Best way to prepare for big earthquakes

The deadliest natural calamity is a powerful earthquake. Worse, in some instances, tsunami is also unleashed after a major ground tremor. Earthquakes and tsunamis have taken the lives of thousands of victims in our recorded history due to collapsed structures, landslides, simultaneous fires and mass hysteria.

In the Philippines, we have witnessed the devastation and havoc of the magnitude 7.7 Nueva Ecija killer quake in 1990 when several buildings were heavily damaged, including the Hyatt Hotel in Baguio City. More than 2,000 lives were instantly lost in that catastrophe. Similar traumatic incidents were experienced during the Bohol earthquake in 2013 and the Luzon earthquake of August 1968 which triggered the destruction of the Ruby Tower in Manila that killed 268 of its residents.

The biggest fear that haunt many residents of Metro Manila these days is the dreaded “Big One” because of the tremors that recently happened one after the other in Cebu and Western Visayas, Surigao, La Union and Davao region. This “Big One” refers to the possible movement of the Valley Fault System that runs from Bulacan, the National Capital Region (NCR) to Laguna. The said fault system last moved in 1650 and, according to scientists, it moves every 400-600 years. Hence, we are nearing the lower margin of its movement cycle, though these are just estimates.

According to the comprehensive study done in 2004 by the Philippine Institute of Volcanology and Seismology (Phivolcs), Japan International Cooperation Agency (JICA) and the Metro Manila Development Authority (MMDA), the number of casualties is alarming. Possibly at least 30,000 can perish while more than 160,000 can be seriously injured with a magnitude 7.2 earthquake. Fires will happen and bridges will be destroyed and isolate communities. Millions of houses will be affected, and social unrest will follow. If this happens, the tremor will be felt not only in Metro Manila but also in the provinces of Bulacan, Cavite, Laguna and Batangas.

Level up the preparations for strong earthquakes. To minimize the number of casualties and the damage that earthquakes can cause, we must significantly improve our preparations. First of all, the best are engineering solutions. Drills such as the “duck, cover and hold” are crucial, but they are not enough. And these drills are mere reactions that are being harnessed as muscle memory during and after destructive tremors which usually are magnitude 6.5 or higher.

Our buildings, homes, infrastructure such as bridges must be able to withstand at least a magnitude 8.2 earthquake. This is only possible with the right architectural and engineering designs that must be compliant with the National Building Code of the Philippines. Meaning, qualified professionals must do the job of ensuring that designs strictly follow the required parameters that will safeguard the welfare of residents and travelers. Coupled with these designs is the quality of construction materials such as the steel reinforcements, cement and gravel used. There’s no room for sub-standard materials because of safety issues.

People are vulnerable to the killer weight of debris that would fall on them during the strong shaking that can destroy their roofs and walls. It’s not the movement that kills but the solid materials that are detached mainly because of poor design and inferior quality. Most susceptible are the houses of the informal settlers, which could number in the millions.

We must strictly enforce scientifically determined zonal plans. We have enough data from the Department of Environment and Natural Resources (DENR), Phivolcs, the Department of Science and Technology which can guide us to safety in determining where to build communities. “No build zones” means not to allow houses and other establishments to be constructed on them because of possible landslide, liquefaction and tsunamis. The warning must be taken literally. “No build zones” do not mean otherwise. However, in our country, expediency overrules safety.

The logic here is clear: even if you have the proper design and quality of construction materials, your homes or buildings can still collapse if they are built in hazardous areas. And no amount of drills can save you from a structure that can collapse in a few seconds. Usually, killer quakes last less than a minute. Very seldom do strong tremors last for more than 60 seconds, though this happened in some areas such as in Chile during the magnitude 9.5 killer quake of 1960 where it lasted for more than 10 minutes.

The local government units must not compromise their obligation to fully inspect the construction of homes and buildings in their jurisdictions. They must approve only those construction applications that are going to be safe for their constituents. During construction also, the LGUs must have the capacity to efficiently inspect the compliance of actual works that must be based on the approved plans. And the “no build zones” must be fully respected.

I’ve written several times already about this. I shall always still do so as long as it’s needed because people must be constantly reminded. Same with our officials, both in the national and local governments, they must be pushed to be vigilant with their sworn duty.

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