T265 Advances in Monitoring, Mapping, and Modeling Saltwater Intrusion and Groundwater Salinity

Wednesday, 18 October 2023
1:30 PM - 5:30 PM
319

WELL LOCATION INFLUENCE ON SEAWATER INTRUSION IN COASTAL AQUIFERS

Paper number: T265-4
Program: Technical Sessions
Time: 2:10 PM – 2:25 PM

Authors

Abstract

Coastal aquifers serve as an important freshwater resource for millions, but the increased groundwater extraction has exacerbated the risk of seawater intrusion (SWI). By understanding the influence of well pumping on SWI, we can better identify vulnerable aquifers and suggest water management policies to prevent contamination. Using 2-D SEAWAT groundwater flow and salt transport numerical models, we assess the extent of SWI in various aquifer characteristics (e.g. hydraulic conductivity, confining characteristics, recharge, etc.) and pumping schemes. Findings suggest that wells with deeper screened intervals located closer to the coast are most vulnerable to contamination, however well distance from the coastline matters more than well depth. If a system is not limited by recharge and the inland freshwater is at a constant head, the location of the pumping well is significant. This corresponds to topography-limited systems (i.e. aquifers in which the hydraulic heads are limited by topography rather than recharge). In addition to predicting which hydrogeologic conditions and well locations matter, we identify numerical model characteristics that may help water managers assess which existing well networks may be at the highest risk of contamination or determine future optimal pumping schemes.

Geological Society of America Abstracts with Programs. Vol. 55, No. 6

doi: 10.1130/abs/2023AM-392514

© Copyright 2023 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.