Dhaka, Bangladesh
Vulnerability and sustainability of the Dhaka
groundwater resource
William Burgess, Kamrul Hasan, Emma Rihani, Mohammad Hoque
Kazi Matin Ahmed, Dhaka University
George Darling, BGS
Dhaka, Bangladesh
Vulnerability and sustainability of the Dhaka
groundwater resource
15 million inhabitants
85% water demand supplied from groundwater
250 DWASA boreholes distributed throughout the city
DWASA Pumping >300 Ml/d
Unregulated peri-urban slum hand-pumped tubewells
Unsustainable abstraction
- declining water levels, 1 m/year
- vulnerable to quality deterioration
from induced river recharge rather than
urban sources of contamination
NASA
Chadnighat river water treatment works
1874
DPHE borehole
1949
Dhaka WASA established
1963
Bangladesh independence
1971
220 water supply boreholes, Dhaka aquifer 1990s
The Chadnighat water works: 5% of water supply to Dhaka
23.6800
1999
90.3400
90.3900
90.4400
Longitude
90.4900
23.7300
23.7800
Latitude
23.8300
23.8800
SW
NE
Induced
recharge
through
R.Buriganga
DHAKA METROPOLITAN AREA
Bashabo
Holocene
sands
Madhupur
Clay
Dupi Tila Pliocene sand aquifer
Dhaka: Municipal waste disposal in flooded depression
Dhaka: Municipal waste disposal in flooded depression
Tannery solvents: PCE, TCE
Dhaka: unregulated industry, contaminated land
and effluents
Industrial effluent + raw sewage draining to River Buriganga
Low quality water invades the
aquifer in the south:
23.7800
as vertical seepage from industrial
areas ?
23.7300
or from the polluted River
Buriganga?
23.6800
Latitude
23.8300
23.8800
Dhaka:
groundwater EC,
1999
1999
90.3400
90.3900
90.4400
Longitude
90.4900
23.6800
1999
90.3400
90.3900
90.4400
Longitude
90.4900
23.7300
23.7800
Latitude
23.8300
23.8800
-20
Baseline
groundwater
away from
Dhaka
-30
W Works
tubewell
2
 H‰
-25
-35
JN Coll.
tubewell
-40
-45
-7
-6
-5
 O‰
18
-4
-3
The vulnerability of the Dhaka DWASA aquifer
• Groundwater quality variation
demonstrates aquifer vulnerability
• Induced river recharge
pollutes aquifer in SW Dhaka
• Abstraction boreholes
protect central urban area
• Organic contamination identified
from industrial zones?
• Urban recharge a longer term threat
Shallow groundwater – vulnerable hand-pumped
supplies
The vulnerability of the Dupi Tila aquifer of Dhaka
Recommendations
Monitor
groundwater levels, groundwater quality
surface water quality, industrial discharges
city wide
shallow-deep
+DWASA boreholes
Environmental legislation
prioritise industrial discharges & river quality
The future
extend distributed supplies, centralise treatment
protect urban groundwater as a strategic resource
develop peri-urban well-fields+treatment plants
The London Basin aquifer – over-abstraction, and water level rebound
The London Basin aquifer – over-abstraction, and water level rebound
Groundwater dependent megacities
for individual cities see http://www.iahorg/commwg.htm
New York, Los Angeles, Mexico
City, Lima, Santiago, Buenos
Aires, Rio de Janeiro, Sao Paolo,
Bogota, Tokyo, Osaka, Hong Kong,
Manilla, Jakarta, Beijing, Bombay,
Madra, Bangalore, Hydrabad, Dhaka,
Karachi, Lahore, Delhi, Tehran,
Cairo,… (London, Birmingham,
Liverpool, Nottingham …)
Dhaka, Bangladesh
Vulnerability and sustainability of the Dhaka
groundwater resource
William Burgess, Kamrul Hasan, Emma Rihani, Mohammad Hoque
Kazimatin Ahmed, Dhaka University
and George Darling, BGS
Geological map of Bangladesh
Water sources for urban populations: the options
• Local surface water
London
• Imported surface water
Manchester
Calcutta
• Treated foul water
Windhoek
• Desalinated water
Dubai
• Groundwater
→ local
→ imported
Dhaka
Sanaa
Groundwater – cheaper to develop, in stages,
generally good quality, less vulnerable, less treatment
Vulnerability of urban groundwater
Over abstraction → declining water levels
declining efficiency
increasing costs
shallow aquifer dewatering
modified recharge
Contamination →
unsewered sanitation
landfills
industrial discharges
contaminated land
contaminated surface water
saline water