Indonesia: Earthquakes and Tsunami – Sunda Straits Tsunami - MDRID013 EPoA update n° 15; (n° 2 for Sunda Straits tsunami operation)

Description of the disaster

Indonesia was hit with several major earthquakes and tsunamis in 2018 when the first major ones struck off Lombok on 29 July 2018 and followed by earthquakes and tsunami in Central Sulawesi on 28 September 2018. Both disasters damaged thousands of buildings and displaced tens of thousands of people.

On 22 December 2018 at 21:27, Indonesia was again hit by a tsunami at Carita Beach in Banten Province and the entire coast around the Sunda Strait, specifically in Pandenglang, South Lampung and Serang districts.

According to Government reports, the event was recorded four times in four different locations with tidal waves reaching a height of 30-90 cm. The highest wave hit Serang sub-district at 21:27 local time with the height of 90 cm. BMKG issued high-tide warning before the tsunami struck for the mentioned area. A tsunami early warning was not issued as the cause of the tsunami was not an earthquake, which the current system monitors and responds to.

The initial prediction on the cause could be that of a possible underwater landslide due to the eruption of Mount Anak Krakatau combined with higher than usual tides due to the full moon. The causes of this event investigated by BMKG (Agency for Meteorology, Climatology, and Geophysics), BNPB (Indonesian Disaster Management Authority) and PVMBG (Centre of Volcanology and Geological Disaster Mitigation) and on 30 December 2018 concluded that the volcanic tremor from Anak Krakatau mountain caused underwater landslide and generated the tsunami wave. The Government has issued a warning to avoid activity along the coastal area.
According to the PVMBG, as of 15 January 2019, there are still eruptions from Mount Anak Krakatau where the authorities have raised the threat level to 3 (out of 5); people are advised to stay clear of 5 km radius from the top of the volcano. The government has announced that the end of the emergency phase in Banten as of 4 January 2019 and the transition phase is set until 3 March 2019; while in Lampung, the emergency phase was extended from 6 to 19 January 2019. As of 25 April 2019, Mount Anak Krakatau threat level lowered to 2 (out of 5); and the safety radius has been narrowed to 2 KM from the top of the volcano.

Based on the official statistics from BNPB on 31 January 2018, the tsunami has caused 437 death, 14,059 injured and 16 are still missing. Displaced people have gone down from 36,923 to 16,198. A total of 1,614 houses are severely damaged, 527 houses partly damaged, and 97 houses lightly damaged. These include 97 hotels and 510 boats severely damaged. According to BNPB, the figures are the final figures of the casualties from the tsunami.

The highway connecting Serang and Pandeglang was cut off by damage and debris from the tsunami and roads to Carita Beach and Matahari Beach were also affected but to a lesser extent.
BPBD together with the military, police, the national search and rescue agency (Basarnas), local government office, Ministry of Social Welfare Volunteers (Tagana), Indonesian Red Cross (PMI), volunteers and the community are provided the initial emergency response to the affected people. As of 15 January 2019, debris clearing, and displacement were still ongoing. The response was coordinated locally from a command post. Heavy equipment is being dispatched to clear debris to ease evacuation and response.