SALWEEN RIVER BASIN
The names of the Salween
In Myanmar, the Burmese refer to the Salween as the Thanlwin, while in Mandarin it is referred to as the angry river, the Nu Jiang. In Thailand, it is referred to as the Salawin.
The Salween rises on the Tibetan Plateau, and then flows for about 2,400 km to its mouth on the Gulf of Martaban. As it descends through China, the Salween passes through a UNESCO World Heritage Site known as the Three Parallel Rivers, alongside the Mekong and Yangtze rivers. From its source to the China-Myanmar border, the river drops 4 KM in altitude.
Over 10 million people live in the basin – 3.8 million in China, 6.1 million in Myanmar, and about 600,000 million in Thailand.
The Salween’s waters
It is not known precisely how much water the Salween issues into the sea, and estimates range from an average of 94 to 263 KM³ a year. On the Tibetan Plateau, 8% water is estimated to come from glacial meltwater, 28% from snowmelt, 22% from base flow (water from the ground that seeps slowly into the river channel over time) and 42% from rainfall (with seasonal variations). The river’s long and narrow basin covers over 283,000 KM².
The people of the Salween
Over 10 million people live in the basin – 3.8 million in China, 6.1 million in Myanmar, and about 600,000 million in Thailand. Population density is highest in Mon State (more than 300 people per KM²) and western Yunnan (up to 100 persons per KM²), and lowest in Tibet (5 people per KM²). There is great ethnic diversity in the basin. Amongst academics, the huge highland ethnic diversity in the Greater Mekong is sometimes gathered under a fictional region or country named ‘Zomia’. Note in penultimate paragraph “The Salween stretches across 17o of latitude
Fishing on the Salween
Little is known about the fish species diversity in the Salween; or about how much fish is landed annually. Nevertheless, livelihoods studies show that fishing is very important to people living alongside the river and its tributaries.
Curious Salween shapes
On the Nam Pang, a tributary of the Salween in Myanmar, a series of curious ‘weirs’ cross the river both to the north and south of Kunhing in Shan State. These can be seen on Google Earth, and are an unusual feature known as ‘travertine barrages’ or ‘tufa’. These are formed from soluble minerals in the water that form through precipitation.
A conservation river?
The mainstream of the Salween is one of the last free flowing rivers in the world. For the time being, China has cancelled its hydropower development ambitions for that part of the river in China. Much of its basin in Thailand lies in a protected area.
And in Myanmar, massive planned dams are mired in controversy. Nevertheless, there are dams in the basin. In China, there are 23 hydropower dams of 15 MW installed capacity and above, and 10 irrigation dams with a reservoir surface area of 0.5 KM2 and above. In Myanmar, there are 4 hydropower dams and 6 irrigation dams. Thailand has yet to construct any dams in its part of the basin.
The Salween stretches across 17o of latitude, and 5,500 metres of altitude and therefore displays a wide array of different ecological habitats ranging from tropical monsoonal to tundra, and five major ecoregions. The Three Parallel Rivers UNESCO World Heritage Site, which supports over 25% of the world’s and 50% of China’s animal species, with 77 species of animals, 34 species of native plants and four fish species listed as protected or endangered. The river supports the world’s greatest diversity of turtles, and the wetlands of the Salween’s Delta support populations of the fishing cat. Myanmar’s second largest lake, Inle, is to be found in the Salween Basin. Lake Inlay became a UNESCO Biosphere Reserve in 2015.
While water quality is generally good, many economic activities threaten this status. Illegal logging, a source of income for both government and ethnic armed groups, has seriously degraded forests in the past 20 years.
Salween River Basin map
Click below to download the Salween River Basin map.