Why is Indonesia shifting its capital, explained?

A law to move Indonesia's capital from Jakarta to Nusantara, a new city to be constructed on the island of Borneo, was adopted by the Indonesian Parliament on January 18. The choice was made in response to mounting worries about Jakarta's long-term viability. However, as the mammoth project now begins, the relocation to Borneo's wooded East Kalimantan region has brought up its own worries about the area's environmental impact.