In 2015, Indonesia's devastating El Niño fires burned 2.6 million hectares and sent toxic haze across Southeast Asia. 11 years later, restoration efforts had helped cut burned peatland area by 70% in 2023 compared with 2019, showing the value of rewetting

Indonesia's peatlands are among the country's most fire-prone and environmentally important landscapes. When these ecosystems are damaged and dried out, they can become highly vulnerable to wildfire. The danger increases during El Niño, when prolonged durations of reduced rainfall can leave peatlands dangerously dry.

The consequences can extend well beyond the areas where fires begin. Large peat and land fires can damage habitats, threaten wildlife, affect communities and send smoke and pollution in Southeast Asia.

Recent El Niño years have repeatedly been connected with major fires in Indonesia. Severe fire seasons occurred in 2015, 2019 and 2023, while another strong El Niño developing in 2026 has raised concerns regarding renewed wildfire activity.


Indonesia's experience, however, also provides proof that restoring degraded peatlands can reduce fire risk. Rewetting damaged peatlands has helped lower wildfire activity in restored areas, although researchers warn that restoration alone cannot substitute for safeguarding peatlands that remain intact.

The disaster that changed Indonesia's approach

The devastating fire season of 2015 followed a major El Niño-related drought. Around 2.6 million hectares of land burned that year, equivalent to about 6.4 million acres.

The fires continued for months, producing pollution and emissions that affected millions of people in Southeast Asia. Economic losses were estimated at over US$16.1 billion (£9 billion), while the environmental and health consequences added substantially to the damage.

Drought was a significant factor, but it was not the only reason the fires became so severe. Peat ecosystems had already been altered by deforestation, canal construction and drainage associated with agriculture and other forms of development.

When peatlands are naturally wet, their high moisture content makes them much less susceptible to burning. Draining them changes that condition, leaving the organic-rich peat more exposed to fire during prolonged dry periods.

The scale of the 2015 disaster prompted Indonesia to establish a national restoration program.

A national restoration program

In 2016, the Indonesian government established the Peatland Restoration Agency with the goal of restoring damaged ecosystems and helping prevent future fires.

The restoration effort later expanded. By 2020, it also included mangrove restoration, intended in part to strengthen the climate resilience of Indonesia's coastlines.

Wildfire hotspot numbers declined across Indonesia after the restoration program was introduced. However, researchers had not earlier established how much of that decline could be linked directly to peatland restoration.

As per Resti Salmayenti, Dominick Spracklen and Joseph Holden, The Conversation examined that question by comparing restored peatland with similar unrestored areas in Sumatra and Kalimantan.

Their study discovered that large-scale restoration reduced wildfire hotspots by up to 22% in restored areas during the 2019 El Niño. The number of peatland fires was 38% lower than in 2015.

By 2024, the restoration program had covered around 1.6 million hectares of peatland, or almost 4 million acres.

The broader results also point to the value of continued restoration. By 2023, burned peatland area had fallen by 70% compared with 2019, highlighting the potential benefits of rewetting degraded landscapes.

How rewetting reduces fire risk

The research analyzed two main approaches to restoring peatland moisture: canal blocking and deep wells.

Deep wells provide water to peatlands that become dry during the dry season. Pumps can draw water from the wells and release it onto surrounding areas. The approach can both rewet dry peat and provide water that can be used to help extinguish fires.

Canal blocking takes a varied approach. Instead of pumping water, barriers are placed in drainage canals to slow or stop water from flowing away. By retaining water, the blocks can help keep nearby peatland wet.

The researchers found that restoration reduced fire hotspots by up to 22% between 2015 and 2019 across nearly 4,000 square kilometers of peatland where rewetting had been effective.

Deep wells performed better overall in minimizing fire risk. Pumped water can directly reach dry peat, cover a wider area and be used during firefighting. The infrastructure also lasts longer, according to the research.

Canal blocking has limitations because its effect is generally concentrated within a few hundred meters of each structure. But that does not mean canal blocking is ineffective.

Under suitable conditions, it can outperform deep wells when restoration teams select appropriate locations and block enough canals, particularly when the structures are installed in clusters.

Another difficult fire season ahead

The current strong El Niño is expected to peak later in 2026 and bring reduced rainfall. Hundreds of wildfire hotspots have already appeared, including across peatland areas.

Between January and June 2026, the Indonesian government recorded over 100,000 hectares of burned land, or about 247,000 acres.

The figures underline the continuing vulnerability of Indonesia's landscapes despite the progress made since 2015.

The restoration program itself is also facing uncertainty. By 2024, around 1.6 million hectares of peatland had been restored, but the agency responsible for the restoration effort saw its mandate end that year. Responsibility was subsequently transferred to multiple ministries.

That change has raised questions regarding the continuity of Indonesia's peatland restoration efforts at a time when the risk from drought and wildfire remains significant.

Protecting intact peatlands remains the priority

Restoring degraded peatlands can make a measurable difference, but it cannot replace the protection of peatlands that remain intact.

Pristine peat forests have not been subjected to the same drainage, logging and other forms of ecosystem damage that increase fire vulnerability. Preventing that degradation in the first place is therefore crucial.

Indonesia's experience since the catastrophic 2015 fires shows that restoration can reduce wildfire risk when peatlands are successfully rewetted. At the same time, the continuing vulnerability of restored areas demonstrates why maintenance, continued investment and protection of intact ecosystems are all necessary.

The findings offer a clear lesson as another El Niño develops: reducing wildfire risk is not only about fighting fires once they begin. It also means keeping peatlands wet, repairing restoration infrastructure and preventing healthy peat ecosystems from being degraded in the first place.

Source: PHYS.ORG

FAQs:

Q1. Why are peatlands vulnerable to wildfires?

Peatlands can become highly flammable when they are drained and dried out. Prolonged drought during El Niño can increase this vulnerability.

Q2. What is El Niño?

El Niño is a periodic warming phenomenon that can influence weather patterns around the world. In Indonesia, it can contribute to prolonged periods of reduced rainfall.