Use of Tube wells in Rural India

Remote villages in India have limited access to portable water resources. The villagers rely heavily on surface water like rivers, ponds or lakes for daily ablutions, washing clothes, cooking, etc. In the absence of adequate sources of surface water, a majority of them are forced to depend on tube wells. A long metal tube is drilled into the ground until it reaches the underground aquifer. Water is then pumped up, traditionally by manual effort. In drier regions that do not receive sufficient rainfall and lack irrigation facilities, tube wells are often attached to motor pumps, which are operated by electricity. The pumped-up water is used for watering the fields and for cultivation. The introduction of electric pumps is a more recent phenomenon that has spread to the relatively affluent villages in India.

Depleting Water Table

There are over 21 million tube wells in India. The widespread and often indiscriminate use of this pumping device has led to depletion of the water table, as ground water is being extracted much faster than it can be replenished by rainfall. "Every year, farmers bring another million wells into service, most of them outside the control of the state irrigation authorities. The pumps, powered by heavily subsidized electricity, work day and night to irrigate fields of thirsty crops like rice, sugar cane and alfalfa. But this massive, unregulated expansion of pumps and wells is threatening to suck India dry. "Nobody knows where the tube wells are or who owns them. There is no way anyone can control what happens to them," says Tushaar Shah, head of the International Water Management Institute's groundwater station, based in Gujarat. "When the balloon bursts, untold anarchy will be the lot of rural India," he says.""¹ Most of the irrigation projects in India have a low operation efficiency in the range 30–40%, and lose approximately 60–70% of irrigation water during conveyance and application. ²

An Alternative: Horizontal Tube wells

A new experiment of digging sideways, instead of digging down, is being conducted in South India. At present, digging such horizontal tube wells (locally called 'adda bores') is only viable where there are no hard rocks, and where there is enough soil moisture to indicate the presence of water nearby. The cost of constructing a horizontal tubewell is comparatively cheaper because there is no need to invest in submersible motors used to operate vertical tubewells. "Since horizontal bore wells usually draw water only from the top layer of the soil, they will attract water from the neighboring one acre area or so. If one adopts groundwater recharge measures in the catchment area, adda bores will last long, just like open wells." ³