Gathering outside Thailand's Ministry of Energy Wednesday, they asked the Thai government to hold-off on the project, and warned that it could displace tens of thousands of ethnic residents in Burma, as well as villagers in Thailand.
Similar rallies will be held outside Thai embassies around the world today to protest the project. The 2,800 kilometer Salween River stretches from Tibet in the north, down through Burma and along the Thai-Burmese border to spill out into the Andaman Sea.
Activists warn that the dam project will also threaten the river's ecosystem and endangered wildlife. China is also participating in the project.
Construction of the first of the four dams is scheduled to begin in December. The Hutgyi dam would be built on a portion of the river near the Thai-Burmese border.
Information for this report is provided by AFP.