Hydrological Characteristics and Their Impact on Road and Bridge Networks in Wadi Bani Walid Basin Using Geographic Information Systems

Abstract

This study investigates the hydrological and morphometric characteristics  of the Wadi Bani Walid basin and examines their implications for the planning and design of road and bridge infrastructure. Such analysis is essential for infrastructure development in arid and semi-arid regions, where flash floods pose significant risks to transportation networks. The Wadi Bani Walid basin is one of the important seasonal drainage systems in northwestern Libya, located in the southern part of the Tripoli region. It covers an area of approximately 1,693 km², extending 111 km in length with an average width of 15 km. Elevation within the basin ranges from 157 m to 292 m above sea level.

The study employs Digital Elevation Model (DEM) data derived from ASTER imagery and utilizes Geographic Information Systems (GIS) techniques to perform detailed morphometric and hydrological analyses. These include the extraction of drainage networks, basin geometry, and surface characteristics, enabling accurate delineation and quantitative assessment of watershed properties. The results demonstrate a strong relationship between basin hydrological behavior and the vulnerability of road and bridge networks to flood hazards. The findings provide a scientific basis for improving drainage design, reducing flood risks, and enhancing the resilience and sustainability of transportation infrastructure.