ABSTRACT
Flow is one of the most difficult variables to measure accurately. If we wanted to use an approximate (but very simple) method to determine open channel discharge, we would measure the velocity of a floating object moving in a straight uniform reach of the channel. If we know the cross-sectional geometry of the channel and the depth of flow is determined, we can compute the flow area. From the relationship Q=A×V, we can estimate the discharge Q. The average velocity of flow in a reach is approximated by timing the passage of the floating object along a measured length of channel.
