Project overview
The Alderney Water Treatment Works project includes the construction of a new Granular Activated Carbon Tank formed from 148 precast concrete units. Following completion of the base slabs, sumps and plinths, Carney Construction progressed into the main precast installation phase.
Key info
- 148 precast concrete units
- Unit weights from 5 to 17 tonnes
- Base slabs, sumps and plinths completed
- Liebherr LTR 1100 crawler crane
- Specialist precast lifting operation
- Granular Activated Carbon Tank structure
The works required a carefully planned lifting operation, with individual units weighing between 5 and 17 tonnes. Using the compact Liebherr LTR 1100 crawler crane, the team was able to offload, position and install the precast elements safely within a constrained working area.
Delivery
Substructure works
Before precast installation began, the team completed the reinforced concrete base slabs, sumps and supporting plinths.
These elements formed the foundation for the tank structure and required accurate setting out and dimensional control to ensure the precast units could be installed to the required alignment.
Precast installation
The tank is formed from 148 individual precast concrete units.
Each unit had to be lifted, manoeuvred and positioned in a controlled sequence, with unit weights ranging from 5 to 17 tonnes. The installation programme depended on close coordination between lifting operations, rigging teams and site personnel.
Craneage and logistics
The constrained site layout and weight of the precast units created demanding craneage requirements.
Carney Construction used its Liebherr LTR 1100 crawler crane for the operation. Its compact footprint, lifting capacity and manoeuvrability allowed the team to work efficiently while maintaining control of lifting zones, access routes and unit placement.
Safety and quality
The precast installation required strict control of lifting procedures, temporary stability and final positioning.
Each unit was installed in sequence and supported until the structure reached the required level of stability. This approach helped maintain safe working conditions while protecting alignment, joint accuracy and the quality of the finished tank.
Programme
The completion of the base slabs, sumps and plinths enabled the project to move into the main tank assembly phase.
The precast installation is being delivered against key programme dates, with lifting operations planned to maintain continuity while allowing sufficient time for rigging, placement and inspection.
Conclusion and summary
The Alderney Granular Activated Carbon Tank demonstrates Carney Construction’s capability in combining reinforced concrete substructure works with specialist precast installation.
The delivery of 148 units, including elements weighing up to 17 tonnes, required accurate preparation, controlled lifting and coordinated site logistics. The use of the Liebherr LTR 1100 supported safe and efficient installation within the available working space.
