Towards a continuous monitoring method of water and sediment discharge in the Mahakam river and distributary channels
Maximiliano Sassi, Bart Vermeulen, Hidayat Hidayat, Ton Hoitink
Thursday 2 july 2015
12:00 - 12:15h
at Africa (level 0)
Themes: (T) Special session, (ST) Acoustic monitoring of flow, turbulence and river discharge
Parallel session: 11F. Special session: Acoustic monitoring of flow, turbulence and river discharge
Water discharge can be continuously monitored with horizontally deployed acoustic Doppler current profilers (H-ADCPs). H-ADCPs may be used to continuously monitor suspended sediment discharge provided the H-ADCP backscatter signal is transformed to sediment concentration. We explore the ability of H-ADCPs to continuously monitor sediment discharge when combined with repeated surveys with a ship-mounted ADCP. Continuous, fixed station measurements of flow velocity and turbidity were taken with an H-ADCP and an optical backscatter sensor (OBS) in the Mahakam river. At several locations, we collected simultaneous vertical profile measurements with an ADCP, an OBS and a Laser In Situ Scattering and Transmissometer (LISST). Mass concentration from one hundred water samples allowed us to investigate the backscatter response to variation in concentration and in particle size distributions. We introduce a generic calibration approach to quantify sediment discharge in the Mahakam river and bifurcating branches of its delta.
