Quality Assessment of Groundwater in the Vicinity of Coir Retting Areas of Kadinamkulam Estuary, South India

The present study was conducted in the selected groundwater bodies of the coastal gramapanchayath near Kadinamkulam estuary during the pre-monsoon, monsoon, and post-monsoon seasons. Kadinamkulam estuary is one of the major coir-retting areas in Kerala. The major objective of the study is to assess the physico- chemical characteristics and hydrogen sulfide pollution of groundwater in the residential areas of Azhoor Gramapanchayath in Thiruvananthapuram district. Surface water samples from selected stations were also collected from the Kadinamkulam estuary. The physico-chemical characteristics of water were analyzed following the standard procedures in APHA (2012). The results show that the recorded values for color, pH, phosphate, calcium, magnesium and hydrogen sulfide were above the permissible limits of drinking water quality standards (Bureau of Indian Standards, 1991; WHO, 1993, 1996). This may be due leaching of effluents from the coir retting activity in the Kadinamkulam estuary and due to the disposal of solid wastes. The study also revealed that the hydrogen sulfide content was high in lake water samples which affect the primary productivity of the water body. The correlation and principal component analysis shows that color is an important parameter and from cluster, analysis it was found that phosphate and hydrogen sulfide content significantly affect the groundwater quality. The study concludes that the groundwater sources in the study area are getting contaminated due to the leaching of pollutants from Kadinamkulam estuary and anthropogenic activities in the nearby residential areas.