Disasters evacuationEvacuation modeling: finding the best time (and way) to get going
Reports from the Philippines reveal a lack of typhoon preparation and evacuation efforts. When to evacuate — and how – could spell the difference between life and death. Typhoons can cause widespread flooding of surrounding areas, and do not just affect what lies in the path of the storm. Planning an evacuation is a game against nature. Few plans are safe, and the number and complexity of decisions quickly becomes overwhelming — especially as rising water or traffic accidents block roads — but computers can dramatically help emergency services design evacuation plans which people can actually follow.
Reports from the Philippines reveal a lack of typhoon preparation and evacuation efforts.
When to evacuate — and how — spells the difference between life and death. As we know, typhoons can cause widespread flooding of surrounding areas, and don’t just affect what lies in the path of the storm. Planning an evacuation is a game against nature.
Typhoon Haiyan (and similar events around the world) indicate that people do not play this game well … but computers do.
In collaboration with the Los Alamos National Laboratories and the U.S. Department of Homeland Security, our team of researchers at NICTA has developed algorithms to mitigate the impact of natural disasters. They were, for instance, activated to help in power restoration during recent massive Hurricanes Irene and Sandy.
So can we learn from international disasters, and can we apply that information to the Australian context? The answer is a resounding yes to both.
Our team focuses on planning large-scale evacuations for Australian cities. Its goals are twofold:
- to inform policy on what constitutes a good evacuation plan
- to demonstrate that computers are game-changers.
Planning an evacuation is an extremely challenging task, with calculating the best procedure akin to finding a needle in a haystack. There is an astronomic number of possible evacuation plans to consider, even for a small city.
Although few plans are safe, the number and complexity of decisions quickly becomes overwhelming — especially as rising water or traffic accidents block roads — but computers can dramatically help emergency services design evacuation plans which people can actually follow.
To be efficient, computer tools must understand congestion and human behavior. They also need to take into account new information that will become available in real time via river gauges, traffic monitoring or social media.
Ultimately, they can be used to replan part of the evacuation in real time. Let’s look at an example.
An evacuation scenario
The evacuation tools developed at NICTA not only push the frontier of emergency decision support systems — they also show that optimization algorithms have the potential to save lives during disasters.
Consider, for instance, the case of the Hawkesbury Nepean region in NSW. Experts estimate that a flood of the magnitude of the historic event of 1867 will cost A$2.5 billion and affect thousands of residents.
Such an event would see the water reach 19.2m at the Windsor bridge, compared to the normal level of 1.5m.
