Seawater intrusion along the indian Coast and in sankaraparani river Basin by multi techniques approach

Abstract

Seawater intrusion is a major concern in the coastal regions around the world as well as in India. About one-fourth of the total population is living in the coastal regions of India where groundwater is the major source of fresh water. Over pumping of groundwater in these regions will lead to seawater intrusion and a decrease in the availability of fresh groundwater. newlineThe study was carried out with the objectives to identify the locations of seawater intrusion along the Indian coast, to estimate the area of the coastal region affected by seawater intrusion, to identify the locations of seawater intrusion in the northern coast of Tamil Nadu, to delineate the extent of seawater intrusion in the coastal aquifer of Sankaraparani river basin, and to assess the vulnerability of coastal aquifer to seawater intrusion. newlineThe seawater intrusion is expected in the coastal regions of Andhra Pradesh, Tamil Nadu, Kerala, Karnataka, Maharashtra and Gujarat where the groundwater level is below mean sea level. Based on the groundwater level, nearly 7% of the total coastal area is affected by seawater intrusion. The higher decline in groundwater level is found in the northern part of the west coast such as Gujarat and the southern part of the east coast such as Tamil Nadu and Andhra Pradesh where groundwater is heavily pumped. The coastal regions of the east coast are more affected by seawater intrusion than the west coast due to the variation in topography and geological formation. Based on electrical conductivity, 11% of groundwater samples in the aquifers of the east coast were affected due to seawater intrusion. newline