Big Questions

We should build more dam particularly in developing countries in Africa, Latin America and Asia. Dam can not only produce hydroelectricity but also provide important services including flood control, drought alleviation, water supply, and navigation. In the United States, only 2,066 (2%) out of 82,642 dams of all size are primarily used for hydropower. Large dams can protect densely populated countries from serious flood damage. The flood conditions downstream the Three Groges Dam in 1998 and 2012 are totally different with the flood storage of the TGD. In the era for developing new energy to adapt to climate change, hydropower can contribute to the stability of the electrical system by providing the full range of ancillary services required for the high penetration of variable renewable energy sources, such as wind and solar. Of course dam will result adverse environmental and social impacts including natural flow alternation, fragment of habitat, disruption of fish migration and resettlement. So the scientists, engineers and sociologist have been working for decades to assess the impacts and implement mitigation measures to avoid, mitigate and compensate these adverse impacts. It is easy to say no but is quite difficult to give solution or constructive suggestion. If we can find a solution which is better than dam in the aspect of electricity production and water operation, we won't build more dam. But who can?