Research on seismic protection of buildings and infrastructures recently focused on so-called seismic metamaterials as very promising concept. In a broad sense, the term metamaterial denotes an engineered material with exotic properties not obtainable in natural materials, which arise from a tailored design of its architecture. In the last few years, various metamaterials were conceived for elastic wave control and manipulation and, in this context, a growing number of studies was devoted to a generalization for seismic applications. Among others, some studies formulated the concept of metabarrier, which consists in modifying the properties of the soil surrounding the structure to be protected by appropriate structuring. This work investigates the elastic wave propagation of seismic surface waves through periodic water-tank metabarriers. The dispersion properties of the infinite metabarrier are investigated by means of the Bloch-Floquet theory for different dimensions and cross-section geometries of the unit tank. The surface wave modes are identified by introducing the sound cone and making use of a pertinent energy parameter [1,2]. Next, dynamic analyses of a finite metabarrier are carried out in frequency and time domains, validating the proposed concept.