Water is indispensable to agricultural production. In areas where rainfall is plentiful and well distributed over the year, there is no problem of water. But rainfall in certain areas in very scanty as well as incertain.
This is so in Deccan and central India. Punjab and Rajasthan, in this areas, artificial irrigation is absolutely essential for without it cultivation is almost impossible. There are certain food and cash crops such as rice and sugarcane, which require abundant, regular and continuous supply of water.
During the 50 years since Independence, the Government had spent about Rs. 231,400 crores (at 1996-97 prices) on major, medium and minor irrigation works. As a result, the country's irrigation potential has increased from 23 million hectares in the pre-plan period (i.e.) 1950-51) to 89 million hectares at the end of 1996-97. India has the largest irrigated area among all the countries in the world.
Sources of irrigation Since 1950-51, considerable importance was attached to the provision of the canal irrigation. Canal irrigated area had increased from 8.3 million hectares to 18 million hectares during 1950-51 and 1999-2000. Even then, its relative importance has come down from 40 percent to 31.5 percent.
Well irrigated area has increased from 6 million hectares to 34 million hectares during last 50 years well irrigation in 1999-2000 accounted for nearly 59 percent of the local irrigation area as compared to only 29 per cent in 1950-51.
In India, irrigation words are classified into major medium and minor irrigation works. Since 1951, the major irrigation projects were defined as those costing more than Rs. 5 crores Medium irrigation as those costing between Rs. 25 lakhs, and minor irrigation works costing less than Rs. 25 lakhs.