1. The project delivery specialists Modelling of Sedawgyi Irrigation Network with RIBASIM Internship assignment Sebastiaan Quirijns 1

2. Welcome Thank you all for contributing to my study, by sharing all of your resources 2

3. Contents Introductions Goal of project Scope of project RIBASIM Background RIBASIM Requirements Initial Analyses Scenarios Results Conclusions and Recommendations Q & A End 3 Scenarios - Base Case - Do Nothing Case - ADB Reference Case - Sustainable Urban Drainage System - Irrigation Efficiency (CTA) - Secondary Open Channel - Separation of Water Resources System

4. Introductions Introduction speaker: Netherlands Delft Technical University of Delft Hydraulic Engineering Graduating in July 2015 Internship for Peter Kerssens of Haarlem Hydraulics 4

5. Introductions Current issues of the Sedawgyi Irrigation Network No clear distinction of the main function of the Sedawgyi dam Too high shortage of water for irrigational purposes Too much water which is spilled during rainy season The main goal of the study is: “Modelling of the water resources in the Mandalay Region in order to increase the water usage efficiency” 5

6. Introductions Scope of the study Four natural boundary limits North Sedawgyi reservoir East Shan Hills South Dokhthawaddy West Ayeyarwaddy RIBASIM applications Modelling of water resources for rivers and basins Depth of study Mandalay is simplified into two subjects Public Water Supply Moat flow Sedawgyi Dam controls inflow into basin No groundwater flow included in the model 6

7. Introductions Four natural boundary limits North Sedawgyi reservoir and mountains East Shan Hills South Dokhthawaddy West Ayeyarwaddy 7

8. RIBASIM Background RIBASIM (RIver BAsin SImulation Model) Generic model package for analysing the behaviour of river basins under various hydrological conditions, developed by Deltares (the Netherlands) Simulation of water allocation in a water resources model Main classification of the nodes are Demand, Control and Layout. Time step size is daily, weekly, half monthly or monthly basis Demand nodes determine flow in the links Basin performances Water allocation Water shortages River basin water volumes Flow composition Crop production Flood control Water supply reliability Etc. 8

9. RIBASIM Background Important aspects for Agriculture in RIBASIM irrigation water distribution topography and lay-out of the irrigation area crop and soil characteristics crop plan expected and actual rainfall reference evapotranspiration agriculture practice operation and irrigation water management actual field water balance crop survival fraction potential crop yield and production costs 9

10. RIBASIM Background Typical applications long term basin planning - time horizon of 20 to 25 yrs. short term water allocation- time horizon 0,5 to 1 yrs. scheduling In season operation- during the season based on the scheduling actual situation in the field flow forecasting system- any time at various locations 10

11. RIBASIM Requirements Primary data required for modelling with RIBASIM Time series Rainfall Five locations Dependable rainfall Five locations Water balance of Sedawgyi reservoir Inflow Evaporation Reference evapotranspiration Fixed data Catchment areas Reservoir volume Cultivated areas Crop data 11

12. Initial Analyses Sedawgyi Irrigation Network Map Sedawgyi Reservoir Mandalay (±1,2 million inhabitants in 2014) Madaya (±30000 inhabitants in 2014) Three rivers and/or canals connected to Sedaw Weir Mandalay Main canal Yenatha canal Chaungmagyi Many agriculture Many distributaries 12

13. Initial Analyses Non Revenue Water Mandalay 63% Physical losses Leakages Overflow Commercial losses Under counting Illegal connections Unbilled consumption Mandalay’s demand 101 l/capita/day 15 % supplied by surface water 15 l/capita/day Note: Mandalay does not get water from Sedawgyi Water Resources System. It is assumed this way, because of modelling’s sake. 13 Saying in modelling “ Prove from the absurd”

14. Initial Analyses IndexDY’s Length [m] Depth [m] Q [m 3 /s] Summer paddy [ha] 1 Shwetha- Chaung3810,01.056,65608,4 2Thamok-So10363,21,454,11827,6 3Nandar5852,21,134.01633,2 4Alebon6370,30,929,21594,4 5Htanpingon6446,50,922,41276,8 14 5 Largest cultivated areas (of total 20) connected by distributaries (DY’s) to the Mandalay Main canal

15. Initial Analyses Agriculture in Sedawgyi Irrigation Network CropsTotal Area [ha]percentage Summer Paddy2988364% Winter Paddy2988364% Sesame5931% Sunflower00% Pulses32367% Corn29296% Ground nut4461% Garlic00% Wheat40599% Soybean2290% Banana36558% Sugarcane 527911% Vegetables2861% Cattle6841% Total46939100% 15

16. Initial Analyses 16 Primary canals Mandalay Main Canal Yenatha Chaungmagyi Secondary canals All DY’s

17. Initial Analyses Climate Change effects Forecasted changes at Mandalay (Dry Zone) Slight increase of Annual Rainfall (10% in 2040) More drought in the pre- and post-monsoon periods (May, June & October: 35% lower rainfall) Decrease in monsoon duration Increase in intensity of rainfall (25%) during monsoon period 17

18. Initial Analyses SeasonPeriod Average temperature (°C) Expected increase in temperature in 2020 (°C) Average temperature in 2040 (°C) Change in periods Climate change factor for rainfall Winter November to February 16 to 30 +1.2+2.2 October to februari 98.35% SummerMarch to April21.5 to 37+1.0+2 March to June 98.35% MonsoonMay to October25 to 34+0.6+1.6 July to September 100.37% 18 Climate Change effects

19. Initial Analyses Sedawgyi Dam key values Length of dam 1256 m Top of dam 131,4 m Max water level 130 m Full Reservoir level 128 m Dead capacity level 111 m Catchment area 342500 ha Hydropower cap. 25 MW 19

20. Initial Analyses Water spread/Capacity curve for the Sedawgyi Reservoir 20

21. Scenarios The scenarios for long term modelling have to be included with some effects: Long term effects Population growth of Mandalay to 2,3 million Urbanization of Mandalay Increase in paved open areas Madaya is connected to Sedawgyi Resources System Climate Change 21

22. Scenarios Design Criteria Hard design criteria  Direct results, easily measurable Reservoir volume Reservoir spillage Net flow in and out of reservoir Generation of hydropower Actual cultivation areas Supply/demand ratios for cultivations Irrigation efficiency Supply/shortage for PWS Continuous flow in the moat canal Soft Design Criteria  Indirect results, difficult to measure Quality of life, food security, food diversification, environment, ‘Green cities’, sustainable development, etc… 22

23. Scenarios 23 Base Case 2013-2014 Main function of the ‘Base Case’ is to visualize the current situation Second function is for calibration of the model

24. Scenarios Do Nothing Case 2039-2040 Effects long term effects are included Main goal visualize issues Ideology see what happens, autonomous developments (population, urbanization, CC), but no corrective measures (yet) 24

25. Scenarios ADB Reference Case 2039-2040 Effects Network Coverage is increased to 95% (2,2 million people) Surface water dependency is increased to 47% (68 liter/capita/day) NRW is reduced to 10% Main goal Increase welfare in Mandalay Increasing demand of Mandalay Reduce losses Ideology Since most of these plans have a large probability of being executed. This case serves as reference case. 25

26. Scenarios Sustainable Urban Drainage Systems 2039-2040 (SUDS) Effects Increasing soil permeability→runoff via groundwater → return flow to the surface water ADB reference plan Main goal Reduce flooding in the city Beautification of Mandalay Ideology By achieving the main goals the ‘Qualitiy of life’ will increase in Mandalay 26

27. Scenarios Irrigation Efficiency 2039-2040 (via Capacity Training Agriculture) Effects Increasing field irrigation Efficiency to 90% ADB Reference Plan Main goals Increase yields/production Save water higher supply/demand ratios for Agriculture Ideology If the efficiency of irrigation is increased, by supplying new technology and training, this will lead to an high effective supply, and result in more water available for PWS purposes. 27

28. Scenarios Secondary Open Channel 2039-2040 (SOC) Effects A collector drain is connected to Mandalay Main Canal Flood flow from Shan Hills is redirected and redistributed in the Southern Irrigation Network System ADB Reference Plan Main goals Increase safety of Mandalay More efficient use of flood flow Ideology If the the water from the flood flow is redisitributed, this should lead to a lower demand to Sedawgyi in the southern area. Thus an increase in supply in the northern area. 28

29. Scenarios 29 Catchment area: Detailed Catchment area: Simplified

30. Scenarios Separation of Water Resources System 2039-2040 (SWRS) Effects Removing Mandalay Nodes for PWS and Moat ADB Reference Plan Main goal Increased water availability for irrigation purposes and PWS of Madaya Ideology Mandalay’s water supply will come from any other sources, except Sedawgyi Water Resource System 30

31. Results 31

32. Results 32

33. Results 33

34. Results 34

35. Results 35

36. Results 36

37. Results 37

38. Results 38

39. Results BCDNCADBSUDSCTASOCSWRS Gross Supply [Mcm]13437,742476,942073,742364,23796743351,845665,7 Effective Supply [Mcm]5662,113932,61776517897,42894318313,719321,3 Overall Irrigation efficiency42,142,2 76,242,242,3 39 Irrigation Efficiency per scenario in 2013-2014 and 2039-2040

40. Results 40

41. Results 41

42. Results 42

43. Conclusions & Recommendations The increased dependency of surface water from the Sedawgyi for PWS in Mandalay is very unlikely to occur in practical sense, since the Ayeyarwaddy and groundwater are the major sources for water supply. Nevertheless, the cases have been modelled this way, because it is always a good modelling incentive to prove from the absurd/extreme values in order to show the differences between the scenarios the best. The model shows clearly, given the current operational settings of the Sedawgyi dam, that in 2040 as a result of the expected population growth and increased urbanization, large water shortages. Solely the Sedawgyi Reservoir can not supply both, public water supply and irrigation, if no additional corrective measures are taken (do-nothing scenario) The effect of the water supply situation will be exacerbated by the expected climate change effects in 2040. Sustainable Urban Drainage Systems (SUDS) are strongly recommended to improve urban drainage and flood management in and around Mandalay city, but will have a relative small effect on the water resources /water supply conditions. 43

44. Conclusions & Recommendations One of the most effective measures to improve the situation is to increase the irrigation efficiency, reducing losses in the system and ensuring that irrigation water will be delivered at the right moment and the right place. A collector drain at the Shan plateau foothills is strongly recommended as it will be effective to reduce the flooding problem in Mandalay city, but will not do much for the water supply situation. Separation of the Water Resources System of Mandalay and Sedawgyi is very effective for increasing the cultivation areas and ensuring the city water supply. These cultivations react correspondingly by having an acceptable supply demand ratio, if compared to the other cases. In some cases the North-Eastern parts of town (and people) get flooded due to reservoir releases from Sedawgyi dam. This generally happens without any warning, and in winter time when water levels are high already. Rescue service is provided by the government, but it would be better to provide flood early warning. Further emergency assistance is given by Red Cross and other NGOs. 44

45. Conclusions & Recommendations Final Conclusion Given the current operational settings of the Sedawgyi Dam, it clearly shows that in 2040 Sedawgyi Reservoir could not support both Public Water Supply and irrigation systems. So the water resources systems of Mandalay and Sedawgyi Irrigation Network should be separated. Sedawgyi will supply the irrigation and Mandalay will be provided by surface water of the Ayeyarwaddy and Dokhthawaddy. The modelling results of this study support the choices made by ADB PPTA. If the irrigation efficiency is increased (ie. In steps of 50% to 60% to... to 90%) in the long term (20 to 25 yrs) high yields can be achieved, by investments in training, technology and resources. This will also include lower losses and spillages in the water resources systems. The current allocation of the dam is not efficient, in a way that there is still a high shortage of water supply in the downstream area of the Sedawgyi. In the future the allocation of Sedawgyi Dam should be based upon a hydrological study and including the demands of all stakeholders. 45

46. Questions and Answers Any Questions?? 46

47. Final Thank you for this amazing experience here in Myanmar 47