Abstract: A vacuum system for transmitting intermittently injected sewage including a collection tank fed by a gravity operated sewage pipe for holding sewage at atmospheric pressure. The sewage is intermittently injected into a vacuum line under the influence of atmospheric pressure when a sewage injection valve is opened. The vacuum sewage line is connected between the injection valve and a vacuum collection tank, the vacuum collection tank having a source of vacuum pressure applied thereto. A vacuum line section is laid out in a sawtooth fashion, having a riser, a low point, and a downslope. When no sewage is being transported through the vacuum conduit, the sewage remaining in the conduit collects in the low point. The low point does not completely fill with sewage so that vacuum pressure is communicated throughout the vacuum line. When the sewage injection valve is opened, the sewage going through the vacuum line forms a hollow cylindrical mass which sweeps toward the vacuum collection tank.