Measurement of Velocity and Discharge of a Stream Using a New Floating Rod Equipped with a GPS Receiver

It is quite difficult and risk-taking to directly measure velocity and discharge of the streams during rapidly changing floods under nasty weather. Traditionally, floating rod method as well as indirect method is used in this situation. Though safe, floating rod method is regarded as relatively less accurate. We developed a new floating rod equipped with an integrated module composed of a GPS receiver and a RF transceiver on the head, which can measure flood velocity by tracking its position. Furthermore, simultaneous deployment of up to fifteen floats provides longitudinal velocity of streamlines along which they pass. Discharge is instantaneously calculated by combination of measured velocities and pre-surveyed cross-section area data for every deployment of floating rods. Some application examples show measured velocity and a 2D flow vector plot, and discharges calculated with this floating rods system indicate fairly good agreement with reference discharges like dam release and rated discharge.