For a Cutthroat flume operating under free-flow conditions, where the resistance in the downstream channel doesn’t flow or restrict flow out of the flume, it's easy to calculate the flow rate.
At the primary point of measurement, Ha, simply take a yard stick (or use a staff gauge) to determine the depth of water from the floor of the flume to the water’s surface. Then just take this reading and enter it into the flow equation.
As with other short-throated flumes, the Cutthroat has a single primary point of measurement, located upstream of the throat of the flume a distance of 2L/9, where L = flume length. The distance is measured along the center line of the flume. The location (2L/9) is true for all, with the correct locations indicated on the Cutthroat flume master dimensions drawing.
