Sumatra Megathrust Threat: Bobby Nasution Warns of Aceh Tsunami Tragedy

North Sumatra Governor Bobby Nasution emphasised the importance of megathrust mitigation as an anticipatory measure to protect public safety while maintaining regional stability. According to Bobby, the potential megathrust disaster not only threatens lives but could also have a broad impact on economic activity, public services, social stability, and security aspects. This was conveyed by Bobby while briefing participants of the Domestic Field Study for the Indonesian Armed Forces Command and General Staff College’s LV Regular Education Programme for the 2026 Academic Year at the North Sumatra Governor’s Office on Tuesday (9/6). In his presentation, Bobby explained that a megathrust zone is an area where oceanic and continental plates meet, triggering a subduction process. Such conditions have the potential to generate earthquakes of great magnitude. “Megathrust characteristics include a very large magnitude, occurring in subduction zones, having shallow and wide faults, and the potential to trigger a major tsunami,” said Bobby. He cited the megathrust earthquake that struck Aceh in 2004, triggering a catastrophic tsunami in the Indian Ocean region. According to him, that event serves as a reminder of the importance of preparedness in facing geological disaster threats. Bobby mentioned the Mentawai region and the western coast of Sumatra as areas with megathrust threat potential. Therefore, he reminded the public and all stakeholders not to ignore information or early warnings related to disasters. To mitigate this threat, the North Sumatra Provincial Government is implementing structural, non-structural, and socio-cultural approaches, as well as strengthening interfaith harmony at evacuation sites. The mitigation also prioritises local wisdom based on the values of Nusantara Diversity. In addition, the provincial government continues to undertake various efforts, including strengthening policy and governance, constructing disaster-safe infrastructure, enhancing community preparedness and capacity, reinforcing collaboration and partnerships, and utilising innovation and technology. Bobby also addressed the handling of hydrometeorological disasters that hit several areas in North Sumatra in November 2025. According to him, the impact was managed through collaboration among various parties, including the government, security forces, and the community. Data presented showed the number of people affected reached 1,803,715. Of that number, 11,209 people were displaced, 375 died, five were injured, and 41 were reported missing. As a commitment to accelerating post-disaster recovery, the provincial government has allocated fiscal support through Regional Transfers for rehabilitation and reconstruction for the 2026-2028 period amounting to IDR 23.33 trillion. In addition, there is an additional Regional Transfer allocation for 2026 of IDR 1.134 trillion. Meanwhile, Deputy Commander of the Indonesian Armed Forces Command and General Staff College Teguh Puji Raharjo said the field study for the 2026 Academic Year was attended by 60 participants. The activity aimed to equip future TNI leaders with strategic insights, empirical experience, and the ability to analyse regional defence layout directly in the field. “Also to mitigate threats and disasters. To enhance the students’ ability to detect, analyse, and carry out mitigation against various potential threats,” he concluded.