're comparing cherries against watermelon, when it comes to population. The USA has a population of over 300 million people, and a lot of them live on the east coast. Australia has a population of 22 million people total - to put this in perspective, it's around the same amount as the New York…
Read morePeter Hewson
Citizen
The conclusion in this ramble misses the point. Of course future planning may reduce risks but what happens if a cyclone strays south this coming season, will we cope? You mentioned that our cities are much smaller: sure, Sydney has 'only' about four million people but it also has, essentially, only a couple of exits that don't parallel the coast for a fair distance.
It was said that in uptown New York it was as if Sandy was just a bad rain storm. Obviouly the media will report from where the actioned happened but, now, a day later, we are starting to see the damage from New Jersey, still flooded. Perhaps that's the case study to examine.