Irrigation and groundwater depletion

Why irrigate? Rainfall varies in space and time: some regions get little, and winters and summers are largely dry. Crops like rice, sugarcane and jute need a lot of water. Irrigation also allows multiple cropping (more than one crop a year) and higher yields.

In Punjab, Haryana and western Uttar Pradesh, over 85 per cent of the net sown area is irrigated.

But much of this water comes from wells and tubewells (76.1 per cent of Punjab's irrigation). Pumping water out faster than rain can refill it has lowered the water table.

Over-withdrawal also raises harmful substances in groundwater: fluoride (in Rajasthan and Maharashtra) and arsenic (in West Bengal and Bihar).

The Pradhan Mantri Krishi Sinchayee Yojana (PMKSY, 2015-16) aims at 'Har khet ko pani' (water for every field) and 'more crop per drop' (using water efficiently, as with drip irrigation).