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Surface Water Flow Trends in the Nation's Streams and Rivers

January 29, 2021
Access the Mapper

Changes in streamflow conditions can affect infrastructure, water supply, and ecosystems. The IWAAs Surface Water Flow Trends mapper provides access to information about long-term changes in low flows, mean flows, and peak flows. View national trends for the last 100, 75, or 50 years, or calculate trend values for a custom time period at an individual site.

Screenshot showing national lowest annual 7-day average streamflow trends from 1941-2015
Sources/Usage: Public Domain. View Media Details
Screenshot of the IWAAs Surface Water Flow Trends mapper, which provides access to information about long-term changes in water flow trends across the nation.