Ancient India

The earliest mentions of irrigation are found in Rigveda chapters 1.55, 1.85, 1.105, 7.9, 8.69 and 10.101.^[8] The Veda mentions only well-style irrigation,^[9] where kupa and avata wells once dug are stated to be always full of water, from which varatra (rope strap) and cakra (wheel) pull kosa (pails) of water. This water was, state the Vedas, led into surmi susira (broad channels) and from there into khanitrima (diverting channels) into fields.^[8]

Later, the 4th-century BCE Indian scholar Pāṇini, mentions tapping several rivers for irrigation.^[8][10] The mentioned rivers include Sindhu, Suvastu, Varnu, Sarayu, Vipas and Chandrabhaga.^[8] Buddhist texts from the 3rd century BCE also mention irrigation of crops.^[9] Texts from the Maurya Empire era (3rd century BCE) mention that the state raised revenue from charging farmers for irrigation services from rivers.^[8][11]

Patanjali, in Yogasutra of about the 4th century CE, explains a technique of yoga by comparing it to "the way a farmer diverts a stream from an irrigation canal for irrigation".^[12][13] In Tamil Nadu, the Grand Anicut (canal) across the Kaveri river was implemented in the 3rd century CE, and the basic design is still used today.^[11]

Medieval era

The most widespread irrigation system in India was undertaken in India in the medieval period by the Sultanate rulers. Firoz Shah Tughlaq (1309-1388) built the most extensive canal irrigation system around the Indo-Gangetic doab and the region west of the river Yamuna in the fourteenth century. These canals provided vast resources of water to agricultural lands in northern India as well as vital supplies of water to urban and rural settlements.^[14] These irrigation projects were continued by the subsequent rulers of northern India, particularly the Mughal rulers till the early eighteenth century. The British built the colonial canal networks on these medieval canal systems.^[15]

Colonial era

Ganges irrigation canal built during the colonial era, and inaugurated in 1854.

In 1800, some 800,000 hectares were irrigated in India.^[11] The Britishers by 1940 built significant number of canals and irrigation systems in Uttar Pradesh, Bihar,^[16] Punjab, Assam and Orissa.^[17] The Ganges Canal reached 350 miles from Haridwar to Kanpur in Uttar Pradesh. In Assam, a jungle in 1840, by 1900 had 1.62m hectares under cultivation, especially in tea plantations. In all, the amount of irrigated land multiplied by a factor of eight. Historian David Gilmour states British colonial government had built irrigation network with Ganges canal and that, "by the end of the century the new network of canals in the Punjab" were in place.^[18]

Much of the increase in irrigation during British colonial era was targeted at dedicated poppy and opium farms in India, for exports to China.^[19][20][21] Poppy cultivation by the British Raj required reliable, dedicated irrigation system.^[22] Large portions of the eastern and northern regions of India, namely United Provinces, Northwestern Provinces, Oudh, Behar, Bengal and Rewa were irrigated to ensure reliable supply of poppy and opium for China.^[23] By 1850, the Asian opium trade created nearly 1,000 square kilometers of poppy farms in India in its fertile Ganges plains, which increased to over 200.000 hectares by 1900.^[23] This diversion of food crop land to cash crop use, state scholars, led to massive famines over the 1850 to 1905 period.^[24][25]

Major irrigation canals were built after millions of people died each in a series of major famines in the 19th century in British India.^[11][25] In 1900, British India (including Bangladesh and Pakistan) had about 13 million ha under irrigation. In 1901 the Viceroy, Lord Curzon, appointed a Commission chaired by Sir Colin Scott-Moncrieff to draw up a comprehensive irrigation plan for India. In 1903 the Commission's report recommended irrigation of an additional 2.6 million hectares.^[26][27] By 1947, the irrigated area had increased to about 22 million ha.^[11] In Northwestern British India region alone, with the colonial government's effort, 2.2 million hectares of previously barren land was irrigated by the 1940s, most of which is now part of Pakistan.^[28] Arthur Cotton led some irrigation canal projects in the Deccan peninsula, and landmarks are named after him in Andhra Pradesh and Tamil Nadu. However, much of the added irrigation capacity during the colonial era was provided by groundwater wells and tanks, operated manually.^[29]

Statewise irrigation coverage and productivity

State-wise irrigation types, capacity and actual

Note: The All India total includes land area for Union Territories of India that is not shown in the above table.

Minor irrigation projects

This reservoir of the Mamer Minor Irrigation Project in Rajasthan is an example of a minor irrigation project

Minor irrigation project is a classification of irrigation projects used in India. A project with a designed to irrigate an area of 2000 hectares or less is classified as a minor irrigation ^[35][36][37] Before the Fifth Five-Year Plan, irrigation schemes were classified on the basis of investments needed to implement the scheme.^[35] Since the Fifth Five-Year Plan, India has adopted the command area-based system of classification.^[35]

Micro irrigation projects

Micro Irrigation Fund (MIF) of INR 5,000 crore was established "to bring more land area under micro-irrigation as part of its objective to boost agriculture production and farmers income", NABARD offers low interest rate to state govts "to promote micro-irrigation, which currently has a coverage of only 10 million hectares as against the potential of 70 million hectares." Drip irrigationis promoted.^[38]