CyAN is a multi-agency project among EPA, the National Aeronautics and Space Administration (NASA), the National Oceanic and Atmospheric Administration (NOAA), and the United States Geological Survey (USGS) to develop an early warning indicator system to detect algal blooms in U.S. freshwater systems. This research supports federal, state, tribal, and local partners in their monitoring efforts to assess water quality to protect aquatic and human health.