[kebab]

I'm pretty sure the Vietnamese have already began to complain about the impacts of damming in Chinese Tibet.

Though I read that in the news, so take it with a grain of salt

[jhugo]

The Mekong, the usual river that comes up when it comes to water rights, originates in Qinghai province, not Tibet. Any other rivers originating in China and flowing through VN would be even further east.

You might be confused because the Mekong (along with numerous other rivers) originates on the Tibetan Plateau, but that's a geographical feature which is vastly larger than Tibet itself.