A number of industries, the water industry being an obvious example, need advanced capabilities of flow measurement in order to monitor pollution levels. Watercourses (whether they be rivers, canals, sewers outfalls) exhibit complicated flow patterns, and it is also often critical that any changes to the flow can be monitored as they happen. An ideal flow measurement system therefore would operate in real time, and give the user as detailed a description as possible of the flow patterns of the target system. It is the purpose of this project to develop a sensor which will meet these requirements. If a system sends a single acoustic pulse perpendicular to the direction of flow, and monitors the echo it is possible, using the principle of the Doppler effect, to produce a real time single axis flow profile. In addition, by monitoring the backscattering of the signal it is feasible to produce a measure of sediment in the water.