Canal is the second largest source of irriga­tion providing water to 29.24 percent of the net area under irrigation. The country has one of the world’s largest canal systems stretching over more than one lakh kilometres. Canals irrigated 82.95 lakh hectares of net irrigated area during 1950-51 (39.78%of the total net area under irrigation) which increased to 159.88 lakh hectares (29%) during 2000-01.

The irrigation canals are of two types, viz., (i) Inundation canals which are taken out directly from the rivers without making any kind of barrage or dam. Such canals use the excess water of rivers at the time of floods and remain operational during rainy season. Such canals have been taken out from the Satluj River in Punjab; (ii) Perennial canals are those which are taken out from the perennial rivers by construct­ing barrage or weir to regulate the flow of water.

Most of the canals of the country belong to this group. Canal irrigation is widely practiced in the Satluj-Ganga plain. Uttar Pradesh, Punjab, Haryana, Bihar and Rajasthan have a number of such canals. In the Peninsular region canals are mostly found in the lower valleys and deltas of large rivers. Over 63 per cent of the total canal irrigated area of the country lies in Uttar Pradesh. Madhya Pradesh, Andhra Pradesh, Punjab, Rajasthan and Haryana. Canals also feed a sizeable part of the irrigated area in Bihar, Orissa, Karnataka, Tamil Nadu and West Bengal.