RiverSurveyor How-to | The Loop Method

In this short video illustration, you will learn the basics of how to conduct a Loop Method measurement, considered an industry standard, and accepted by topwater monitoring agencies worldwide.

The Loop Method is used to correct discharge measurements that are biased by sediment transport (moving-bed) when bottom-tracking is used as a reference to measure boat speed. The basic premise is based on a “back and forth crossing closure error” where the apparent upstream movement of the ship-track is used along with the measurement time to determine the mean velocity of a moving bed. In the case with a moving bed, the discharge will be biased LOW by a certain percentage based on the velocity magnitude of the moving-bed but can be corrected using the Loop measurement.

Another way to avoid moving bed bias is to use the Stationary Method, and the new RS 4.0 includes big improvements to RiverSurveyor Stationary Live software.

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