The increase in water demand due to rapid increase in population, urbanization and industrialization is posing a major challenge to the global water resources. The ground system of India is the largest, currently, covering 160 million ha of cultivated land in India with 39 million ha irrigated by groundwater and 22 million ha by irrigated canals. India’s groundwater crisis, fuelled by intense pumping, specifically in northern India is being depleted at a rate of 19.2 gigatons per year which is equivalent to almost a third of the capacity of one of India’s largest reservoirs by water capacity, the Indira Sagar in Madhya Pradesh, said Matthew Rodell who works at NASA.
More than 80% of available water resources in India is being currently utilized for irrigation purposes where, the average water use efficiency of irrigation projects is assessed to be only of the order of 30-35%. The agriculture sector, in addition to providing a source of livelihood for almost 50 percent of India’s population, also accounts for 78 percent of the total water used in the country. Further, as per NCIWRD report, the percentage of water used for irrigation in India out of the total water use for the year 2025 under high demand scenario was estimated as 72.48%. An example could be seen in Haryana and Rajasthan were 40%-75% of the groundwater units are overused, and the one in Punjab where 75%-90% of groundwater units are exploited. Despite receiving one percent higher than normal rainfall between 2003 and 2015, northern India experienced severe groundwater depletion primarily due to widespread over extraction for irrigation of crops like rice and wheat. it is estimated that agricultural production will need to expand by approximately 70% by 2050.
The future demand on water by all sectors is estimated to require as much as 25 to 40% of water to be re-allocated from lower to higher productivity and employment activities, particularly in water stressed regions. In most cases, such reallocation is expected to come from agriculture due to its high share of water use. Currently, agriculture accounts (on average) for 70 percent of all freshwater withdrawals globally (and an even higher share of “consumptive water use” due to the evapotranspiration of crops).
Almost 80% of water supply flows back into the ecosystem as wastewater. While the study projects rainfall to increase by 12 percent by 2100, Rodell warned “it will be too little, too late.”