USGS Streamgaging Network Active

Sources/Usage: Public Domain.

In the late 1800s, John Wesley Powell, second Director of the U.S. Geological Survey (USGS), proposed gaging the flow of rivers and streams in the Western United States to evaluate the potential for irrigation. Around the same time, several cities in the Eastern United States established primitive streamgages for use in designing water-supply systems. Streamgaging technology has greatly advanced since the 1800s, and USGS hydrographers have made at least one streamflow measurement at more than 37,000 sites throughout the years. Today, the USGS Groundwater and Streamflow Information Program supports the collection and (or) delivery of both streamflow and water-level information at approximately 8,500 sites (continuous record) and water-level information alone or partial record streamflow at approximately 2,900 additional sites. The data are served online—most in near realtime—to meet many diverse needs; more than  880 million requests for streamflow or water level information were fulfilled during the  2020 water year (Oct. 1, 2019‒Sept. 30, 2020).

Unique Partnership

The streamgages are primarily operated and maintained by the USGS, but most are funded in partnership with one or more of about 1,800 Federal, State, local, and Tribal agencies or organizations. This unique cooperation results in nationally consistent and impartial data that also aids local decision making. The shared costs result in the operation of far more streamgages than would be possible if financed solely by USGS appropriations, which provide less than one-third of the needed funding. These partnerships also enable fixed costs (such as costs associated with data storage and delivery infrastructure) to be broadly distributed, resulting in more economical streamgaging information for all.

“The independent, science-based streamflow information that we obtain from USGS gages is paramount to assuring compliance under our various interstate compacts with our neighboring states.”
Julie Cunningham, Oklahoma Water Resources Board

“Many thanks … we sincerely appreciate your [USGS] support. Your data makes our forecasts possible.”
Kevin Low, National Weather Service, Missouri River Basin Forecast Center Hydrologist, May 25, 2018

A Network of Networks

The USGS streamgaging network is a multipurpose network that comprises more than 10,000 streamgages. It encompasses several smaller networks that produce specific information or support specific needs.

National Streamflow Network (NSN). The National Streamflow Network (NSN) consists of all streamgages that continuously monitor streamflow year-round and from which daily mean streamflows are computed and made available online. The data collected at NSN streamgages serve several functions (including flood warning, water allocation, and recreation) and can be used by anyone regardless of whether or not they help fund the network. The use of consistent methods enables data from the many gages to be combined, expanding the use and value of the data from every gage. At present (2020), approximately 8,500 gages are in the NSN.

Federal Priority Streamgages (FPS). The Federal Priority Streamgages (FPS) Network (previously known as the National Streamflow Information Program) was conceived in 1999 to be a core, federally funded network. The original network design included 4,300 then active, previously discontinued, or proposed new gages that were strategically positioned across the country to address long-term Federal information needs (such as supporting National Weather Service flood forecasts, or interstate and international compacts and decrees). At present (2020), more than 4,700 locations meet the criteria for inclusion in the FPS network, but only about 3,500 FPS are active because of funding limitations. These active FPS are supported through a combination of Federal and partner funding—approximately 35 percent of the active streamgages are fully funded by the USGS.