Submersible water clarifiers

In a submersible water clarifier for use in the flowing stream, said clarifier having at least one longitudinally elongated conduit which has an upstream end and a downstream end, means for opening and closing the upstream end of each conduit, the downstream end of each conduit being opened, a settling chamber extending inwardly from the downstream end, the settling chamber having a floor toward which sediment settles and an upper portion in which clarified water accumulate in use, the improvement comprising a sediment removal passage opening through said floor, foundation means for supporting each of said elongated conduits above the bed of a stream to permit substantially uninterrupted flow of stream water below the settling chamber in the downstream direction, said sediment removal passage having a discharge orifice opening in said downstream direction through which the sediment will be extracted from the floor of said chamber by the negative pressure generated by the stream water passing by the discharge orifice in use, and outlet passage means in the upper part of each conduit through which clarified water is withdrawn.