T95 Water Resources and Management in Coastal and Inland Aquifers—Emphasis on Small Island Developing States of the Caribbean

Monday, 23 October 2017
8:00 AM - 12:00 PM
Room 615/616/617

GEOMORPHIC CONTROL ON OCCURRENCE OF FRESH GROUNDWATER IN A SALTWATER INTRUDED COASTAL AQUIFER

Paper number: T95-15
Program: Technical Sessions
Time: 11:25 AM – 11:40 AM

Authors

Abstract

Intrusion of saltwater into coastal aquifer deteriorates the groundwater quality and affects the freshwater availability in the coastal regions. A study has been conducted with the aim to (i) demarcate the potential fresh groundwater zones, and (ii) determine the processes that control fresh groundwater availability in the coastal areas of Puri district of Indian state of Odisha. Sixty-eight groundwater samples were collected from tube wells extending up to 10 km inland along 120 km stretch of the coast. Various physico-chemical parameters such as Electrical Conductivity (EC), Total Dissolved Solids, pH and concentrations of major ions were determined. Majority of the collected water sample (56%) falls in brackish water category, as their EC values higher than 1500 µs/cm has been registered. The major ion composition of the collected water samples indicate the intrusion and mixing of saltwater with the fresh groundwater in the inland areas up to an extent of 5-7 km. Interestingly, the water samples close to shoreline show freshwater characteristics and fall in Ca-Mg-HCO3 field of the Piper diagram. With the help of Enhanced Thematic Mapper Plus (ETM +) Pan Mosaic images and digital elevation model, it has been identified that these freshwater patches exist on buried paleochannels and sand dunes, which act as perched aquifer to store fresh groundwater. The demarcation of perched aquifers for groundwater exploration may provide an immediate solution to deal with the problem of freshwater scarcity in the coastal areas.

Geological Society of America Abstracts with Programs. Vol. 49, No. 6

doi: 10.1130/abs/2017AM-296298

© Copyright 2017 The Geological Society of America (GSA), all rights reserved. Permission is hereby granted to the author(s) of this abstract to reproduce and distribute it freely, for noncommercial purposes. Permission is hereby granted to any individual scientist to download a single copy of this electronic file and reproduce up to 20 paper copies for noncommercial purposes advancing science and education, including classroom use, providing all reproductions include the complete content shown here, including the author information. All other forms of reproduction and/or transmittal are prohibited without written permission from GSA Copyright Permissions.