Sometime in the early 1990s, I had to make the difficult journey from Kuching to visit the Kenyah village of Long Bulan, deep in the labyrinths of the Rejang Valley, to learn about the impact of the planned Bakun dam.

It was a harrowing trip as our party of 10 had to travel by land through Belaga and cross the Balui River. It took two or three days for us to travel by land, mostly over timber tracks, using a...