Days of torrential rains in Indonesia’s South Sulawesi province killed scores of people and forced thousands to flee their homes.

Local authorities and activists have blamed the degraded condition of the region’s rivers and watershed for amplifying the scale of the disaster.

Upstream mining and forest clearing for farms are believed to have severely silted up the region’s rivers, rendering them prone to spilling over during heavy rains.

MAKASSAR, Indonesia — Days of torrential rain in an eastern Indonesian province last week unleashed flash floods and landslides that killed dozens of people. In the wake of the emergency, local authorities and environmental activists identified land degradation as a result of farming and mining as a key factor intensifying the impact of the disaster.

Heavy downpours were reported across scores of villages across South Sulawesi province between Jan. 22 and 24, including the provincial capital, Makassar. The country’s disaster mitigation agency, or BNPB, reported inundation of up to 2 meters (6 feet) in some areas, with parts of the Trans-Sulawesi Highway cut off. The agency said some of the villages were also hit by landslides.

At least 68 people are confirmed dead as a result of the flooding and landslides, according to BNPB reports as of Jan. 27. Nearly 50 people were injured and more than 3,300 displaced from their homes.

South Sulawesi Governor Nurdin Abdullah said one of the main causes of the flooding was the heavy silting in the Bili-Bili River from upstream deforestation, rendering the river prone to spilling over during heavy rains.

He said the Jeneberang watershed, of which the Bili-Bili is a part, “is in the super-critical category because of the exploitation of forest resources upstream, such as shifting cultivation.”

The sheer volume of rainfall also forced authorities to release water from the Bili-Bili and Lekopaccing dams, exacerbating flooding downstream. The governor said authorities had deployed rescue teams and set up emergency camps, and were distributing food and relief supplies.

South Sulawesi was one of several provinces across Indonesia expected to be hit hard by a more intense than usual rainy season this year. Flooding and landslides are common throughout Indonesia, a vast tropical archipelago prone to natural disasters and torrential downpours, particularly during the monsoon season that typically runs between October and March.

While there’s no question the heavy rains triggered the floods and landslides, the intensity of the disaster was likely due to the degraded state of the region’s watershed and environment in general, activists said.

“Thousands of people have become victims of this ecological disaster, which probably might be the worst that South Sulawesi has ever seen,” said Muhammad Al Amin, executive director of the provincial chapter of the Indonesian Forum for the Environment (Walhi).

Amin said the Jeneberang watershed, spanning 860 square kilometers (332 square miles) and served by seven rivers, had been drastically degraded by mining activities.

“The government and law enforcement seem to ignore these mining activities, which we suspect are operating without permits,” he said.

He said the disaster should serve as a wake-up call for the government to take action on restoring the watershed. He also called on the authorities to review extractive activities throughout the watershed area and close down those operating without permits.

Amin added that development plans, particularly involving coastal land reclamation, must be revised to minimize disruptions to the flow of water downstream to the sea. He also called on the provincial authorities to engage with civil society organizations in reviewing the province’s zoning plans, to identify projects that might lead to further environmental degradation.

“The government must be brave in taking tough actions in the interest of public safety,” Amin said.

Banner image of the flooding last week in Makassar, South Sulawesi province. Image courtesy of the Indonesian National Disaster Mitigation Agency (BNPB).

The story was reported by Mongabay’s Indonesia team and was first published on our Indonesian site on Jan. 26, 2019.

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