Sumatra Flash Floods: 41 Dead, Dozens Missing After Volcano Triggers Devastating Mudslide

Heavy rainfall triggered devastating flash floods on Indonesia’s Sumatra Island, resulting in the deaths of at least 41 people, with several others still missing, according to officials. The downpour, combined with a powerful mudslide caused by cold lava from Mount Marapi, led to a river overflowing and wreaking havoc across four districts in West Sumatra province late Saturday night.

More than 100 buildings were inundated, and many individuals were swept away by the raging floodwaters, as reported by Abdul Muhari, spokesperson for the national disaster management agency, on Sunday.

Lahar: Volcanic Mudflows

Cold lava, also known as lahar, is a mixture of volcanic debris and rocks that flows down a volcano’s slopes during heavy rainfall.

Death Toll Rises in Sumatra Floods

As of Monday morning, Ilham Wahab from the West Sumatra disaster mitigation agency confirmed that 41 people had perished, while 17 remained missing. The worst-affected areas included Agam district, where three individuals were unaccounted for, and Tanah Datar, with 14 still missing. These densely populated regions experienced the most severe devastation.

Flash Floods Cut Off Towns in Sumatra

On Sunday, authorities recovered nearly half of the victims in Canduang village, Agam district. Nine bodies were found in Tanah Datar, while eight were discovered in the Padang Pariaman area. The flooding also blocked major roads in Tanah Datar with thick mud, isolating several towns, according to local police chief Kartyana Putra. Footage released by Indonesia’s search and rescue agency, Basarnas, showed roads submerged in murky brown floodwaters.

This disaster follows another tragedy just two months earlier, when torrential rains led to flash floods and landslides in West Sumatra’s Pesisir Selatan and Padang Pariaman districts, killing at least 21 people and leaving five others missing.

Mount Marapi’s Deadly Eruption

Mount Marapi, standing at 2,885 meters (9,465 feet), erupted unexpectedly late last year, claiming the lives of 23 climbers caught in the blast. Since 2011, the volcano has been classified under the third-highest alert level, indicating significant volcanic activity. Authorities advise residents and hikers to stay at least 3 kilometers (approximately 2 miles) away from the summit, as per Indonesia’s center for volcanology and geological disaster mitigation.

Marapi’s Unpredictable Eruptions

Known for its sudden and difficult-to-predict eruptions, Mount Marapi poses a significant threat due to its shallow magma source near the summit. Unlike deep magma movements, which can be detected through seismic activity, Marapi’s eruptions occur without much warning. The volcano has remained active since a January 2023 eruption, which fortunately caused no casualties.

Marapi is among Indonesia’s 120+ active volcanoes. The country’s high susceptibility to volcanic and seismic activity is due to its location along the Pacific “Ring of Fire,” a region known for frequent earthquakes and eruptions.