Weirs are the common and important structures which are used in controlling and
measuring the flow in irrigation channel. This study carried out experimental runs to
survey the velocity distributions in each vertical and longitudinal directions,
downstream compound weirs. It uses compound sharp-crested weirs consisting of two
triangular parts with different weir angles. All parameters, such as head over the weir,
h, downstream water depth, ytail, bed type, and the shape of the compound weir, which
affect the velocity distribution were studied. Three weirs, 90/90, 90/120, and 90/150,
two beds, sand and plastic, four heads, 6, 9, 12, and 15 cm, and three downstream
depths, 10, 14, and 18 cm were used. The results show that the vertical and longitudinal
velocity distributions increase with water head and with plastic bed case. The velocity
distributions decrease for larger wide weir and higher downstream water depth.