A system an oil-water separation system including a vessel for receiving an oil-water mixture and passing a treated water having a lower concentration of oil than the oil-water mixture. The system further includes a first overflow baffle for directing the oil-water mixture fluid flow over the first overflow baffle, and a first underflow baffle positioned downstream along a fluid flow pathway of the first overflow baffle for directing the oil-water mixture fluid flow under the first underflow baffle, and a second overflow baffle positioned downstream along the fluid flow pathway of the first underflow baffle having a mesh with a plurality of perforations which directs fluid flow over the second overflow baffle and through the plurality of perforations. The second overflow baffle permits a water portion of the oil-water mixture to traverse through the mesh and an oil portion of the oil-water mixture to traverse over the mesh.