Science in Practice Portal

Stream discharge measurement with a Price AA current meter and wading rod, using U.S. Geological Survey techniques, is a time consuming process. This paper describes a measurement methodology for small streams, with less than ideal measuring conditions, that reduces process time by 35-50 percent. Accuracy of current-meter flow measurements, as compared to Parshall flume measurements, range from eight percent at a flow rate of 1 ft3 /sec to about three percent at 10 ft-vsec. At flows approaching 100 ft3/sec, differences will be about 1%. Reproducibility of current-meter flow measurements is within three percent.