The replacement of the fender timbers, flap valves and associated corrosion protection took place during the Spring of 2008, to programme and budget.
During low water periods approximately 100nr. fender timbers were removed and replaced, drilling the new timbers in situ to utilise the original fender brackets. To minimise the effect to normal operations of the Thames Barrier site, the Mackley jack-up barge was used in support of the works. Movements of the jack-up barge were co-ordinated with the requirements of the Port of London Authority, a requirement due to the proximity of London’s main tidal defence, the Thames Barrier.
Some 70nr. flap valves were removed and replaced with new items as part of the works, including localised repairs of the sheet piles as necessary. This work was undertaken on a tidal foreshore with the work again supported by the Mackley jack-up barge.
Once the flap valves were completed the corrosion protection system to the sheet piles below the new flap valves was replaced, using spray applied materials specially selected for their ability to cure underwater as the tide returned to the foreshore. Preparation media was environmentally considerate and captured as part of the process. Where necessary sheet pile clutches were welded up to prevent ground water running over the painted.