Flood Information and Data

For more than 100 years, the USGS has played a critical role in reducing flood losses by operating a nationwide streamgage network that monitors the water level and flow of the Nation’s rivers and streams. Through satellite and computer technology, streamgages transmit real-time
information, which the National Weather Service (NWS) uses to issue flood warnings. Streamgages provide long-term data that scientists need to better understand floods and to define flood-prone areas as well. Streamgage data also help in designing structures resilient to flooding and are the basis for the Federal Emergency Management Agency’s (FEMA) National Flood Insurance Program, the only Federal insurance program for natural hazards.