Parshall flume is one of many available tools for the measurement of discharge in open channels. One of the most extensively used in Taoyuan irrigation area is the Parshall flume. In this study an attempt is made to review and investigate the most widely used method for the measurement of discharge in Taoyuan irrigation area. The depth-discharge relationships of Parshall flume of various sizes, as calibrated empirical, represented by some specific equations,are applicable in many practical problems. It is desirable to measure the depth-discharge relationships of Parshall flume repeatedly, so that the accuracy of the relationships will be derived. However, the Parshall flume will become invalid, because deposition of the debris and inadequate circumstances will produce undependable results. We finally also derive the checkout table to review and check Parshall flume circumstances in practical.
