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issues and problems in the city of lusaka3.5GeneralGroundwater is a vital resource in Lusaka, particularly that alternative sources of water supply are becoming increasingly scarce. As such, it forms the basis of life and an essential pre-requisite of many socio-economic activities, development and growth. With an ever-increasing population migrating towards the city in search of a better life, the major cities of the country, particularly Lusaka, have experienced a proportionate increase in the rates of urbanisation and an upswing in unplanned settlements. This rate of population growth has overwhelmed the rate of provision of most basic and essential social services including water supplies. As a result, large numbers of people, who need water supply and sanitation services but who cannot readily get these services by self-provision, continue to exert enormous pressure on groundwater resources. This pressure has generally come in the form of:
Thus, one major problem of the limited planning capacity and the ensuing unplanned settlements in the city has been the settlement into areas that were previously considered unsuitable for habitation because of, for instance, the high water table. In this regard, most of these practices have greatly heightened possibilities of groundwater contamination. And as many of these (low- and high-income) settlements rely either on pit latrines or septic tanks to dispose of their sewage and heavily depend on groundwater sources obtained from their private sources, consumption of such water, which is usually of unfavourable quality, has undoubtedly heightened outbreaks of waterborne diseases, such as cholera and dysentery that have been experienced in many areas of the city. In most parts of the city, these outbreaks have nearly turned into a perennial problem. These outbreaks have led to:
While this has been a recurrent problem in the city, there has been no detailed study that has attempted to link these outbreaks to the quality of water. Although available morbidity and mortality figures already highlight the magnitude of the problem a perspective of annual expenditures to treat these diseases will undoubtedly show the problem from another viewpoint. 3.6Current land use practices in the cityLusaka is the largest urban area in Zambia and like any other major African city, it has distinctive land use patterns, the major ones being (Fig. 14):
 
Fig. 14: Land use map of the city of Lusaka Agriculture This is concentrated on the peripheries of the city although the most important commercial enterprises are located to the east, south-east, south, south-west and west of the city. Most of these agricultural activities are supported by lateritic soils formed by weathering of the marbles. Commerce and Industry Most of these activities are concentrated in the south-west, west and north-west of the city and mostly over karstified marbles. Residential The city of Lusaka has experienced a very rapid growth of population arising mostly from the rural-urban migration, which has been driven by the search for employment and false hopes of better livelihoods in the city. Of the city’s estimated two million inhabitants, about 75 % live in high-density areas, which are characterised by limited or absence of public services, high population density with sub-standard living conditions. The remainder of the population lives in what have been commonly referred to as medium- and low-density areas, where living standards are relatively better because of a comprehensive provision of public services. Since population growth has not kept pace with the development of infrastructure for the provision of adequate and safe methods of liquid and solid waste disposal, the city has experienced increased and indiscriminate use of the ground, which forms the water-store for the city, to dispose of different forms of waste. Arising from the various forms of human activities that have been engendered by a rapidly growing population in Lusaka, the city’s groundwater resources have become increasingly susceptible to quality degradation and quantity depletion. In some areas of the city with no reticulated water supply system, residents have resorted to obtaining water from shallow wells. In many cases, these water sources have been of insufficient quality and have thus, contributed to the recurrent outbreaks of waterborne diseases in many areas of these areas. 3.7water supply and groundwater abstractionCurrently, rapid growth of population in Lusaka has outstripped the rate of provision of this basic social goods as well as adequate sanitation services. For instance, peak water demand to cope with current requirements estimated at an average per capita consumption of about 200 litres per day stands at about 400,000 m3 per day for a population, which is estimated at two million. Measured against actual daily production of about 200,000 m3 per day currently supplied by the water authority, the deficit in supply raises conspicuous concern. The current unsatisfied water demand has triggered a process of indiscriminate borehole drilling (Fig. 15) and excessive abstractions of groundwater from the aquifer. In addition to drought-episodes, the aquifer has consequently experienced a steady and progressive decline of the water table (Fig. 16). Progressive lowering of the water table will undoubtedly increase production costs, thereby imposing restricted access of the resource to the low-income group of the city population, who may not afford to pay for the high costs of production. 
Fig. 15: The location of water supply boreholes over the Lusaka aquifer. Source:Nkhuwa, 1996 Fig. 16: Fluctuations of the groundwater table in response to pumpage and drought. Source: Nkhuwa, 1996
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