Abstract:
Floods due to failure of dams induce widespread damages to property and losses of
life and owing to its high magnitude and unpredictable sudden occurrence.
The objectives of the study is to analyze, and evaluate the impact of 100 year flood,
and probable maximum flood as inflow scenarios as well full reservoir pool sunny
day failure, the objectives of the study is achieved by using two computer models.
Upstream of the study dam , the catchment has been divided into three subbasins,
namely upper subbasin, upper left subbasin, and upper right subbasin, Hydrological
Engineering Center- Hydrological Model System developed for study area after
determining the initial parameters, such as probable maximum precipitation, and
one percent precipitation, the objective of hydrological model was to estimate
probable maximum flood , one chance flood , and the result of the two scenarios
applied to the dam in case of overtopping.
Hydrologic Engineering Center -River Analysis System used to determine water
surface profile, and simulate and predict peak flow, and outflow hydrograph for the
three scenarios, model is used for dam breach analysis , dam failure were analyzed
for probable maximum flood , one chance flood , and sunny day failure, breach
parameters are determined by using two methods ,Bureau of reclamation (1982)
and Thun Von & Gillette (1999).
The result of the hydrological models showed that, there is no overtopping for the
two scenarios , probable maximum flood, one chance flood, meanwhile the result of
hydraulic model indicate that peak flow , and outflow hydrograph depend on the
additional inflow, nature of the reservoir, and breach paraeters.
