Answer : -- Well irrigation causes the level of the water table to go down until the subterranean flow of water eventually dries up. Shortages of water due to well irrigation are not easily perceptible.
The negative effects of well irrigation include the following:
(2) Trees, orchards and large plants don't get sufficient water so they may wither and die. Green country-side will become a desert after 30 to 45 years of intensive well irrigation.
(3) In some deep tube wells elements or minerals which are harmful to the soil get mixed with the water, causing salinity, for example. As a result the land becomes unfit for cultivation and eventually becomes infertile.
(4) When the flow of well-water stops, irrigation tanks supplied by these wells also dry up.
Thus, well irrigation should be used only as a temporary measure because of the devastating effects it can have on the surrounding environment. Alternative methods of irrigation are river irrigation, irrigation from reservoirs, shift irrigation and lift irrigation. [From 'QUESTIONS AND ANSWERS - 3', Prout in a Nutshell - Part 14, By Shrii P. R. Sarkar]
