Abstract:
The study of extreme hydrologic events is of great importance because of their socio-economic impacts. A great deal of time and efforts have been spent in predicting the occurrence and quantifying the effects of hydrologic extremes. However, these efforts have been mostly directed to flood studies and relatively less attention has been paid in studying drought. However, the increasing demands on available water resources and continued failure of monsoon over past 2-3 years have made the quantification and prediction of drought essential to water resources planning.
Drought is basically a phenomenon of low hydrologic extreme, which is synonymous with water deficit or water scarcity over a significant period of time and space. The water deficit refers to the choice of analysing either pre-
cipitation, soil moisture or streamflow. The hydrologists, and water resources planners are primarily concerned about
impacts due to drought (soil moisture or streamflow) than
the basic cause of drought (precipitation). For that reason,
the Institute launched a massive programme of undertaking hydrologic studies in drought affected states of the country. For analysing the impacts of drought on streamflow, studies were done using data of selected streamflow sites in Krishna basin and brief results of studies are presented in the present paper.