This study focuses on estimating the flow discharges along the Nile River and its
tributaries in Sudan. Thus, a fifteen years' data record from the year 1983/1984 to
the year 1997/1998 was employed to estimate the transmission losses using the
water balance approach. The Nile River and its tributaries are divided into
subsequent reaches. The transmission losses are calculated as a percentage of the
inflow discharges to each reach. These losses were found to be 1% to 2% on the
Blue Nile, 2% to 7% on the White Nile, 1% on Atbara River, 1% to 3% on the
Main Nile. A spreadsheet model was then developed to calculate the average
annual flow discharges at Dongola Station on the Main Nile. Another data record of
nine years was used to validate the model. A good agreement was obtained between
the measured and calculated discharges. The results of this research could be a part
of a mutually acceptable modeling system in the Nile Basin region.