Newly Developed Technologies Designed to Assess and Mitigate Geo-Hazard Risks Could Effectively Save Thousands of Lives in Southeast Asia and Beyond
by Imelda V. Abano
I hurriedly ran inside our small hut and took my two little children. We ran as fast as we [could] to get away from the landslide. Tons of soil and rock showered down from the mountain. I heard people screaming for help. When we looked back, our entire village was covered with mud. We [were] all shaking with terror. The next day, I found my husband buried at the foot of the mountain where he was harvesting wood for fuel. It was a nightmare to all of the villagers as one or all of our families were buried alive."
"I was working on our small vegetable farm in our backyard when I felt the earth tremble. I looked up and saw the landslide coming towards me.
Ever since a massive landslide triggered by heavy rains buried an entire village in the Southern Philippines on February 17, 2006, 28 year-old Raquel cannot believe she and her two children survived the terror.
The village of St. Bernard in Leyte, Philippines is among the country's most remote and inaccessible, with poor roads and limited transport and communications links. According to the Philippine National Red Cross, at least 281 houses and an elementary school were swallowed by four meters of mud. According to the Natural Hazards Earth System journal, published in June 2007, 1,100 deaths have been confirmed. Residents of this village, situated at the foot of a mountain, had no warning.
Sitting on the Pacific Ring of Fire
With the Southeast Asian nation sitting on the "Pacific Ring of Fire", the frequency of geological hazards, along with its geographic location, make the Philippines the most vulnerable region in the world for disasters such as landslides and earthquakes that have already killed thousands and caused millions of dollars in damage.
On average, 20 tropical cyclones or typhoons cross Philippine territory every year. Floods and landslides are the common byproducts of not only these tropical cyclones, but the monsoon rains as well.
According to Leoncio Amadore, a Meteorologist from the Philippine Atmospheric Geophysical, Astronomical Services Administration (PAGASA), "the combination of strong typhoons, excessive rain and landslides has caused a great deal of death and destruction in the Philippines." Amadore asserts that climate change is one of the contributing factors in the severity of the typhoons now hitting the Philippines.
Mapping the geohazard areas
According to engineers and geologists from the Philippines and the United States, these tragic disasters can effectively be avoided through newly developed technologies such as a landslide risk assessment system and geo-hazard maps that determine the areas most prone to natural calamities, targeting especially the heavily populated mountainous regions.
To mitigate risk, a new landslide hazard and risk classification scheme has been developed by Artessa Saldivar-Sali, Assistant Professor at the University of the Philippines College of Engineering, and her Masters thesis adviser at the Massachusetts Institute of Technology, Professor Herbert Einstein.
Funded entirely by MIT, Salvidar-Sali explains that the project’s aim is to "mitigate the effects of landslides in mountainous areas and [avoid] any [more] disastrous events in the Philippines."
"We hope that the tool will be made a part of the physical/urban planning process when used by engineers and planners and used to address risks posed by landslides given the rapidly increasing concentration of population and the development of infrastructure and industry in the Philippines and Southeast Asia," Saldivar-Sali explains. She says the new system, while originally designed for mountainous Baguio City in the Northern Philippines, can be applied in any country with similar topography, geology and climate - namely many Southeast Asian countries. The system describes the potential hazard by identifying "hazard contributing factors" - in this case: bedrock geology, slope gradients and vegetation. "This is then followed by characterizing risk through the risk contributory factors, which are population and land use."
The new landslide risk rating system, she explains, could help planners improve building codes, determine zoning and strengthen mitigation measures in mountainous tropical regions frequently hit by typhoons and subsequent heavy rains. This should eventually save thousands of lives. While no governments in Southeast Asia have yet to sponsor the project, Salvadar-Sali says she is willing to help any interested government with its implementation.
Studying the impact of future tsunami through tsunami generator
Aside from landslides and earthquakes, Asian nations to as far as Africa also brace themselves against destructive tsunamis, especially those with sizable populations living near their shorelines.
Dr. Tiziana Rossetto from the University College London (UCL) says her scientist colleagues are now designing an innovative wave generator capable of creating tsunamis in a controlled environment to study their effects on land.
"We hope to gain a better understanding of the way tsunami propagates near coasts and onshore, so that we can predict the sort of forces that the tsunami will cause in buildings and coastlines," Dr. Rossetto explains.
Dr. Rossetto, together with other experts, undertook an immediate survey in Sri Lanka and Thailand after the December 26, 2004 tsunami disaster to research its impact on structures, coastal topography, and the differences in how well-designed versus poorly-designed buildings stood up to the events.
The results of the tsunami experiments using the tsunami generator, according to Dr. Rossetto, will allow for better estimates of likely flooding and damage in coastal settlements if tsunami were to occur. This information can then be incorporated into emergency planning and evacuation strategies for tsunami-prone regions. The experiments will also help inform how to better design buildings likely to withstand tsunami forces.
Dr. Rossetto says that the tsunami generator "will be unique." It will be used to carry out experiments at a scale of 1:100 in a 45m long wave flume, or artificial channel, at the experimental facilities of HR Wallingford in Oxfordshire.
"We will be testing a series of model buildings placed on a beach in the flume and will measure impact forces from tsunami of different sizes. We will also be looking at the effect of having different beach slopes and different types of buildings," she explained. "The tests will also look at erosion of soil around the foundations of these buildings and the implications of this on structural safety."
The project, funded jointly by the Engineering and Physical Sciences Research Council (EPSRC) and HR Wallingford, is scheduled for completion in the summer of 2008.
Life must go on
Now a small vegetable trader, Raquel finds hope in her life through her two children who are now studying in another village in the Southern Philippines. She says she wants to be strong for them in their father’s absence.
"Life has so much to offer. I will not forget the day when my husband died together with hundreds of our villagers. It is hard to be in this situation but I will be strong for the sake of my children," she says.
About the Author
Imelda Visaya-Abaño, began her journalism career in 1998 as a reporter at the Philippine Daily Inquirer, the leading daily newspaper in the Philippines. Her areas of interest are women and children's issues, science, environment, health, agriculture and education.
In 2002, Ms. Abaño was honored as the Asian Winner of the Global REUTERS-IUCN Media Awards on Environmental Reporting.
Ms. Abaño vows to continue serving her community through balanced news and fearless views. She believes in better journalism for better communities.