Groundwater science is complex and many types of information are needed for comprehensive understanding. However, the most basic and important information is hydraulic head (or head). Head is the elevation of the water in a well relative to a specified horizontal surface (elevation datum) such as sea level. When head is combined with basic geologic properties such as hydraulic conductivity within the context of Darcy’s law, much can be inferred about the groundwater flow direction, and this is a starting point for investigating all types of groundwater situations. To measure head, we drill or dig a hole to the water table or, for deep groundwater systems drill a deep hole, and seal a pipe in the hole, so that water flows from the bottom portion of the pipe that is open to the groundwater system up into the solid pipe to a stable level.

This book is aimed at the development of a conceptual understanding of hydraulic head and the associated intuitive capacity for visualizing groundwater flow in one- and two-dimensional space based on head data and information about basic geologic conditions such as hydraulic conductivity. In order to facilitate development of groundwater intuition, simple schematics are used, each representing a visualized puzzle so that after studying the sequence of puzzles and the interspersed exercises of the same form, the reader is prepared to interpret head data from groundwater systems in the field. One goal is for the reader to be able to sketch diagrams as answers to many forms of “puzzles” relating head and hydraulic conductivity. This book is most effective when used in conjunction with the Groundwater-Project book Hydrogeologic Properties of Earth Materials and Principles of Groundwater Flow (Woessner and Poeter, 2020).

The senior author is a consulting hydrogeologist with broad experience and a particular interest in the design of figures to more effectively display groundwater information in multiple dimensions and who has taught contaminant hydrogeology courses at the university level.

John Cherry, The Groundwater Project Leader
Guelph, Ontario, Canada, October 2020


Conceptual and Visual Understanding of Hydraulic Head and Groundwater Flow Copyright © 2020 by Andrew J.B. Cohen and John A. Cherry. All Rights Reserved.