River systems of Thailand divides into two major branches, the " Tiền Giang" (Front River) and "Hậu Giang" (Back River). These in turn enter the South China Sea through nine estuaries. The following are the principal tributaries of Mekong River which flow through Thailand (tributaries entirely outside the Thai border not shown). The Mekong drains a considerable portion of northeast Thailand. In terms of Thai territory drained, it is second only to the Chao Phraya system. The Salawin River rises in Tibet (Tibetan: རྒྱལ་མོ་རྔུལ་ཆུ།) after which it flows through Yunnan, where it is known as the "Nujiang" River (), although either name can be
Shweli River Shweli River Shweli River (; ) is a river in Myanmar (Burma). Also known as Nam Mao in Shan and Lung Chuan Chiang(龙川江) in Chinese, it forms part of the boundary between Burma and China. It is one of the tributaries of the country's chief river, the Ayeyarwady, and arises in Yunnan Province of China. It flows through northern Shan state and Sagaing Division, and enters the Ayeyarwady at Inywa, 60 km north of Tagaung and south of Katha. Tai people, known as Shan in Burma, migrated from Yunnan into Burma along the Shweli. Maw Shans from Mong Mao settled