Most hydropower potential has been fully exploited in developed countries, with the remaining water systems often being protected. However, large growth is expected in developing countries, as found in the 2009 UN World Water Development Report. Some countries such as Lao and Congo have the potential to be the “batteries” of their respective regions, due to steep mountains and vast water systems. However, many hydro dams are fiercely contested due to their restriction of water flows in a river basin and the knock-on impacts for livelihoods such as fisheries, as well as the displacement of biodiversity and communities due to the creation of reservoirs.
To find a way to balance the environmental and social risks with that of creating renewable energy, IUCN is monitoring the Hydropower Sustainability Assessment Forum which aims to establish a broadly endorsed sustainability assessment tool to measure and guide performance in the hydropower sector using many (but not all) of the findings from the World Commission on Dams (which IUCN helped establish). IUCN gives particular focus to encouraging the hydropower sector to sustainably manage upstream watersheds and to implement environmental flows that maintain downstream ecosystems and the services they provide to people.
IUCN works on projects throughout the world that demonstrate the importance of maintaining flows in all river systems including those with dams. For example, in the Huong Basin in Vietnam, a flow assessment made clear how changes in the river flow affected both economic returns and ecosystem health. Basin authorities were able to determine which options accommodated economic goals while protecting downstream ecosystems and their services.
The application of environmental flows enables integrated decision-making about use of water within the limits of availability to meet priorities for economic growth, sustainable livelihoods and conservation, thereby increasing the sustainability of water infrastructure including hydropower.
