The three dimensional near wake flow topology behind a blunt trailing edge flat plate isinvestigated for a Reynolds number range varying from 500 to 4.6x104 using a combination offlow visualization, numerical simulations and experiments. The secondary wake instabilities areidentified using vorticity maps from CFD and performing Proper Orthogonal Decomposition(POD) on PIV data from experiments to identify the underlying dominant coherent structures.These structures are found to appear at a spanwise spacing ranging from 2.2 to 4.8. At higherReynolds numbers the secondary wake instabilities appear to be unsteady in space and time.