GREAT RIVERS OF MYANMAR: IRRAWADDY, SALWEEN, MEKONG

RIVERS OF MYANMAR

Salween River basin

The north-south flowing Irrawaddy River is Myanmar’s largest and most important commercial waterway. Navigable for 1,450 kilometers (900 miles), the Irrawaddy effectively divides Myanmar into two: east and west. The eastern part is more densely populated and contains the railroad and best roads. The western part is more isolate and can only be reached by ferry or riverboat as there are no bridges, except the Ava Bridge near Mandalay. The Irrawaddy’s annual flooding during the rainy seasons creates fertile banks, flood plains and deltas ideal of rice farming,

Other major rivers include the Chindwinn, the Sittong and the Salween (Thaanlwin) Two major rivers—the Irrawaddy and the Salween—originate in Tibet and the Himalayas and flow southward across the central plains. The Irrawaddy is Burma’s longest and most important river and a succession of Burma’s capitals were built within a short distance of its banks. To the east of the Irrawaddy, the much shorter Salween River drains the Shan Plateau and empties into the Gulf of Martaban between the ancient cities of Pegu and Thaton. [Source: Wikipedia]

Major rivers (by length in kilometers): Irrawaddy (shared with China) — 2,809 kilometers (1,745 miles); Salween river (shared with China and Thailand) — 3,060 kilometers (1,901 miles); Chindwin — 1,158 kilometers (720 miles); Mekong (shared with China Laos, Thailand, Cambodia, and Vietnam — 4,350 kilometers (2,702 miles). [Source: CIA World Factbook]

Major watersheds (area square kilometers): Indian Ocean drainage: Brahmaputra (651,335 square kilometers), Ganges (1,016,124 square kilometers), Irrawaddy (413,710 square kilometers), Salween (271,914 square kilometers); Pacific Ocean drainage: Mekong (805,604 square kilometers). [Source: CIA World Factbook]

Irrawaddy River

The Irrawaddy River (Ayeyarwady River) runs for about 2,100 kilometers (1,300 miles) from northern Myanmar to the Bay of Bengal, near Yangon, and is constantly changing. In the wet season, in some places, it fills with so much water it resembles a vast chocolate-brown lake. In the dry season, in the same places, the river level drops so low that the river bed resembles a desert of white sand dunes. [Source: Alexander Frater, Smithsonian, May 1984, the Observer]

Keeping navigators on their toes are sandbars that change by the day, and even the hour, and channels that are fifty feet deep in the morning and silt up and disappear by the evening. It is not surprising that many of the steam ships that travel on the river periodically run aground and get stranded for days at a time. Erosion along the river is so common place that each year villages collapse into the river and swallowed by the swirling brown water.

The Irrawaddy divides Myanmar in two. The eastern region is more densely populated and has better transportation links to Yangon. The western region is less densely populated and more rugged. Sometimes the only transportation links are by river. The middle portion of Myanmar is centered around the Irrawaddy River, with a large delta area at its mouth and the area above the delta featuring floodplains. Most of the population and agricultural lands are found along the Irrawaddy, which is navigable for about 1,600 kilometers (1000 miles). The Irrawaddy’s annual flooding during the rainy season makes its rich banks and delta the most fertile in Myanmar and ideal for rice paddy agriculture.

Irrawaddy Delta

Irrawaddy River route, watershed, cities and major tributaries

Irrawaddy Delta or Ayeyarwady Delta lies in the Irrawaddy Division, the lowest expanse of land in Myanmar. It that fans out from the limit of tidal influence at Myan Aung to the Bay of Bengal and Andaman Sea, 290 kilometers to the south at the mouth of the Irrawaddy River. The delta region is densely populated, and plays a dominant role in the cultivation of rice in rich alluvial soil as low as just three meters above sea level, although it also includes fishing communities in a vast area full of rivers and streams. In May 2008, the delta suffered a major disaster, devastated by Cyclone Nargis, which reportedly killed over at least 77,000 people with over 55,900 missing, and left about 2.5 million homeless. Portions of the low-lying delta—50,400 square kilometers, 19,500 square miles—were destroyed by Cyclone Nargis. [Source: Wikipedia]

The Irrawaddy Delta produces 65 percent of Myanmar’s rice. The region also is home to 80 percent of its aquaculture, 50 percent of its poultry and 40 percent of its pig production, according to the FAO. The area has numerous rivers and channels and much of the transport in and around the area is by boat. There are many creeks and streams. The rich alluvial soil is ideal for rice growing. Many fish are shrimp are available. Dried fish and shrimp from the region are used to make sauces and paste.

The Irrawaddy Delta comprises the main arms of Pathein River, Pyapon River, Bogale River, and Toe River. Mawtin Point, formerly Cape Negrais, is a famous landmark in the Irrawaddy Division, and it also marks the south west end of Myanmar. The highest point of the delta, Waphu Mount 404 meters (1,325 feet) lies between Pathein and Mawtin Zun (point), on the western strip of the delta. A major portion of the area is covered with low lying lands just three meters above sea level. This alluvial plain is bounded to the west by the Rakhine Yoma and to the east by the Bago Yoma. It is dissected into peninsulas and islands by the large southward flowing rivers which are subject to tidal intrusion. The lower seaward third of the delta is completely flat with no local relief and stretches for 130 kilometers from east to west.

The waters of these rivers are very turbid due to a heavy silt load they carry and the sea is very shallow with depths less than 5.5 meters across the coastline and in the east for a distance of up to 28 kilometers offshore. As a result of constant accretion into the sea, the delta is advancing at a rate of 5–6 kilometers per 100 years, equivalent to about 1,000 hectares per year.

Annual rainfall in the delta region is approximately 2,500 milimeters (100 inches), with a mean temperatures of 32 degrees C (90 degrees F). Most of the rain falls during the monsoons between mid-May and mid-November. It is cool and dry from mid-October to mid-February when temperatures begin to rise with premonsoon squalls in April and early May.

Salween River

The Salween River is powerful waterway even in the dry season. It runs 1,900 miles (3,060 kilometers) from the high Tibetan mountains to the Gulf of Martaban and the Andaman Sea, off Myanmar’s western coast. At Weigyi, on the border of Myanmar and Thailand, it produces a notorious whirlpool that is strong enough to pul a boat underwater. Locals leave offerings of rice, flowers and bananas to appease the god of the Salween and to thank him for vital water and prosperity he brings. The Salween is home to 70 species of fish including catfish, eel, featherback and carp who thrive in its surging rapids and deep pools. During the dry season the river dropes by 10 meters (33 feet) or more. [Source: Richard Lloyd Parry, The Times, March 23, 2006 ]

Three Parallel Rivers in Yunnan, China is a UNESCO World Heritage Site. Here the upper reaches of three of Asia's mightiest rivers—the Yangtze, Mekong, and the Salween—flow parallel to one another within a 55 mile band, divided by high mountain ridges. The Yangtze river, known in this area as the Jinsha, marks the boundary between Tibet and Kham. The Mekong is known as the Lancang. The Salween is called the Nujiang. “Jiang” is the Chinese word for river. The area is stunningly beautiful but rarely visited because the terrain carved by the rivers is so severe and rugged.

Fed by monsoon rains, the Yangtze, Mekong and Salween all sweep east of the Himalayas then drop due south, parallel to one another, before heading off in different directions. The gorges of the upper Yangtze, Mekong and Salween are among the deepest in the world, each twice the depth of the Grand Canyon, and reaching three kilometers in some places. Each gorge is separated from the others by towering mountains with more than a hundred peaks over 5,000 meters.

The Salween River flows undisturbed through some of the most outwardly tranquil territory on earth. It is Southeast Asia’s longest undammed waterway. But if the Myanmar government and the Chinese have their way it won’t be that way that way for long, turning parts of it into still-water lakes to which many of species that thrive in the river are ill-adapted.

In Myanmar much it flows through territory occupied by the Karen minority. “As long as I have lived here my family has been totally dependent on the Salween for our livelihood,” says Htoo Lwee, a member of the Karen ethnic group that lives in the village of Hoekey, a few miles below the proposed dam site at Weigyi. “The river gives us a living from fishing and from boating. It is our life and our mother. If the dam is constructed we will not be able to live.”

Mekong River

The Mekong River is one of the world's great rivers. Originating in Tibet, not far from the source of the Yangtze River, it tumbles down through the Himalayas and southern China into Southeast Asia and flows along the borders of Laos, Burma and Thailand through the heart of the Golden Triangle into Cambodia, where it flows in one direction in the wet season and the opposite direction in the dry season. It finally empties into the South China Sea at the Mekong Delta in Vietnam. Its source in Tibet as not discovered until 1994.

The Mekong River is shared by China, Thailand, Myanmar Laos, Cambodia, and Vietnam and goes by many names. It is known as Lancang Jiang (Turbulent River) in China, the Mae Nam Khong in Thailand, Myanmar and Laos, Tonle Than (Great Waters) in Cambodia and Cuu Long (Nine Dragons) in Vietnam. It is also known as River of Stone, Dragon Running River, Mother River Khong, and Big Water.

The Mekong is the longest river in Southeast Asia, the 12th longest in the world and the 10th largest in terns of volume. With about half of its length in China, it flows for 4,350 kilometers (2,703 miles) and provides food and water for 60 million people and disgorges 475 billion cubic meters of water each year into the South China Sea and the Pacific Ocean. It has a drainage area of 805,604 square kilometers (311,045 square miles).

Image Sources: Wikimedia Commons

Text Sources: The Irrawaddy, Myanmar Travel Information, burmalibrary.org, burmanet.org, “Encyclopedia of World Cultures Volume 5: East/Southeast Asia:” edited by Paul Hockings, 1993; National Geographic, New York Times, Washington Post, Los Angeles Times, Smithsonian magazine, Encyclopedia.com, Library of Congress, Live Science, The Conversation, The New Yorker, Time, BBC, CNN, Reuters, Associated Press, AFP, Lonely Planet Guides, Google AI, Wikipedia, The Guardian and various websites, books and other publications.

Last updated June 2026