of the increasing number of large dams being constructed on less than ideal foundations. In addition, historical evidence indicates that effective dam safety programmes could have prevented the majority of dam incidents progressing to dam failures.
Dam failures continue to occur worldwide emphasising the need for on-going vigilance. Examples of recent dam failures include Shih-Kung Dam, Taiwan which suffered extensive damage in an earthquake in September 1999 and Zeyzoun Dam in Syria which failed in June 2002. Details of dam incidents are contained in“ Dams and Public Safety”( Jansen, 1983),“ Deterioration of Dams and Reservoirs( ICOLD, 1983) and“ Lessons from Dam Incidents”( ICOLD 1974).
Current Dam Safety Management Practice
The current dam safety management practice in the country is largely by self regulation. There is no specific law on dam safety. There is no regulatory body to regulate activities on dam development and operation. Majority of the dam owners practice a limited number of elements of the Dam Safety Management System( DSMS). The standards and resources employed by dam owners vary considerably. There is a lack of an overall management system to implement dam safety activities, decision making processes and capacity building among dam owners in the country.
Dam safety management should cover both the assurance of quality in design, construction, surveillance and safety review throughout the life of a dam. The primary objective is preventing dam failure. It also involves preparing to respond to unusual conditions so that hazardous situations can be brought under control. The DSMS should reflect the owner’ s dam safety policy and provide a structured framework for conducting dam safety activities and addressing dam safety issues. A DSMS should incorporate:
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A dam safety policy, dam safety statement or dam safety standard.
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A description of the elements of the DSMS, dam safety management activities and resources for completing these activities.
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Responsibilities and procedures for implementing the DSMS
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Procedures for checking and reviewing the performance of the dam and the DSMS.
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Procedures for implementing corrective actions on deficiencies and nonconformance.
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Procedures for regular reporting of the performance of the dam and the adequacy of the DSMS to the owner and where appropriate, the regulator.
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Supporting systems for management, staff training, communications, information management and continuous improvement.
The DSMS should incorporate arrangements for governance, a good internal organisational structure, a clear decision-making process, competent staff, and key project data and records. An example of a DSMS is presented in Figure 1.
Deficiencies Of Current Dam Safety Management Systems
The key elements in a DSMS should include the following:
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Accountability
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Personnel competencies
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Operation and maintenance
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Surveillance
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Dam safety reviews
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Special inspections and dam safety reviews
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Emergency preparedness
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Identifying and managing dam safety issues
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Information management
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Audits and reviews
Countries with dam safety regulations typically stipulate the elements that must be included in the dam safety assurance programme. An effective DSMS not only provides a framework for a dam owner to assure safe dam operation, but also supports asset management and allows owners to maximise the value of the asset.
Currently, most dam owners do not have an established DSMS or practice a limited numbers of the key elements. Common cases of nonconformances or deficiencies of local DSMS which are not in line with good international practice include:
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