Environmental flows used to ensure sustainable freshwater use and supply

Environmental flows or E-flows, describe the quantity, quality and timing of water flows needed to sustain freshwater ecosystems so they can continue to provide services to society.
The E-flow calculators help scientists and decision makers better understand how much water remains for supply and use in a river basin or other system, and has been put to use in basins across the world.

Globally, the Food and Agriculture Organization of the United Nations (FAO) has launched an E-flow guideline, developed together with the International Water Management Institute (IWMI) and the CGIAR Research Program on Water, Land and Ecosystems (WLE), and available here.

The guidelines and data generated have been used to monitoring ‘water stress’, alleviating water scarcity, which is caused when water withdrawal outpaces supply and replenishment. Learn more about the Sustainable Development Goal 6.4.2 here.



Learn more about the first desktop tool for E-flow assessment, the Western Nepal E-flows calculator.