Irrigation is essential for agricultural operations where rainfall is deficient and erratic. It eliminates or at least reduces the dependence of agriculture on the vagaries of rainfall. While some areas of our country have plenty and near-assured rainfall, there are also vast areas with uncertain rainfall, thus spelling out the desirability of a system of assured irrigation. Some of the rain-fed areas of our country undergo periodical droughts or floods. It is also worth noting that some crops like rice, sugarcane and others need a lot of water and timely irrigation. Moreover, assured irrigation provides a scope for two or\ more crops per year from the same fields and this adds to the income of the farm sector, more employment in the rural areas and other benefits to the economy as a whole.
Irrigation system has existed in India since time immemorial. Over time, we developed several means of irrigation including tanks, wells and canals. Post-Independence period saw large scale mushrooming of tube-wells as also a vast extension of the canal network. Unfortunately, this has been accompanied by an avoidable neglect of tanks.
Consequently, today we have the world’s largest irrigated area in the world. According to the Economic Survey, country’s ultimate irrigation potential (DIP) is estimated at 139.89 million hectares. So far, about 68% of UIP has been harnessed. Currently, the pace of net addition to irrigation potential is sought to be accelerated under various schemes. However, our approach to irrigation still suffers from various drawbacks.
(a) We have a large unexploited potential of irrigation facilities, but their pace of the development is far below the optimum,
(b) The maintenance of irrigation facilities is extremely poor. As a result, the effective availability of facilities has a tendency to fall into disuse. Moreover, their current use is below the optimum level.
(c) As a matter of general apathy, several traditional irrigation and water harvesting facilities (like tanks and dug wells) have fallen into disuse.
(d) There is a need to ensure that water carried by rivers and streams to the sea is utilized to the extent possible for increasing its availability for domestic and industrial uses and for inland waterways. A coherent and effective policy to this end can help our economy in several ways, such as, generation of electricity, checking soil erosion and soil degradation, provision of cheap transport, development of fisheries, and the like. But for various reasons, including non-economic ones, such a coherent and effective policy is not in place.
(e) As against the limited availability of water, we have promoted the cultivation of some crops like rice and sugarcane which need large scale water. Moreover, this has happened in areas having insufficient water availability. This has led to a shortage of water for irrigating remaining crops,
(f) As noted above, a major portion of water from rain and melting of snow is allowed to run into the sea. This has the added ill effects of simultaneously causing both floods and drought in different parts of the country.
(g) In some areas, particularly those which have a moderate rainfall but concentrate on cultivation of rice and sugarcane, indiscriminate mining of groundwater has taken place through tube-wells, resulting in a steady lowering the water table in these areas.
(h) The surface water flow in rivers and streams is getting increasing polluted by untreated industrial effluents. Consequently, it is becoming increasingly unfit both for drinking and for irrigation.
(i) There is a vast untapped potential of rainwater harvesting in areas like Rajasthan and Madhya Pradesh. If rainwater is properly checked in such areas, we can raise the table of groundwater and add to the productivity of land.