Investigation of the Influence of Excess Pumping on Groundwater Salinity in the Gaza Coastal Aquifer (Palestine) Using Three Predicted Future Scenarios

Mohammed Seyam,Yunes Mogheir,Taher Abunama,Augustine Chioma Affam,Mohammad Heydari,Khaled Ramlawi,Jawad S Alagha

doi:10.3390/w12082218

Abstract

The Gaza coastal aquifer (GCA) is the only source of water for about two million citizens living in Gaza Strip, Palestine. The groundwater quality in GCA has deteriorated rapidly due to many factors. The most crucial factor is the excess pumping due to the high population density. The objective of this article was to evaluate the influence of excess pumping on GCA’s salinity using 10-year predicted future scenarios based on artificial neural networks (ANNs). The ANN-based model was generated to predict the GCA’s salinity for three future scenarios that were designed based on different pumping rates. The results showed that when the pumping rate remains at the present conditions, salinity will increase rapidly in most GCA areas, and the availability of fresh water will decrease in disquieting rates by 2030. Only about 8% of the overall GCA’s area is expected to stay within 500 mg/L of the chloride concentration. Results also indicate that salinity would be improved slightly if the pumping rate is kept at 50% of the current pumping rates while the improvement rate is much faster if the pumping is stopped completely, which is an unfeasible scenario. The results are considered as an urgent call for developing an integrated water management strategy aiming at improving GCA quality by providing other drinking water resources to secure the increasing water demand.

Highlights

The main source of drinking water in the Gaza Strip is a shallow aquifer, which is part of the coastal aquifer
The low value of the error mean, Abs E. mean, and S.D. ratio showed that the error between the observed and simulated chloride concentration values using the Artificial Neural Networks (ANNs) model are small
By the selection of the three applied scenarios, it was intended to show the suitability of the model and to show the differences of the future salinity among them

Summary

Introduction

The main source of drinking water in the Gaza Strip is a shallow aquifer, which is part of the coastal aquifer. Salinity in the Gaza coastal aquifer (GCA) is characterized by a high chloride concentration, depending on the location and other hydrochemical processes [1,2]. Various processes may cause salinization of the groundwater, including seawater intrusion, movement of saltwater from the deeper layers of the aquifer, contribution from discharges from older formations surrounding the coastal aquifer, and dissolution of soluble salts in the aquifer. The root cause of the aforementioned GCA salinization processes is the unbalance of the groundwater system resulting from overpumping in the Gaza area, which is considered among the most populated regions in the world [3,4]. Potential man-induced (anthropogenic) sources, including agricultural return flows, wastewater seepage, and leachate from solid waste dumping sites, are involved in increasing groundwater salinity [5,6,7]

Objectives

Results

Conclusion