Development of Decision-Making Support Tools for Future Reservoir Management Under Climate and Land Cover Variability: a Case Study

Abstract

The effects of climate change have been already experienced globally. The uncertainties of climate and land cover changes in the watershed above the reservoir have direct impacts on the inflow into the reservoir and the water resource management that uses reservoir rule curves. This study aims to assess the impacts of climate and land cover changes on the inflow into the Huai Luang Reservoir, Udonthani province during the period of 2018-2067 by using the simulation of two climate scenarios with the data from the PRECIS model under the emission conditions of B2. The prediction of future inflow has used the InVEST model. The improvement of the reservoir rule curves has used the Cultural Algorithm (CA) technique connected with the reservoir system simulation model. Monthly inflow data flowing into the reservoir from the past 33 years has been used to synthesize 1,000 events in order to evaluate the efficiency of the new obtained reservoir rule curves. Therefore, the data results of water shortage and excess water discharge situation have been illustrated in form of frequency, magnitude, duration of events, average amount of water, and maximum amount of water. The results have showed that average rainfall and temperature have tended to increase. The optimal reservoir rule curves improved by the CA technique can effectively reduce the frequency of water shortage situations and the one of the excess water discharge occurring during inflow changes in normal situation, and future situation under emission scenario B2.