Assessing discharge measurement errors at a gauging station in a small catchment (Vallcebre, Eastern Pyrenees)

Discharge is measured in a gauging station controlled by a two levels rectangular notch weir with two different widths and contraction conditions that ensure a unique relationship between stage and discharge (Fig. 1 and Fig 2). The structure, designed to flush sediment, enables to capture a wide range of discharge. Water level is measured using a pressure sensor located in the middle of the gauging station, 3.4 m upstream the control reach. Sediment concentration is measured using two automatic samplers. Turbidity is measured using two types of sensors: an Optical Backscatter Sensor (OBS) and an ultrasound sensor. Assessing discharge measurement errors at a gauging station in a small catchment (Vallcebre, Eastern Pyrenees) G. Nord (1), J.P. Martin-Vide (2), J. Latron (1), M. Soler (1), and F. Gallart (1)