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Moving-boat Measurements

Moving-boat deployments include crewed boats, tethered boats, and remote-control boats.

Acoustic Doppler Current Profilers (ADCPs) are commonly deployed on moving boats to measure velocity distributions and discharge in oceans, estuaries, rivers, and streams. The velocity measured by a boat-mounted ADCP is the velocity of the water relative to the instrument (relative velocity). The velocity of the boat must be measured and removed from the relative velocity to obtain the actual water velocity. ADCPs designed for use on moving boats are able to measure the velocity of the boat using bottom tracking. At sites with significant sediment transport it is possible that bottom tracking will be biased by a moving-bed condition. If a moving-bed condition exists, the boat velocity must be measured with GPS or the measured velocities and discharge must be corrected (loop method, mid-section method, multiple stationary moving-bed tests) to remove the bias.

Moving-boat Deployment Resources

Guidance: Published guidance reports, technical memorandums, and recommended procedures.

Software: USGS utilities and post-processing programs, public domain software, manufacturer's firmware and software.

Deployments: A summary of mounts, tethered boats, RC boats, manned boats, and wireless communications.

Tech Tips: Tips for using your ADCP or deployment platform.

References: Reference manuals, relevant publications, hydroacoustic updates, forms, and select presentations.

Velocity Mapping: Links to sample applications, discussion of potential problems, summary of relevant equations, and links to processing software.