Evaluation of ADCP apparent bed load velocity in a large sand-bed river: Moving versus stationary boat conditions

Journal of Hydraulic Engineering
By: , and 

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Abstract

Detailed mapping of bathymetry and apparent bed load velocity using a boat-mounted acoustic Doppler current profiler (ADCP) was carried out along a 388-m section of the lower Missouri River near Columbia, Missouri. Sampling transects (moving boat) were completed at 5- and 20-m spacing along the study section. Stationary (fixed-boat) measurements were made by maintaining constant boat position over a target point where the position of the boat did not deviate more than 3 m in any direction. For each transect and stationary measurement, apparent bed load velocity (vb) was estimated using ADCP bottom tracking data and high precision real-time kinematic (RTK) global positioning system (GPS). The principal objectives of this research are to (1) determine whether boat motion introduces a bias in apparent bed load velocity measurements; and (2) evaluate the reliability of ADCP bed velocity measurements for a range of sediment transport environments. Results indicate that both high transport (vb>0.6 m/s) and moving-boat conditions (for both high and low transport environments) increase the relative variability in estimates of mean bed velocity. Despite this, the spatially dense single-transect measurements were capable of producing detailed bed velocity maps that correspond closely with the expected pattern of sediment transport over large dunes. ?? 2011 American Society of Civil Engineers.

Additional publication details

Publication type Article
Publication Subtype Journal Article
Title Evaluation of ADCP apparent bed load velocity in a large sand-bed river: Moving versus stationary boat conditions
Series title Journal of Hydraulic Engineering
DOI 10.1061/(ASCE)HY.1943-7900.0000373
Volume 137
Issue 9
Year Published 2011
Language English
Larger Work Type Article
Larger Work Subtype Journal Article
Larger Work Title Journal of Hydraulic Engineering
First page 1064
Last page 1071