The Mekong river runs through China, Laos, Thailand, Vietnam and Cambodia. The higher reaches - in China - have been dammed. This majestic life blood river has not been dammed - so far - in the other countries.
Recently the Mekong River Commission (MRC) proposed the building of a dam at Xayaburi (south of Luang Prabang - World Heritage Site). There are plans for many other dams down the Mekong.
The Mekong is the worlds largest inland fishery, 65 Million South East Asians rely on the Mekong. Damming a river completely changes it's ecosystems and has profound effects downstream of the dam.
Keep an eye on SAVE THE MEKONG, occasionally there is a petition that can be signed.
I have travelled in Laos, Thailand and Cambodia on many occasions - 14 years ago I travelled down the Mekong in Laos on a long tailed boat - an amazing crazy thing - long before the 'gap yah' generation began to trash the place. I have very fond memories of the peaceful serenity in this part of the world.
The shot below was taken in Luang Prabang back then - on film!