A research on probability-based rule curves for multi-purpose reservoir systems in the Seine Revier Basin, France, has been accepted for publication in Water journal by Dr. Quan Dau, a member of the Climate Smart Lab, and his co-authors.


Multiple reservoir operation is of paramount importance due to tradeoffs in water supply and their cost functions. Understanding this complexity is important for optimizing water supply and increasing synergies gained from the joint operation. Therefore, this study aimed to develop a conceptual framework for addressing the effects of climate change on water security under the operating rules of the multiple reservoir system in Northern France. A Dynamic Programming approach (DP) was employed to perform the cost-benefit analysis that best fit with the objectives of reservoir operation, while the Space Rule was applied to balance the available space in each reservoir of a parallel system. A finite-horizon optimal regulation was then adopted for determining daily reservoir storage based on the probability-based rule curves. The results indicated that the predicted inflow during the drawdown-refill cycle period to the Marne and Panneciere reservoirs would be the largest and lowest, respectively. The proposed upper rule curves during high flow conditions suggested that the release from Aube reservoir should be postponed from July to August, until September. At 50- and 100-year return periods, a quite high release rate from Seine and Marne reservoirs was observed during the dry season. The decrease in future water supply from Panneciere reservoir was found during summer, while the withdrawal in November could cause excessive water in the Seine tributary and Paris City. Under low flow condition at all return periods, the proposed lower rule curves recommended that the reservoir storage should go below the current operating rule with a clear difference in July (the largest in Marne and the smallest in Panneciere), and almost no difference in November. Moreover, the web-based support system called “IRMaRA” was developed for revising operating rules of four main reservoirs located in the Seine River Basin. The novelty of this modeling framework would contribute to the practice of deriving optimal operating rules for a multi-reservoir system by the probability-based rule curve method. Based on the evaluation of the effects of applying the estimated reservoir storage capacity under different return periods, both less overflow and water shortage represented in different levels of quantity and severity can be expected as compared to the existing target storage at specified control points. Finally, the obtained finding revealed that the application of dynamic programming for reservoir optimization would help developing a robust operating policy for tackling the effects of climate change.

DOI: https://doi.org/10.3390/w15091732

Link: https://www.mdpi.com/2073-4441/15/9/1732