FutureDAMS research consortium: environmental flow mini review

The infrastructure that supports agricultural irrigation, domestic water supply and hydroelectric power generation threatens the sustainability of rivers, yet these are key ecosystems. Hydropower dams affect the amount of water in the river as well as the variability in flow. These changes have negative impacts on aquatic habitats and biodiversity and fundamental ecological processes may be impaired. Because humans derive goods and services from river ecosystems, it is necessary to manage river flows sustainably. ‘Environmental flows’ can be defined as the hydrological regime required to sustain river and associated water dependent ecosystems, and the human livelihoods and well-being that depend on them. Environmental flows are derived through a combination of approaches including hydrological or hydraulic analyses and habitat simulations. Current approaches are holistic and consider the whole of the ecosystem and its biodiversity as well as socioeconomic links. The World Bank has recently issued extensive guidance for hydropower projects that provides tools for decision making and a rigorous framework for establishing environmental flows. However there remains a number of critical research areas such as predictive flow-response modelling, upscaling of patterns at the basin scale and deciphering the multiple stressor environment found in rivers.