BMKG: Tsunami Detection Devices in North Sulawesi-North Maluku Operate Effectively, Delivering Information in Under 3 Minutes

The Indonesian Agency for Meteorology, Climatology, and Geophysics (BMKG) has assured that nine tsunami detection devices installed in North Maluku (Malut) and North Sulawesi (Sulut) are operating well in monitoring the ongoing impacts of the 7.6 magnitude earthquake that struck on Thursday morning.

“The multi-disaster early warning system, or Multi-Hazard Early Warning System, which has been developed over the past four years, has proven to work effectively in this situation,” said BMKG Head Teuku Faisal Fathani during a press conference in Jakarta on Thursday, 2 April 2026.

He assessed that the tsunami early warning system operated in accordance with standard operational procedures since the earthquake occurred, enabling the agency to deliver initial information on the quake and potential tsunami less than three minutes after the event.

Subsequently, the second early warning was issued eight minutes later, before the tsunami alert was finally lifted two hours after the estimated time of arrival (ETA) of the first wave.

Of the nine tide gauges that recorded the tsunami event, six belong to BMKG and the other three to the Geospatial Information Agency (BIG).

“With tsunami wave heights ranging between 0.25 and 0.75 metres, however, in certain locations, the height may increase due to the complex geographical conditions of North Maluku and North Sulawesi, such as the presence of small islands and bays,” stated Teuku Faisal Fathani.

Thus, he continued, the government greatly relies on these existing sensor devices to reduce the significant risks of disaster impacts on the population.

This is in line with BMKG’s monitoring results, which found that the tectonic earthquake occurring at 05:48 WIB with a depth of 33 kilometres is classified as a shallow quake due to uplift fault activity, thus having the potential to trigger a tsunami.

Additionally, BMKG recorded fairly high aftershock activity until 12:00 WIB, with a total of 93 events and magnitudes reaching 5.5 to 6.

Experts at BMKG believe this situation still needs to be vigilantly monitored because the potential for aftershocks is estimated to last one to two weeks, depending on the dynamics of seismic activity in the region.

“Monitoring will continue to be carried out because aftershock activity remains quite high. It is hoped that with good coordination, the impacts on lives and damage can be minimised as much as possible,” he revealed.