A fisherman operates his boat at the mouth of the Citarum river north-west of Muara Gembong, West Java province, Indonesia. Indonesia's Citarum river burbles past terraced rice paddies and quiet farming villages in the highlands of West Java, as it begins to wind its way hundreds of kilometres towards the sea. REUTERS/Darren Whiteside

Students walk through rice fields located in Majalaya, a town densely populated with textile factories, south-east of Bandung, West Java province. But the charm evaporates swiftly as the river, often labelled the world's most polluted, descends past crowded zones of factories and homes that dump a pungent stew of garbage, waste and sewage into its 190-mile stretch. REUTERS/Darren Whiteside

Waste water at a textile factory is treated before being released into a stream that joins the Citarum river in Majalaya, south-east of Bandung, West Java province. Among the river's worst polluters are dozens of textile factories in Majalaya that dump chemical waste, said Arif Havas Oegroseno, a deputy minister who coordinates maritime affairs. REUTERS/Darren Whiteside

Children play along an old section of the Citarum river south of Bandung, West Java province. Long before it hits the sea on the eastern shores of Jakarta Bay, the river turns into a toxic cocktail the colour of coffee. REUTERS/Darren Whiteside

Farmers plant rice close to the Citarum river near Muara Gembong, West Java province. Children fly kites and play beside piles of floating trash in some parts of the river, but others avoid it as being a mere garbage dump. Yet further downstream, women in conical hats work in fields irrigated by the river. REUTERS/Darren Whiteside

Indonesian soldiers work during a clean-up operation along the Citarum river, south of Bandung, West Java province. Hundreds of soldiers were recently posted along the river to retrieve garbage, which gets burned as part of the ambitious programme backed by more than 10 ministries, local government, community groups, the police and the military.

REUTERS/Darren Whiteside

A farmer works in a rice paddy near a stream which flows into the Citarum river, in the mountains south of Bandung, near Pacet, West Java province. They are among the 28 million people who depend on the river waters, which supply Jakarta, support 988,422 acres of rice paddies, sustain fish farms and fill reservoirs that generate about 2 gigawatts of hydropower. REUTERS/Darren Whiteside

A woman and a child wash on the porch of a house located near the mouth of the Citarum river north-west of Muara Gembong, West Java province. REUTERS/Darren Whiteside

Environmental activist Deni Riswandani holds up cups of water from the Citarum river (R) and water from a tributary which runs through an area densely populated with textile factories (L) where the two meet near Majalaya, south-east of Bandung, West Java province. Activists and green groups blame the failure of the government's previous clean-up efforts on a lack of monitoring and difficulties enforcing regulations. REUTERS/Darren Whiteside

Men guide a boat carrying sand past where a section of the Citarum river is joined by a polluted tributary which runs through an area densely populated with textile factories near Majalaya, south-east of Bandung, West Java province. Greenpeace and several community bodies won a long court battle to revoke the permits of polluting factories in Rancaekek, on the outskirts of Bandung, where the group says pollution caused losses of 11.4 trillion rupiah ($831 million). REUTERS/Darren Whiteside

A worker collects sand from the bottom of the Citarum river in order to make bricks, near Majalay, south-east of Bandung, West Java province. REUTERS/Darren Whiteside

An Indonesian soldier burns trash collected from the banks of the Citarum river during a clean-up operation, south of Bandung, West Java province. REUTERS/Darren Whiteside

A woman washes fish near the mouth of the Citarum river north-west of Muara Gembong, West Java province. REUTERS/Darren Whiteside

A dead goat floats among garbage and debris towards the mouth of the Citarum river north-west of Muara Gembong, West Java province. REUTERS/Darren Whiteside

Farmers walk over a stream near Cisanti Lake, the main source of the Citarum river, in the mountains south of Bandung, in Tarumajaya village, West Java province. REUTERS/Darren Whiteside

Men fish at a polluted tributary, which runs through an area densely populated with textile factories and where it joins the Citarum river, near Majalaya, south-east of Bandung, West Java province. REUTERS/Darren Whiteside

Women wash clothes in water from a tributary of the Citarum river in Majalaya, a town densely populated with textile factories, south-east of Bandung, West Java province. REUTERS/Darren Whiteside

Floating fish farms are seen on the Jatiluhur Reservoir, part of the Citarum river basin, near Purwakarta, West Java province. REUTERS/Darren Whiteside

A woman pushes her scooter down a flooded street after heavy seasonal rains caused the Citarum river to flood in Dayeuhkolot, south of Bandung, West Java province. REUTERS/Darren Whiteside

A shop keeper chats with customers after heavy seasonal rains caused the Citarum river to flood in Dayeuhkolot, south of Bandung, West Java province. REUTERS/Darren Whiteside

Ferrymen guide a boat across the Citarum river, south-east of Muara Gembong, West Java province. REUTERS/Darren Whiteside

An Indonesian soldier cuts away garbage wrapped around the propeller on a pontoon boat during a clean-up operation along the Citarum river, south of Bandung, West Java province. REUTERS/Darren Whiteside

Rolls of cloth are stacked in the warehouse of a textile factory which has its own water treatment facilities located near the Citarum river in Majalaya, south-east of Bandung, West Java province. REUTERS/Darren Whiteside

A woman uses her mobile phone while walking in flood waters after heavy seasonal rains caused the Citarum river to flood in Dayeuhkolot, south of Bandung, West Java province. REUTERS/Darren Whiteside

Women board a small boat used as a ferry to cross the Citarum river south-east of Bandung, West Java province. REUTERS/Darren Whiteside

A woman sells salt water fish from the Java Sea near her roadside stand next to the Citarum river south-east of Muara Gembong, West Java province. REUTERS/Darren Whiteside

A fisherman sails his boat at the mouth of the Citarum river north-west of Muara Gembong, West Java province. REUTERS/Darren Whiteside

A combination photograph shows outdoor toilets along the stretch of the Citarum river before it enters the Java Sea north-west of Muara Gembong, West Java province. REUTERS/Darren Whiteside