The Challenge of Water Supply in Urban Lagos under Increasing Climatic Variability
This study examines the impact of climate, urbanization, and population on water supply in Lagos State. Population and water production data in Lagos State between 1963 and 2006 were collected, and used for time series analyses. Multi-temporal land-sat images of 1975, 1995 and NigeriaSat-1 imagery of 2007 were used for land use change analysis. The population of Lagos State increased by about 557.1% between 1963 and 2006, correspondingly, safe water supply increased by 554%. Currently, 60% of domestic water use in urban areas of Lagos State is from groundwater while 75% of rural water is from unsafe surface water. Between 1975 and 2007, urban land use increased by about 235.9%. The 46years climatic records revealed that temperature and evaporation decreased slightly while rainfall and relatively humidity decreased consistently. Urban land use is expected to increase by 20% with expectation of serious congestion in the suburb areas. Based on these trends and using 4% annual growth rate of the Lagos State population, the required water is expected to increase to about 19.8million and 3,213,058m3/d respectively by the year 2026. The implication is that the percentage of unaccounted residents to public pipe borne water in Lagos may increase to over 65% in the nearest future while citizens have to provide about 50% of their required water through boreholes and dug wells (in the urban area), and rivers, streams, and ponds (in the rural areas).