The increasing number of dams built in the last century has underlined the necessity of these constructions to the all-round development of a country. The advent of rock mechanics, engineering geology and a better understanding of materials have made it possible to construct higher and larger dams and to tackle more difficult sites. The assumptions and risks used in the theory of dam design include such unpredictable events as earthquakes, floods, and geological faults or soft seams, which may be either underestimated or completely missed during initial exploration. Incidents relating to dams are manageable at an early stage, whereas accidents, which are largely unforeseen, result in unexpected behaviour of dams and in catastrophic failures. Investigations conducted to determine the cause of a failure may not reveal the true sequence of events, while expert analyses are often controversial. From the dams that do not fail, of course, we learn nothing. Systematically monitoring the dam’s behaviour from the potential risk stage to the accident event, would allow a hazard-management programme to be implemented, minimising loss of life and property, and provide useful data.
Have reservoir fisheries been successul in replacing river fisheries? Which migration mitigation measures exist and how effective are they? What is the information base and capacity required for effective management of fisheries through a dam projcet cycle? What are the existing criteria and guidelines concerning dams and fisheries? The four papers presented in this publication address major fishery issues in relation to dams as identified by the World Commission on Dams (WCD) and FAO for the purpose of WCD's global reviews on "Dams and Development".
Dams & river regulation have become an integral part of 20th-century landscape & livelihood. Virtually every river in the lower 48 states is now regulated by dams, locks, or diversions. This report illustrates the downstream consequences of dams & explains the basis on which rivers can be scientifically managed. Following a look at a free-flowing river -- the upper Salt River of Arizona -- & its natural cycles of flow & sediment, 6 regulated rivers are examined. Each of these rivers -- the Snake, Rio Grande, Chattahoochee, Platte, Green & Colorado -- highlights a particular use of a dam or a particular downstream effect.
In 1996 the World Bank Operations Evaluation Department completed an internal review of 50 large dams funded by the World Bank. IUCN-The World Conservation Union and the World Bank agreed to jointly host a workshop in April 1997 to discuss the findings of the review and their implications for a more in-depth study. The workshop broke new ground by bringing together representatives from governments, the private sector, international financial institutions and civil society organizations to address three issues: critical advances needed in knowledge and practice, methodologies and approaches required to achieve these advances, and proposals for a follow-up process involving all stakeholders.
In the last one hundred years, a number of catastrophic events associated with rockslide dam formation and failure have occurred in the mountain regions of the world. This book presents a global view of the formation, characteristics and behaviour of natural and artificial rockslide dams. Chapters include a comprehensive state-of-the-art review of our global understanding natural and artificial rockslide dams, overviews of approaches to rockslide dam risk mitigation, regional studies of rockslide dams in India, Nepal, China, Pakistan, New Zealand, and Argentina. Rockslide dams associated with large-scale instability of volcanoes are also examined. Detailed case histories of well-known histor...
Karst terrains have been modified and adapted through a range of human activities as the need for flood control, irrigation, food production, hydropower production and other resources has increased. Successful reclamation projects require construction of dams and reservoirs. Karst terrains present the most complex working conditions for dam foundation and realization of safe reservoir space. Practical engineering solutions are extremely complex and the need for successful solution requires serious investigations and the cooperation of a wide spectrum of scientists and engineers. A wealth of data on dam projects in karst has been collected and presented in this book. Since reservoirs in karst may fail to fill despite extensive investigations and remediation treatment the book includes a description of failures as well.
The hazard posed by large dams has long been known. Although no concrete dam has failed as a result of earthquake activity, there have been instances of significant damage. Concerns about the seismic safety of concrete dams have been growing recently because the population at risk in locations downstream of major dams continues to expand and because the seismic design concepts in use at the time most existing dams were built were inadequate. In this book, the committee evaluates current knowledge about the earthquake performance of concrete dams, including procedures for investigating the seismic safety of such structures. Earthquake Engineering for Concrete Dams specifically informs researchers about state-of-the-art earthquake analysis of concrete dams and identifies subject areas where additional knowledge is needed.