Volume of water an aquifer releases or takes into storage per unit surface area of the aquifer per unit drop of the water table is called
- Astorage coefficientCorrect
- Bspecific retention
- Cspecific yield
- Dspecific transmissivity
Solution
Concept
Definition of aquifer storage coefficient
Formula
NONE
Step-by-step solution
1. Storage properties of an aquifer quantify the volume of water released or taken into storage per unit area per unit head change. Answer: A
Explanation
The storage coefficient, or storativity, is defined as the volume of water an aquifer releases from or takes into storage per unit surface area of the aquifer per unit change in component head. In unconfined aquifers, this value is virtually equal to the specific yield. Thus, option A correctly defines this fundamental aquifer parameter.
Why the other options are wrong
B) Specific retention is the ratio of water retained against gravity to total aquifer volume. C) Specific yield is the ratio of water drained by gravity to total aquifer volume.
Shortcut
Storage coefficient = volume of water released or stored per unit area per unit decline in head.
Common mistake
Confusing storage coefficient with specific yield, which applies specifically to unconfined aquifers under gravity drainage.
Correct answer: A) storage coefficient