Bali bears the brunt of unbridled tourism development

"I'm still in shock. My brother, my father, and my mother were swept away by the waters, and the entire house," located on the riverbank, "disappeared," the 28-year-old woman told AFP, her voice breaking with sobs.

These floods and landslides, triggered by torrential rains, left 18 dead on the "island of the gods" and highlighted the environmental damage caused by years of unbridled urban development and tourism.

The once verdant south of the Indonesian island has been transformed by a tourism boom that has created jobs but weakened land that previously provided water drainage.

By comparing declassified US spy images from the Cold War with recent satellite photos, the start-up TreeMap, through its Nusantara Atlas project, clearly highlights these upheavals.

"All this land is now transformed into roads or buildings, the soil no longer has the same capacity to absorb water," explains David Gaveau, its founder.

More than 4,6 million foreign tourists visited Bali in the first seven months of 2025, more than the 4,4 million permanent residents.

The infrastructure to accommodate them has led to "land conversion and chaotic urban management, accompanied by lax enforcement of land use laws," denounces Made Krisna Dinata, executive director of the local NGO Walhi Bali.

All of this "has put Bali in a very disaster-prone situation," he believes.

Record rainfall

According to data from the local meteorological agency, Bali experienced record rainfall on September 9, particularly in the Badung district, which is home to some of the island's most popular tourist facilities.

"There has never been such heavy rainfall," Bali Governor Wayan Koster told AFP, while acknowledging that infrastructure problems also played a role in the disastrous flooding.

A study of construction along four major rivers will be launched, as well as a hunt for construction that violates zoning regulations, the governor added.

"If the rules are violated, action will be taken to enforce them," he promised.

Regulations to protect Bali's iconic rice terraces from further development are also planned.

But to this challenge is added that of waste management.

According to research conducted in 2019, Bali produces 4.200 tons of waste per day, less than half of which is sent to landfill, explains I Gede Hendrawan, a professor at Udayana University in Bali.

If not properly collected or disposed of, this waste clogs rivers and sewers, worsening flooding, he explained to AFP.

Waste

Balinese authorities are preparing to close a major landfill on the island this year and are urging households to better manage their organic waste.

But a lot of rubbish is likely to end up in the environment, Mr Hendrawan laments, because "we are all faced (...) with the lack of a good waste management system".

Although the local government is working with Jakarta to build a waste-to-energy plant, this is not expected to happen soon, Koster said.

Waste volumes are also likely to increase if the project to open a second international airport in the north of the island goes ahead, aimed at developing, according to the authorities, tourism in this still little-visited part.

Climate change also raises fears of more frequent record rains as a warmer atmosphere retains more moisture.

"If we fail to solve this (waste management) problem, then in December and January, when the rainy season is at its peak, we can fear that an even bigger disaster could occur," warns Mr. Hendrawan.