The Kayan River ecosystem stretches 570 kilometers, dividing tropical rainforest in North Kalimantan into two parts. One part is protected area as the Kayan Mentarang National Park, the other part fragmented by forest concessions, oil palm plantations, and people’s agriculture lands.
The Kayan River stream plays an important role in the hydrological cycle as well as a sustainable food source for local residents. It supports the livehoods of a number of important species such as slow loris (Nycticebus kayan), the orangutan (Pongo pygmaeus), the sun bear (Helarctos malayanus), and the Borneo Elephant (Elephas maximus borneensis).
Moreover, the Dayak Indigenous people have also inhabited the areas along the river banks for centuries. They depend on the forest for their living and build a unique culture. With history of forest destruction in Kalimantan, the Kayan River ecosystem is the last fortress of Borneo’s tropical rainforest.
Recently, the Kaya River ecosystem has been threatened by the development plan of USD $22.2 billion (Rp 315 trillion) hydropower national project. There are five dams to be built with a total capacity of 9,000 MW, making it the largest hydropower plant in Southeast Asia. This plant is projected to supply electricity needs in the Tanah Kuning-Mangkupadi industrial area. With a mega-project of this size, the Kayan River ecosystem is likely to be threatened.
This hydropower plant will submerge two Dayak traditional villages which are Long Paleban and Long Lejuh. The community will be relocated 10 kilometers downstream. Although there is no comprehensive academic study on the impact of hydropower development on the Kayan River ecosystem, this mega-project plan has been welcomed positively by many parties. The result of the investigative done by Walhi (the Friend of the Earth Indonesia) at the end of 2019 showed that development has begun to run, although it was not clear what the fate of the surrounding communities.