Optimal reservoir operation for water supply in dry season

MINISTRY OF EDUCATION AND TRAINING MINISTRY OF AGRICULTURE AND RURAL DEVELOPMENT THUYLOI UNIVERSITY ************** OPTIMAL RESERVOIR OPERATION FOR WATER SUPPLY IN DRY SEASON: THE CASE STUDY OF CUA DAT RESERVOIR IN THE CHU-MA RIVER SYSTEM THANH HOA PROVINCE TRINH XUAN MANH MSc Thesis December 2014 Optimal reservoir operation for water supply in dry season: the case study of Cua Dat Reservoir in the Chu – Ma river system Thanh Hoa province Master of science thesis By Trinh Xuan Manh Supervisor Dr Nguyen Mai Dang HA NOI December 2014 This research is finished for the partial fulfillment of requirements for the Master of science degree at Thuy Loi University, Ha Noi, Vietnam (This Master Programme is supported by NICHE-VNM106 project) DECLARATION I hereby certify that the work which is being presented in this thesis entitled, “Optimal reservoir operation in dry season: the case study of Cua Dat Reservoir in the Ma-Chu River system, Thanh Hoa province” in partial fulfillment of the requirement for the award of the Mater of Science on Integrated Water Resource Management, is an authentic record of my own work carried out under supervision of Dr Nguyen Mai Dang The matter embodied in this thesis has not been submitted by me for the award of any other degree or diploma Date: … /12/2014 i Abstract Water supply of reservoirs and especially reservoirs used for irrigation, hydropower, aquaculture, navigation, environment…in the dry season are often troubled due to increasing water demands according to the economic development and society, while the flow to the reservoir is limited In recent years, the depletion of the river flow during the dry season occurs more frequently and at a more intense level This is partly due to forest coverage reduction in the upstream of river basins, and partly due to the effects of climate change Hence, computation of the optimum water supply of reservoir for the water demands in the dry season is needed This study presents the initial research on applying Fuzzy Logic Algorithm for optimal operation of water supply in the dry season of 2011-2012 of the Cua Dat Reservoir in the Chu River basin, Thanh Hoa province The Cua Dat Reservoir is a multi-purpose reservoir for the following tasks: flood prevention, water supply, irrigation, power generation, and environmental flows In addition, MIKE 11 model is also used to simulate the release from the reservoir to the downstream to evaluate the efficiency of the optimal method The research used Fuzzy Logic algorithm based on the rule, the principle of "IF - THEN" and built the membership functions for the input variables: water level, inflow to the reservoir, the water demands, and discharge from the reservoir It is developed for the Fuzzy operating systems for the Cua Dat Reservoir and is meant to determine the optimal discharge process in case of shortage of water in the dry season Inflows, releases and water levels of the Cua Dat Reservoir were collected from actual operation of the reservoir For water demand of stakeholders, the author determined that the total water demand for whole area was about 4547 Mi.m3 For hydropower based energy production water is used at the largest rate (67% of total water demand), while domestic purposes water is obtained smallest rate of water use of the Cua Dat Reservoir Finally, the results from optimal method, the reservoir can meet 80% of water demand more than actual release throughout the dry season of 2011-2012 The initial research has been successful and the results showed that this method can be applied well to the optimal reservoir operation in Vietnam Key words: Cua Dat, reservoir operation, optimization, Fuzzy Logic, water demand, Fuzzy rule, MIKE 11 model Trinh Xuan Manh MSc Thesis ii Acknowledgement First of all, I would like to give a big thank to all people who have supported and assisted me during the Master Thesis Research Thanks for their support, encouragement and guidance that allowed me to complete this study in time Especially, I would like to express my appreciation to Dr Nguyen Mai Dang, my supervisor, for his unlimited encouragement, guidance, comments and technical supports on the Fuzzy Logic approach and other models as well as the thesis writing process from the beginning of the thesis research I would like to thank NICHE-VNM-106 project from the Government of the Netherlands for their financial support during the MSc study in the ThuyLoi University I thank to Mrs Hoang Nguyet Minh and Mrs Vu Thi Thuy Ngan who made a linkage between me and NICHE I also would like to thank Assoc Prof Dr Nguyen Thu Hien, Dean of the Faculty of Water Resources Engineering, for her help and comments during the Master study in the ThuyLoi University I wish to thank Dr Ilyas Masih and Ms Martine Rutten for their feedback, references and support from the proposal process I also wish to thank Mrs Mariette Van Tilburg, my English teacher, for her comments and support from the final thesis report I also want to thank the ThuyLoi University (TLU), Song Chu Irrigation Company, National center for Hydro-Meteorological Service (HMS) for providing me very useful data sets Thanks to all of my colleagues at the HaNoi University of Natural Resources and Environment in Vietnam for your assistance in the last two years You will always be in my mind Last but not least, I want to take this opportunity to show my appreciation to my family, my close friends for their inspiration and support throughout my life; this research is simply impossible without you Trinh Xuan Manh MSc Thesis iii Table of Contents CHAPTER I: INTRODUCTION I.1 Background I.2 Problem statement I.3 Objectives and Research questions I.3.1 Objectives of the study I.3.2 Research Questions I.4 Structure of the thesis CHAPTER II: LITERATURE REVIEW II.1 Studies on reservoir operation using optimal theory II.2 Fuzzy logic theory II.3 Overview of hydraulic and hydrological modeling II.4 MIKE model 11 CHAPTER III: THE STUDY AREA 13 III.1 Description of the study area 13 III.1.1 Location of the study area 13 III.1.2 River network 14 III.1.3 Topographical characteristics 16 III.1.4 Geological, land and vegetable characteristics 18 III.2 Climate and hydrological condition 18 III.2.1 Climate condition 18 III.2.2 Hydrological condition 23 III.3 Population and economic characteristics 23 III.3.1 Population of the study area 23 III.3.2 Economic characteristics 24 III.4 Description of the Cua Dat Reservoir 24 CHAPTER IV: DATA AND METHODOLOGY 29 IV.1 Data collection 29 IV.1.1 Meteorological data 30 IV.1.2 Hydrological data 32 IV.1.3 Cua Dat reservoir operation data 34 IV.1.4 Determining total water demand 35 IV.2 Optimal analysis and Fuzzy logic approach for Reservoir operation 50 IV.2.1 Methods using in optimal reservoir operation 50 IV.2.2 Objective functions and constraints 53 IV.2.3 Using Fuzzy logic technique to optimize the Cua Dat reservoir operation54 IV.3 Hydraulic and hydrological model setup 62 IV.3.1 Determination of the model inputs 62 IV.3.2 Model setup 63 IV.3.3 Model calibration and validation 65 Trinh Xuan Manh MSc Thesis iv CHAPTER V: RESULTS AND DISCUSSIONS 73 V.1 Optimizing the Cua Dat reservoir operation 73 V.2 Routing the release to the downstream 74 CHAPTER VI: CONCLUSIONS AND RECOMMENDATIONS 77 VI.1 Conclusions 77 VI.2 Recommendations 78 REFERENCES 80 APPENDICES i Trinh Xuan Manh MSc Thesis v List of Figures Figure 2-1: Relationship between the various representations of a model 10 Figure 3-1: Location of study in the Thanh Hoa province in Viet Nam .13 Figure 3-2: Ma – Chu River Network in Viet Nam .16 Figure 3-3: Digital Elevation Model (DEM) of Thanh Hoa province 17 Figure 3-4: The location of the Cua Dat Reservoir on Ma-Chu river system .26 Figure 3-5: The main dam of the Cua Dat Reservoir 28 Figure 3-6: The spillway of the Cua Dat Reservoir 28 Figure 3-7: The storage of the Cua Dat Reservoir 28 Figure 3-8: The intake tower of the Cua Dat Reservoir 28 Figure 3-9: The gate of spillway of the Cua Dat Reservoir 28 Figure 3-10: The Bai Thuong weir 28 Figure 4-1: Distribution of monthly rainfall pattern at Thanh Hoa station 30 Figure 4-2: Distribution of monthly air temperature at Thanh Hoa station 31 Figure 4-3: Distribution of monthly average evaporation at Thanh Hoa station in 2011 & 2012 31 Figure 4-4: Distribution of relative humidity at Thanh Hoa station in 2011 & 2012 32 Figure 4-5: Annual discharge of the Cam Thuy and Cua Dat station 33 Figure 4-6: Schematization of hydrological station network 34 Figure 4-7: Monthly average discharge of Turbin of hydropower plant in years of 2011, 2012 and 2013 35 Figure 4-8: Inflow discharge of the Cua Dat reservoir in 2011 and 2012 35 Figure 4-9: Seasonal period and chart of water requirement of Spring paddy in 2011 39 Figure 4-10: Seasonal period and chart of water requirement of winter paddy in 2011 41 Figure 4-11: Seasonal period and chart of water requirement of sugar cane in 2011 42 Figure 4-12: Water use structure of whole downstream area of the Cua Dat reservoir in 2011 48 Figure 4-13: General flow chart of optimal reservoir operation in dry season .52 Figure 4-14: Fuzzy inference system for Fuzzy Mamdani 56 Figure 4-15: Transformation of input variable to membership value 57 Figure 4-16: Membership function for reservoir level for Fuzzy Mamdani model 58 Figure 4-17: Membership function for inflow for Fuzzy Mamdani model 58 Figure 4-18: Membership function for water demand for Fuzzy Mamdani model .59 Figure 4-19: Membership function for release for Fuzzy Mamdani model 59 Figure 4-20: Fuzzy rules base for operation of Cua Dat reservoir 60 Trinh Xuan Manh MSc Thesis vi Figure 4-21: Process of application, implication and aggregation 61 Figure 4-22: Hydraulic network of the Ma – Chu river basin .65 Figure 4-23: Observed and simulated hydrograph at Cua Dat station in 2006 .67 Figure 4-24: Observed and simulated hydrograph at Cua Dat station in 2008 .68 Figure 4-25: Observed and simulated hydrograph of water level at Ly Nhan Station in 2006 69 Figure 4-26: Observed and simulated hydrograph of water level at Xuan Khanh Station in 2006 69 Figure 4-27: Observed and simulated hydrograph of water level at Giang Station in 2006 70 Figure 4-28: Observed and simulated hydrograph of water level at Ly Nhan Station in 2008 71 Figure 4-29: Observed and simulated hydrograph of water level at Xuan Khanh Station in 2006 71 Figure 4-30: Observed and simulated hydrograph of water level at Giang Station in 2006 72 Figure 4-31: Structure of fuzzy system for Cua Dat reservoir 73 Figure 4-32: Comparison of water demand and fuzzy and actual releases 74 Figure 5-1: Hydrograph of optimal operation at the Bai Thuong weir 75 Figure 5-2: Hydrograph of optimal operation at the Xuan Khanh station 75 Figure 5-3: Hydrograph of optimal operation at the Giang station .76 Trinh Xuan Manh MSc Thesis vii List of Tables Table 3-1: Distribution of natural areas according to provincial border of the Ma river basin (ha) 14 Table 3-2: Characteristics of river shape of some large tributaries .15 Table 3-3: Average annual rainfall for many years at some stations of the Ma river basin 19 Table 3-4: Annual rainfall characteristics 20 Table 3-5: Monthly and annual wind speed at some stations of the Ma river basin (m/s) 21 Table 3-6: Average monthly temperature for many years at some stations 22 Table 3-7: Monthly average evaporation of some stations of the Ma River Basin .22 Table 3-8: Some main parameters of the Cua Dat Reservoir 25 Table 4-1: Kinds of data have been used in the study 29 Table 4-2: Crop distribution of different cultivated area in downstream of the Cua Dat reservoir 36 Table 4-3: Plant coefficients of paddy 39 Table 4-4: Plant coefficients of other plants 39 Table 4-5: Water requirement of Spring paddy in 2011 40 Table 4-6: Water requirement of winter paddy in 2011 41 Table 4-7: Water requirement of sugar cane in 2011 42 Table 4-8: Monthly water demand of agriculture of whole area in the Cua Dat reservoir downstream in 2011 .44 Table 4-9: Water demand of industrial production at downstream of the Cua Dat reservoir 45 Table 4-10: Domestic water demand of downstream area 46 Table 4-11: Structure of water use of whole area in 2011 .48 Table 4-12: Water demands and inflows in ten-day period in 2011 .49 Table 4-13: List of tributary basin on the Ma – Chu river basin 64 Table 4-14: Results of MIKE 11HD model calibration at Ma-Chu river basin in 2006 70 Table 4-15: Results of MIKE 11HD model validation at the Ma-Chu river basin in 2008 72 Table 4-16: The NASH for calculation of alternatives 74 Table 5-1: Flow characteristics at the Chu River downstream using optimal operation 76 Trinh Xuan Manh MSc Thesis vi Months Decades Stages Kc coeff ETc ETc Eff rain Irr Req mm/day mm/dec mm/dec mm/dec Nov Mid 1.24 3.44 34.4 43.6 Nov Mid 1.24 3.17 31.7 41.9 Nov Mid 1.24 2.97 29.7 36.6 Dec Mid 1.24 2.78 27.8 31.2 Dec Mid 1.24 2.58 25.8 26.5 Dec Mid 1.24 2.39 26.3 20.1 6.1 Jan Mid 1.24 2.2 22 12.2 9.8 Jan Mid 1.24 2.01 20.1 5.3 14.8 Jan Mid 1.24 2.06 22.7 17.6 Feb Late 1.22 2.09 20.9 4.6 16.3 Feb Late 1.18 2.06 20.6 3.2 17.4 Feb Late 1.13 2.12 16.9 5.9 11 Mar Late 1.09 2.16 21.6 10 11.6 Mar Late 1.04 2.18 21.8 12.8 9.1 Mar Late 0.98 2.44 26.9 11.1 15.8 Apr Late 0.93 2.66 26.6 5.9 20.7 Apr Late 0.88 2.85 28.5 3.2 25.3 Apr Late 0.83 2.99 29.9 14.3 15.6 May Late 0.79 3.11 28 26.1 1145.4 1131.5 200.4 Total Trinh Xuan Manh MSc Thesis vii Figure A-6: Seasonal period and chart of water requirement of Maize in 2012 Table A-6: Water requirement of Maize in 2012 Months Decades Stages Kc coeff ETc ETc Eff rain Irr Req mm/day mm/dec mm/dec mm/dec May Init 0.3 1.3 7.8 23.8 May Init 0.3 1.35 14.8 40.9 Jun Deve 0.37 1.73 17.3 41.5 Jun Deve 0.62 2.98 29.8 44 Jun Deve 0.87 4.16 41.6 44.3 Jul Mid 1.12 5.28 52.8 43.8 Jul Mid 1.19 5.55 55.5 44 11.5 Jul Mid 1.19 5.35 58.8 46.7 12.1 Aug Mid 1.19 5.14 51.4 50.1 1.3 Aug Late 1.17 4.87 48.7 52.7 Aug Late 0.94 3.72 41 53.6 Sep Late 0.64 2.44 24.4 55.4 Sep Late 0.42 1.52 9.1 34.2 453 575.1 33.9 Total Trinh Xuan Manh MSc Thesis viii Figure A-7: Seasonal period and chart of water requirement of Sweet Potatoes in 2012 Table A-7: Water requirement of Sweet Potatoes in 2012 Months Decades Stages Kc coeff ETc ETc Eff rain Irr Req mm/day mm/dec mm/dec mm/dec Oct Init 0.5 1.61 1.6 4.7 1.6 Oct Init 0.5 1.5 16.5 44.8 Nov Init 0.5 1.39 13.9 43.6 Nov Deve 0.56 1.44 14.4 41.9 Nov Deve 0.77 1.86 18.6 36.6 Dec Deve 0.99 2.22 22.2 31.2 Dec Mid 1.15 2.4 24 26.5 Dec Mid 1.16 2.23 24.5 20.1 4.4 Jan Mid 1.16 2.05 20.5 12.2 8.3 Jan Mid 1.16 1.87 18.7 5.3 13.5 Jan Late 1.14 1.9 20.9 15.9 Feb Late 1.03 1.76 17.6 4.6 13 Feb Late 0.9 1.58 15.8 3.2 12.5 Trinh Xuan Manh MSc Thesis ix Months Decades Stages Kc coeff Feb Late ETc ETc Eff rain Irr Req mm/day mm/dec mm/dec mm/dec 0.79 1.49 Total 8.9 4.4 238.2 284.3 75.2 Table A-8: Monthly water demand of agriculture of whole area in the Cua Dat reservoir downstream in 2012 Water demand of Bac Song Chu cultivated area in 2012 Months 10 11 12 Year Q(m3/s) 12.7 15.1 16.0 17.1 12.7 26.6 18.9 8.03 4.01 5.19 8.03 33.5 14.8 W(106m3) 34.5 36.9 43.4 44.1 34.5 69.0 51.0 21.9 11.4 14.8 21.2 90.2 473.8 Water demand of Nam Song Chu cultivated area in 2012 Months 10 11 12 Year Q(m3/s) 42.4 42.7 61.3 57.1 22.3 0.226 16.3 0.117 0.389 0.489 0.231 14.5 21.5 W(106m3) 113.7 103.3 164.2 148.1 59.8 0.6 43.6 0.3 1.0 1.3 0.61 39.0 675.9 Water demand of agriculture of whole area in 2012 Months 10 11 12 Year Q(m3/s) 55.2 57.8 77.4 74.1 35.0 26.8 35.2 8.15 4.39 5.68 8.27 48.1 36.3 1149 W(106m3) 148.3 140.2 Trinh Xuan Manh MSc Thesis 207.7 192.6 94.3 69.5 94.7 22.2 12.4 16.1 21.8 129.2 x Appendix 2: Water demand in ten-day period in year of 2012 Table A-9: Water demand in ten-day period in 2012 Period in ten-day unit Months Jan 1-10 Jan 11-20 Jan 21-31 Feb 1-10 Feb 11-20 Feb 21-28 Mar 1-10 Mar 11-20 Mar 21-31 Apr 1-10 Apr 11-20 Apr 21-30 May 1-10 May 11-20 May 21-31 Jun 1-10 Jun 11-20 Jun 21-30 Jul 1-10 Jul 11-20 Jul 21-31 Aug 1-10 Aug 11-20 Aug 21-30 Sep 1-10 Sep 11-20 Sep 21-31 Trinh Xuan Manh MSc Thesis Demand in M.m3 73.57 59.08 63.18 83.53 87.92 79.82 87.19 86.16 96.58 71.40 101.15 55.45 50.53 59.67 102.33 112.62 107.10 48.04 46.21 60.94 72.50 37.00 63.07 100.00 112.11 124.16 118.82 xi Period in ten-day unit Months Oct 1-10 Oct 11-20 Oct 21-31 Nov 1-10 Nov 11-20 Nov 21-30 Trinh Xuan Manh MSc Thesis Demand in M.m3 121.28 120.93 131.08 115.59 106.62 119.59 xii Appendix 3: Observed and calculated data of inputs and outputs in the Fuzzy system 3000 Discharge (m3/s) 2500 2000 1500 1000 500 0 50 100 150 200 2011 250 300 2012 350 Days Figure A-8: Average daily discharge into the Cua Dat Reservoir in 2011 and 2012 105,00 Water level (m) 100,00 95,00 90,00 85,00 80,00 75,00 51 101 151 201 Days 251 301 351 Figure A-9: Average daily water level of the Cua Dat Reservoir in 2011 105 Water level (m) 100 95 90 85 80 75 70 51 101 151 201 Days 251 301 351 Figure A-10: Average daily water level of the Cua Dat Reservoir in 2012 Trinh Xuan Manh MSc Thesis xiii 160,00 140,00 Turbin discharge (m3/s) 120,00 100,00 80,00 60,00 40,00 20,00 0,00 21 41 61 81 101 121 141 161 181 201 221 241 261 281 301 321 341 361 Days Figure A-11: Average daily turbin discharge of the Cua Dat hydropower plant in 2012 14,00 Turbin discharge(m3/s) 12,00 10,00 8,00 6,00 4,00 2,00 13 25 37 49 61 73 85 97 109 121 133 145 157 169 181 193 205 217 229 241 253 265 277 289 301 313 325 337 349 361 0,00 Days Figure A-12: Average daily turbin discharge of the Cua Dat hydropower plant in 2011 Trinh Xuan Manh MSc Thesis xiv Appendix 4: Inputs of MIKE 11 HD model 3000 2500 Dischagre (m3/s) Cam Thuy Cua Dat 2000 1500 1000 500 51 101 151 201 Days 251 301 351 Figure A-13: Average daily discharge at the Cam Thuy and Cua Dat station in 2006 10 Water Level (m3/s) Kim Tan Hoang Tan -2 51 101 151 201 251 301 351 Days Figure A-14: Average daily water level at the Hoang Tan and Kim Tan station in 2006 Trinh Xuan Manh MSc Thesis xv 4000 3500 3000 Discharge (m3/s) Cam Thuy 2500 Cua Dat 2000 1500 1000 500 51 101 151 201 Days 251 301 351 Figure A-15: Average daily discharge at the Cam Thuy and Cua Dat station in 2008 14 12 Water level (m) 10 Kim Tan Hoang Tan 51 101 151 201 251 301 351 -2 Days Figure A-16: Average daily water level at the Hoang Tan and Kim Tan station in 2008 Trinh Xuan Manh MSc Thesis xvi Appendix 5: Fuzzy rules base for the Cua Dat Reservoir No 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 If If If If If If If If If If If If If If If If If If If If If If If If If If If If If If If If If If If If If If If If If Res.levels Med.High Low.med Low.med Low.med Low.med Low.med Low Medium Low Low Low.Med Low Medium Low.Med V.Low V.Low V.Low V.Low V.Low V.Low V.Low Low Low Low Low Low.med Medium Medium Med.High Med.High Medium Med.High Med.High High High Medium Med.High Medium Med.High Medium Medium Trinh Xuan Manh MSc Thesis (and) Rules Inflows (and) V.Low V.Low V.Low V.Low V.Low V.Low V.Low V.Low V.Low V.Low V.low Low Low V.Low V.Low V.Low V.Low V.Low Low Low Low Low Low Med.High Med.High Med.High Medium Med.High medium Med.High Very.High Very.High Medium Medium Med.High Low Low Very.High Very.High Medium Medium Demands Low low low Low V.Low V.Low Very.High V.High Low Medium Medium V.Low Low Low.Med Medium High Low V.Low Low Medium Medium Medium Medium High High High High High High High High High Very.High Very.High High Very.High Very.High Very.High Very.High High Very.High (Then) Releases Low Low Low.Med Medium Low V.Low Low.med Med.High V.Low Low.Med Medium Low Low Medium Low High Low V.Low Low Low.Med Medium Medium Low.Med Med.High High High High High High High High High V.V.High V.V.High V.V.High V.V.High V.V.High V.V.High V.V.High V.V.High V.V.High xvii No 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 If If If If If If If If If If If If If If If If If If If If If If If If If If If If If If If If If If If If If If If If If If If Res.levels Medium Medium Med.High Med.High Med.High Med.High Medium Medium Med.High Med.High High High Medium Medium Med.High Med.High Med.High Medium Medium Medium Medium Medium Med.High Medium Med.High Med.High High Med.High high Med.High High Med.High Med.High Med.High Med.High High High High High Med.High High Medium Medium Trinh Xuan Manh MSc Thesis (and) Inflows High High Medium Medium High High Low Low Low Low Low Low Low Low Low Low Low Low V.Low V.Low V.Low V.Low Low Low Low Low Low Low Low V.low V.low V.low V.low Low Low V.low V.low Low Low V.low V.low V.low V.low Rules (and) Demands High Very.High High Very.High High Very.High High Very.High High Very.High High Very.High Medium Medium Medium Medium High high Low Low Medium Medium Low Low Low Low Low Medium Medium Low Low Low Medium Low Medium Low Medium Low Medium Medium Medium Medium Medium (Then) Releases High V.V.High V.V.High V.V.High V.V.High V.V.High High High High High V.V.High V.V.High Medium Med.high medium Med.high Med.High High Low.Med Med Med Low.Med Low Low Low Medium Medium Medium Medium Low.med Low.med Low Low Low Low Low Low Low Low Medium Medium Medium Med.high xviii No 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 If If If If If If If If If If If If If If If If If If If If If If If If If If If If If If If If If If If If If If If If If If If Res.levels Medium Medium Medium Medium Med.High Med.High Med.High Med.High Med.High Med.High Low.med Low Low.med Low Low Low.med Low.med V.Low V.Low V.Low Low V.Low V.Low Low Low Low Low.Med Low.Med Low V.Low V.Low Low Low Low Low Low.med Low.med Low.med Low.med Medium Medium Medium Medium Trinh Xuan Manh MSc Thesis (and) Rules Inflows (and) V.low V.low Low Low V.low V.low V.low V.low Low Low v.low V.low V.low V.low V.low v.low V.low V.low V.low V.low V.low Low Low Low Low V.low V.low V.low V.low V.low V.low V.low M.low Med.high Med.high Med.high High Med.high High Med.high High Med.high High Demands High High Medium Medium Medium Medium High High Medium Medium Medium High High Low Low Low Low V.low Low Low Low High High High High High High V.high V.high Low Medium Low Medium V.low Low High High High High High High High High (Then) Releases Med.high Medium Medium Med.high Medium Med.high Med.high Medium Medium Med.high Med.high Med.high Med.high Low Low.med Low Low.med Low.med Low.med Medium Medium Med.high High Med.high High High High High High V.low V.low V.low V.low Low.med Low.med Med.high Med.high High High Med.high Med.high High High xix No 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 If If If If If If If If If If If If If If If If If If If If If If If If If If If If If If Res.levels Med.High Med.High Medium Medium Medium Medium Medium High High High High High Medium Medium High High Medium Medium High High Medium Medium Med.High Med.High medium Med.high Low.med Low.med Medium Medium Trinh Xuan Manh MSc Thesis (and) Rules Inflows (and) High High High Medium Medium Med.high Med.high High Medium Medium Med.high Med.high Medium Medium Medium Medium Low Low Low Low V.low V.low V.low V.low V.low V.low V.low Low V.low Low Demands High V.high V.high High V.high High V.high V.high High V.high High V.high High V.high High V.high High V.high High V.high High V.high High V.high High High High High High High (Then) Releases high High High High High High High High High High High High V.v.high V.v.high V.v.high V.v.high V.v.high V.v.high V.v.high V.v.high V.v.high V.v.high V.v.high V.v.high Med.high Med.high High High High High xx Appendix 6: Existing operation rule curve of the Cua Dat Reservoir Table A-10: Operation curves of the Cua Dat Reservoir Periods 30/VI Crumble curve 97 Limited curve 73 31/VII 100 82 31/VIII 104 85 30/IX 109 96 31/X 110 105 30/XI 112 106 31/XII 112 106 31/I 112 103 28/II 108 97 31/III 105 90 30/IV 103 83 31/V 99 77 30/VI 97 73 Dam elevation 121.30 m 120 E Flood control Max Water level=119,05m D Flood control level=112,00m increment level=110,00m 110 C C 100 B 90 B A 80 Dead storage level=73m 70 1/7 1/8 1/9 1/10 1/11 1/12 1/1 1/2 1/3 1/4 1/5 1/6 1/7 Figure A-17: The map of operation curves of the Cua Dat Reservoir Trinh Xuan Manh MSc Thesis ... optimum water supply of reservoir for the water demands in the dry season is needed This study presents the initial research on applying Fuzzy Logic Algorithm for optimal operation of water supply in. . .Optimal reservoir operation for water supply in dry season: the case study of Cua Dat Reservoir in the Chu – Ma river system Thanh Hoa province Master of science thesis By Trinh Xuan... industry, domestic and environment However, in dry season the increasing water demand of water users is one of the important problems within water shortage in this river basin due to less rainfall