Effective restoration can avoid peatland fires: Large scale counterfactual assessment in Kalimantan, Indonesia.

Peatland fires are the third largest source of greenhouse gas (GHG) emissions in Indonesia, a country that stores over half of the world's tropical peatland carbon. These fires cause significant economic losses to human health, crops, and forests. After the devastating 2015 fires, the Government of Indonesia and several partners initiated large scale restoration efforts via peat rewetting with canal blocks. We report on a statistical counterfactual evaluation of peat rewetting on fire occurrence in peatlands in West and Central Kalimantan from 2017 to 2022. We find heterogeneous impacts of rewetting: canal blocks with overlapping rewetted areas were the most effective for avoiding fires. If all canal blocks were effective, rewetting could avoid up to 6.4% of the burnt area, reduce 0.4 MtCO2e emissions, and deliver economic returns of more than a 100% in 10 years in the best performing locations.