BMKG Warns of Potential Tsunami Risk in Balikpapan Bay  

Balikpapan: The Meteorology, Climatology, and Geophysics Agency (BMKG) has warned of potential tsunami risks along the East Kalimantan coast and Balikpapan Bay. Experts have stressed the need for continued monitoring, especially in coastal areas.
 
“The East Kalimantan coastal area, encompassing North Kalimantan, East Kalimantan, and South Kalimantan, is vulnerable to tsunamis generated by earthquakes originating from outside the region," said Rasmid, Head of the Balikpapan BMKG Geophysics Station, in a statement on Sunday, June 21, 2026.
 
Tectonic activity in the North Sulawesi subduction zone, the Maluku double subduction zone, and the Philippine subduction zone, as well as underwater landslides along the Sulawesi fault line, may trigger devastating tsunamis capable of reaching the East Kalimantan coast.
 
Rasmid expanded, stating “This phenomenon has occurred during several major earthquakes in Indonesia, when large amounts of seabed material shifted and generated tsunami waves.”
 
He explained that the seabed topography in the Sulawesi Sea and Makassar Strait has a steep slope. When earthquakes occur in the region, underwater slopes may collapse, triggering large landslides that displace significant volumes of seawater.
 
Although the waves are expected to be relatively low upon reaching the East Kalimantan coast, they may intensify when entering through narrow bays – such as the Balikpapan Bay – due to wave reflection and amplification caused by the superposition effect.
 
“These characteristics of Balikpapan Bay are an important factor in tsunami risk assessments in East Kalimantan,” Rasmid explained.
 
Amid recent natural disasters, the BMKG has highlighted the need to strengthen disaster mitigation systems. At present, Balikpapan and most areas within Kalimantan lack an integrated tsunami early warning system (EWS).
 
Warning information from the BMKG is still transmitted through coordination channels to the Regional Disaster Management Agency (BPBD) and local governments, before being relayed to the public. An EWS would ensure faster and more effective communication between the BMKG and local communities.
 
“With increasing development and growth in the East Kalimantan coastal areas, disaster education and strengthened mitigation systems are key to minimizing the risk of disasters, should they occur at any given time,” he concluded.
 
(Jonathan Sianto)