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Now that June is upon us, it’s Great Outdoors Month! So why not stream some Nature instead of Netflix? Speaking of streams, maybe you’re thinking of going kayaking, canoeing or tubing on a nearby river. Just go with the flow!


Pat Kikut and Graham Lederer
Pat Kikut and Graham Lederer move quietly by the beautiful geologic formations along the Green River. (Credit: John E. Parks, USGS. Public domain.)

Before you go, you’ll probably check the weather.  Did you know that it’s also possible to check the water conditions of your favorite river or stream? That’s thanks to the more than 8,400 USGS streamgages located in all 50 states and territories that monitor streamflow year-round.

Streamgages tell you how high the water is, how much water is flowing, and if the river is in flood or drought conditions. Although they’re helpful for knowing if conditions will be just right for your tubing excursion, these streamgages have a broader role to play in society. Information on the flow of rivers and streams is a vital national asset that safeguards lives, protects property, and helps ensure adequate water supplies for the future. 

Theses streamgages can even send information straight to your phone! Before you venture out to fish, swim or otherwise enjoy the nation’s waters, you have several options from the USGS to find out more about that water near you! The first is through USGS WaterNow, where you can sign up for alerts for current water conditions which are sent directly to your mobile phone or email. You can get information on streams, springs, wells, lakes, and/or water-quality information like temperature and pH. The second way is by checking out the USGS WaterAlert website or sign up for emails or texts to your phone when a stream exceeds a level that you set. USGS WaterAlerts can tell you not only the streamgage height, which is the height of the water in the stream above a reference point, but depending on the water body selected, you can get real-time data on the streamflow, water level, water quality and precipitation.

What is WaterAlert?

WaterAlert was developed to provide water professionals, recreationalists, and the general public the latest hydrologic conditions using USGS real-time data via email and text messaging. It can be used for floods, droughts, general water monitoring and recreational purposes.

Water Alert Facts and Numbers:

  • WaterAlert is a critical service provided by USGS that sends approximately 60,000 emails and approximately 53,000 SMS (text) messages each day. 
  • It has 116,449 subscribers and 84,894 unique users.
  • The top 5 most popular parameters set by subscribers are:
    • Streamgage height (55.7%);
    • Streamflow (32.1%);
    • Lake or reservoir water surface elevation above NGVD 1929 (2.9%);
    • Precipitation over one hour (1.7%);
    • Temperature, degrees Celsius (1.2%).

Once you know the unique ‘USGS Site Number’ for a streamgage, you can text it to USGS Water Now (text to to get an immediate update on water level, streamflow, and anything else being monitored by the streamgage.

If you have questions about WaterAlert, you can visit the WaterAlert Frequently Asked Questions page or the How to use WaterAlert and the Map Interface page to learn how to manage your account, learn more about the data parameters available for subscription, and how to search for and sign up to receive alerts from the streamgage of your choice.


Streamgages-The Source of Information: What are they, how do they work, what can they tell me?

Image: Happy Isles Streamgage
Gage house installed in 2010 at Happy Isles Streamgage with explanatory exhibits on the Merced River in Yosemite Valley. Location: Happy Isles, Yosemite National Park, California. (Credit: Al Caldwell, Public domain.)

A streamgage is a structure installed beside a stream or river that contains equipment that measures and records the water level (called gage height or stage) of the stream. Getting the streamflow, though, requires a bit of math. Streamflow (also called discharge) is computed from measured water levels using a site-specific formula calculated using? onsite water level and streamflow measurements made by USGS hydrographers.

Our hydrographers and technicians visit the streamgage and manually measure the streamflow at varying stages of the stream. All that information is fed into the formula so the streamgage can estimate the streamflow itself depending on how high the water gets. To make sure the formula is working though, we regularly do quality assurance tests and re-measure the streamflow manually (which has the side benefit of letting our technicians and scientists enjoy the Great Outdoors themselves!). All of the water level and streamflow data are also available online.

It’s not just how high the water is or how fast it’s moving. At some specific surface-water and groundwater sites, we maintain instruments that continuously record quality information too, like temperature, pH, specific conductance (which tells us about dissolved materials in the water), dissolved oxygen (which fish need to breath), and percent dissolved-oxygen saturation. To round out the picture, some of our streamgages also collect other data like air temperature and barometric pressure. Currently more than 2,200 sites transmit this data automatically, and it can be found here.

To read more about streamgages visit the USGS Streamgage Basics page. You can also follow them on Instagram at @usgs_streamgages.


Delivering the Data

The National Water Information System or NWISWeb is the underlying engine that delivers data to the public and cooperators, and which WaterAlert is built upon. It’s had approximately 31 million visits to by approximately 8 million unique users during the last year.  The real-time monitoring location pages make up about 90 percent of the web traffic. More data goes out through our application program interfaces (APIs) at than goes out through the website. Major users of the APIs includes NOAA’s National Weather Service, who uses USGS streamgage data for flood forecasting; and the U.S. Bureau of Reclamation, who uses streamgage data to manage operations of dams and hydropower operations in the Colorado River Basin.

Now, water you waiting for, enjoy the outdoors! My streamgage is 01646000, on Difficult Run in Virginia! Find yours at USGS WaterAlert

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