What does the term "stream stage" mean?
Stream stage is an important concept when analyzing how much water is moving in a stream at any given moment. "Stage" is the water level above some arbitrary point in the river and is commonly measured in feet. For example, on a normal day when no rain has fallen for a while, a river might have a stage of 2 feet. If a big storm hits, the river stage could rise to 15 or 20 feet, sometimes very quickly. This is important because past records might tell us that when the stage hits 21 feet, the water will start flowing over its banks and into the basements of houses along the river -- time to tell those people to move out! With modern technology, the USGS can monitor the stage of many streams almost instantly.
Hydrologists are also able to convert stage height into streamflow volume by determining a rating curve for each site.
Related Content
Is there a way to get alerts about streamflow conditions?
Why does the USGS use the spelling "gage" instead of "gauge"?
How can I obtain river forecasts (flood forecasts)?
Does "stage" tell you how much water is flowing in a stream?
Why are there sometimes differences between USGS and National Weather Service river stages?
Sometimes the USGS real-time stage data seems too high (or too low). Are the USGS data inaccurate?
Where can I get real-time and historical streamflow information?
Where can I find flood maps?
The Vital Nature of Streamgaging
Gary Moore spent the last three days of 2015 stacking hefty bags of sand in front of a fellow church member’s brick home. With only 1,000 feet between the house and the swelling Mississippi and Meramec Rivers, Moore and other volunteers worked quickly, in frigid temperatures, to assemble a 10-foot high, 1,000-foot-long sandbag wall to ward off floodwaters.
Fighting the Floods
The USGS response to the Louisiana floods is part of the larger USGS flood science mission...
Stay Current on Your Rivers with USGS WaterNow
For the first time, anyone can find out the current conditions on thousands of rivers and streams across the country, right from their phone, using USGS' latest system WaterNow.WaterNow makes the water conditions monitored by more than 16,000 streamgages and other sites across the country available via text or email.
Reading stream stage at Bull Lake Creek above Bull Lake streamgage
The wire weight is lowered to determine stage of Bull Lake Creek above Bull Lake
USGS staff gage measuring the height of the water in the Carson River
USGS staff gage (ruler) measuring the height of the water, on the Carson River, near Brunswick Canyon, Nevada.
Cork line from a crest-stage gage
Photo of a cork line from a crest-stage gage. As waters rise inside the crest-stage gage, the cork floats on the top of the surface. When waters recede, the cork line is deposited as the water inside the gage begins to fall, marking the highest water level. (From Identifying and preserving high-water mark data,
...Staff gage on a Wisconsin stream
Staff gages, like this one, are attached to fixed structures. Field crews visually read and record the water-level height (stage) of the stream periodically.
Staff Gage at Bonnet Carré Spillway
A staff gage at the Bonnet Carré Spillway, which is managed by the U.S. Army Corps of Engineers.
In late 2015/early 2016, unusually large rainfall in the Upper Mississippi River Valley led to flooding throughout Arkansas, Illinois, Louisiana, Mississippi, Missouri, and Tennessee. USGS water science centers responded to the flooding by measuring the streamflow,
...USGS streamgage measures flooding in the lower Trinity River
A USGS streamgage measures flooding in the lower Trinity River, Texas.
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USGS employee, Hanna Coy, talks about stream gauging.
Stage Discharge Ratings Class
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USGS Red River of the North at Fargo Streamgage
Water level measurement from the USGS Red River of the North at Fargo streamgage in downtown Fargo, ND. The water level peaked at around 39 feet at this streamgage on April 9. Real-time water level and streamflow data from this gage can be accessed online.
Streamgages: The Silent Superhero
Whether you drink water from your tap, use electricity or canoe down your local river, chances are you benefit from USGS streamgage information. So what is a streamgage and what does it do for you? This CoreCast episode gives you the inside scoop on your silent superhero.
Transcript and captions available soon.
USGS Storm Words: River Stage
The USGS has many missions before, during and after a major storm. Here is an explanation of a word we commonly use with our science.
River Stage: Is the water level measured in feet above a point, usually somewhere below the river bed. The USGS’ real-time streamgage network is able to indicate when a monitored river reaches a stage where the water will start
...USGS Storm Words: Rating
The USGS has many missions before, during and after a major storm. Here is an explanation of a word we commonly use with our science.
Is the relationship between river stage and discharge. For many rivers, as stage rises so does the discharge, therefore, ratings are necessary because USGS scientists cannot always be at the 8,200+ nationwide streamgages to measure
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