Abstract This study extends an energy-balance-equation wave model (a phase-averaging wave model) for multidirectional random wave transformations to account for wave shoaling, refraction, diffraction, reflection and breaking. Quadratic upstream interpolation for convective kinematics is used in the discretization to reduce numerical diffusion. Predictions using the present wave model are compared with Sommerfeld's solutions for wave transformation through a gap between breakwaters, experimental observations for wave transformation due to a circular shoal, and field measurements for waves behind a breakwater. The results of these comparisons show fairly good agreement.