Copperfield Gorge Dam Intake Structure Installation

Scope of Work

Removal of Old Intake Structure:

• Preliminary works:
  • Administration, management plans and net permit.
  • Mobilisation and site set-up.
  • Supply, transport, storage and delivery of all equipment, consumables and material required, including anodes and crocodile protection net.
  • Fabrication of AC pipe clamp used for disjoining and removal of the pipe sections.
  • Crocodile protection net installation.
• Remove top 2 platforms above water including knife valve spindle support, ladders, valves and steel pipes.
• Remove 5 platforms in water, not shown in contractual drawings, and all associated elements.
• Remove pipe stack, knife gate valves, support frames, etc.
• Perform ROV roller bucket inspection.
• Remove AC (asbestos concrete) pipe – disconnect the pipe for easier removal and assist asbestos removal professionals during the removal process in water.

Installation of New Intake Structure:

• Anode (12) installation to trash screen and bulkhead gate guide rails.
• Position concrete base formwork (formwork installed in two stages to allow for positioning under the existing structure).
• Clear/dredge (remove silt and other material) area next to existing intake pipe, within the formwork.
• Position reinforcement cage.
• Position steel trunnion base and HDPE trunnion.
• Bolt on the trunnion structure to existing steel flange.
• Concrete the trunnion base.
• Intake pipe following curing of the concrete (this included installation of top buoy and repositioning the top two clamps to fulfil design requirements).
• Install anchor to the dam wall using HIT-RE500 injection adhesive and position two concrete blocks, as per the design.
• Attach 3 individual guy wires to these elements on one side and secure the ring, connecting 3 guy wires, to clamp on the intake pipe on the other side.
• Multiple inspections of the river bed, formwork, existing elements, etc. in order to confirm assumptions and ongoing works’ progress.
• Site clean-up and de-mobilisation.