Experiment was conducted to study the effects of different floating materials to reduce the evaporation losses from water storage structures. Different types of floating materials viz., hitlon sheet (4 mm), cotton oil, neem oil, burnt motor oil were used. It was found that minimum evaporation losses occurrepd in case of hitlon sheet followed by neem oil, cotton oil and burnt motor oil as compared to control treatment i.e. uncovered water. The reduction in evaporation in case of hitlon sheet, neem oil, cotton oil, and burnt motor oil as compared to control are found to be 93%, 10.55%, 7.88% and 5.35% respectively. The cost of saving of water per liter is found to be minimum in hitlon sheet (0.025 Rs./L) followed by burnt motor oil (0.11 Rs./L), Cotton oil (0.13 Rs./L) and maximum in neem oil (0.77 Rs./L). There was increase in the electrical conductivity of water in case of cotton oil, neem oil, burnt motor oil where as no significant change in hitlon sheet treatment. On the basis of this experiment the treatment of hitlon sheet is found to be most efficient, effective in reduction in evaporation losses (93%) with minimum cost of saving per liter of water (0.025 Rs./L), no significant adverse effect on quality of water and on material during experimental period.