The Ayeyarwady River (Irrawaddy River) was started from the combination of two small rivers called Mayka and Malikha, which are sources of snow-capped mountains of the Himalayan mountain ranges at the northern most part. It flows from north to south through Myanmar in the centre, and divided into two parts as eastern and western.
Ayeyarwady is the country's largest river (1238 mile long), and the most important commercial waterway. It bisects into nine small rivers near the Irrawaddy Delta into the Andaman Sea. Its drainage basin of about 404,200 square kilometres (156,100sqmi) covers a large part of Burma. Furthermore, it is said that this river has existed for the past 45 million years. Most of the ancient capitals of Burma and its earliest forefather’s cities like Bagan, Tagaung, Sagaing, Ava can be found along this river. As early as the sixth century the river was used for trading and transport as well as for irrigation canals of agriculture and many dams.
However, many environmental organizations have raised concerns about the ecological impacts on the river's biodiversity. Certain animals potentially impacted include the threatened Irrawaddy dolphin (Orcaella brevirostris), wildlife, and other endangered species of birds. This is also impacting the fishermen in the area, who must rely on this river for cooperative fishing with dolphins, which can be seen in Myanmar.
There are three well-marked defiles between Myitkyina and Mandalay: first, about 65 kilometres (40mi) downstream from Myitkyinā is the first defile. Second one is below Bhamo, where the river makes a sharp westward swing, leaving the Bhamo alluvial basin to cut through the limestone rocks of the second defile. Between Katha and Kyauk Myaung is the third one. Overall, Irrawaddy river has five major tributaries.
Although the saltwater crocodile isn't commonly found in Burma, they do live in and near reserved forests surrounding the river, including Thameehla island, Meinmahla island, and others. The natural habitats of this central zone have been much altered for farming and there are few protected areas.
Today, the Irrawaddy is considered Myanmar's most important commercial waterway, especially the Irrawaddy Delta, one of the world's largest rice-growing areas.
Apart from that, the country is also one of the world's top exporters in Teak logs, which are floated down the river with large rafts. Many useful bridges, in total 14, are built across the Ayeyarwaddy river.
These days, many adventurous tourists traveling to Myanmar prefer to go on cruise tours along the Ayeyarwady river, which is playing a positive role in promoting the country as an emerging tourism hub.