Explanation:

Since 1950-51, the government had given considerable importance to the development of command area under canals. In 1950-51, the Canal irrigated area was 8.3 million hectares and it currently stands at 17 million hectares. Despite that, the relative importance of Canals has come down from 40% in 1951 to 26% in 2010-11. On the other hand, the well (16%) and tube well (46%) accounted for 29% total irrigated area and now they share 64% of the total irrigated area.
This implies that “despite of heavy public expenditure on canals, our governments have not been able to reduce the groundwater depletion” done by the remarkable progress of the tube wells in last many decades. The key reason is widening gap between irrigation potential created and actually utilized.