Improved tradeoffs in operation of multi-purpose reservoir by considering medium-range operational ensemble forecast

Potential improvement in tradeoffs among the operation purposes of a multi-purpose reservoir by introducing adaptive operation considering medium-range operational ensemble hydrological forecast was investigated in this study. One-week Ensemble Forecast of precipitation provided by Japan Meteorological Agency (JMA) was employed in this study. Effects and impacts on reservoir operation purposes such as flood management, water supply and hydropower production were analysed when adaptive reservoir operation based on JMA’s One-week Ensemble Forecast of precipitation was conducted. It was shown in the case studies with the Hiyoshi Reservoir in the Katsura River basin in Japan that effects in flood control of the reservoir can be increased by introducing medium-range ensemble forecast without significantly decreasing its functions for water supply and hydropower, improving tradeoffs among the different operation purposes of the reservoir.