Experimental investigation and one-dimensional (1D) dynamic modelling of steady flow through a levee breach

Abstract

Accurate prediction of levee breach flow is crucial to the mitigation of floods, and for timely breach closure. In this work, flow in an idealized levee breach has been studied for the case of a trapezoidal embankment. Flow data including water depths, surface velocities, and flow discharges were obtained from 28 experiments considering different cases of breach width and main channel downstream water depth. Ultrasonic sensors were used to record the water depth in the channel and the breach. The water surface velocity was measured using a particle tracking velocity method. A one-dimensional dynamic model based on the conservation of mass and momentum in two control volumes was developed by drawing similarities between levee breach flows and diverging open channel junction flows. The proposed model shows satisfactory performance against two independent datasets.