This paper proposes a lattice Boltzmann scheme to simulate two-dimensional fluid transients. A set of multi-scale equations, which characterize the relations between the lattice Boltzmann equation and its corresponding macroscopic equations, were derived by using the Chapman-Enskog expansion. Based on these multi-scale equations and the basic equations of multidimensional fluid transients, two special lattice Boltzmann models were established. Numerical simulation of one-dimensional pressure wave transmission and reflection, two-dimensional wave corner diffraction and hydraulic transients in a concrete spiral case show that the Lattice Boltzmann Method (LBM) is a feasible and promising approach to simulate multidimensional transient flows.