Tsunami warning buoys fail

Memories of 2004 are still fresh in Sumatra. Source: Wikimedia

All 22 tsunami warning buoys installed near low-lying islands failed to warn the authorities when a powerful earthquake hit near Sumatra on Wednesday, Indonesia has admitted.

National disaster mitigation agency spokesman Sutopo Purwo Nugroho said the buoys were either vandalised or poorly maintained.

“That made it difficult to determine whether or not the earthquake triggered a tsunami,” Sutopo said. A magnitude-7.8 earthquake was registered in Sumatra and on smaller islands, sending thousands of Indonesians fleeing to high ground. It caused little damage.

Indonesian meteorologists issued a tsunami warning but it was lifted after a small tsunami was felt at Padang in west Sumatra.

German and Indonesian scientists installed a system of buoys off Sumatra after the devastating magnitude-9.1 quake killed 230,000 people in 12 countries in 2014.

The system includes sensors on the ocean floor and giant buoys on the water surface that in theory transmit information about earthquake tremors via satellite to observation stations on the coast within 10 minutes of tsunami-strength earthquakes. They cost around US$2.3 million a year to maintain.

“We can easily forget. After the quake in Aceh we wanted to do everything, but by 2015 we don’t have money allocated [to fix the buoys]. Most were broken by vandalism,” said Sutopo Purwo Nugroho, spokesman for the National Disaster Mitigation Agency.

Indonesia, on the fringe of the Pacific “Ring of Fire”, an arc of volcanoes and fault lines circling the Pacific Basin, is prone to seismic activity.

The Sumatran authorities reported that there were not enough evacuation routes or shelters in Padang, home to around one million people.

“There was definitely panic last night, that cannot be denied. But the situation has improved from previous years. People have started to understand how to evacuate safely,” said Zulfiatno, head of the disaster management agency in the coastal city, explaining that shelters could cope with around 200,000 people.

“If we had tried to evacuate outside the city it would have been difficult. Everybody grabbed their bikes and tried to [leave] but it was too much,” said Febridal, a street food vendor in Padang.

The 2004 Boxing Day quake opened a fault line deep beneath the Indian ocean, triggering a wave as high as 17.4 metres.

The province of Aceh in the northwest of Sumatra was close to the epicentre in 2004 and suffered at least 168,000 death.