Author(s): David Reungoat, Xinqian Leng, Hubert Chanson
Linked Author(s): Hubert Chanson
Keywords: Tidal bores, field measurements, suspended sediment processes, channel siltation, Garonne River
Abstract: A tidal bore is a hydraulic jump in translation propagating upstream in an estuarine channel when a macro-tidal flood tide enters a funnel shaped river mouth with shallow waters. The tidal bore of the Garonne River (France) was extensively investigated in the Arcins channel in 2015, focusing on the temporal evolution of hydrodynamics and sediment processes during spring tide period. The tidal bore had a marked effect on the velocity field, including a rapid flow deceleration and flow reversal. Maximum flow deceleration between -0. 65 m/s2 to almost -1. 4 m/s2 were observed. The early flood flow motion was very energetic with large fluctuations in all velocity components. The suspended sediment concentration (SSC) data showed very large instantaneous SSC levels, in excess of 100 kg/m3, during the passage of the tidal bore front, as well as large SSCs during the first hour of the flood tide for the entire observations. The work culminates a 5-year research project at the same site, showing a progressive siltation of the Arcins channel during the last three years
Year: 2017