Upgrading mechanical and electrical systems

In carrying out maintenance and rehabilitation investigations of three large overseas dams, there was a need to address the issue of providing up-to-date technology against sustainability. The dams were built in the 1970s and used proven technology from that period. As a result of reduced investment, maintenance had been neglected for some time, resulting in much of the dam equipment being relegated from automatic to manual operation; in some cases, relying on operator knowledge and use of ‘work-arounds’. The challenge for the investigation was to return the dam equipment to full functionality and take advantage of developments in technology, while providing a sustainable solution. The balance between a state-of-the-art technical solution that meets accepted international standards and practices, and operational sustainability can be difficult to attain, particularly in developing countries. The experience and knowledge of engineers who design or manage dams can encourage the use of innovative solutions, which may be at odds with the knowledge and training of those maintaining the dam, and availability of spare parts and service support. This paper will discuss how the balance of sustainability, reliability and redundancy affects the choice of design and, through examples, why there may not always be a single solution.