Earthquake Committee: A Rangoon Quake Would Be ‘Devastating’
By Tin Htet Paing 21 October 2016
The Myanmar Earthquake Committee was founded in 1999 and conducts seismological research on active fault lines and past earthquakes in Burma. Until significant earthquakes hit the country in the last few years, including a 6.8-magnitude quake in Bagan in August this year, the public had not recognized the importance of the committee and its research. Led by seven seismologic academics and researchers, the committee has produced seismic hazard maps for Burma and, most recently, for the populous former capital Rangoon.
Burma’s central areas are prone to seismic activity mainly because of the Sagaing Fault—a 1,200 km (750-mile) fault line that transects the country from north to south, passing through major cities before dipping into the Gulf of Martaban. Aside from Bagan this year, historical records show that nowhere along the line has experienced a major tremor since 1930 when a 7.3-magnitude earthquake hit Pegu (Bago), a city 80 km (50 miles) from Rangoon. The quake claimed more than 500 lives.
According to geological research, a powerful quake tends to strike on the fault line every 80 to 110 years. The Irrawaddy sat down with one of the committee’s three secretaries, U Thura Aung, to talk about Rangoon and the risks it faces from a powerful earth tremor.
Could you tell us what research the committee has conducted over the past years?
The first piece of research we did was the Seismic Zone Map of Myanmar. A draft version was issued in 2003 and the revised version was released in 2005. When the Tsunami hit in 2004, we did field research in the country’s coastal areas. From 2006-07, we have been consistently doing research in both paleoseismology (past earthquakes) and active faults, especially the Sagaing Fault.
Please tell us about research that the committee has done on Rangoon.
After releasing the Probabilistic Seismic Hazard Analysis (PSHA) Map of Myanmar in 2012, we co-conducted a hazard assessment for Rangoon with UN-Habitat and which was finished in 2015. The hazard map was developed based on a four-step methodology of characterizing potential hazards. Unlike our 2012 analysis, we also included both soil density and rock level while investigating the city’s ground during the analysis. We studied how dense the soil of each area is.
The next bit of research we are going to conduct in the near future is a risk assessment of Rangoon. We will especially be assessing buildings in the city. We will conduct a pilot project of at least two townships first and collect data on the strength of the buildings there.
What we are going to do with this research is to create a model that will guide us how to respond when there is a risk. We need to collect a lot of data to prepare this model so it will take at least two years. After, we need to analyze and process this data and create a proper mode appropriate to this country.
Can you tell us about Rangoon’s soil?
Most of the Eastern townships of Rangoon and the ones close to the Hlaing River have soft soil. Geologically, the areas along the river were formed from silt and were built on after many years, that’s why they have soft soil. Some parts of Kyimyindaing Township and downtown townships like Latha and Pabedan also have soft soil. North and South Okkalapa and East Dagon townships were originally farmland and also have soft soil. The distance from the ground level to rock in these areas is also quite large and soft soil areas have a high risk during seismic activity. The area around Shwedagon Pagoda is composed of pretty hard rock. Bahan Township and some parts of Sanchaung and Mingaladon townships have the same situation and will be relatively resistant to seismic waves.
Are Rangoon residents aware of the risks?
This analysis was only finished in December 2015 and is yet to launch, so very few people know about the situation and this research.
If there’s a tremor in Rangoon, what is the most important emergency response?
For an earthquake, the most important emergency response is to create a place where many people can assemble or gather. Individuals need to be aware of how we should protect ourselves. After that, it is essential that people go to a safe temporary shelter or a building which is not very far from their home.
Does Rangoon have such temporary shelters or areas of assembly?
As far as I know, there isn’t such a plan provided for the public to gather when there is a fire, flood or storm in the whole of Rangoon. It is not enough to create a space where a crowd can gather and shelter, the structure has to be earthquake resistant and there should be food and medical supplies.
In many countries, such shelters are not used for disaster purposes only. It can be used in other ways in day-to-day use, for example a church. Sometimes, sports stadiums become makeshift shelters during emergency situations. Most importantly, these buildings should be built to be earthquake resistant. If not, everyone using the shelter will be at risk.
What kinds of buildings are at risk from earthquakes?
Generally, buildings that are not built according to national building codes are at risk. But we can’t judge this by our eyes.
Buildings of wooden frames and bricks [constructed through brick nogging] are the most at risk of collapsing due to earthquake tremors. This type of building is very common. People think the bricks are secured to the wooden frame but actually they are not so they can fall down very easily when an earthquake hits.
If reinforced concrete buildings, in which steel bars are embedded in the concrete, are built according to regulatory standards we can say they are relatively resistant. Wooden houses and bamboo houses have the least possibility to kill people when there is an earthquake.
Different sized apartment buildings also have different resistance to quakes. Tall and thin high-rise buildings have less balance than square-shaped high rises and resistance to strong earthquake waves.
Do you have any advice to Rangoon’s public?
The devastation caused from a quake in Rangoon is unimaginable. With the current urban development and population growth, Rangoon has a high possibility of damage and casualties in the event of an earthquake. It is a result of bad management, a lack of public awareness about disasters, and the fact that many of the buildings have not been engineered to withstand a quake.
I want to alert every individual to always prepare an emergency kit and food in case of an unexpected seismic disaster. Storms can be forecasted; floods give you time to prepare. The only disaster that doesn’t give preparation time is an earthquake. You can’t rely on the government to save you while the earth shakes, because it happens in seconds. You have to prepare for yourself.
Earthquakes can’t be forecasted either naturally or technologically. Things that exist above the ground can be studied but seismic waves happen under the ground. There are limitations to how much we can study about earthquakes—it’s still impossible to forecast an earthquake.