Asia’s wild Salween drops more than five kilometres
The Salween runs about 3,289 kilometres from the Tibetan Plateau to the Andaman Sea, mostly through southwest China and eastern Myanmar, briefly edging Thailand. Extreme elevation and latitude plus isolation make its basin one of Earth’s most ecologically diverse river systems.
The river rises in the Tanggula Mountains of the central Tibetan Plateau near Dengka Peak, its highest source the Jiangmeiergang Galou glacier at 5,432 metres. Headwater streams collect in Cona Lake at 4,594 metres, below which Tibetans call the river Gyalmo Nagqu, black river. With the Lancang and Jinsha it then threads the Three Parallel Rivers World Heritage Site, said to shelter more than a quarter of China’s animal species. The basin, about 283,500 square kilometres, is 48 percent Chinese, 44 percent Burmese and 8 percent Thai.
Flow averages about 68.74 cubic kilometres a year at the China–Myanmar border and roughly 200 along the Thai frontier, reaching an estimated 6,600 cubic metres per second at the mouth. Some 89 percent arrives in the monsoon months from mid-May to November. The delta receives around 180 million tonnes of sediment a year.
About 24 million people live in the basin, some 10 million close to the river, from Tibet at five people per square kilometre to Mon State at 300. Ethnic groups include the Derung, Lisu, Nu, Tibetans and Wa in China, and Akha, Kachin, Karen, Karenni, Pa’O and Shan in Myanmar. For a millennium the river marked frontiers among Burmese kingdoms, Siam and Imperial China, with the Shan States often fought over; British-ruled Burma governed from Mawlamyine for decades, and since 1948 Shan and Karen areas have been contested in Myanmar’s civil war.
It remains one of Asia’s least fragmented big rivers, with only small dams on headwaters and tributaries, although its drop of more than 5,000 metres has drawn Burmese and Thai hydropower planners since the 1970s.
Source: Salween River
