(1) The height of the free surface of a body of water above a given point beneath the surface. (2) The height of the water level at the headworks or an upstream point of a waterway, and the water surface at a given point downstream. (3) The height of a hydraulic grade line above the center line of a pressure pipe, at a given point.
HYDRAULIC HEAD
Meaning of HYDRAULIC HEAD in English
Environmental engineering English vocabulary. Английский словарь экологического инжиниринга. 2012