ABSTRACT
Groundwater development provides assured water supply for agricultural, municipal, and industrial activities. The agricultural groundwater development not only augments the canal water supply, but also facilitates timely irrigation at critical times. However, several aquifers worldwide contain fresh usable groundwater only in a not-so-thick layer toward the top. This freshwater layer is underlain by a relatively thick layer of unusable saline water. Such Fresh–Saline aquifers (termed henceforth as F–S aquifers) occurring invariably in coastal regions are quite common in inland aquifers also. In coastal regions, groundwater salinity is mostly of marine origin such as salinity originating from marine transgressions, seawater intrusion, incidental flooding by seawater, and groundwater enriched in salts by seawater sprays. In inland areas and parts of coastal areas, groundwater salinity is of terrestrial origin that can be attributed to natural or anthropogenic factors. Natural factors include groundwater enrichment in salts by evaporation at or near land surface or by dissolution of naturally occurring soluble minerals underground while anthropogenic factors include groundwater enrichment in salts by irrigation and subsurface waste disposal.
