Green Hills, Blue Cities

Rainwater harvesting is promoted and implemented in urban areas for a variety of reasons. In Port Harcourt, water supplies have been diminishing due to limited capacity by the central government. This has spurred house-owners to invest in rainwater harvesting for household consumption. The increased use of rainwater harvesting provides additional water supply and reduces pressures of demand on surrounding surface and groundwater resources. Access to groundwater through boreholes is widespread but largely unmonitored in Africa. In Nairobi, there is a growing demand for groundwater, which is tapped through boreholes. Desalinisation is not widely used as an alternative source of water. Algeria, through the Hamma Seawater Desalination Plant, is one country that uses desalinised water (Ondrey 2008). Africa’s cities are highly diverse, and as such they face unique challenges in as far as access to improved drinking water and sanitation are concerned. As the case studies in this publication demonstrate, the following are some common water and sanitation issues in African cities: • Cities are depending more on external ecosystems for their water supplies; • Alternative sources of water such as rainwater harvesting and groundwater are growing in use and importance; • There is a growing role by the private sector in complementing government efforts in the delivery of urban water supply and sanitation; • Management of urban water is being reformed in view of changes in economic development and growing environmental awareness; and • The plight of the urban poor is known, but there are few pro-poor initiatives to improve their access to water and sanitation service. The case studies present urban water challenges in African cities, and highlight approaches adopted to reduce the impacts of urbanisation on water and ecosystems. The case studies discuss urbanisation characteristics of their respective cities, state and trends of water withdrawals and demand, environmental impacts of bulk water supply and wastewater discharge, and lessons for policy. CASE STUDIES

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