Author(s): Daniel Wagenaar, Xue Fan
Linked Author(s): Daniel Wagenaar
Keywords: Acoustic, velocity, sediment, bathymetric, watercube
Abstract: The application of acoustic doppler instruments has expanded into various facets of catchment hydrology and water engineering and this paper will demonstrate the successful integration of the technology within existing practices in determining suspended-sediment concentration. The traditional methodology that is applied over the past century in defining these key parameters has number of limitations due to the available technology and resources required to perform field measurements and often resulted in insufficient and unreliable data sets for model development and yield calculations. Research is done by the USGS and U. S. Army Corps of Engineers to identify the most effective surrogate for suspended-sediment concentration (SSC). The methodologies that are identified for the study consist of turbidity, laser diffraction and acoustic backscatter principles. During the initial investigation, it is found that the most promising technique is the measurement of acoustic backscatter strength with an acoustic doppler velocity meter (ADVM). A surrogate model is developed based on the SSC samples taken over a two year period in both the Clearwater and Snake Rivers from 2008 -2010. ADVM measurements are performed during the same period and the acoustic backscatter surrogate displays the best relation with the measured SSC during the development of the model. The acoustic surrogate model provides improved estimation of SSC and load than the traditional sediment-transport curves based on discharge during different time scales when sediment concentration is variable (Wood and Teasdale, 2013). The acoustic doppler velocity meters (ADVM) demonstrates during the acoustic surrogate model development the robustness of the technology. The study results also highlight that a higher frequency instrument shows the best estimation of SSC of all technologies. The application of acoustic doppler technology in catchment hydrology is becoming an important criteria in the application science in the various spheres of hydrology
Year: 2017