  We introduce hydrodynamics derived from the action of a perfect fluid
deformed by the Wess-Zumono-Novikov multivalued functional generated by
combined actions of gauge transformations and spacetime diffeomorphisms. The
deformation is structured analogously to the Wess-Zumino functional, commonly
used as an effective description of field theories with the chiral anomaly and
produces consistent fluid equations which are covariant under spacetime
diffeomorphisms and Onsager semiclassical quantization. The deformation affects
the continuity equation giving fluid spin degrees of freedom.
