Stage-discharge rating curve software

News Releases. Featured Stories. Science Snippets. Technical Announcements. Employees in the News. Get Our News. Media Contacts. I'm a Reporter. Staff Profiles. Social Media. Contact Us. They also measure high flows whenever they happen. USGS computers are used to apply the stream-discharge rating curve for a given streamgage to the continuous water level stage data for the gage to estimate continuous streamflow discharge for the site.

For some rivers, the typical stage-discharge relation does not apply, because stage is not uniquely related to discharge due to tides, low slope, or density currents. The advent of hydroacoustic or ultrasonic velocity meters has made it possible to continuously monitor discharge at these types of streams using the index velocity method.

In this method, a hydroacoustic or ultrasonic velocity meter is placed in the river to continuously monitor the water velocity for a section of the river; this is called the index velocity. Periodic discharge measurements are paired with the index velocity to develop a relation between the index velocity and the mean velocity.

This index velocity versus mean velocity relation is used along with a continuous record of the stage and a stage versus cross-sectional area relation to determine the continuous record of discharge at the site. The National Water Dashboard NWD is a mobile, interactive tool that provides real-time information on water levels, weather, and flood forecasts - all in one place on a computer, smartphone, or other mobile device.

The NWD presents real-time stream, lake and reservoir, precipitation, and groundwater data from more than 13, USGS observation stations across the country. The U. Geological Survey WaterAlert service sends e-mail or text SMS messages when certain parameters, as measured by a USGS real-time data-collection station, exceed user-definable thresholds.

The development and maintenance of the WaterAlert system is supported by the USGS and its partners, including numerous federal, state, and local agencies. Current data typically are recorded at to minute intervals, stored onsite, and then transmitted to USGS offices every 1 to 4 hours, depending on the data relay technique used.

Recording and transmission times may be more frequent during critical events. WaterWatch displays maps, graphs, and tables describing real-time, recent, and past streamflow conditions for the United States, including flood and droughts. Real-time information generally is updated on an hourly basis. FPS are monitoring stations that track the amount of water in streams and rivers across the Nation to meet long-term federal information needs.

They are strategically positioned to serve as a backbone for the larger National Streamflow Network that is operated in cooperation with over 1, federal, state, tribal, and local agencies. This mapper provides access to over 1.

The user sends an email or text message containing a USGS current-conditions gaging site number, and will quickly receive a reply with the station's most recent data for one or more of its monitored parameters. Information on the flow of rivers is a vital national asset that safeguards lives, protects property, and ensures adequate water supplies for the future. The USGS is the federal agency responsible for operating a network of about 7, streamgages nationwide.

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Measure the height of the water with your ruler. Record the total amount of water in the cup and depth of the water. Repeat steps 1 — 3, 5 times. Be sure you have a large range of water depths ranging from almost empty to full. Repeat the above steps with your second water vessel.

Plot your results for each water vessel separately. Put the depth of water on the x-axis and the volume on the y-axis. Add a best fit line to your plot. Include these two plots in your Assessment submission. What is the primary factor controlling the difference between the two volume-stage relationships you developed in the hands on activity? Ensure Stage is on the x-axis and Discharge is on the y-axis Add a power trendline and display equation on the graph.

Synthesis Questions: Using the rating curve and hydrograph you developed above 35 pts Using the rating curve you created, answer the following questions: What is the discharge at this site for a stage of 3.

If so, what is the discharge? If not, why? In 2D models, on the other hand, water surface elevations can vary at each computational grid.

See the image below for an example of a cross section that has been cut from a 2D model. The water surface elevation varies across the section:. Depending on your mesh resolution, any given cross section could have dozens or even hundreds of different stage hydrographs. To develop a stage-discharge relationship in a 2D model, we therefore need to measure the water surface elevation at the single computational grid element that lies closest to our gauge location.

While stage can be measured at this single point, there can be no flux through a dimensionless point, so we will need to draw a cross section along which to compute discharge.

In a 1D model, this will already have been done; for 2D models, however, we do this by defining a profile line. The net flux across the profile line will then be computed based on the resultant velocity vectors for each face point along the profile alignment. We can orient the profile line any way we wish if it passes through the gauge location point and spans the entire wetted channel; the flow direction and the slope of the water surface will be computed independently of the alignment that we select for our profile line.

Structures modelled in 1D give you the option of displaying tailwater or backwater curves at each structure. As shown by the tailwater curves, any given stage can correspond to a wide range of discharge rates.

Unless you add energy, pressure, or some driving force that affects your energy slope, your upper discharge limit will be the free flow curve.

Unless reverse flow is involved, the lower discharge limit for any given stage is zero. The backwater profile shown in the image below represents flowing water as indicated by the difference between the energy line and the water surface elevation upstream of the bridge ; but a horizontal backwater profile could just as well result from a downstream obstruction that submerges the bridge with no incoming flow at all in which case the energy line and water surface elevation profile would be coincident.

That is why a tailwater curve can contain points along the vertical axis, but no points would be plotted along the horizontal axis. If your downstream boundary was a large, static body of water, for instance, you might have a standing water at the structure long after the upstream inflow has receded to nothing.

If the stage is measured simply as the water surface elevation without accounting for the velocity head, we could theoretically generate points to the right of the free-flow curve.