Accuracy of discharge measurements in a vegetated river

Hydraulic measurements are necessary to calibrate numerical models and to collect information about the situation under field and laboratory conditions. The accuracy of the measurements depends on several factors.Laboratory research is carried out to evaluate the accuracy of different techniques and methods under well-controlled conditions. Field measurements are performed to evaluate the impact of natural conditions on the accuracy of the measurements.The better the quality of the discharge measurements, the more possible is the reliable determination of the roughness coefficient, leading to an improved accuracy of hydraulic modelling.Several measurement techniques and instruments (as hydrometric propellers and electromagnetic devices) are discussed in this paper. Furthermore, the possibility of continuous measurements is researched, next to the influence of the macrophytes on discharge measurement in vegetated rivers.