Flood hazards in an urbanizing watershed in Riyadh, Saudi Arabia

Abstract

Riyadh, the capital of the Kingdom of Saudi Arabia, has experienced unusual levels of urbanization in the past few decades, making it one of the fastest growing cities in the world. This paper examines flood hazards in the rapidly urbanizing catchment of Al-Aysen in Riyadh. Remote sensing and geographic information system techniques were employed to obtain and prepare input data for hydrologic and hydraulic models, with the former based on the very popular curve number approach. Due to the limited nature of the rainfall data, observations from two rain gauges in the vicinity of the catchment were used to estimate design storms. The hydrologic model was run in a semi-distributed mode by dividing the catchment into many sub-catchments. The impact of urbanization on run-off volume and peak discharge resulting from different storms was investigated, with various urbanization scenarios simulated. Flood hazard zones and affected streets were also identified through hydrologic/hydraulic model simulation. The mismatch between administrative and catchment boundaries can create problems in flood risk management for similar cities since hydrologic processes and flood hazards are based on the hydrologic connectivity. Since flooding events impact the road network and create driving hazards, governmental decision-makers must take the necessary precautions to protect drivers in these situations.

Hydrometeorological Analysis of Tropical Storm Hermine and Central Texas Flash Flooding, September 2010

“…Moreover, Texas consistently leads the nation in flash flood-related deaths, the majority of which occur across central Texas in an area dubbed Flash Flood Alley (FFA; Zahran et al 2008;Sharif et al 2012). FFA is oriented from north to south across the central portion of the state, extending approximately from San Antonio to Dallas, Texas (TX).…”

A Hydrological and Geomorphometric Approach to Understanding the Generation of Wadi Flash Floods

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Physically, Fully-Distributed Hydrologic Simulations Driven by GPM Satellite Rainfall over an Urbanizing Arid Catchment in Saudi Arabia

“…Physically based, distributed models employ a gridded nature, which allows parameters to be constrained within certain ranges that have clear physical meanings. Recent research demonstrated that physically-based, distributed hydrologic models can potentially perform as well as-or outperform-calibrated conceptual, lumped models [24][25][26][27]. The physically-based Gridded Surface Subsurface Hydrologic Analysis (GSSHA) model is an example of a grid-based fully-distributed hydrologic models [28].…”

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