DRINKING WATER QUALITY AND PROVISION IN LOW-INCOME, PERI-URBAN COMMUNITIES OF LUSAKA, ZAMBIA

Lusaka, Zambia, is a rapidly growing city with over 2 million people. About 65% of the population lives in low-income, periurban communities. Most of their water supply comes from vulnerable, aquifer systems, severely impacted by human activities, especially waste disposal and sanitation. Water-borne disease is frequent. In the early 2000s, CARE International partnered with the Zambian government to establish Water Trusts in several communities to be run by community residents. The Water Trusts extract groundwater from relatively deep boreholes and deliver it to numerous public tap stands. Vendors sell the water at limited times of the day for about $0.02 per 20 L; the money is used to run and expand the water delivery systems. Some residents, however, acquire water from shallow, hand-dug wells. Research goals were to 1) assess the quality of water provided by the Water Trusts compared to water in the shallow wells, 2) assess the coverage provided by the Water Trusts, 3) explore why some residents might still acquire their drinking water from the shallow wells, 4) document the reported extent of water-borne disease, 5) explore the relation of shallow water contamination to the bedrock geology and 6) use groundwater dye tracing to investigate the nature of the karst system. Water quality was assessed in six communities measuring concentrations of E. Coli bacteria and nitrate. Water Trust coverage and attitudes towards different water sources were assessed with surveys given to Water Trust managers. Groundwater dye traces were conducted in similar geological settings in less populated areas to assess conduit connectivity and groundwater velocities.

Water Trust-supplied water was generally high quality. Shallow well water had high nitrate and E. coli concentrations indicating contamination from nearby pit latrines. Contamination was worse in the more karstic formations. Dye traces, however, indicated that direct influence through large connected conduits is not rapidly occurring. Water Trust managers reported that among the six communities, the percentage of people served ranged from 14 to 95% and averaged 55%. Many residents rely on the shallow well water due to the convenience (close by and always open) and the cost. There is much greater incidence of water-borne disease among residents drinking shallow well water.