Relocation and permanent evacuation of activities at flood hazard locations are nonstructural flood damage mitigation measures. These plans modify the susceptability to flood damage of flood plain activities by permanently removing them to flood free locations. The benefits from evaluation plans arise from the willingness-to-pay on the part of the removed activities and other affected parties rather than do without the plan. The purpose of this paper is to present the conceptual basis for the existence and measurement of National Economic Development (NED) benefits from permanent evacuation and relocation of flood prone activities. In addition, the paper is intended to clarify the appropriate methodology for measuring these benefits, based on established economic principles. The discussion below presents the theory of the identification of relocation benefits as a part of a broadly applicable theory of flood damage mitigation benefits. The theory indicates the sources of benefits from relocation and the relationship between NED benefits and Federally subsidized flood damage relief programs, particularly flood insurance. Subsequent sections present the past and current Corps of Engineers guidelines for the evaluation of benefits and the current practice employed in specific Corps relocation project reports.

Floods are natural hazards whose effects can deeply affect the economic and environmental equilibria of a region. Quality of life of people living in areas close to rivers depends on both the risk that a flood would occur and the reliability of flood forecast, warning and control systems. Tools for forecasting and mitigating floods have been developed through research in the recent past. Two innovations currently influence flood hazard mitigation, after many decades of lack of significant progress: they are the development of new technologies for real-time flood forecast and warning (based on weather radars and satellites) and a shift from structural to non-structural flood control measures, due to increased awareness of the importance of protecting the environment and the adverse impacts of hydraulic works on it. This book is a review of research progress booked in the improvements of forecast capability and the control of floods. Mostly the book presents the results of recent research in hydrology, modern techniques of real-time forecast and warning, and ways of controlling floods for smaller impacts on the environment. A number of case studies of floods in different geographical areas are also presented. Scientists and specialists working in fields of hydrology, environmental protection and hydraulic engineering will appreciate this book for its theoretical and practical content.