<p>Spouting means is provided on the side of scum flowing wall surface within the wall surface constituting a scum intake port of scum ejecting means. The spouting means spouts pressurized water upward along the wall surface on the scum flowing side during the period from sinking of portion of the scum intake port below the surface of water to the start of flow of scum into the scum intake port. Consequently, even when aggregated scum as large as over 10 cm in thickness (diameter) is contained, the scum can be smoothly led into a pipe by means of pressurized water. Thus, the amount of water discharged by the ejection of scum can be reduced to 1/20 to 1/30 of that of conventional scum removing apparatus.</p>
