the vortex channel base 25 have a supercritical slope of about ten percent as noted while the embodiment shown in fig1 and 2 illustrate a vortex form containing an entrance flume 22 other embodiments of the present invention may fluidly connect the vortex channel 24 directly to the influent line 12 omitting the use of the entrance flume 22 examples of such embodiments are shown in fig3 4 and 5 referring to fig2 the vortex channel 24 directs the sewage flow into a substantially spiral flow the vortex channel 24 also reduces the radius of this spiral flow in order to increase the centripetal forces acting upon the flow this is accomplished through the reduction in radius of the outer wall 26 which will increase the centripetal forces applied by the outer wall 26 on the spiral flow in the embodiment shown in fig2 a radius transition section 28 supports the outer wall 26 and reduces the radius of the spiral flow created by the vortex channel 24 shown in fig2 as r 1 to the radius of the conduit 40 shown as r 2 the radius transition section 28 also aids in directing the flow from the vortex channel 24 into the conduit 40 the radius transition section 28 is generally made of a noncorrosive metal or plastic with concrete or a foam fill material to allow the sewage flow to enter the conduit 40 inner wall 27 must include a height transition section 29 identified on fig2 4 and 6 as section a b which allows the sewage flow to enter the conduit 40 it is envisioned that this.