Shipping operator P&O is introducing two new vessels on its Australia-Europe run.
They will ply between the Antipodes and the Thames estuary port of Tilbury. To accommodate the 52,600t displacement giants, additional deep water berthing and container handling capacity is needed.
Tilbury handles a mix of bulk and general cargoes, and 450,000 containers a year. Additional trade is predicted to double container throughput and the port operator, a consortium of Associated British Ports, P&O Ports and Port of Tilbury (London) known as Tilbury Container Services, is embarking on a £17M construction project aimed at delivering the necessary capacity.
There is just one, 305m long deep water berth at Tilbury. However, the site, on the outside of a river-bend, is cramped. Hemming in the existing quay to the south is a lock connecting to the port's non-tidal basin. A stone's throw to the north juts Tilbury Grain Terminal jetty. It is just far enough off to allow an additional 285m of quayside to be squeezed in, and allow a modest increase in the container handling area. 'With clever mooring, P&O will be able to get both ships alongside at the same time, ' says director of consultant Posford Duvivier, Simon Greenway.
Posford Duvivier has been appointed designer and project manager for the extension. Where the existing quay is an open, piled structure supporting a reinforced concrete deck, outline design for the new quay shows a solid structure fronted with a sheet piled wall. Steel and reinforced concrete structures will have a 60-year design life; services and paving 15 years. The design and build construction contract is expected to be let at the end of this month.
Ground conditions have been a key factor in the quay design. The estuary is composed of an upper layer of soft sediments and clays. To avoid settlement these will have to be excavated to reveal stable gravel strata. A grid of 762mm diameter tubular steel piles will then be driven into underlying chalk.
Some excavated material will be reclaimed as fill for the quayside and consolidated. However, the contractor will be forced to dispose of material either at an offshore dump ground or, more expensively, on land at a registered landfill site.
Options have to be negotiated with the Ministry of Agriculture Fisheries & Food and the Environment Agency, which are keenly watching the project to ensure minimum environmental damage.
TCS moves 22% of goods through Tilbury by rail. It is keen to increase rail freight to 30%. With overall trade increasing twofold, in the long term Tilbury 'probably needs new rail infrastructure, ' says Greenway.