Abstract:
Now a days, change in climate variables caused by natural and anthropogenic effects have
posed big problem on many water resource projects in our country. The main aim of this thesis
is to assess the impacts of climate change on stream flow and evaluation of reservoir
performances using Reliability, Resilience and Vulnerability indices (RRV). Hydrological data
(stream flow) and Meteorological data such as precipitation, temperature (Tmax, Tmin)
relative humidity and solar radiation in and around the study area used. And a recent
Representative Concentration Pathway (RCP) scenario was used for climate change impact
evaluation. Climate data (RCP2.6, RCP4.5 and RCP 8.5) were evaluated for the base and
future climate scenario which develop (1976-2005), (2021-2050) and (2051-2080). The HEC
HMS model was used to simulate the current and future inflow volume to the reservoir. The
model performance resulted in NSE = 0.76, R2 =0.78 and D= -3.17 during calibration. During
validation, NSE = 0.8 NSE, R2 =0.82 and D= 2.1 was obtained. The projected future climate
scenario shows an increasing trend for both maximum and minimum temperature however, for
the case precipitation decreasing trend for future scenarios. The average time base reliability
of the reservoirs was less than 50% for no reservoir condition and greater than 50% for the
other condition considered but volumetric reliability and resilience varies between 50% and
100% for all conditions. According to the vulnerability result the reservoirs will face shortage
of flow which ranges from 5.7% to 33.8%. Finally, HEC_ResSim model was used to evaluate
reservoir simulation and hydropower generation for different climate scenarios. The output
result of HEC_ResSim model was Maximum Average Energy generated for Upper Dam
349.4MWhr and 331.2MWhr for short and long term respectively and average Energy
generated for Lower Dam 4045.82 MWhr and 3946.74MWhr for short and long-term future
scenario, respectively. Generally for RCP scenarios, Both Tmax and Tmin are increasing
where precipitation and inflow to Reservoir is Decreasing Due to increasing of
Evapotranspiration. And there is a fluctuation of power generation with seasonal variation for
the wet season and dry season energy output and from impact of climate analysis the result
shows Variation (either decreasing or increasing) as compared to estimate by EEPPCO.
