I want to suggest the multipurpose solution for preventing the evaporation of the stored water in Dam’s & other Reservoirs.
This is Azolla, a floating fern which is a good portentous diet for the cattle’s, Fish & other mammal’s, if we plant these fern on the surface of the reservoir, we would definitely be preventing the evaporation process of the water stored. The plantation process shall be carried out immediately after the monsoon gets over but before the winter ends since this fern does not cultivate above 35 deg. temperature.