Question

What is the volume of groundwater which can be extracted by gravity drainage from a soil stratum when expressed as percentage fraction of the volume of the soil stratum?

(a) Pellicular water

(b) Available water

(c) Specific yield

(d) Field capacity

This question was posed to me in quiz.

This interesting question is from Aquifers and Their Type-1 in chapter Ground Water for Irrigation through Wells and Tubewells of Irrigation Engineering

Answer 1

The correct option is (c) Specific yield

The explanation is: Yield is the volume of groundwater extracted by gravity drainage from a saturated water-bearing material. It is known as the specific yield when it is expressed as the ratio of the volume of the total material drained.

Specific Yield = (Volume of the water obtained by gravity drainage/ total volume of drained material) x 100.