it has also been noted that the rate of exploitation of groundwater is more than recharge across India . From 1980 onwards the share of use of groundwater becoming higher and the depletion of groundwater resource due to less recharge become critical . Excessive use of groundwater in agricultural sector creates hydrological imbalance and affects sustainability of the natural resources and water quality is also deteriorating with various contaminants such as arsenic , fluoride etc .
The number of groundwater schemes has increased in India rapidly , while that of surface water schemes has gone down across the country between 2006-07 and 2013-14 , resulting in growing dependency of farmers on subsurface resources . The number of surface water schemes such as flow and lift irrigations , however , has dropped from 1.24 million to 1.19 million . Groundwater still accounts for the lion ' s share 94.5 % of all the minor irrigation schemes in the country . At the national level , groundwater schemes are increasing but surface water schemes are declining .
Across India more than half of wells show declining groundwater levels . Declining surface water availability is forcing desperate and agitated farmers to increase groundwater use . If current trends continue northern India will face steadily declining agricultural outputs and severe shortages of potable water . Parts of Delhi
Newsletter No . 63 ; IRBMS consistently suffer serious water shortages every summer . The crisis , however , is not isolated to the north ; it is spreading slowly to other regions . A recent decade-long study of wells in Maharashtra , a west-central state , found that 70 % show a decline in groundwater levels .
In addition to scarce supply , water quality is a serious threat . India ’ s groundwater reserves are not only overexploited but also contaminated . The parliamentary report stated that deep-level groundwater is contaminated by sewage , fluoride , arsenic , and uranium . Incidence of arsenic contamination , as measured by number of affected habitations , doubled between 2013 and 2016 . In early 2017 , the Union Minister for Water Resources River Development and Ganga Rejuvenation stated that the need to raise awareness about arsenic contamination is urgent . In many West Bengal villages , residents have been drinking arsenic-contaminated water unwittingly for decades .
In India Groundwater is under constant threat from both agricultural and urban uses . The rates of natural replenishment are declining steadily threatening the sustainability of aquifers in the Indo-Gangetic Basin , which constitute one of Asia ’ s most densely populated and agriculturally productive regions . The Indus Basin , which accounts for a significant share of India ’ s
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Integrated River Basin Management Society