High on a mountain in the Himalayas, the pristine headwater of the Bagmati river falls from the mouth of a tiger statue. For the Hindu majority nation, the river is long revered as having the power to purify souls. But Nepal's holiest river has deteriorated so greatly that today it is also the country's most polluted. (Aug. 17) (AP video/Upendra Mansingh and Niranjan Shrestha)