Deforestation's Role in Indonesia's Deadly Floods: Environmental Impact and Urgent Call for Forest Protection

Indonesia's recent catastrophic floods, which claimed hundreds of lives, were primarily triggered by monsoon rains and an unusual tropical storm. However, experts identify another critical factor contributing to the disaster: deforestation.

Environmental specialists, researchers, and Indonesian government officials have highlighted how forest loss significantly exacerbated the flash flooding and landslides that devastated villages with mudflows and left residents stranded on rooftops.

Forests serve vital ecological functions by absorbing rainfall and stabilizing soil through their extensive root systems. When these natural barriers disappear, areas become substantially more vulnerable to sudden flooding and destructive landslides.

Indonesia consistently ranks among global leaders in annual forest loss statistics. Over recent decades, extensive sections of the country's verdant rainforests have been cleared due to mining operations, plantation development, and wildfires.

According to analysis from conservation startup The TreeMap's Nusantara Atlas project, more than 240,000 hectares of primary forest disappeared in 2024 alone, though this represents a decrease from the previous year's figures.

David Gaveau, founder of The TreeMap, explains the critical protective role of forests: "Forests upstream act as a protective barrier, a bit like a sponge. The canopy captures some of the rain before it reaches the ground. The roots also help stabilize the soil. When the forest is cleared upstream, rainwater runs off rapidly into rivers creating flash floods."

Environmental advocates have long urged stronger government protection for Indonesia's forests, which function as crucial carbon sinks by absorbing climate-warming carbon dioxide. These forests also harbor tremendous biodiversity and provide habitat for critically endangered species, including orangutans.

As the disaster's magnitude became apparent, President Prabowo Subianto himself emphasized the urgency of forest conservation: "We must truly prevent deforestation and forest destruction. Protecting our forests is crucial."

The recent floods carried not only collapsed hillsides and mud torrents but also large quantities of timber, fueling speculation about connections between deforestation and the disaster's severity. On a beach in Padang, workers were observed using chainsaws to dismantle massive logs scattered across the sand.

Reports indicate the forestry ministry is investigating allegations of illegal logging in affected regions. Forestry Minister Raja Juli Antoni described the disaster as an opportunity to "evaluate our policies," noting that "the pendulum between the economy and ecology seems to have swung too far towards the economy and needs to be pulled back to the center."

This perspective aligns with long-standing warnings from Indonesia's environmental community. In Batang Toru, one of the worst-affected areas, Uli Arta Siagian from conservation group Walhi reported: "There are seven companies operating along the upstream region. There is a gold mine that has already cleared around 300 hectares of forest cover... the Batang Toru Hydropower Plant has caused the loss of 350 hectares of forest."

Additionally, extensive forest areas have been converted to palm oil plantations. "All of this contributes to increasing our vulnerability," Siagian emphasized.

Sumatra, where flood damage was concentrated, faces particular vulnerability due to its relatively small river basins, according to Kiki Taufik, head of Greenpeace Indonesia's forest campaign. "The massive change in forest cover is the main factor in the occurrence of flash floods," Taufik stated, criticizing the government for "recklessly and carelessly" issuing permits for mining operations and plantations.

Herry Purnomo, country director at the Center for International Forestry Research and World Agroforestry (CIFOR-ICRAF), notes that deforestation rates in Sumatra rank among Indonesia's highest. Forest loss creates additional flooding risks as soil erodes into rivers, elevating riverbeds and diminishing waterways' capacity to absorb sudden heavy rainfall.

According to Herry, who also serves as a professor at IPB University in Bogor, two critical actions are necessary: "Prevent deforestation, avoid it, and also carry out restoration."