THE last of 292 concrete piles that will form the foundations for the UK’s longest railway bridge were installed this week.
It marks the end of the first phase of HS2’s Colne Valley Viaduct.
Once complete, the 2.1-mile bridge will carry the high-speed rail line across a series of lakes and waterways near Hillingdon.
Construction of the foundations, the 56 huge piers and the deck on top, have been happening in parallel – with separate teams working from north to south.
Deck assembly began last year, with more than 500 meters of the viaduct structure now complete.
To place 66 piles in the lake bed, HS2 had to build more than a kilometre of temporary jetties, with cofferdams to hold back the water around each set of foundations.
The jetties are also used to transport materials and equipment during construction of the piers and viaduct deck, keeping vehicles off the road.
HS2 is designed to improve rail links between London, Birmingham and the North.
HS2 Project Client David Emms said: “Completion of the piling is a major achievement and marks the end of almost two years of hard work.
“With pier construction and deck assembly also well underway, the viaduct is fast becoming one of the most impressive and recognisable parts of the project.”
The main deck of the viaduct is being built in 1,000 separate segments at a temporary factory nearby and assembled using a bridge-building machine.