Question

The clogging of well screens and consequent reduction in pump efficiency is indicated by _____________

(a) the high value of the well-loss

(b) the low value of the well-loss

(c) variable value of the well-loss

(d) both high and low value of the well-loss

This question was addressed to me in an internship interview.

The origin of the question is Aquifers and Their Type-2 topic in portion Ground Water for Irrigation through Wells and Tubewells of Irrigation Engineering

Answer 1

The correct answer is (a) the high value of the well-loss

Easiest explanation: When the screen size is compatible to the surrounding porous media, the well loss is caused by the axial movement inside the well up to the pump intake (since the well loss through the screen is very small). When clogging of the screen increases, the well loss increases which adversely affects the pump efficiency.