Securing a Coastal City’s Water Supply with a Record-Breaking Marine Pipeline

Project:​ Saudi Arabia Jizan Industrial City Seawater Cooling Pipeline
Challenge:​ supplying massive volumes of seawater for industrial cooling, requiring the installation of a massive pipeline in the complex conditions of the Red Sea, where traditional materials face rapid corrosion.
HDPE Solution:​ The project involved the installation of a 6,600-meter-long High-Density Polyethylene (HDPE) pipeline with a world-record diameter of 3.5 meters. A key innovation was the use of an adaptive electrofusion welding ring technology. This system used hydraulic cylinders to ensure the welding ring perfectly conformed to the pipe’s dimensions, achieving a sealing precision of less than 1 mm and guaranteeing a leak-proof system crucial for marine environments.
To tackle the challenge of floating and installing these massive, flexible pipes, the engineering team developed a real-time navigation and monitoring system. Sensors placed along the pipe provided live data on its position and shape, allowing operators to adjust tugboats dynamically and reduce the risk of deformation by over 90%. For the final, critical sinking operation, a unique three-stage automatic deceleration system​ using airbags and sacrificial slings was employed. This controlled the descent speed to a safe 0.3 meters per second, ensuring the pipeline settled on the seabed with 99% accuracy without damaging the welds.
Results:​ The project set a new global benchmark for large-diameter marine pipelines. The corrosion-resistant nature of HDPE ensures a long service life with minimal maintenance, while the successful installation technique paves the way for similar large-scale marine infrastructure projects