Abstract: Hydraulic ram pump apparatus is provided, of the type including a body member (7) having a water flow passage therethrough, a waste gate (1) disposed in the passage, a delivery outlet (23) and a one-way delivery valve (10, 11) disposed in the outlet. The improvement therein lies in the waste gate (1) being pivotally mounted to the body member (7) and configured such that, in its fully open position (1a), the waste gate (1) does not significantly restrict the flow of water through said passage, in the interest of efficiency at low drive heads. The waste gate (1) is spring biased towards its open position to provide opening assistance to the waste gate (1) at low drive heads. The spring bias is such that it is at its greatest when the waste gate (1) is fully closed and is substantially zero when the waste gate is fully open.

Abstract: Hydraulic ram pump apparatus is provided, of the type including a body member (7) having a water flow passage therethrough, a waste gate (1) disposed in the passage, a delivery outlet (23) and a one-way delivery valve (10, 11) disposed in the outlet. The improvement therein lies in the waste gate (1) being pivotally mounted to the body member (7) and configured such that, in its fully open position (1a), the waste gate (1) does not significantly restrict the flow of water through said passage, in the interest of efficiency at low drive heads. The waste gate (1) is spring biased towards its open position to provide opening assistance to the waste gate (1) at low drive heads. The spring bias is such that it is at its greatest when the waste gate (1) is fully closed and is substantially zero when the waste gate is fully open.