MANAGEMENT OF GROUNDWATER RESOURCES IN THE LUSAKA AQUIFER

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MANAGEMENT OF GROUNDWATER RESOURCES IN THE LUSAKA
AQUIFER
Presented at the Inaugural Meeting on
the Assessment of Pollution status
Vulnerability of water supply Aquifers of African
Cities, Nairobi, 11-13 March 2003
Daniel C.W. Nkhuwa, PhD
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INTRODUCTION
Groundwater resources becoming increasingly
susceptible to

• quality degradation, and

• quantity depletion

CAUSE
various forms of human activities generated by a
rapidly growing population.
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PRESENTATION OUTLINE

• Nature of bedrock underlying the city

• Exploitation of Groundwater

• Increased use of the ground to dispose of
  various forms of wastes

• Current indications of Groundwater Quality

• Conclusion

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Nature of bedrock underlying the city
Schists
Quartzites
Marbles
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Solution Features in Marbles
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Solution Features in Marbles (contd)
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Solution Features in Marbles (contd)
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Solution Features in Marbles (contd)
Subterranean channels
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These Features have transformed marbles into a
favourable and comparatively cheap source of
water supply to the city
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EXPLOITATION OF GROUNDWATER

• Population Growth

200 litres per capita consumption per day
? 400,000 m3 per day
Official supply only 200,000 m3 per day
? Unregulated drilling of boreholes and excessive
abstraction of groundwater from the aquifer
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Leopards Hill Rd
Shaft 5
Consequently,
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• Most of the poor communities are likely to lose
  their sources of supply as some of their wells
  are likely to dry-out.

• Cost of pumping may increase to such levels that
  the poor may not readily afford water charges.

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DISPOSAL OF WASTE
Liquid
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The 55 serviced by pit latrines - live in
high-density residential townships that generally
developed in close proximity to springs.
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Location of Peri-urban areas in Lusaka
High-density residential townships
Location is in areas where the water table is
very high.
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Water table conditions in some Peri-urban areas
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Sanitary conditions in some Peri-urban areas
Pit latrine
Shallow water table
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Disposal of SOLID WASTE
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CURRENT INDICATIONS OF GROUNDWATER QUALITY
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Concluding Remarks

• Current trends of human activities in Lusaka,
  e.g.,
• The uncontrolled settlement patterns
• Methods of waste Disposal
• Unrestrained abstraction of groundwater
• point to a resource that may have been
  inefficiently and unsustainably managed.

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Concluding Remarks (contd.)

• q Formulation of a city-wide strategy for
  enhanced aquifer-management to deal with
  pollution problems of aquifer over-abstraction
• Development of early warning and monitoring
  systems for the aquifers
• Initiation promotion of community-based
  aquifer management system with special focus on
  water supply and sanitation in a selected area

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ASANTE SANA MABWANA NA MABIBI
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