Abstract
A video image analysis method for the velocity distribution measurement of the flood flow in a river was developed. Water surface images taken from the tall building facing to the river was used for the Particle Image Velocimetry by use of a personal computer. The accuracy of the velocity measurement was found to be dependent on the angle between a video camera and water surface by laboratory study. The field application was successfully made to the flood flow in the Yodo River in July, 1993; the discharge of the flood peak was well estimated; and the result was also examined by the 2-D numerical simulation in BFC.
