Multiple autonomous underwater vehicles (AUVs), communicating with each others in an opportunist way and through an arbitrary topology, create an ad-hoc underwater sensor network. Due to the mission in which AUVs might be employed or simply due to the drift typical of underwater scenarios, each node might be subject to movements from its initial position, leading to a variation on the network topology. In this paper, we evaluate the effect of mobility on underwater routing algorithms when any possible movement of the AUV (i.e., both voluntary and involuntary) is taken into account. Namely, we assume that the movement of each AUV might be due to either an involuntary drift or a voluntary movement to accomplish a given mission. Results depict the impact of mobility on the system performance, considering both location dependent and independent applications.