The present boom in making electricity from hydroelectric sources pays no heed to some political considerations, but helps the trend continue towards renewable energy. Dams grow everywhere possible in developing countries and emerging economies, while construction companies are delighted to do the work. Apart from the national rivalries exposed by this loss of water, rivers have a lot to lose (about 20% of large free-flowing rivers currently extant) in terms of biodiversity.
The University of Copenhagen is today closing its conference on Global Challenges: Achieving Sustainability. This commendable confab is also setting up a novel Biofresh DataPortal. Massive support for indices of species and observation of the states of hydrology worldwide will be provided.
The news of doubling hydropower is the door into a new era for dams. Professor Christiane Zarfl of the University of Tübingen studied the hydropower boom at the Leibnitz Institute in Berlin and produced a database. We have compiled available data on future expected hydropower dams – to form a key foundation for evaluating where and how to build the dams and how to operate them sustainably, she reports at the congress.
20% of global electricity has been made by using renewable sources this year. 80% of that is hydropower, with 3,700 new dams about to add to that, making a total of 1,700GW available from this renewable! China, with its disputed giant Yangzi dams and many others will still be the leader of this water race. Meanwhile their dominance will be challenged by Amazon and La Plata projects in South America and Ganges-Brahmaputra dams in India and Nepal. Here is the story of the enormous DRC dam plan for the great Congo in Africa.
The river dolphins, the migratory fish, the rare amphibian and even reptiles such as turtles will be joined by countless insect species, vital to the ecosystems of rivers, who will become threatened by loss of flow. Plant species will be affected first, with the herbivores which devour them next. Specialised predators will probably disappear while those organisms requiring clean, oxygenated water will be disappearing. Prospects seem dim, but hopefully the embryonic database system will keep track better than previous attempts to map extinctions. Because it is extinction of whole river systems we are dealing with. The energy is needed, but the use of smaller dams may avoid nation fighting nation for the pure water, the power and the glory.
By Dave Armstrong