Characterization of a Shallow Coastal Aquifer in the Framework of a Subsurface Storage and Soil Aquifer Treatment Project Using Electrical Resistivity Tomography (Port de la Selva, Spain)

Abstract

Water percolation through infiltration ponds is creating significant synergies for the broad adoption of water reuse as an additional non-conventional water supply. Despite the apparent simplicity of the soil aquifer treatment (SAT) approaches, the complexity of site-specific hydrogeological conditions and the processes occurring at various scales require an exhaustive understanding of the system’s response. The non-saturated zone and underlying aquifers cannot be considered as a black box, nor accept its characterization from few boreholes not well distributed over the area to be investigated. Electrical resistivity tomography (ERT) is a non-invasive technology, highly responsive to geological heterogeneities that has demonstrated useful to provide the detailed subsurface information required for groundwater modeling. The relationships between the electrical resistivity of the alluvial sediments and the bedrock and the difference in salinity of groundwater highlight the potential of geophysical methods over other more costly subsurface exploration techniques. The results of our research show that ERT coupled with implicit modeling tools provides information that can significantly help to identify aquifer geometry and characterize the saltwater intrusion of shallow alluvial aquifers. The proposed approaches could improve the reliability of groundwater models and the commitment of stakeholders to the benefits of SAT procedures.

Vulnerability of a Tunisian Coastal Aquifer to Seawater Intrusion: Insights from the GALDIT Model

“…Our study covers an area where SWI is progressively invading a coastal aquifer that is the primary water supply source for industrial, agricultural, and domestic uses [49][50][51][52][53][54][55]. Increasing demands for water in the region continue to put pressure on the GW resources.…”

Mapping Groundwater Potential for Irrigation, by Geographical Information System and Remote Sensing Techniques: A Case Study of District Lower Dir, Pakistan

“…Regional hydrogeological attributes, such as depth of weathering, drainage patterns, climate, extent of fractures, geological structures, landform, land cover/land use (LCLU), lithology, primary and secondary porosity, slope, and topography, regulate groundwater recharge [19,20]. In-site geophysics surveys and hydrogeology experiments assist to delineate processing involved in groundwater recharge and assess the spatiotemporal dissimilarities in the study regions [21][22][23]. Limited reliability of these surveys, mainly due to their focus on a single factor affecting groundwater recharge, have narrowed their role in predicting regional groundwater mapping [24].…”

Aquifer Storage and Recovery in Layered Saline Aquifers: Importance of Layer-Arrangements

“…Since ASR is often implemented in brackish or saline aquifers located in coastal or semi-arid and arid areas [7,[23][24][25], RE is reduced due to density-driven free convection and mixing of saline water with freshwater. Esmail and Kimbler [26] investigated the feasibility of ASR in confined homogeneous isotropic saline aquifers by performing an analytical analysis.…”