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Long-term, non-contact river velocity measurements have been made using a UHF RiverSonde system for several months at each of two locations having quite different flow characteristics. Observations were made on the Cowlitz River at Castle Rock, Washington from October 2003 to June 2004, where the unidirectional flow of the river ranged from about 1.0 to 3.5 m/s. The radar velocity was highly correlated with the stage height which was continually measured by the U. S. Geological Survey. The profile of the along-channel velocity across the water channel also compared favorably with in-situ measurements performed by the Survey. The RiverSonde was moved to Threemile Slough, in central California, in September 2004 and...
Two-dimensional river flow patterns have been measured using a pair of RiverSondes in two experiments in the Sacramento-San Joaquin River Delta system of central California during April and October 2007. An experiment was conducted at Walnut Grove, California in order to explore the use of dual RiverSondes to measure flow patterns at a location which is important in the study of juvenile fish migration. The data available during the first experiment were limited by low wind, so a second experiment was conducted at Threemile Slough where wind conditions and surface turbulence historically have resulted in abundant data. Both experiments included ADCP near-surface velocity measurements from either manned or unmanned...
Two RiverSondes were operated simultaneously in close proximity in order to provide a two-dimensional map of river surface velocity. The initial test was carried out at Threemile Slough in central California. The two radars were installed about 135 m apart on the same bank of the channel. Each radar used a 3-yagi antenna array and determined signal directions using direction finding. The slough is approximately 200 m wide, and each radar processed data out to about 300 m, with a range resolution of 15 m and an angular resolution of 1 degree. Overlapping radial vector data from the two radars were combined to produce total current vectors at a grid spacing of 10 m, with updates every 5 minutes. The river flow in...
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This data release includes the input topographic data sets, model parameters, and validation field measurements of flow velocity used to develop and test multidimensional hydraulic models for a reach of the upper Sacramento River in northern California. Digital elevation models (DEMs) were developed by combining water depth maps of the reach, created using spectrally-based remote sensing methods, with light detection and ranging (lidar) data on water surface and terrestrial elevations. The depth maps were derived from three imagery sources: (1) airborne hyperspectral imagery (CASI); (2) uncrewed aerial survey (UAS)-based hyperspectral imagery (Nano); and (3) multispectral satellite imagery (WV3). The methods used...
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The mission of the U.S. Geological Survey (USGS) involves providing reliable, impartial, and timely information that is needed to understand the Nation’s water resource. New techniques that aid in achieving this mission are important, especially those that allow USGS to do so more accurately or cost-effectively. To this end, a new method for selecting the optimum exposure time for velocity and discharge measurements has been explored. These data were assembled to assist in the development and evaluation of this new method. Four kinds of time-series data are available and used for this purpose. They are: (1) model-derived synthetic velocities, (2) point-velocity measurements in laboratory flumes, (3) point-velocity...


    map background search result map search result map Data for the development of a new method for dynamically estimating exposure time for turbulent flow measurements Digital elevation models (DEMs) and field measurements of flow velocity used to develop and test multidimensional hydrodynamic models (2D and 3D) for a reach of the upper Sacramento River in northern California Digital elevation models (DEMs) and field measurements of flow velocity used to develop and test multidimensional hydrodynamic models (2D and 3D) for a reach of the upper Sacramento River in northern California Data for the development of a new method for dynamically estimating exposure time for turbulent flow measurements