Analysis of seawater intrusion triggered under different pumping well layout schemes based on a numerical model

Abstract

Seawater intrusion (SWI) is a consequence of communication between the ocean and inland groundwater entailed by overexploitation and has been a global issue harming production, life and ecology in coastal regions. This paper established a numerical model to identify SWI features in a wider space under different pumping‐well layouts based on the number of wells (N), distance between the coastline and wells (Dcw), and distance between wells (Dww) and further researched the influence of the location of the screen (Ls) and calculated S as an index inferring the SWI degree. An evaluation index (EI) was proposed considering two contradictory parameters: the corresponding total critical pumping rate (Qc) indicated the critical situation in which saltwater was almost pumped, played a good role as the resource function, and S referred the negative environmental impact. Sensitivity analysis was performed to explore the relationship between the evaluation indexes and the parameters of pumping well layouts. The results revealed how seawater intruded inland groundwater under different pumping well layouts and the anthropogenic impact factors influencing the SWI process. Sensitivity analysis verified that Dcw was the key factor in optimizing pumping well layouts to maximize the quantity of groundwater resources and minimize the environmental damage of SWI. Research on Ls revealed that a higher location of the screen of the well could effectively abate SWI. This research fully explained SWI characteristics under different pumping well layouts and proposed the key factors during coastal groundwater exploitation work, which enhanced the understanding of SWI and contributed to the arrangement of real‐world water pumping activities in coastal regions.