‘Big One’ scenario in Metro: 52,000 dead, 500,000 injured
MANILA, Philippines – It’s not a question of if, but of when and how.
The scenario following a major tremor hitting Metro Manila is grim—at least 52,000 dead, 500,000 others injured, 500 fires breaking out, 4,000 water supply points cut and nearly 14 percent of the country’s gross domestic product (GDP) wiped out.
The risk of a 7.2 magnitude earthquake striking Metro Manila is as real as the existence of a major fault system, West Valley, that cuts across the burgeoning metropolis from Bulacan province in the north to Laguna province in the south.
According to a preview of a special report by the risk assessment and consultancy firm PSA Philippines Consultancy Inc. (PSA), these other faults add to the risks of the “Big One” striking at the Philippines’ business and commercial nerve center—Philippine Fault Zone, Lubang Fault, Casiguran Fault and Manila Trench.
A summary of the PSA report, “Metro Manila Earthquake Vulnerability Assessment 2019”, said at least two major earthquakes had been recorded originating from the West Valley Fault in the last 1,400 years. There’s been no major movement in the fault since the 16th century, though, said the report, an update of a 2016 report on Metro Manila’s quake vulnerability.
Should the major fault and others resting underneath the metropolis are roused from slumber and cause a 7.2 magnitude earthquake, the projected destruction is of biblical scale, according to the PSA report, citing assessments made by other international agencies.
“Emergency response will be delayed due to the lack of capacity in both manpower and resources and their inability to reach victims,” said PSA, which provides risk assessment services to some of the biggest multinationals with offices in Metro Manila.
“In the initial hours of the aftermath, confusion and delay in the relay of information are expected and may persist for some days,” it said.
“There are also few open spaces in the metropolis to accommodate the influx of short and longer-term evacuees,” PSA added.
The extent of the damage or severity of destruction would depend on two factors—soil composition and quality of building construction, the report said.
The soil composition in Metro Manila is varying but coastal areas, like the northern shore of Laguna Lake and the coast of Manila Bay, “are prone to liquefaction,” it said.
Building quality, or sturdiness, is at best uncertain, the report said, and “noncompliance with national building standards is a major concern.”
“Corruption in regulatory agencies and cost-cutting in construction materials and methods will have compromised the structural integrity of many existing buildings across the region,” it said.
A 7.2 quake, however, was certain to cause unimaginable destruction across Metro Manila. Roads and bridges would collapse, “raising the probability of a regional separation within the metropolis,” according to PSA.
Heavy damage can be expected on lifeline systems, power grids, telecommunications networks and water distribution infrastructure, it said.
“After the initial building collapses, further damage is expected from the breakout of an estimated 500 fires across Metro Manila,” PSA said.
Areas populated by the poor would be hit hard. Fires caused by short circuits and LPG or petroleum tank explosions were likely. “It is estimated that fires could cover as much as 1,710 hectares and result in an additional 18,000 fatalities,” PSA said.
In a 7.2 earthquake scenario, the risk assessment firm said, reservoirs and purification plants were likely to be rendered inoperable, cutting water supply in at least 4,000 locations and causing long-term shortage.
Angat Dam, Metro Manila’s main water source, is highly vulnerable as it straddles the West Valley Fault. “Damage may cause the dam to fail, flooding the Angat River, its tributaries and low lying areas in Metro Manila and Bulacan,” PSA said.
Damage to distribution pipes would unleash contaminants and bring pollution and spread water-borne diseases, it said.
“With limited supplies of potable water, many inhabitants would be exposed to drinking water from unsanitary sources,” said the report. This would multiply the risks of communicable diseases spreading.
The report used Metro Manila’s experience with Typhoon Ondoy in 2009 to get a glimpse of how a post-quake peace and order situation would take shape.
It said two things could happen to millions of Metro Manila residents after the Big One—they would either return to provincial hometowns or, in a worst-case scenario, resort to the looting that would force the national government to declare martial law.
“The reality may fall somewhere in between the two,” PSA said.
The economic impact of the Big One is also catastrophic, the report said. Losses were projected to exceed P2 trillion, nearly two-thirds of the current national budget, and wipe out at least 14 percent of GDP, according to PSA.
Preparation is key, it said. People should purchase and keep in stock food, water, medicines and first aid items to last for at least a week and study “best practices” in reactions prior to, during and after a major quake.
Businesses should also be ready, PSA said. They should be equipped with plans on continuity that identify “external and internal vulnerabilities” and list “back-up solutions.”
Responses and continuity plans “should be simple, tested regularly among employees and updated from time to time.”
While authorities advise people to prepare emergency kits and other supplies good for 72 hours, or three days, PSA said a Big One striking the National Capital Region would require supplies good for at least one week.
Destruction of or severe damage to infrastructure would render many communities inaccessible to relief operations, it said. Transistor radios or satellite phones for those who can afford would be essential readiness tools, PSA said.
Readiness for companies
Companies were advised to prepare business impact assessments ahead of a Big One or any other disaster that could render businesses paralyzed.
“For example, a terrorist attack has low probability but very high impact,” PSA said. “Most routine typhoons have a very high probability but the moderate impact,” it said.
Assessment studies, PSA said, “should consider all possible scenarios.”
Companies would be best served by crisis management teams and the designation of decision-makers. “Quick decision-making is critical during times of crisis,” PSA said.
“Crisis response and business continuity should be tested under realistic conditions,” it said.
Plans, PSA added, “should be living and breathing documents that are constantly updated.”
While no one knows when the Big One would strike, the West Valley Fault is a catastrophe waiting to happen. It struck 700 years apart in the last 1,400 years, according to data gathered by PSA. It’s been more than 500 years now since its last major movement.
PSA, however, said people could heed these tips should the major fault system get up from bed:
Prior to the Big One, people should know quake hazards in homes and offices, determine if homes or buildings are on fault lines and areas prone to liquefaction or landslide; strap or bolt heavy equipment to walls; check stability of hanging objects; store breakable items, chemicals or flammable materials in lowermost shelves; turn off gas tanks when not in use; be familiar with exit routes; know locations of fire extinguishers, first aid kits or alarms and communications equipment; be ready with emergency supply kits and conduct or participate in quake drills.
During a quake, people are advised to stay calm; don’t leave sturdy buildings to go out; duck under sturdy desks; stay away from glass windows, shelves, cabinets and other heavy objects; beware of falling objects; be alert; stay away from trees, power lines, posts and concrete structures; move away from steep slopes; move quickly to higher ground to be safe from tsunamis; do not get off a moving vehicle.
After the Big One, people should prepare for aftershocks; not use elevators; not enter damaged buildings; check for injuries; check water lines and electrical lines; check for chemical spills; leave a message stating location when evacuating homes; get updates through battery-operated transistor radios; find safe exits from weak or weakened buildings or homes; get out calmly; do not drive near disaster-stricken areas; refrain from unnecessary phone calls to relatives or friends.
“Personal safety is of primary concern,” said PSA.