From Underground to Smart City: Integrating Geological and ‎Hydrogeological Assessment into Sustainable Urban Planning and Risk ‎Management in Benghazi City, Libya

Abstract

Conventional smart-city frameworks overwhelmingly prioritize above-ground digital infrastructure while ignoring the subsurface geological and hydrogeological environment. This gap poses severe operational and structural risks to urban expansion, particularly in arid coastal settings subject to complex geohazards. This study presents an integrated spatial decision-support framework titled "From Underground to Smart City," designed to systematically incorporate digital geological, hydrogeological, and geomorphological datasets into smart-city planning for Benghazi City, eastern Libya. Utilizing a GIS-based spatial multi-criteria evaluation approach, the study identifies three critical subsurface hazard categories constraining urban growth: carbonate karst features (active and infilled dolines/sinkholes in areas like Buatni, Shebna, and Al-Kuwayfiya), coastal sabkhas characterized by shallow saline groundwater and weak compressible soils (e.g., Al-Sabri and Juliana), and altered drainage corridors within the Wadi Al-Qattara basin subject to flash flooding. Spatial temporal satellite analysis demonstrates severe urban encroachment onto these high-risk zones, severely impairing natural drainage and heightening structural vulnerability. The framework transforms complex subsurface technical data into actionable spatial layers, enabling urban planners to delineate hazard-prone exclusion zones, evaluate foundation stability, protect natural drainage pathways, and establish buffer corridors. By positioning subsurface intelligence as an indispensable tier of smart urban governance, this research provides a transferable empirical model for resilient, hazard-informed urban development across Libyan municipalities and similar arid Mediterranean coastal environments.