Flow on the Allegheny River (Cubic feet per second) Speed via cross- sectional area (Miles per hour) Measured and rescaled speed on the Southern shore of the Allegheny river between 7th and 9th Street (Miles per hour) 5,000.18.15: 10,000.36.3: 15,000.54.45: 20,000.72.60: 25,000: 0.9.75 New discharge measurements plotted on an existing stage-discharge relation graph would show this, and the rating could be adjusted to allow the correct discharge to be estimated for the measured stage. The stage is then measured inside the stilling well using a float or a pressure, optic, or acoustic sensor. USGS computers use these site-specific rating curves to convert the water-level data into information about the flow of the river. Subsection width is generally measured using a cable, steel tape, or similar piece of equipment. And I don’t know any way to figure out what that speed difference would be. An electronic signal is transmitted by the meter on each revolution allowing the revolutions to be counted and timed. The ADCP allows discharge measurements to be made in some flooding conditions that were not previously possible. Purchased from the W. & L. E. Gurley Company, Troy, New York.Object ID: USGS-000458. In recent years, advances in technology have allowed the USGS to make discharge measurements by use of an Acoustic Doppler Current Profiler (ADCP).
U.S. Geological Survey CFS or Cubic Feet per Second is the unit of measurement used for determining the “speed” of a river. An ADCP uses the principles of the Doppler Effect to measure the velocity of water. Public domain. The ADCP is then guided across the surface of the river to obtain measurements of velocity and depth across the channel.
A third mechanical current meter, also a variation of the Price AA current meter, is used for measuring water velocity beneath ice. The USGS operates over 8,200 continuous-record streamgages that provide streamflow information for a wide variety of uses including flood prediction, water management and allocation, engineering design, research, operation of locks and dams, and recreational safety and enjoyment. With this said, CFS is very important to be aware of as different levels will give you different experiences on the water. In this method, the stream channel cross section is divided into numerous vertical subsections. CFS stands for cubic feet per second which is a unit of measurement referring to the volume and speed of water flow. Streamgaging involves obtaining a continuous record of stage, making periodic discharge measurements, establishing and maintaining a relation between the stage and discharge, and applying the stage-discharge relation to the stage record to obtain a continuous record of discharge. The ADCP also uses acoustics to measure water depth by measuring the travel time of a pulse of sound to reach the river bottom at back to the ADCP.
Most USGS streamgages transmit stage data by satellite to USGS computers where the stage data are used to estimate streamflow using the developed stage-discharge relation (rating). Credit: Justin Bongard, U.S. Geological Survey. These velocity and depth measurements are used to compute the total volume of water flowing past the line during a specific interval of time. Discharge is the volume of water moving down a stream or river per unit of time, commonly expressed in cubic feet per second or gallons per day. The 14.5 feet the announcer is referring to is the stream stage. ; UPDATE November 1, 7:15 pm ET: Real-time data delivery to NWISWeb has been restored at this time. Numerous types of equipment and methods are used by USGS personnel to make current-meter measurements because of the wide range of stream conditions throughout the United States.
Because the rate at which the cups revolve is directly related to the velocity of the water, the timed revolutions are used to determine the water velocity. The sound is transmitted into the water from a transducer to the bottom of the river and receives return signals throughout the entire depth. The Price AA current meter has a wheel of six metal cups that revolve around a vertical axis. The measured stage value is stored in an electronic data recorder on a regular interval, usually every 15 minutes. In general, river discharge is computed by multiplying the area of water in a channel cross section by the average velocity of … However, the USGS has more accurate ways of determining how much water is flowing in a river. The Doppler Effect is the phenomenon we experience when passed by a car or train that is sounding its horn. Below are other science topics associated with measuring streamflow. One method that has been used for decades by the USGS for measuring discharge is the mechanical current-meter method. Its dimensions allow it to fit easily through a small hole in the ice, and it has a polymer rotor wheel that hinders the adherence of ice and slush.
7.45 1.91 sdww01. The total discharge is then computed by summing the discharge of each subsection. Page Contact Information: Colorado Water Data Maintainer However, it is not practical for a streamgage to continuously measure discharge. The velocity of the streamflow can be measured using a current meter. BENT CANYON CREEK AT MOUTH NEAR TIMPAS, CO. PURGATOIRE RIVER AT ROCK CROSSING NR TIMPAS, CO. COLORADO RIVER BELOW BAKER GULCH NR GRAND LAKE, CO, GRAND LAKE OUTLET BLW CHIPMUNK LN AT GRAND LK, CO. COLORADO RIVER BL SHADOW MOUNTAIN RESERVOIR, CO. WILLOW CREEK BELOW WILLOW CREEK RESERVOIR, CO. FRASER RIVER AT UPPER STA, NEAR WINTER PARK, CO. ELK CREEK AT UPPER STATION, NEAR FRASER, CO, MEADOW CREEK BLW MEADOW CREEK RES NR TABERNASH, CO, MEADOW CREEK DIVERSION NEAR TABERNASH, CO, RANCH CREEK BLW MEADOW CR NR TABERNASH, CO, FRASER RIVER BLW CROOKED CR AT TABERNASH CO. COLORADO RIVER AT WINDY GAP, NEAR GRANBY, CO. WILLIAMS FORK ABOVE DARLING CREEK, NEAR LEAL, CO, SOUTH FORK OF WILLIAMS FORK NEAR LEAL, CO, WILLIAMS FORK BELOW WILLIAMS FORK RESERVOIR, CO, MUDDY CREEK ABOVE ANTELOPE CREEK NR. The stage-discharge relation depends upon the shape, size, slope, and roughness of the channel at the streamgage and is different for every streamgage. In general, river discharge is computed by multiplying the area of water in a channel cross section by the average velocity of the water in that cross section: The USGS uses numerous methods and types of equipment to measure velocity and cross-sectional area, including the following current meter and Acoustic Doppler Current Profiler. The U.S. Geological Survey (USGS) started its first streamgage in 1889 on the Rio Grande River in New Mexico to help determine if there was adequate water for irrigation purposes to encourage new development and western expansion. The stage information is routinely reviewed and checked to ensure that the calculated discharge is accurate. Converting stage information to streamflow information. 4 AT USAFA, CO, RESERVOIR NO. The zero level is arbitrary, but is often close to the streambed.
Streamgages operated by the USGS provide stage measurements that are accurate to the nearest 0.01 foot or 0.2 percent of stage, whichever is greater.
The height of the surface of the water is called the stream stage or gage height. Page Last Modified: 2020-11-12 09:59:32 EST
Streamgages continuously measure stage, as stated in the "Measuring Stage"" section. TAYLOR RIVER BELOW TAYLOR PARK RESERVOIR, CO. ELK CREEK AT COAL CREEK ABV CRESTED BUTTE, CO, COAL CREEK ABV MCCORMICK DTCH AT CRESTED BUTTE, CO, EAST RIVER BELOW CEMENT CREEK NR CRESTED BUTTE, CO, SLATE R AB BAXTER GL @HWY 135 NR CRESTED BUTTE, CO, GUNNISON RIVER AT GUNNISON WHITEWATER PARK, CO, LAKE FORK BLW LAKE SAN CRISTOBAL NR LAKE CITY, CO, CIMARRON RIVER BLW SQUAW CREEK AT CIMARRON, CO, GUNNISON RIVER AT CNTY RD 32 BELOW GUNNISON, CO, COCHETOPA CREEK BELOW ROCK CREEK NEAR PARLIN, CO, ANTHRACITE CREEK ABOVE MOUTH NEAR SOMERSET. As the car or train passes, the sound of the horn seems to drop in frequency. Most of the stage and streamflow information produced by the USGS is available online in near real time through the National Water Information System (NWIS) Web. In addition, these relations must be continually checked against on-going discharge measurements because stream channels are constantly changing.
In the simplest method, a current meter turns with the flow of the river or stream. The current meter is used to measure water velocity at predetermined points (subsections) along a marked line, suspended cableway, or bridge across a river or stream. The use of ADCPs has reduced the time it takes to make a discharge measurement. In each subsection, the area is obtained by measuring the width and depth of the subsection, and the water velocity is determined using a current meter. A rating curve (fig.
At some streamgage sites, a stilling well is not feasible or is not cost effective to install. Stage at a streamgage must be measured with respect to a constant reference elevation, known as a datum.
Diagram of Channel Cross Section With Subsections. Determining discharge from stage requires defining the stage-discharge relationship by measuring discharge at a wide range of river stages. It is a two-fifths scale version of the Price AA meter and is designed to be attached to a wading rod. https://waterdata.usgs.gov/co/nwis/current?
In shallow water, the Pygmy Price current meter can be used. So basically, if a river has a high CFS that means the water is flowing faster resulting in larger rapids. Acoustic velocity meters have also been developed for making wading measurements (picture to the left).
The river-bottom tracking capability of the ADCP acoustic beams or a Global Positioning System (GPS) is used to track the progress of the ADCP across the channel and provide channel-width measurements. The ADCP has proven to be beneficial to streamgaging in several ways. We are continuing to monitor the situation for any further issues. Policies and Notices, U.S. Department of the Interior | GOAT CAMP CREEK ABV RESERVOIR NO. Subsection depth is measured using a wading rod, if conditions permit, or by suspending a sounding weight from a calibrated cable and reel system off a bridge, cableway, or boat or through a hole drilled in ice. ABV SHREWSBURY GULCH NR WESTCREEK CO, SOUTH PLATTE RIVER BLW BRUSH CRK NEAR TRUMBULL, CO, EAST PLUM CR ABV HASKINS GULCH NR CASTLE ROCK, CO, PLUM CREEK AT TITAN ROAD NEAR LOUVIERS, CO, DUTCH CR AT PLATTE CANYON DRIVE NEAR LITTLETON, CO, BIG DRY CREEK BELOW C-470 AT HIGHLANDS RANCH, CO, SOUTH PLATTE RIVER BELOW UNION AVE, AT ENGLEWOOD,C, BEAR CREEK ABOVE BEAR CREEK LAKE NEAR MORRISON, CO, TURKEY CREEK ABOVE BEAR CREEK LAKE NEAR MORRISON C, LITTLE DRY CREEK NR ARAPAHOE RD AT CENTENNIAL, CO, HARVARD GULCH AT COLORADO BLVD. NR KREMMLING, CO. PINEY RIVER BELOW PINEY LAKE, NEAR MINTURN, CO. MONTE CRISTO DIVERSION NEAR HOOSIER PASS, CO, BEMROSE-HOOSIER DIVERSION NEAR HOOSIER PASS, CO, MCCULLOUGH-SP-CRYS-DIVERSION NEAR HOOSIER PASS, CO. TENMILE CREEK BL NORTH TENMILE C, AT FRISCO, CO. STRAIGHT CR BLW LASKEY GULCH NR DILLON, CO, ELLIOTT CREEK FEEDER CANAL TO GREEN MTN RES, CO, BLUE RIVER BELOW GREEN MOUNTAIN RESERVOIR, CO. GORE CREEK AT UPPER STATION, NEAR MINTURN, CO. GORE CREEK ABV RED SANDSTONE CREEK AT VAIL, CO, EAGLE R BLW WASTEWATER TREATMENT PLANT AT AVON, CO, EAGLE RIVER BELOW MILK CREEK NEAR WOLCOTT, CO, ROARING FORK RIVER ABV LOST MAN CR NEAR ASPEN, CO, LINCOLN CREEK BELOW GRIZZLY RESERVOIR NR ASPEN, CO. ROARING FORK RIVER AB DIFFICULT C NR ASPEN, CO. HUNTER CREEK FEEDER CONDUIT NEAR ASPEN, CO, HUNTER CREEK CONDUIT BYPASS NEAR ASPEN, CO, MIDWAY CREEK FEEDER CONDUIT NEAR ASPEN, CO, MIDWAY CREEK CONDUIT BYPASS NEAR ASPEN, CO, NO NAME CREEK FEEDER CONDUIT NEAR ASPEN, CO, NO NAME CREEK CONDUIT BYPASS NEAR ASPEN, CO, ROARING FORK RIVER BLW MAROON CREEK NR ASPEN, CO, NORTH CUNNINGHAM CREEK CONDUIT BYPASS NR NORRIE,CO, CRYSTAL RIVER ABV AVALANCHE CRK, NEAR REDSTONE, CO. ROARING FORK RIVER AT GLENWOOD SPRINGS, CO. COLORADO RIVER BELOW GLENWOOD SPRINGS, CO, COLO RIVER BELOW GRAND VALLEY DIV NR PALISADE, CO, COLORADO RIVER NEAR COLORADO-UTAH STATE LINE.
The mathematical formula is: river width x depth x speed (flow and gradient) = cfs.