Garstang Flood Barrier temporary works
In November 2024, VolkerGround Engineering supported VolkerStevin in delivering temporary works for the Garstang Flood Barrier.
This involved mobilising a SG75 Movax, an excavator base unit and a DH25 impact hammer to execute critical flood protection infrastructure enhancements.
VolkerGround Engineering’s scope of works encompassed design and installation support for the pile mat, including plant loading analysis and recommended installation methods. The team installed 64, AZ18-700 steel sheet piles, each 12.6 metres long, forming four small cofferdam structures. These cofferdams are to serve as the foundation for new concrete crane pads, essential for removing the existing flood barrier gates.
The work was methodically planned and executed in five key phases. All pile locations were preaugered using an excavator base machine equipped with an MPL drilling attachment to penetrate the stiff boulder clays.
The pile platform area was excavated, formed and redressed to ensure stability and safe operations. The team then installed the steel sheet piles using the SG75 Movax on the excavator base machine. VolkerGround Engineering’s next task was to back drive the piles, using a DH25 impact hammer to ensure alignment and embedment. Six shear studs were then securely installed on each pile to meet design specifications.
The team faced a number of logistical challenges whilst completing this project. The worksite was extremely narrow, barely accommodating the necessary machinery and equipment. VolkerGround Engineering implemented rigorous people-plant-interface standards, creating an additional pedestrian access point that routed employees via public footpaths, thereby avoiding proximity to operational plant.
The crawler crane operated with tracks retracted due to the narrow work area, resulting in reduced load and lift capacity. This challenge was mitigated by meticulous lift planning and sequencing.
All plant and material was delivered via a single-lane access track, which also served as a public right of way. Additional traffic marshals were deployed to manage deliveries safely and efficiently.
A public footpath crossed the worksite, and two others bordered the site. During high-risk activities like lifting and pitching piles, footpaths were closely monitored and use restricted to ensure public safety.
Working methods and sequencing were carefully planned to maintain a safe distance from the Environment Agency asset and monitoring station. Operators maintained line-of-sight supervision throughout operations.
Despite significant logistical and spatial constraints, VolkerGround Engineering successfully delivered the Garstang Flood Barrier temporary works with a strong focus on safety and efficiency. The collaborative efforts between VolkerGround Engineering and VolkerStevin ensured timely completion while maintaining strict adherence to safety and environmental guidelines.
