The effect of reservoir geometry on reservoir routing methods.

Dams are usually built on narrow valleys to retain the largest amount of water in deep valleys. In Iraq there are two types of dams, gravity dams, usually built on narrow valleys, while embankment dams are built in less rugged lands. The goal of this research is to assess reservoir routing techniques, modified Pul's approach and the Kinematic wave models, in terms of developing hypotheses, applying mathematical formulae, the data required, as well as the benefits and drawbacks of employing them. As a way to compare the outcomes of the various approaches, two Iraqi reservoirs were chosen. Al-Adhaim dam is narrow, whereas the Haditha dam has a long and large storage basin. The reservoir's initial water level was established at the spillway crest level, and associated inflow hydrographs were chosen, as well as, the outflow dam control systems. From the results, it is clear that using the hydrological method does not give any accurate indication about the effect of the backwater curve at the upstream of the dam, or any branches entering or exiting the storage basin, so it can be used in dams with a narrow storage basin such as concrete dams. As for long and wide dams, it is preferable to use the hydraulic method because it is more accurate in hydraulic cases that occur at the upstream of the dam, such as backwater curve effects or branches. [ABSTRACT FROM AUTHOR]