“…Following the ground-breaking papers of Constantin and Strauss [3,12], the study of rotational water flows with a fixed mass-flux received significant attention-evidentiated by an abundance of works on issues like symmetry [1,2,5,33,52], stability [6], regularity [11,13,21,22,24,25], stratification [20,27,30,32,34,59,60], the presence of stagnation points and critical layers [13,17,19,20,48,53,58]-much less has been done in the scenario of the fixed mean-depth. The fixedness of the meandepth is a perspective, of physical relevance, proposed by Henry, cf.…”