Abstract:
Effect of afforestation on storm flows for a catchment
situated between the lower Himalayan and Shivalik ranges has been
investigated. The catchment is shoe—shaped and encompasses an
area of 3076 sq.kms. It is drained by river Ramganga and its
tributaries. The area has been treated with eucalyptus and pine
plantation. A least squares regression is suggested to estimate
daily storm flow volumes from daily rainfall events after
analysing the data for six sub basins for the five years period
prior to the afforestation and for the five years of post
treatment period for events larger than 10mm of mean daily
rainfall. The results from the study indicate a decrease of 11%
to 36% in the daily storm flow volumes for the post treatment in
the five sub basins. However, there is no significant change in
one of the sub basins. The flow duration curves are also
presented for the catchment. The decrease in mean daily peak flow
which is available for 10% of time is by 15% and the mean daily
flow has decreased by 37%.
