ABSTRACT
In this study, acoustic backscatter profiles obtained from a 600 kHz, side-looking acoustic Doppler current profiler (ADCP) were used to estimate optical turbidity derived estimates of suspended sediment concentrations in Georgiana Slough in California’s Sacramento-San Joaquin Delta. The backscatter profiles were corrected for both fluid and sediment acoustic attenuation. The sediment attenuation coefficient was determined empirically from the slope of the fluid-corrected acoustic backscatter profiles. This approach requires knowledge of only the frequency of the ADCP, water temperature and the salinity of the water. The corrected backscatter profiles were compared to computed suspended sediment concentrations (SSC) derived from optical turbidity sensor output over about 40 days, including two events with concentrations ranging from 30 to 220 mg/l (data are provisional and subject to revision). Root Mean Square (RMS) error between acoustically estimated SSC and SSC computed from optically measured turbidity was calculated as ~25 mg/l with a coefficient of determination R 2 = 0.87.
