A Flood Prediction Model for Adapting Flood Control Rule Curves of a Multipurpose Dam

The present paper proposes a flood prediction model to improve the flood control performance of the FCRCs by adjusting them to suit each predicted flow hydrograph. The model applies the ratio of cumulative flows of preceding day over that of today to estimate the volume characteristic of flood hydrograph. The volume estimate is then used for describing its associated peak discharge property. The model subsequently selects a design flood whose volume and peak discharge agree well with the model estimates as its predicted flood. The proposed flood prediction model was developed to adapt the existing FCRCs of the multipurpose Ubolratana Dam (Pong River Basin, Thailand) using the series of 35 yr (1970 2004) observed daily inflows. The model assessment results have shown that the FCRCs adapted to the predicted flood perform better than the current FCRCs for various floods with return periods ranging from > 10,000 yrs to 200 yrs because they prevent areas downstream from being flooded.