Jakarta – In the wake of the tragedy in Yogyakarta, in which thousands died in collapsed houses and buildings, experts warned that earthquake-resistant construction standards must be strengthened to prevent future disasters.
"The number of victims in Bantul and Yogyakarta could have been minimized had they built quake-proof houses," said Surono, a geophysicist at the Volcanology and Geological Disaster Mitigation Center.
As of Monday afternoon the government put the death toll from Saturday's temblor at 5,200 in Yogyakarta and neighboring areas in Central Java. About two-thirds of the deaths occurred in the coastal Bantul regency, south of Yogyakarta.
Surono said Monday the proximity of population centers to the quake's epicenter contributed to the high death toll. Yogyakarta is about 37 kilometers from the epicenter, which was 33 kilometers beneath the sea. Quake-resistant construction would at least have given people time to get out of houses and buildings before they collapsed, Surono told The Jakarta Post.
Wayan Sengara, an expert from the Department of Civil Engineering at Bandung Institute of Technology, said most houses in Yogyakarta sustained some structural damage in the earthquake, such as collapsed or cracked walls. But many of the more strongly constructed hotels in the city only suffered light damage, like broken windows.
A government decree issued in the 1970s and revised in 2002 requires local governments to follow quake-proof construction standards, which vary according to the different levels of seismic activity in their respective regions.
"Quake-proof construction increases the cost of a building by about 10 to 15 percent," Wayan said. This extra cost is one reason the standards are often ignored, Wayan said, along with the government's failure to educate the public about the importance of quake-resistant construction. And though there are agencies to supervise building standards, it is thought contractors often get around these standards through bribes.
An expert in structural and earthquake technology at the Public Works Ministry, Suwandojo Siddiq, said pictures of 200 damaged houses in Yogyakarta showed they were all constructed from concrete, while more traditional building materials such as woven bamboo would be harmless in an earthquake.
However, given that concrete is now the preferred building material for houses, he said the best way to make houses quake-resistant was by using steel reinforcements. "People build houses differently in Sumatra, Java and Kalimantan," Suwandojo said, adding quake-proof construction techniques should be adjusted to different areas of the country.
The director of construction at the Public Works Ministry, Antonius Budiono, said officials from the department traveled to the regions each year to monitor construction standards in different areas of the country and inspect buildings. "Buildings should be checked every five years," he said.
Antonius said the Jakarta government had done the best job of enforcing construction standards. In 1996 a magnitude 6.0 earthquake resulted in minimal damage to high-rise buildings in the capital.