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USGS · 70022280

Measuring stream discharge by non-contact methods: A proof-of-concept experiment

Abstract

This report describes an experiment to make a completely non-contact open-channel discharge measurement. A van-mounted, pulsed doppler (10GHz) radar collected surface-velocity data across the 183-m wide Skagit River, Washington at a USGS streamgaging station using Bragg scattering from short waves produced by turbulent boils on the surface of the river. Surface velocities were converted to mean velocities for 25 sub-sections by assuming a normal open-channel velocity profile (surface velocity times 0.85). Channel cross-sectional area was measured using a 100 MHz ground-penetrating radar antenna suspended from a cableway car over the river. Seven acoustic doppler current profiler discharge measurements and a conventional current-meter discharge measurement were also made. Three non-contact discharge measurements completed in about a 1-hour period were within 1 % of the gaging station rating curve discharge values. With further refinements, it is thought that open-channel flow can be measured reliably by non-contact methods.

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BibTeXRIS

J. E. Costa, K.R. Spicer, R. T. Cheng, F.P. Haeni, N.B. Melcher, E.M. Thurman, W.J. Plant, W.C. Keller. 2000-02-15. Measuring stream discharge by non-contact methods: A proof-of-concept experiment. https://doi.org/10.1029/1999gl006087

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