Modelling seawater intrusion in the Pingtung coastal aquifer in Taiwan, under the influence of sea-level rise and changing abstraction regime | 海平面上升和改??采方案影?下的台?屏?沿海含水?海水入侵的模?研究 | Mod?lisation de l’intrusion d’eau de mer dans l’aquif?re c?tier de Pingtung ? Taiwan, sous l’influence de l’?l?vation du niveau de la mer et du changement du r?gime de pr?l?vement | Modelagem da intrus?o de ?gua do mar no aqu?fero costeiro de Pingtung, em Taiwan, sob a influ?ncia do aumento do n?vel do mar e da mudan?a do regime de abstra??o | Modelado de la intrusi?n de agua de mar en el acu?fero costero de Pingtung en Taiw?n, debido a la influencia de la elevaci?n del nivel del mar y el cambio del r?gimen de explotaci?n
Journal
Hydrogeology Journal
Journal Volume
28
Journal Issue
6
Pages
2085-2103
Date Issued
2020
Author(s)
Abstract
A three-dimensional variable-density finite element model was developed to study the combined effects of overabstraction and seawater intrusion in the Pingtung Plain coastal aquifer system in Taiwan. The model was generated in different layers to represent the three aquifers and two aquitards. Twenty-five multilayer pumping wells were assigned to abstract the groundwater, in addition to 95 observation wells to monitor the groundwater level. The analysis was carried out for a period of 8 years (2008–2015 inclusive). Hydraulic head, soil permeability, and precipitation were assigned as input data together with the pumping records in different layers of the aquifer. The developed numerical model was calibrated against the observed head archives and the calibrated model was used to predict the inland encroachment of seawater in different layers of the aquifer. The effects of pumping rate, sea-level rise, and relocation of wells on seawater intrusion were examined. The results show that all layers of the aquifer system are affected by seawater intrusion; however, the lengths of inland encroachment in the top and bottom aquifers are greater compared with the middle layer. This is the first large-scale finite-element model of the Pingtung Plain, which can be used by decision-makers for sustainable management of groundwater resources and cognizance of seawater intrusion in coastal aquifers. © 2020, The Author(s).
Other Subjects
climate change; coastal aquifer; flow modeling; groundwater abstraction; groundwater flow; saline intrusion; sea level change; seawater; software; Pingtung Plain; Taiwan
Type
journal article