Why might USGS streamflow data be revised?
Real-time USGS streamflow data are PROVISIONAL, meaning that the data have not been reviewed or edited. These data might be subject to significant change and are not official until reviewed and approved by the USGS.
Real-time streamflow data can be affected by:
- backwater from ice or debris such as log jams
- algae and aquatic growth in the stream
- sediment movement
- malfunction of recording equipment
Data are reviewed periodically to ensure accuracy. Each station record is considered PROVISIONAL until the data are published. The data are usually published within 6 months of the end of the water year.
Data users are cautioned to consider the provisional nature of the information before using it for decisions that concern personal or public safety or for business that involves substantial monetary or operational consequences.
Learn More: Streamgaging Basics
Related
Sometimes the USGS real-time stage data seems too high (or too low). Are the USGS data inaccurate? Sometimes the USGS real-time stage data seems too high (or too low). Are the USGS data inaccurate?
There can be occasional equipment or database problems where erroneous data are reported for short periods of time until corrections can be made. This is why it is important to look at a record of streamflow (like the 7-day hydrograph plots) rather than a single point in time. However, most of the time the USGS has a high level of confidence in its real-time stage data. During low streamflow...
Where can I get real-time and historical streamflow information? Where can I get real-time and historical streamflow information?
Water Data for the Nation (WDFN) is the home for USGS streamflow, groundwater, and water quality data. Through WDFN you can find different tools to look at historic and real-time streamflow data, find sites of interest, and access using USGS water data application programming interfaces (APIs). State pages (e.g., California) allow you to discover real-time data in your state, or you can create a...
Why do some real-time streamgaging stations stop transmitting data for extended periods of time? Why do some real-time streamgaging stations stop transmitting data for extended periods of time?
The USGS usually corrects any equipment or station problems at our streamgages within a few days of their occurrence. Occasionally, replacement parts or equipment might not be readily available, or a station might be inaccessible due to weather conditions. Most USGS streamgaging stations are operated in cooperation with other agencies. At some stations, the stage transmitting equipment is owned...
How often are real-time streamflow data updated? How often are real-time streamflow data updated?
USGS real-time streamflow data are typically recorded at 15-minute intervals, stored onsite, and then transmitted to USGS offices once every hour, depending on the data relay technique used. Recording and transmission times might be more frequent during critical events (floods, for example). Data from current sites are relayed to USGS offices via satellite, telephone, and/or radio telemetry and...
Related
Sometimes the USGS real-time stage data seems too high (or too low). Are the USGS data inaccurate? Sometimes the USGS real-time stage data seems too high (or too low). Are the USGS data inaccurate?
There can be occasional equipment or database problems where erroneous data are reported for short periods of time until corrections can be made. This is why it is important to look at a record of streamflow (like the 7-day hydrograph plots) rather than a single point in time. However, most of the time the USGS has a high level of confidence in its real-time stage data. During low streamflow...
Where can I get real-time and historical streamflow information? Where can I get real-time and historical streamflow information?
Water Data for the Nation (WDFN) is the home for USGS streamflow, groundwater, and water quality data. Through WDFN you can find different tools to look at historic and real-time streamflow data, find sites of interest, and access using USGS water data application programming interfaces (APIs). State pages (e.g., California) allow you to discover real-time data in your state, or you can create a...
Why do some real-time streamgaging stations stop transmitting data for extended periods of time? Why do some real-time streamgaging stations stop transmitting data for extended periods of time?
The USGS usually corrects any equipment or station problems at our streamgages within a few days of their occurrence. Occasionally, replacement parts or equipment might not be readily available, or a station might be inaccessible due to weather conditions. Most USGS streamgaging stations are operated in cooperation with other agencies. At some stations, the stage transmitting equipment is owned...
How often are real-time streamflow data updated? How often are real-time streamflow data updated?
USGS real-time streamflow data are typically recorded at 15-minute intervals, stored onsite, and then transmitted to USGS offices once every hour, depending on the data relay technique used. Recording and transmission times might be more frequent during critical events (floods, for example). Data from current sites are relayed to USGS offices via satellite, telephone, and/or radio telemetry and...