What is a flow duration curve?

A flow duration curve (FDC) is a graphical representation that shows the relationship between streamflow rates and the percentage of time that those rates are equaled or exceeded over a specific period. It is commonly used in hydrology and water resource management to assess the variability and reliability of water flow in a river or stream. The curve helps in understanding patterns of water availability, aiding in the design of water infrastructure and management strategies. By analyzing the FDC, stakeholders can make informed decisions regarding water allocation, environmental flow requirements, and flood control.