As the current main source of continental fresh water discharge in the Mediterranean Sea, the Rhone River inputs are a key forcing for ecosystems of the Gulf of Lions in the western basin. In order to better characterize the exchanges at this key interface, an oceanographic buoy has been installed at the Rhone River mouth in June 2009 for high frequency multiparameter measurements with bottom, water column and air sensors. Data are sent in near real time towards an onshore data center.