Fanling Bypass Eastern Section featuring Hong Kong’s first bridge rotation

Enhancing regional connectivity

The FLBP is a vital component of the Fanling North New Development Area (FLN NDA), designed to support a population of around 74,000 residents. As part of the Northern Metropolis — a strategic initiative led by the Hong Kong SAR Government — the bypass strengthens regional connectivity and alleviates increasing traffic demand in this rapidly developing area.

Addressing over-the-rail construction challenges

© Civil Engineering and Development Department, HKSAR

A key challenge was constructing a vehicular bridge across an active railway line serving over 500,000 passengers daily, while contending with major underground utilities. Traditional segment erection methods would have required heavy lifting operations within limited night time windows, posing high operational risks.

To overcome these constraints, the team implemented the innovative horizontal bridge rotation method. A 140 meter long bridge section, weighing more than 7,000 tons (about 470 double decker buses), was built adjacent to Fanling Highway and the East Rail Line — an area further complicated by the presence of a water supply pipeline and high voltage cables.

The assembled bridge was then rotated horizontally into its final position overnight, enabling the structure to span the railway safely in a single operation. Advanced digital tools — including LiDAR systems, AI enabled CCTV and automated deformation monitoring — ensured precision and safety throughout construction and rotation.

This method shortened the construction programme by approximately 12 months compared with conventional techniques, significantly reduced on-site risks, and minimized disruption to railway operations, enhancing safety for both workers and the public.

Sustainable and collaborative delivery

Sustainability was central to project execution. Precast bridge deck segments were fabricated in Mainland China and installed using launching girders and mobile cranes, reducing on-site concrete works and achieving an estimated 2,100-ton reduction in carbon emissions.

As project consultant, AECOM coordinated design, engineering and delivery across multiple disciplines, fostering seamless collaboration among teams from Hong Kong, Mainland China and Singapore. This cross-regional partnership enabled efficient delivery and meaningful knowledge exchange.

Overall, the project delivered remarkable outcomes — reducing construction time, achieving around five percent cost savings, and setting a new standard for engineering innovation and excellence in Hong Kong’s infrastructure development.

Awards