Editing Well test (section)

==Specific capacity==
'''Specific capacity''' is a quantity that which a [[water well]] can produce per unit of drawdown. It is normally obtained from a step drawdown test. Specific capacity is expressed as:
:<math>S_c=\frac{Q}{h_0 - h}</math>
where
:<math>S_c</math> is the specific capacity ([L<sup>2</sup>T<sup>−1</sup>]; m²/day or USgal/day/ft)
:<math>Q</math> is the pumping rate ([L<sup>3</sup>T<sup>−1</sup>]; m³/day or USgal/day), and
:<math>h_0 - h</math> is the drawdown ([L]; m or ft)
The specific capacity of a well is also a function of the pumping rate it is determined at.  Due to non-linear well losses the specific capacity will decrease with higher pumping rates.  This complication makes the absolute value of specific capacity of little use; though it is useful for comparing the efficiency of the same well through time (e.g., to see if the well requires rehabilitation).