OVEREXPLOITATION OF GROUNDWATER AND

CONSEQUENCE IN GREATER YANGON (Myanmar)

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Speaker : Daw Than Than Soe (*) Email: thanthansoe.sch@gmail.com

Greater Yangon 4 Districts 34 Townships Population 5.2 million (Census /2014) Métropolitain (City Area) 10,170 km2 (3930 Sq mi)

Writer : U Myint thein(**) Email: myint.thein.geo@gmail.com

GEOLOGY AND HYDROGEOLOGY (GREATER YANGON)

1 Alluvial deposit (gravel, sand, silt, clay and laterite)

2. Valley Filled Deposit (the older alluvium of terrace of gravels, sands and silts)

3. Ayeyarwady Formation (the non-marine fluvial sediments) (Arzanigon Sand-rock, Sand, gravel and Danyingon Clay)

4. Upper Pegu Group (Thadugan Sandstone, Hlawga Shale, Besapat Alternations)

NOTE: The rock type in Greater Yangon is mainly soft rock

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GEOLOGY HYDROGEOLOGY 1. Alluvial aquifer : unconfined Thickness :20m ~ 75m (50 ~250ft) (Approximate) Yield (45 – 2200)m3/day 2. Valley Filled Aquifer: Thickness: 35 ~ 90 meter (120 to

300 feet), (principle aquifer) Yield (1000 – 4000)m3/day 3. Irrawaddy Aquifer: Thickness: is ranging from

250meters (800 feet to more) Yield is ranging from 70m3/day to

2270m3/day Peguan Group is poor Aquifer

discharge low yield with non-potable quality

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GEOLOGICAL

MAP

OF

GREATER

YANGON

Lithological Cross-Section of Tube Wells showing the aquifers Greater Yangon

4 Source: Myint Thein and Thein Tun (Hydrogeologists), RWSD, 1993

GROUNDWATER & WELLS IN GREATER YANGON

1842 (Myanmar King Era) 30 Dug Wells 1893 to 1946 17 to 400 tube wells 31000 m3/day(8.2 MGD) From 1948 to 1986 3000 237000m3/day (calculated)628MGD After 1988 there are not drilling license fee in Yangon City 1992 YCDC discharged 20MGD (90910m3/day)

2003 (Private Wells discharged) 74MGD(280148m3/day)

2013 (YCDC – 645 Wells only) 54.52MGD (206380m3/day) 2013 Private Wells discharged 106.10MGD(401632 m3/day) 2015 Private wells discharged 198.3MGD (475000m3/day)

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Current situation: more than 100,000 tube-wells are discharging for Domestic, Industries, Agriculture and others in Greater Yangon

Estimated 45% ~ 50% of population are relying on groundwater; especially in new settle towns

CONSQUENCES

B . LAND SUBSIDENCE

A . GROUNDWATER LEVEL

C. GROUNDWATER QUALITY DETERIORATION

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OVEREXPLOITATION OF GROUNDWATER IS REAL

D. SALT WATER INTRUSION

A. GROUNDWATER LEVEL DEPLETION (Greater Yangon)

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1992 Groundwater Level was within 40 ft from ground in Yangon city 2017 Groundwater Water levels are dropping; compared with existing hydrogeological monitoring data from 1992 are nearly 100% drop, mostly in Downtowns Yangon City

B. LAND SUBSIDENCE

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MARINE CLAY (Lower Kyimyinting)

No evidence are recorded but it could be happened along riversides and soft soil area High rise buildings are huge numbers and because of structure’ load weights; weak foundation, less Geotechnical Instrumentation and groundwater monitoring

C. GROUNDWATER QUALITY DETERIORATION

• the ground water from tube wells are expected to have water quality problems, especially high concentrations of saline (Chloride), iron (Fe+2, Fe+3) and acidity (pH).

• Yangon City, Yangon River, Pegu River and Hlaing & Panhlaing River are tidal effected, located near the Andaman Sea and Bay of Bangal

• Saline intrusion is high potential, especially in southern part of Yangon City area and new settlement.

• Chloride (Cl+ ion) content is between 1,000–10,000 mg per liter somewhere in Yangon City.

• Chlorite content is above WHO Standards • High Irion content with Magnesium also

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D. SALT WATER INTRUSION

Ngwe Thein + Myint Thein (2001)

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1939 British Governor act “ The Underground Water Act” Union of Burma (Burma Act IV,1930) (21st June 1930) The original Burma Groundwater Act 1930 had its jurisdiction with Yangon

City limit; However, the act allows for extension of it jurisdiction beyond the Yangon City. It is nearly a century old and not applicable and suitable with the present changing situations

A revised draft act has been prepared in 2014 with water related agencies

and submitted to the Government Law Commission through Ministry Groundwater Acts have to cover the following sectors: Users / Driller contractors / Consultancy / Owner / Developers / Technical sectors / Environmental impact (chapter by chapter) 2016 -17 Department of Human Settlement and Housing Development ,

Ministry of Construction was submitted “New Groundwater Act “ to Parliament Hluttaw through General Attonery

GROUNDWATER ACT

JUSTIFICATION AND CONCLUSION 1. Recharge and Discharge of aquifers to maintain water level , not to get vulnerability and not to intrude Salt water / Sea water 2. Database Management & System is essential 3. Integrate with Public Health & Sanitation, Civil Environment and Geo-environment 4. Exchange of knowledge and best practices 5. Groundwater Act and Management (Administrative /Technical) are essential (Country-wide) 6. Imposition by Groundwater Act and Institution / Organization for Technical Management / Have to know Groundwater budget 7. Groundwater Law have to cover water well drilling contractors, groundwater user (domestic, towns water supply, industries) and conservation charges 8. In Yangon, There are no outstanding of Marine Clay especially in city downtown (metropolitan) area as like Bangkok wide area 9. Reference to Geotechnical Investigation reports (soil logs ) and excavation

seen but it is small area compared to township area. 10. Groundwater management is 44 years behind Thailand (Bangkok) and is 70 years behind India; It is time to act Groundwater Law

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World Water Day Myanmar 2019

Be aware of Groundwater Myanmar

Than Than Soe (*) Vice Chairman, Water & Sanitation TD, Fed. M.E.S Director (Retired), Department of Human Settlement and Housing Development, Ministry of Construction Freelance Consultant, Water & Sanitation Development Project Myint Thein (**) Groundwater & Wells Engineering Consultant (Freelance), Member of Advisory Group / National Water Resource Committee Member of Groundwater Foundation (CA, United State) Former Hydrogeologist (Rural Water Supply Division) myint.thein.geo@gmail.com

Thanks for attention