Result of operational cloud seeding experiment over Rihand catchment in northeast India

A cloud seeding experiment, on operational basis, was undertaken during August-September, 1973 over the catchment area of the Rihand reservoir In the state of Uttar Pradesh, While the intended seeding operation was done on many days, the same could not be accomplished, for unavoidable reasons, on a number of days during the above period. Considering the latter category of days as control days and the areas adjoining the cases involving the catchment as control areas, the result of the experiment was evaluated. The analysis suggested rainfall increase in the catchment area, due to seeding, by over 17 per cent. The increase, however, is statistically not significant.