The openFOAM solver faDebrisFOAM was recently developed to simulate debris flows with the finite area method. This new solver includes, among other capabilities, a variable density for the solid-liquid mixture, erosion and deposition processes, and a terrain modification algorithm. To test the performance of this new solver, we simulate the debris flow event that occurred in the Crucecita alluvial fan on the 13th May 2017 in the Atacama Desert, Chile. Thanks to pre- and post-event topographies, we have an accurate measure of the morphological changes that took place. Comparing the field data and our numerical model results shows that faDebrisFOAM can reproduce the main flooded, eroded, and deposited areas. Once the model is calibrated, we study the behavior of the terrain modification algorithm. Finally, we discuss the advantages of using this model to reproduce erosion and deposition processes together with changing rheologies for a debris flow event.