The rate of discharge of water from the well divided by the drawdown of the water level within the well.
The rate of discharge of groundwater per unit area of a porous medium measured at right angle to the direction of flow.
The rate of flow of water through a unit cross-sectional area under a unit hydraulic gradient at the prevailing temperature (field permeability coefficient) or adjusted to a temperature of 150C (60-F).
The observed permeability of a porous medium to one fluid phase under conditions of physical interaction between this phase and other fluid phases present.
A measure of the relative ease with which a porous medium can transmit a fluid under a potential gradient and is a property of the medium alone (after Lohman and others, 1972). The property of a porous medium itself that expresses the ease with which gases, liquids, or other substances can pass through it.
The permeability measured when the rock contains only one fluid.