The North Sumatra chapter of the Indonesia Environmental Forum (Walhi) has accused extractive companies operating in the Tapanuli region of driving severe environmental destruction that triggered recent disasters across Sumatra.

“We indicate corporate activities as the main cause of the damage, as they are exploitative and have cleared forest cover in Batang Toru,” Walhi North Sumatra Executive Director Rianda Purba said on Friday, November 28, 2025.

Since Tuesday, November 25, 2025 at least eight regencies and cities in North Sumatra have been hit by devastating flash floods and landslides. South Tapanuli and Central Tapanuli have suffered the heaviest impact ‒ tens of thousands of residents have been displaced, thousands of homes destroyed, and large swaths of farmland washed away. In total, the disaster has affected 51 villages across 42 districts, paralyzing local economies and damaging infrastructure, schools, and places of worship.

The worst destruction occurred in areas within the Harangan Tapanuli/Batang Toru ecosystem ‒ across South, Central, and North Tapanuli, as well as Sibolga city Walhi, 66.7 percent of the ecosystem lies in North Tapanuli, 22.6 percent in South Tapanuli, and 10.7 percent in Central Tapanuli.

Stretching along the Bukit Barisan mountain range, this forest acts as the primary water source for surrounding communities, prevents erosion, and supports major watersheds flowing downstream.

Rianda argued that the catastrophe was not caused by extreme rainfall alone. “Every flood carried large logs, and satellite imagery shows deforested areas around the affected sites. This proves human intervention enabled by policies that allow forest clearing,” she said.

Walhi said that the expansion of extractive industries has resulted in deforestation that harms both the environment and local communities. The organization demanded the government:

● Halt all extractive operations in the Batang Toru ecosystem;

● Strictly prosecute environmental offenders;

● Establish integrated protection policies through regional and national spatial planning;

● Guarantee basic needs of disaster survivors;

● Reassess high-risk areas to prevent future tragedies.

“We extend our condolences for the ecological disaster in North Sumatra. We hope survivors receive the support they need,” Rianda said. “We do not want this tragedy repeated. The state must act and punish the violators.”