Reseivoii􀀀 sedimentation is one of the most impoitaut problems, aud the more
complicated in fluvial hydraulics as a result of environmental man's activities. Tliis was the reason
that forced the researchers in that field to adopt special treatment for eveiy cases, as it was very
difficult to generalize the problem. The main objectives for this paper is to show, how one can
predict the sediment movement along a reservoir, and estimate the volume and shape of the
deposited sediments, which is considered as one of the factors that affects the reservoir usefiil life.
Hie High Aswan Dam Reservoir (Lake Nasser) case study in Egypt, wiU be treated in this paper.
Lake Nasser is characterized by the huge inlet sediment during the flood season, which on the
average amouuts to 134 MiUiou tonsper year. The application of one dimensional mathematical
model was tiied by the writer as an approach to evaluate the annual deposited sediment volume,
and detennine the sediment fi'ont progress. The estimated Lake dead storage life 408 years is
reasonable iu compaiison with the designed dead storage life, which was considered as 500 years
(Abu El Ata). The total reseivou life 1530 years, reflects the importance of such structure for the
development and improvement of the country. The paper explaius that for such a subject, it is
worthy and satisfactory to apply simple one dimensional mathematical models than to use more
comphcated models._