Hydrogeologic assessment for groundwater prospects in Al-Abwa drainage basin, arid-terrain of Arabian Shield, Saudi Arabian Red Sea coastal belt

Abstract

Arid regions are considered the most vulnerable areas regarding the water crisis. Al-Abwa drainage basin, situated at western arid part of the Saudi Arabian Shield region, presents a complex hydrogeological setup along the Red Sea coastline. Historically, the groundwater was used to extract from shallow thin alluvial aquifers underlain by the basement rock terrains. With time, rapid increase in population with changes in lifestyle and associated faster urban, industrial, and agriculture development activities caused stresses on the water demand for further socio-economic growth in the basin. As such, dependency on desalinated seawater supply from the Red Sea became unavoidable. A research study was carried out for appraisal of the groundwater potential associated with the thin alluvial aquifers, and new aquifers within the Cenozoic lava flows and Precambrian rock terrains in the basin. The study included the hydrogeological field investigations, the evaluation of exposed geological setup, the watershed characterization and the satellite remote sensing analyses and modeling. Results have provided clear understanding about the hydrogeological conditions in terms of tentative groundwater quality, expected quantity, utilization trends, hydro-characteristics of exposed rock units, precise delineation of Al-Abwa basin/sub-basins, structural impacts on flowing patterns of drainage networks, hydro-geomorphic parameters, recharging and discharging characteristics, impacts of auto-extracted lineaments and their density anomalies. Integration of various accomplished sub-studies revealed bright prospects of the fault/fracture zone(s) aquifers within Precambrian rock terrains in Al-Abwa drainage basin, which were recommended for further detailed geophysical and test drilling exploration.