We investigated shear-induced migration of 1 micron Brownian particles in 1D, 2D, 3D steady microfluidic flows generated in straight, herringbone, and staggered herringbone channels respectively. The transverse flows induced by recessed herringbone structures in the top of the channels interplay with particle migration to the low shear regions of the pressure-driven flow. Using high-speed confocal laser scanning microscopy, we were able to image directly flowing particles inside the channels. Moreover, we located the 3D positions for each particle and obtained 2D concentration and 2D velocity profiles to better understand of the effects from the underlying flow topology, colloidal hydrodynamics, and Reynolds and Péclet number on particle migration.