Zambia

MANAGEMENT OF GROUNDWATER RESOURCES IN THE LUSAKA AQUIFER: 

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

INTRODUCTION: 

INTRODUCTION various forms of human activities generated by a rapidly growing population. Groundwater resources becoming increasingly susceptible to: quality degradation, and quantity depletion CAUSE:

PRESENTATION OUTLINE: 

PRESENTATION OUTLINE Nature of bedrock underlying the city Exploitation of Groundwater Current indications of Groundwater Quality Conclusion Increased use of the ground to dispose of various forms of wastes

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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  Unregulated drilling of boreholes and excessive abstraction of groundwater from the aquifer Official supply only 200,000 m3 per day

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Consequently, Shaft 5 Leopards Hill Rd

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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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Shallow water table Pit latrine Sanitary conditions in some Peri-urban areas

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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 andamp; problems of aquifer over-abstraction Development of early warning and monitoring systems for the aquifers Initiation andamp; 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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