A potentiometric surface is the imaginary plane where a given

reservoir A reservoir (; from French ''réservoir'' ) is an enlarged lake behind a dam. Such a dam may be either artificial, built to store fresh water or it may be a natural formation. Reservoirs can be created in a number of ways, including contro ...

of fluid will "equalize out to" if allowed to flow. A potentiometric surface is based on

hydraulic Hydraulics (from Greek: Υδραυλική) is a technology and applied science using engineering, chemistry, and other sciences involving the mechanical properties and use of liquids. At a very basic level, hydraulics is the liquid counter ...

principles. For example, two connected storage tanks with one full and one empty will gradually fill/drain to the same level. This is because of atmospheric pressure and gravity. This idea is heavily used in city water supplies - a tall

water tower A water tower is an elevated structure supporting a water tank constructed at a height sufficient to pressurize a water distribution system, distribution system for potable water, and to provide emergency storage for fire protection. Water towe ...

containing the

water supply Water supply is the provision of water by public utilities, commercial organisations, community endeavors or by individuals, usually via a system of pumps and pipes. Public water supply systems are crucial to properly functioning societies. Thes ...

has a great enough potentiometric surface to provide flowing water at a decent pressure to the houses it supplies. For

groundwater Groundwater is the water present beneath Earth's surface in rock and soil pore spaces and in the fractures of rock formations. About 30 percent of all readily available freshwater in the world is groundwater. A unit of rock or an unconsolidate ...

"potentiometric surface" is a synonym of "piezometric surface" which is an imaginary surface that defines the level to which water in a

confined aquifer An aquifer is an underground layer of water-bearing, permeable rock, rock fractures, or unconsolidated materials (gravel, sand, or silt). Groundwater from aquifers can be extracted using a water well. Aquifers vary greatly in their characterist ...

would rise were it completely pierced with

wells Wells most commonly refers to: * Wells, Somerset, a cathedral city in Somerset, England * Well, an excavation or structure created in the ground * Wells (name) Wells may also refer to: Places Canada *Wells, British Columbia England * Wells ...

. If the potentiometric surface lies above the ground surface, a flowing

artesian well An artesian aquifer is a confined aquifer containing groundwater under positive pressure. An artesian aquifer has trapped water, surrounded by layers of impermeable rock or clay, which apply positive pressure to the water contained within th ...

results.

Contour maps A contour line (also isoline, isopleth, or isarithm) of a function of two variables is a curve along which the function has a constant value, so that the curve joins points of equal value. It is a plane section of the three-dimensional graph ...

and profiles of the potentiometric surface can be prepared from the well data.

References

* ''Earth: Portrait of a Planet; Second edition''; Stephen Marshak, 2005 W.W. Norton & Company, Inc (Page 604–605) Concepts in physics Dynamics (mechanics) Effects of gravitation {{Watersupply-stub

See also

References