This paper presents a description of a finite element numerical model, BOUSS1D_iw based upon the Boussinesq equation derived by Nwogu (1993). Special attention is given to the procedure implemented into this model for wave generation, by using a source function. In order to validate BOUSS1D_iw model, two literature test cases were chosen. First the BOUSS1D_iw model (one dimensional version) is applied to the simulation of the wave propagation over a constant depth flume considering a regular wave generated in the centre of the flume, to test the source function procedure implemented into the model. After, it is applied to the experiments performed by Dingemans (1994): i.e., the wave propagation over a submerged sill, to analyze the model's performance when simulating the main phenomena involved in nearshore wave propagation, with special attention to nonlinear effects. Comparison between the BOUSS1D_iw numerical results, experimental results and results from another numerical model (Kirby et al (1998)), for time series of water surface elevation and power spectrum, are presented and discussed.