This paper describes the design and implementation of a model-based sonar servoing control scheme for Autonomous Underwater Vehicles (AUVs). The proposed controller is designed for autonomous surveillance of underwater structures and it is robust against external disturbances and parametric uncertainties in the AUV dynamic model. The sensor suite includes a Multi-beam Imaging Sonar which provides measurements to a RANSAC-based algorithm for structure detection and pose estimation of the vehicle with respect to the structure. The sonar-based pose estimation is properly fused with the rest of the state measurements provided by a navigation module and the resulted state vector is incorporated as feedback to the controller. The proposed control scheme has analytically guaranteed stability and convergence properties, while its applicability and performance are experimentally verified using the Nessie VI AUV in the presence of external disturbances (medium height waves).