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Petts, G. E. (1989). Perspectives for ecological management of regulated rivers. Pages 3-24 in J. A. Gore and G. E. Petts, eds. Alternatives in Regulated River Management, CRC Press, Inc., Boca Raton, Florida (USA).

Since about 3000 B.C., efforts have been made to regulate rivers for the benefit of agriculture. Now many other purposes are cited, including flood control, industrial uses, navigation, fisheries, and recreation and leisure. The ecological impact of river regulation schemes is considered, including a conceptual framework for the evaluation of that impact, tools available for mitigation of effects and even enhancement of river ecosystems, and problems of implementing policies for the ecological management of regulated rivers. Regulation of the Zambezi River is emphasized as an example. Assessment of the environmental impact of river regulation requires consideration of spatial dimensions (global and catchment scales) and the temporal dimension. Three approaches to potentially harmful river regulation schemes have been recognized: (1) preserving a portion of wild river; (2) secondary regulation, in which additional structural measures and special operation rules are employed; or (3) compensation schemes (e.g., fish ponds to compensate for lost fish). Of these, secondary regulation should be considered first. Measures available include flow modifications, water quality control, channel design and maintenance, fish passage, biological alternatives (e.g., stocking), and controls on human activities. It has been argued that in developing nations the pressures for agricultural development should take precedence over concerns about environmental impacts from river regulation. This view does not recognize that sustainable development requires environmentally sound management. As illustrated by the approach taken in Zambia , development activities and environmental management can be integrated.