Nair, Rajan creator text xu| 2004 continuing ng p.35-37. More than 90 per cent of the annual runoff in penisular rivers and over 80 per cent of the annual runoff in the Himalayan rivers occurs between June and September. Many of the small rivers totally dry up during the summer. The depletion of forests has further aggravated the problem. - Reproduced. Water supply - India Water supply Yojana 180718