Abstract: The invention is a water withdrawal system from a reservoir, as in a dam, for example, with a selectively adjustable withdrawal, or discharge intake, point at its core, with that intake point capable of being moved in two or three dimensions within the body of water. The invention meets the need to benefit aquatic biota by changing downstream river characteristics, such as water temperature, total dissolved gas, and mitigation of air entrainment, through obtaining the water at a specific spatial location in the upstream body of upstream water from which the downstream water is obtained, or by adjusting the characteristics of the water while it is in transit to the downstream discharge.