MANILA - Although a slew of factors could be blamed for the thousands of deaths in the Yolanda disaster area, a study shows that 94% of them could have been been prevented if they were properly warned and evacuated to safer areas.
Based on a draft of the “Assessment of Early Warning Efforts in Leyte for typhoon Haiyan/Yolanda,” the German Aid Agency for International Cooperation (GIZ) said 94% of the casualties in Tacloban, Palo, and Tanauan were caused by the storm surge while 5% died because of high wind speeds.
“Though a spectrum of risk information was available, those in charge of risk management were partly unaware of the dimensions of the hazard and vulnerabilities and/or did not use the information appropriately,” GIZ said.
While state weather bureau PAGASA accurately forecasted Yolanda’s path and strength, it was wanting in terms of warning the public of the storm surges.
“It seems that the PAGASA warnings failed to sufficiently explain and clarify the specific dangers that were coming to the public,” the aid agency said.
It said PAGASA warned of a storm surge relatively late. The first warning came on November 7, a day before Yolanda, of a possible 7-meter high surge.
“Interestingly, two DOST [Department of Science and Technology] institutions, PAGASA and Project Noah, published different expected storm surge heights before the typhoon made landfall… For disaster managers who may check the forecasts from both institutions, the substantial difference in predicted water level heights might be confusing,” the study reads.
Project NOAH’s prediction was much closer to the actual surge of about 2.3 meters to 5 meters.
Only one source of storm surge hazard map was often referred to, that of PAGASA's The map, however, only displayed inundation areas for 1 to 4 meter surges.
“Therefore, it would appear to be reasonable consulting the hazard maps for a similar hazard, the tsunami, where higher wave heights were used as a basis for the inundation area,” GIZ said. It said the Philippine Institute of Volcanology and Seismology (PHIVOLCS) had a tsunami hazard map, but did not particularly display the height of inundation.
These hazard maps are necessary to determine those who need to be evacuated.
“Once a dangerous hazard event is detected by an authorized institution, the persons in the potentially affected areas need to be informed about this so that they can take appropriate action to prevent or reduce damages and losses,” the agency said.
Several local government units (LGUs) claimed to have checked the hazard maps, but many people still died in the designated evacuation centers.
Both hazard maps of PAGASA and PHIVOLCS showed that evacuation centers were within hazard areas.
“It appears that they were not designed to host people seeking protection from storm surges or tsunamis, as most of them were single floor buildings without stilts,” GIZ said.
GIZ said warning communications are also paramount. “Messages have to be clear and unambiguous. Everybody has to understand what danger is coming up and what to do about it.”
GIZ noted, however, that the Office of Civil Defense (OCD) and some LGUs “were apparently not serious enough to make people understand that their lives were in jeopardy.”
Many residents did not know what a storm surge meant, it said. “Accounts of residents suggest that a large part of the population in areas where there were storm surges did not evacuate.”
The agency noted “serious warnings and more effective evacuations along the coastline could have saved many lives.”
GIZ Chief Advisor for Disaster Risk Management Olaf Neussner said the aftermath was a “mix of different things that did not work perfectly well.”
He said proper evacuation could have saved many lives. “You have to delineate carefully the areas that could be affected, evacuations need to be more serious…”
He said the GIZ, which has been involved in disaster risk management in several areas across the country, is now working with the United Nations Development Programme, the UP-National Institute of Geological Sciences (UP-NIGS), among others, to create a new map that would show the inundation or affected areas due to Yolanda.
Asked if the people should have been warned of a tsunami-like surge, Neussner said: “It’s difficult to say if that could have helped. While it’s not to confuse both, people have to learn that they have the same effects.”