There are four reservoirs in a series located on the Be River of the Dong Nai River Basin in Southern Vietnam. The primary purpose of the three upstream reservoirs is hydropower generation; however, the fourth one plays a vital role in water supply and irrigation. The management of the water resources related this river to date has been restricted mostly to hydropower. Nevertheless, the increasing water demands for households, industry and agriculture may potentially be met by improved water management policies. This study therefore recommends a better strategy for hydropower generation to increase the amount of energy that will be generated and to mitigate the water supply shortage.
The GWASIM model (Chou and Wu 2010) is applied in this paper, which is based on Network Flow Programming, to simulate the daily hydropower generation and water resource allocation for the system. The model set up includes the main river and tributaries with 33 years of inflow data and demand requirements for the year 2015. Regulation strategies for hydropower generation of cascade reservoirs were evaluated and compared. Strategies and scenarios of different water allocation priorities and rations were also simulated and compared.
The results showed that when domestic and industrial demand has the first priority access to water, and energy generation comes second, the shortage index of all demands was reduced and the hydropower generation was essentially the same in both strategies. This improved strategy for operating cascade reservoirs can improve energy production from hydropower as well as water supply for domestic demand and irrigated food production.

1. Barr, R. S., Glover, F., & Klingman, D. (1974). An improved version of the out-of-kilter method and a comparative study of computer codes. Mathematical programming, 7(1), 60-86.
2. Celeste, A. B., & Billib, M. (2009). Evaluation of stochastic reservoir operation optimization models. Advances in Water Resources, 32(9), 1429-1443.
3. Chen, J., Guo, S., Li, Y., Liu, P., & Zhou, Y. (2013). Joint operation and dynamic control of flood limiting water levels for cascade reservoirs. Water Resources Management, 27(3), 749-763.
4. Dhar, A., & Datta, B. (2008). Optimal operation of reservoirs for downstream water quality control using linked simulation optimization. Hydrological processes, 22(6), 842-853. doi: 10.1002/hyp.6651
5. Fang, H.-b., Hu, T.-s., Zeng, X., & Wu, F.-y. (2014). Simulation-optimization model of reservoir operation based on target storage curves. Water Science and Engineering, 7(4), 433-445.
6. Fu, X., Li, A., Wang, L., & Ji, C. (2011). Short-term scheduling of cascade reservoirs using an immune algorithm-based particle swarm optimization. Computers & Mathematics with Applications, 62(6), 2463-2471.
7. Fulkerson, D. R. (1961). An out-of-kilter method for minimal-cost flow problems. Journal of the Society for Industrial and Applied Mathematics, 9(1), 18-27.
8. Guo, S., Chen, J., Li, Y., Liu, P., & Li, T. (2011). Joint operation of the multi-reservoir system of the Three Gorges and the Qingjiang cascade reservoirs. Energies, 4(7), 1036-1050.
9. Howson, H., & Sancho, N. (1975). A new algorithm for the solution of multi-state dynamic programming problems. Mathematical programming, 8(1), 104-116.
10. Jiang, Y., Hu, T., Huang, C., & Wu, X. (2007). An improved particle swarm optimization algorithm. Applied Mathematics and Computation, 193(1), 231-239.
11. Ko, S. K., Fontane, D. G., & Labadie, J. W. (1992). Multiobjective Optimization of Reservoir Systems Operation: Wiley Online Library.
12. Koutsoyiannis, D., & Economou, A. (2003). Evaluation of the parameterization‐simulation‐optimization approach for the control of reservoir systems. Water resources research, 39(6).
13. Labadie, J. W. (2004). Optimal operation of multireservoir systems: state-of-the-art review. Journal of water resources planning and management, 130(2), 93-111.
14. Linsley, R. K., Franzini, J. B., Freyberg, D. L., & Tchobanoglous, G. (1992). Water resources engineering.
15. Mays, L. W. (2010). Water resources engineering: John Wiley & Sons.
16. Olivares, M. A. (2008). Optimal hydropower reservoir operation with environmental requirements. University Of California Davis.
17. Oliveira, R., & Loucks, D. P. (1997). Operating rules for multireservoir systems. Water resources research, 33(4), 839-852.
18. Rani, D., & Moreira, M. M. (2010). Simulation–optimization modeling: a survey and potential application in reservoir systems operation. Water Resources Management, 24(6), 1107-1138.
19. Reis, L., Walters, G., Savic, D., & Chaudhry, F. (2005). Multi-reservoir operation planning using hybrid genetic algorithm and linear programming (GA-LP): An alternative stochastic approach. Water Resources Management, 19(6), 831-848.
20. Ringler, C., & Nguyen, V. H. (2004). Water allocation policies for the Dong Nai River Basin in Vietnam: an integrated perspective. Environment and Production Technology Division Discussion Paper(127).
21. SIWRP. (2009). Proposal reservoir operation of Dong nai-Sai Gon basin to mitigate flood for Ho chi Minh city, Vietnam (in Vietnamese).
22. SIWRP. (2010). Integrated water resources planning for Dong Nai River Basin (in Vietnamese).
23. Sreenivasan, K., & Vedula, S. (1996). Reservoir operation for hydropower optimization: a chance-constrained approach. Sadhana, 21(4), 503-510.
24. Suiadee, W., & Tingsanchali, T. (2007). A combined simulation–genetic algorithm optimization model for optimal rule curves of a reservoir: a case study of the Nam Oon Irrigation Project, Thailand. Hydrological processes, 21(23), 3211-3225. doi: 10.1002/hyp.6528
25. Wurbs, R. A. (1993). Reservoir-system simulation and optimization models. Journal of water resources planning and management, 119(4), 455-472.
26. Yeh, W. W. G. (1985). Reservoir management and operations models: A state‐of‐the‐art review. Water resources research, 21(12), 1797-1818.
27. Young, G. K. (1967). Finding reservoir operating rules. Journal of the Hydraulics Division, 93(6), 297-322.
Zhou, Y., Guo, S., Liu, P., & Xu, C. (2014). Joint operation and dynamic control of flood limiting water levels for mixed cascade reservoir systems. Journal of Hydrology, 519, Part A, 248-257