الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
INTRODUCTION
1. NATURE OF THE PROBLEM
All reservoirs formed by dams on natural waterways
are subject to some degree of sediment inflow and deposition.
Sedimentation is considered a complex problem that
affects the reservoir’s behavior. Not all the sediment
passing a cross section moves according to the same la·.·s.
This is the most difficult aspect of sediment transport and
causes considerable confusion in solving such a problem.
Sediment deposition is a troublesome process along
natural streams and reservoirs, it raises stream beds,
increases flood heights and reduces reservoir capacities and
function. The sedimentation process in reservoirs follo·.,·s a
series of basic steps. First, sediment transported by the
upstream river system to a reservoir is transported at a
reduced rate farther into the reservoir, the distance being
dependent on the water velocities and the particle size. Tte
coarser sediments deposit in upper reaches while finer
sediments may travel into the reservoir and may reach the dam.
Also, if some sediment travels through the reservoir to the
dam, this may affect the operation of the outlet works. As
sediment accumulates in the reservoir, water storage capacity
is reduced. A major secondary effect is the downstrearc