After more than 40 years of service, the tug berth pontoons in the Tidal Basin have been successfully replaced—marking a major step forward for safety, resilience and future readiness across the waterfront.
Concrete pontoons have been installed in place of older models at the west end of A and B Lock and an additional berth at South Wall. Unlike traditional steel or older-style pontoons, concrete pontoons are designed for long-term durability in marine environments. The reinforced concrete provides excellent resistance to corrosion, reducing maintenance requirements and extending service life. They also offer greater mass and stability, resulting in less movement under load and improved safety for personnel. This makes them particularly well-suited for handling large, powerful vessels such as the tugs.
The pontoons provide safe, stable berthing and access for vessels, acting as a critical interface between land and water, allowing crews to moor, embark and disembark safely, while accommodating tidal movement. Robust and reliable pontoons are essential to maintaining safe and efficient harbour operations given the operational demands of the Naval Base and the size and frequency of tug movements.
The new pontoons have been designed to support the current fleet, including SD Tempest, the largest tug in service, which has a displacement of 855 tonnes. The design also provides flexibility for future vessel requirements and changing environmental conditions. The project also included new supporting infrastructure including wall guides, brows, access bridges and upgraded water and electrical supplies.
Transitioning the pontoons from forty years old to future ready is no easy task. Delivering the project within a live operational naval base brought a number of challenges, including the need to maintain uninterrupted tug operations, work within limited tidal windows, and coordinate complex heavy lifting activities. Much of the work was carried out using sea-based plant, including a ‘multicat’ and supporting vessels, while a remote chain cutting machine was deployed to remove the old piles at seabed level.
The project was successfully completed through strong collaboration across multiple teams, including the KBS Waterfront Delivery Team, King’s Harbour Master, KBS Alongside Services, and our contractor Herbosch-Kiere. Consistent communication and joint planning throughout enabled teams to respond effectively to challenges and keep the project on course.
This upgrade not only improves safety and reliability today, but ensures the Tidal Basin is ready to support operations long into the future.
