“The waters of the Ganga are pure and sparkling when it starts from Gangotri, with a BOD, that is, Biochemical Oxygen Demand, of zero, and a DO, Dissolved Oxygen, of over 10. Water with BOD level of less than 2mg per litre can be consumed without treatment; that with BOD level between 2 and 3 mg per litre can be consumed, but only after treatment; and that with BOD level above 3 mg per litre is unfit even for bathing. Ganga-Yamuna water at Sangam in Allahabad has a BOD level of 7.3 mg per litre! It is totally unfit even for bathing!!”
―
Rajnikant Puranik,
Nehru's 97 Major Blunders