The static and dynamical properties of one-dimensional water chains confined in zeolitic channels are studied by means of the Car Parrinello method. The properties of such an unusual water structure, present in zeolites Li-ABW and bikitaite, are reported and compared. Differences in the zeolitic frameworks are responsible for the different properties of the water chains. A more rigid chain structure is found in bikitaite, whereas our calculations predict that in Li-ABW water molecules are allowed some rotational degrees of freedom. We interpret such a finding on the basis of the different strengths of host-guest, dipolar interactions. Weaker interactions in Li-ABW allow for rotation of water molecules.