Drawdown

The lowering of the water level of a reservoir as a result of withdrawing water.

The distance that the water surface of the reservoir is lowered from the normal full elevation to the lowest allowable elevation as the result of the withdrawal of water for the purposes of generating electricity.

The differential pressure in a constant-rate producing well between the static (shut-in) bottomhole pressure and the flowing bottomhole pressure. The location of this pressure condition is generally found within the wellbore directly across the completion interval.