Pembroke Power Station Cofferdam Installation & Removal

Kaymac Marine & Civil Engineering Ltd was commissioned by RWE npower to design, install and then later remove a cofferdam system to seal the cooling water intakes to the former Pembroke Power Station, which was constructed between 1965 and 1968 and stopped generating electricity in 1997. RWE npower were constructing a new 2000MW combined cycle gas turbine (CCGT) power station at the site and the existing cooling water intakes will be incorporated into the new design.

Prior to the cofferdam installation, over 2500m3 of silt was dredged from inside and around the intakes. A propping system was then installed to support the outer chamber wall and finally the 17 cofferdam sections weighing over 10T each were lowered into position and bolted together.

The cofferdam was then pumped out to provide a safe dry working area for remedial works to be carried out within the intake chamber. Kaymac returned to site at a later date to remove the structure once the remedial works had been completed. The structure was removed through the use of a 70T crane being operated from floating plant.

The project was delivered to the client on time and within budget.