Abstract:
Streamflow appraisal in time and space particularly in semi arid and dry sub humid
regions has vital importance in the formulation of round the year plan of water uses comprising
domestic & industrial water supply, irrigation scheduling, reservoir operation, in-stream flow
maintenance etc. Drought severity analysis including the estimation of flow availability, drought
duration, and deficit volume etc. was carried out using the 20–42 years (1960–2001) 10-daily
streamflow data of five sites on the Betwa River system and. independent streamflow drought
events were described by pooling the data, and severity of an independent drought event
classified using a new drought severity index (DSIe) defined as a function of (1) the ratio of
deficit flow volume to corresponding volume at the truncation level and (2) the ratio of duration
of deficit flow to the maximum possible duration of the independent streamflow drought event.
The study found that the upper reaches of river course were more prone to severe droughts than
were the lower reaches. The drought events starting during August−November were more likely
to be severe drought events than those in the other months.
