Hot mudflows destroy rubber and rice crops in North Sumatra, sparking fears of another Lapindo disaster, Indonesia

Hot mudflows struck the Roburan Dolok village, South Panyabungan District, Mandailing Natal Regency on April 25, with the National Disaster Management Agency (BNPB) confirming 15 eruptions spread across five locations on April 30.

According to the BNPB, the eruptions have destroyed or damaged about 5 ha (12 acres) of rubber plantations. Meanwhile, some local reports indicate that the damage has extended to a much greater area, affecting rice crops as well, and leaving some lands infertile.

According to the locals, the village is no stranger to hot mudflows, but their frequency has been increasing since 2018, and it has intensified in the last few months.

The mud has contaminated the water supply of 4 villages, while the gas emissions consisting of sulfur have polluted Roburan Dolok. The BNPB assured the residents that, though the emissions consist of sulfur, they are free from its toxic form, Hydrogen Sulfide (H₂S).

Teams from the Ministry of Energy and Mineral Resources have collected samples for the analysis of the constituents of the mud flow’s sludge.

Rianda Purba, Executive Director of the North Sumatra office of the Indonesian Forum for the Environment (Walhi), reported that 21 active eruptions have been identified in Roburan Dolok village so far.

“Most of these mudflow eruptions are located just 10 to 15 m (32 to 50 feet) from a drilling site operated by PT Sorik Marapi Geothermal Power (SMGP),” he said on Monday.

“The company claims they drilled the site in 2017 but halted their activities because of a lack of geothermal resources. It is suspected that the spreading mudflow is linked to the company’s operations,” Rianda added.

He noted that PT SMGP has been linked to several disasters in the region since the company began operations in 2017.

In February 2024, residents of Sibanggor Julu and Sibanggor Tonga —located about 9 km (5.5 miles) from Roburan Dolok Village— fell ill, vomited and lost consciousness shortly after SMGP began operating a recently drilled geothermal well about 700 meters away.

At least 123 people were hospitalized for suspected toxic gas poisoning, while around 300 others were evacuated. Similar incidents occurred in 2022 and 2021, affecting dozens of people and resulting in five fatalities.

Walhi’s Rianda Purba has urged the government to take immediate action, warning that local residents are terrified of a repeat of the devastating Lapindo mud volcano disaster.

The Lapindo mudflow—also known as the Sidoarjo mudflow or Lusi (short for Lumpur Sidoarjo)—is a mud volcano located in the Porong subdistrict of Sidoarjo, East Java. It began erupting on May 29, 2006, and has since become the largest mud volcano in the world.

Within days, the mudflow had inundated an area twice the size of Central Park, submerging roads, factories, and homes. The disaster resulted in 20 fatalities, displaced nearly 40 000 people, and caused damages exceeding USD 2.7 billion.

The mudflow continues to erupt to this day.

PT SMGP has denied any link between their operations and the mudflow eruptions in Roburan Dolok village, claiming that the incidents are a natural phenomenon that has been occurring in the area for the past four years.

References:

¹ Hot mudflow erupts in village in Indonesia’s North Sumatra, reviving fears of another Lapindo disaster – ANN – April 30, 2025