Dam Performance and Safety
As dams get old they become increasingly more expensive to maintain. Worldwide, there is systematic underfunding of dam maintenance. No figures are available for the cost of making the world's dams safe. A ballpark figure for the global under-investment in dam safety would be $300 billion.
Most alarmingly, the world's more than 54,000 existing large dams have not been built to allow for the erratic hydrological patterns that climate change is bringing. In this sense, all dams should now be considered unsafe. More extreme storms and increasingly severe floods will have major implications for dam safety. In addition, there is increasing concern that dams can trigger earthquakes as a result of the weight of the reservoir, among other factors. Earthquakes also increase the probability of dam failure and the risk of downstream flooding.