Performance of Non-Contact Flow Meters in Irrigation Canals and Surface Drains

Flow measurement is an important component of modern irrigation delivery systems. As irrigation projects are modernized, flow measurement devices are being installed in more non-traditional applications. Some applications feature a combination of characteristics that eliminate traditional flow measurement structures. Furthermore, as regulations obligate more districts to report real time diversions, redundant flow measurement devices using different methods or technologies become necessary to reduce the potential for temporary gaps in diversion data. In these cases, non-contact type flow measurement devices may be of interest. Two non-contact flow meters were installed at different irrigation district canals. Data was collected from the non-contact meters as well as a pre-existing flow measurement device operating in parallel. In addition, intermittent current metering was conducted at each site and used as the standard for calibration purposes. This paper presents an analysis of the flow measurement data collected and a discussion of the non-contact meter performance in open channel irrigation system applications