Underground solution for urban resilience: Stormwater management infrastructure

• Published in: Expanding Underground - Knowledge and Passion to Make a Positive Impact on the World pp. 90 - 98
• Main Authors: Koliji, A., Kazerani, T., Questi, G., Senn, J.
• Format: Book Chapter
• Language: English
• Published: United Kingdom CRC Press 2023; Taylor & Francis Group
• Edition: 1
• Subjects: Front Advancement; Circular Shaft; Bottom Slab Concreting; Safety Factor; Geological Strength Index; Slurry Walls; Stormwater Management Infrastructure; Overburden; Pumping Station; Jet Grouting; Project Preliminary Design; Engineering Change Proposal; Deep Drainage; Above Ground; MSL; Confinement Convergence Method; BIM Model; RD; Critical Hydraulic Gradient; Diaphragm Wall; Diaphragm Wall Panels; SEM; Surface Runoff Hydrograph; VE Concept; SCL
• DOI: 10.1201/9781003348030-12

In past decades, stormwater management has become an essential component of climate-change resilient urban development. Replacement of natural pervious areas with impervious surfaces increases stormwater runoff volumes and peak flows. In the absence of sufficient drainage system, cities are subject to urban flooding with potential loss of life and property damage. Underground solutions with network of smart tunnels and pumping stations are of a central role for urban resilience. The present paper studies a stormwater infrastructure in the city of Jeddah in the Kingdom of Saudi Arabia. In the framework of Jeddah Stormwater Drainage Program and Masterplan, a new pump station known as Al-Salam Pump station, is planned to discharge the incoming flow from the storm water tunnel to the Red Sea via an outfall. The design and construction of the deep large-diameter shafts close to the sea as well as their intersection with the connecting tunnels involved several technical challenges. Geotechnical analyses combined with advanced numerical methods were used for an optimized design. As an overall assessment, a Value Engineering study of the proposed solution was carried out highlighting the Value Engineering Concepts, their technical evaluation and engineering development as well as cost, risk and sustainability impact on the project. In the absence of sufficient drainage system, cities are subject to urban flooding caused by extreme runoff with potential loss of life and property damage. The city of Jeddah in the Kingdom of Saudi Arabia is located with a generally dry region with infrequent rainfall patterns. In recent years, the city has experienced cases of sudden intensive rainstorms with urban floods, including 2009 floods with several casualties and significant damages. The Al-Salam Pump station is located in the Jeddah coastal zone and discharges the water from an incoming storm water tunnel into the Red sea. The project is located in the urban area and thus, facing several constraints not only for design but also for logistics and construction works. The hydraulics operation and design criteria of the pumping station, including the shaft, wet well and the channels, were defined in the preliminary design.