CSSRI has prepared a first approximation of groundwater quality map on 1:6 million scale. Problems of poor water quality are generally associated with arid and the semi-arid regions and in coastal aquifers. 32 to 84 % area under arid and semiarid states is covered under saline/sodic groundwater.

Groundwater Quality in Select States of India

State Utilizable ground water resource
(M ha-m yr-1)
Use of poor quality waters
(M ha-m yr-1)
Area underlain by saline GW
(EC >  4 dS m-1) (km2)
Punjab 1.47 0.68 3,058
Haryana 0.86 0.47 11,438
U. P. 6.31 1.42 1,362
Rajasthan 0.95 0.65 1,41,036
Gujarat 1.56 0.26 24,300
Karnataka 1.24 0.17 8,804
Tamil Nadu 2.02 NA 3,300
All India 32.63 NA 1,93,438