We seek to assess the impact of underwater sand mining activity on beaches located near the extraction area.  Beach profiles measured on the beaches of interest are used as indicators. Baseline beach profiles were obtained in 2006. Beach profiles for comparison purposes were obtained in 2010. We used the concept of equilibrium profile to assess the changes found. At Mogo Mogo Island there was evidence of a significant deficit of sand. This can be explained if we consider that the area of underwater sand mining gave this beach a natural defense from waves that come from the southeast.