1. ASSESSEMENT OF GROUNDWATER VULNERABILITY IN YANGON CITY, MYANMA Dr. Wint Wint Htun Assistant Lecturer, Department of Geology University of Yangon 29th January, 2015 2. YCDC Area Yangon Division Panhlaing River Hlaing River Yangon Yangon River Union of Myanmar 3. YANGON between URBAN PLANNING HISTORY OF YANG 1960s & 1980s 1920 - 8625 Ha 1974 - 20862 Ha 1985 - 34613 Ha It had expanded gradually in N-S direction in 1960s and 1980s Source: Hlaing Maw Oo, 2007 4. URBAN PLANNING HISTORY OF YANGON rapidly in E-W direction . developing new suburbs in 1990s through the present time. in an attempt to balance the elongated south to north growth of the city limits, development of new towns in the east and west TOWN EXTENSION (Site & Services Scheme) INDUSTRIAL ZONES Source: Hlaing Maw Oo, 2007 5. Types of water resources in Yangon area Ngamoeyeik Gyophyu 1.Surface water Reservoirs Gyobyu (started from 1940) Hlawga (started from 1906) Phugyi (started from 1992) Ngamoeyeik (started from 2007) Lakes and ponds Kandawgyi Lake (1879-1906) Innya Lake (1884-1906) Lakes and ponds 2.Ground water Open wells (hand-dug wells) Tube wells 30 wells (1842) YCDC tube-wells Ngamoeyeik Reservoir Gyobyu Reservoir Phugyi Pyugyi Reservoir Hlawga Hlaw ga Reservoir Bago River Twantay Canal Yangon River Lagunpyin Reservoir Bago River 6. Monthly Temperature and Monthly Rainfall Monthly mean temperature is essential in water usage Water demand in township is mainly depend upon variation of temperature 7. Gyophyu Reservoir (correlation between water level and total rainfall) 3000 2500 2000 1500 1000 500 0 1985 1988 1991 1994 1997 Year Hlawgar Resevoir (correlation between lake water level and total rainfall) 800 700 600 minimum maximum total rainfall 2000 2003 2006 Phyugyi reservoir correlation between water level and total rainfall 1600 1400 1200 500 400 300 200 100 0 Year minimum maximum total rainfall 1000 minimum 800 maximum 600 400 total rainfall 200 0 Year Correlation of water level and total rainfall 8. Water supply in Yangon area (2010) Water resources Surface water (reservoirs) Gyobyu 27 MGD Phugyi 44 MGD Hlawga 14 MGD Ngamoeyeik 90 MGD Ground water About 400 tube wells over 20 MGD Lakes and ponds Total over 195 MGD (Million gallon per day) 9. Depending on total population and served population data analysis every townships show the lack of water sufficiency. Half of total population of Bahan, Botahtaung, Dagon, Kyauktada, Lanmadaw, Latha, Mingalartaungnyunt, North Okkalapa, Pabedan, Pazundaung, and Tarmwe have access to YCDC water supply. Ahlone, Hlaing, Hlaingtharyar, Insein, Kamaryut, Kyeemyintdaing, Mayangone, Mingalardon, North Okkalap, Sanchaung, South Okkalapa and Thaketa get only small amount of or limited water supply. 10. Drinking water lake in Yangon Area 100 90 80 70 60 50 40 30 20 10 0 Township Name drinking water lake fire control 11. The domestic water consumption per month is increased in Ahlone, Tarmwe, Yankin, Bahan and Pabedan Townships. Utilization for commercial purposes in Insein is increased more than the other townships. Departmental water consumption per month is found to be high in Dagon, Mayangone, Yankin and Insein. 12. As population density increases, an ever-increasing demand on water resources and an ever increasing complexity of management issues are created. Urban expansion coupled with population growth accelerated the deterioration of 13 environment and degradation of quality of groundwater. 13. Location of Industrial zones Industrial zones Proposed industrial zones 14 14. YCDCs tube-wells in Townships 35 30 25 20 well no. 15 10 10 5 0 33 14 9 5 2 2 23 10 5 16 13 6 26 11 1 23 17 9 8 9 4 Tube-well located at 13thstreet, lanmadaw township 3 3 2 Tube-well located at in front of the railway station, kyauktada township 15. Water wells in townships (1996-2008) Gp 1 South Okkala and North Okkala 60 50 40 30 20 10 0 Gp 3 Hlaing, Kyimyintdaing and Mayangone (west)50.5 Gp 2 Dagon, Mayangon, Mingalardon, Yankin, Kamaryut and Sanchaung 250 200 150 100 50 0 Gp 4 - North Dagon 200 190 174 1 54 161 150 145 50 50 49.5 49 48.5 48 47.5 47 100 50 24 0 33 137 140 76 40 16. Water wells in townships (1996-2008) Gp 5 - Shwepyitharyar 90 180 80 79 160 Gp 6 - Hlaingtharyar 168 170 151 154 70 60 50 40 30 20 10 0 57 140 120 100 80 79 84 60 40 20 0 144 131 Gp 7 Ahone, botatung, Pazundaung and Mingalartaungnyunt 30 25 20 15 10 5 6 6 0 25 21 17 11 17. Built up area occupied many areas of water resources especially lakes and ponds 18. Water BudgetSq km 400 350 Urban growth and land area reduction Subsurface flow cu.m/year 800000000 700000000 600000000 500000000 400000000 300000000 200000000 100000000 0 1920 1974 1985 Subsurface flow cu.m/year 300 250 200 Area Town 150 Land area 100 50 0 1920 1974 1985 Year Total land area = 480 sq.km Area sq ft Land Subsurface flow Year (Town) area ( recharge) 1920 86.25 393.75 759738839.6 1974 208.62 271.38 523626479.5 1985 346.13 133.87 258301558 19. Potential sources of groundwater contamination Increase in households through population growth, economic activities and lifestyle changes directly transform the condition of the water resources. Controlling factors for the deterioration of water resources are interaction ofclimate, topography and drainage system, geology, population density and land-use. 20. Geology Geological Map of Yangon City (Win Naing, 1972) 21. Hydrogeology Aquifer (Rock) Upper Pegu Group (Thadugan Sandstone, Hlawga Shale, Besapat Alternations) - Limited in Thadugan sandstone Irrawaddy Formation (Arzanigone Sandrock, Danyingone Clay) Mainly Arzanigone sandrock Aquifer (Alluvium) Valley-filled deposit - Important aquifer in the western part of the study area Younger alluvium - Widely distributed 22. Well locations in different lithology I - valley-filled deposit ( good water quality) II- Arzanigone sandrock ( good water quality) III- Danyingone clay IV - Younger Alluvial deposit V - Thadugan sandstone V IV I III II 23. Types of aquifer depth (feet) soil types Types of aquifer depth (feet) soil types Arzanigone sandrocks 90-110 sand Valley-fill deposits 125-157 coarse sand and gravel 80-137 sand 118-170 fine gray 170-200 sand 114-147 clay sand and gravel 82-129 145-170 fine sand /134-145 coarse sand and gravel 70-100 sand 206-290 sand and gravel 420-480 sand blue 104-170 sand and gravel 213-243 460-490 fine to medium sand /253-273 coarse sand and gravel Danyingone clays 130-264 coarse sand and gravel 90-118/139-164 sand and gravel 334-385 gray sand 130-160 sand and gravel blue clay and coarse 185-210 sand 140-180 sand and gravel medium sand and 105-130 sand and gravel 110-130 yellow 110-140 medium sand Alluvial 126-156 Sand 295-335 medium sand 274-364 gravel and sand gravel 480-510 sand blue 151-221 coarse sand and gravel 247-280 coarse sand and gravel 101-127 sand and gravel 223-261 coarse sand and gravel 105-125 sand with fine gravel 370-390 medium sand and blue 100-130 sand fine and yellow medium sand and 430-470 fine sand 335-365 gritty 40-60 sand and gravel 600-630 sand and gravel medium sand and 100-148 gravel 570-590 sand and gravel 200-295 sand yellow and gravel 520-580 sand 325-350 medium sand blue 320-400 medium sand blue 24. Assessment of groundwater vulnerability Groundwater specific yield map and its wells locations Depending upon this map, the specific yield is abundant in the south-west and western part of this study area. 25. Water quality Unbalance between discharge and recharge may cause groundwater quality degradation Over-exploitation can also disturb the saltwater and fresh water interface, leading to local or regional saline contamination 26. TDS distribution (Total Dissolved Solid) Excellent less than 300 mg/litre Goodbetween 300 and 600 mg/litre Fairbetween 600 and 900 mg/litre Poorbetween 900 and 1200 mg/litre Unacceptable greater than 1200 mg/litre Over pumping of groundwater will cause the intrusion of saline water to the well in the area to the tidal river and chaung. 27. Chloride distribution Chloride originates from natural sources, sewage and industrial effluents, and saline intrusion. Guideline value of Chloride is 250 mg/litre This presentation reveals the quality of groundwater in terms of Total Dissolved Solid (TDS) and Chloride (Cl) 28. Drainage Coverage Map of the Study Area Yangon-Mingaladon Ridge is main watershed for Hlaing River and Ngamoeyeik Creek 29. Contour map showing potentiometric level Topography normally controls the subsurface water flow. However, permanent reservoirs like Innya and Kandawgyi can feed water into the local aquifers continuously (modified after Win Naing and Maung Maung1996) 30. Land use map modified by Wint Wint Htun 31 31. Figure showing Industrial zones, solid waste disposal sites and groundwater flow direction Old solid waste disposal site Existing solid waste disposal site Industrial zones Proposed industrial zones 32 32. Main solid waste disposal sites And industrial zones Waste disposal sites are located at the area of shallow water-table aquifers situated at the depth of 40 ft below the surface. 33. Low lying areas are high vulnerable to flooding during rainy season. But the southern city may have further problems. Flooding 34. All 22 drainage channels present in ngon are polluted. Channel water pollution is rather high in dry season when the surf n-off by rain water is absent. Channels passing through the densely populated area a hly polluted and they will contaminated the groundwater lying below. 35. Groundwater vulnerability assessment Aquifer vulnerability index (AVI) The Vulnerability Index is one of the methods simplest, fast and easy to quantify the vulnerability, since so single it uses the hydraulic conductivity and the thickness of the layers of different material that are on the level of the water. c=bi / Ki for the layers i = 1, 2, 3,...,i where: bi: it is the thickness of each layer of the ground water, Ki: it is the hydraulic conductivity of each layer, and c: it is total the hydraulic resistance by ft of depth (inverse of Ki, [ time]), 36. Groundwater vulnerability assessment map and its wells locations Groundwater vulnerability index map by using AVI (aquifer vulnerability index) method for reconnaissance studies. 37. Insein iver Ngamoeyeik Stream The area of very high vulnerability include someparts Inya Lake ngRiver Kandawgyi Lake Dagon of Latha (Alluvial), Dagon (Valley-fill deposits), and Insein (Danyingone Clays) Yangon River Scale 0 5 10 Km 38. Groundwater management tools TECHNICAL 0 1 2 TOOLS Resource Basic Conceptual Models linked to Assessment knowledge model based on decision-support of aquifer field data and used for planning and management 39. Management Process Capacity Capacity Demand Resources: Surface and subsurface water Factor of safety Interaction with the environment Demand Water utilization: urbanization and industrial development 40. Water shortage (4-5-2008) After Nargis 41. Challenge in groundwater use 42. Thank you very much for Your kind Attention