A reservoir operation based on simple inflow prediction for flood control and water resources management in the Chi River Basin, Northeastern Thailand

Abstract

This study proposes a reservoir operation method based on simple dam inflow prediction for the Lampao Dam to inform flood control and water resources management in the Chi River Basin, Northeastern Thailand. With the proposed approach, dam inflows are predicted for the subsequent 7 days by formulating the relationship between 28 days of accumulated rainfall and inflows. The proposed inflow prediction method was able to predict the major floods in 2010 and 2011, and, based on the predictions, allowed reservoir operation to provide 100% of the volume needed for water use in all periods during the calculation period. In terms of flood control, the proposed operation method has enabled the maximum discharge in operation to be reduced compared to actual release discharge, thereby reducing the maximum inundation depth by up to 0.7 m in the lower basin in 2011. The results also indicated new areas that may experience increased maximum inundation, estimated to be up to a depth of 0.2 m; however, this was not expected to cause significant damage to the basin as a whole. A rapid increase in discharge was confirmed due to underestimation of inflow. Thus, better operation of the reservoir is possible using our improved rainfall monitoring method.