Tubewells are large accumulations of water found deep inside the earth (over 15 mts) and are drawn out by digging a deep boring and taking out the water with the help of an electric or diesel motor.
Conditions required for the construction of a Tubewell
1. A large amount of underground water should be available
2. There should be regular supply and cheap electricity
3. Good fertile land should be available so that the cost of construction and electricity can be compensated
Merits of Tubewells
1. Tubewells are deep and so they are useful in the dry period
2. These can irrigate a larger area and the water is not polluted
3. Large amounts of water can be pulled out in a short while
4. No manual labour is required
5. Tubewells can be used only when required and the amount of water can be regulated
Demerits of Tubewells
1. Tubewells can irrigate a much smaller area than other means of irrigation
2. This means cannot be used in areas where underground water is brackish
3. There is a regular expenditure on electricity or diesel
4. There is depletion of underground water
5. It can only be constructed in areas where the soil is soft for digging
Important Areas
Mainly used in the northern states of Punjab, Haryana, Uttar Pradesh and Bihar.