The Irrawaddy River or Ayeyarwady River (also spelt Ayeyarwaddy) is a river that flows from north to south through Burma (Myanmar). It is the country's largest river and most important commercial waterway. Originating from the confluence of the N'mai and Mali rivers, it flows relatively straight North-South before emptying through the Irrawaddy Delta into the Andaman Sea. Its drainage area of about 255,081 km covers a large part of Burma. After Rudyard Kipling's poem, it is sometimes referred to as 'The Road to Mandalay'. As early as the sixth century the river was used for trade and transport. Having developed an extensive network of irrigation canals, the river became important to the British Empire after it had colonised Burma. The river is still as vital today, as a considerable amount of (export) goods and traffic moves by river. Rice is produced in the Irrawaddy Delta, irrigated by water from the river. In 2007, Burma's military government signed an agreement for the construction of seven dams, yielding a total 13,360 kW, in the N'mai and Mali Rivers, including the 3,600 kW Myitsone Dam at the confluence of both rivers. Environmental organisations have raised concerns about the ecological impacts on the river's biodiverse ecosystems. Animals potentially impacted include the threatened Irrawaddy Dolphin.