A COMPLEX £800,000 lifting and reassembly operation began on Tuesday at St Pancras Station, London, to move a 9m tall Grade 2 listed Victorian waterpoint out of the way of the Channel Tunnel Rail Link.
Specialist contractor Abbey Pynford, best known for the 1999 move of the Belle Tout lighthouse on the South Coast, had previously sliced the ornate Victorian Gothic masonry structure horizontally into three sections.
An 800t Demag AC2000 crane from heavy transport and lifting specialist Jim Parkinson was due to lift the 2.4m deep, 128t upper portion of the waterpoint onto a high tech transporter late on Tuesday afternoon. It will wait there until the middle 3.8m deep 110t section has been lifted onto its own transporter and moved 700m north.
Here a second 800t Demag AC3200 crane will lift the middle section onto a recreated lower section overlooking the St Pancras canal basin, before the top section follows.
The structure is the last of seven waterpoints built to supply water to steam locomotives at St Pancras. It supported a 63,000 litre cast iron water tank with large capacity delivery pipework.
'We discovered that one of the walls of the lower portion of the existing waterpoint was formed by the parapet of the wall across the east end of the St Pancras Cellars, a series of brick arches which carries the Midland Main Line into St Pancras, ' explained Stuart Armitage, project engineer for structural engineer the Morton Partnership.
'So the only alternative was to recreate the lower 5.3m by 8.9m section at the new site using specially produced pressed bricks from Ibstock.
But what is left behind will be carefully dismantled and everything of value salvaged.'
The new site is on top of a 5m high embankment dating from the early 1800s. Abbey Pynford special contracts head Tim Jolley said this location and the presence of services in the roads between meant that moving the upper 250t portion of the waterpoint as one unit was out of the question.
'Instead, we have very carefully cut the original structure into three sections along the mortar joints using special chainsaws with blades only 6mm thick. Steel plates were fed into the joint as the cutting progressed, and once the cuts were complete we could begin constructing the concrete ring beams.'
These grip the wall internally and externally at the bottom of each discrete section. Macalloy bars running through the beams from inside to out are post tensioned to increase the grip. A test jacking two weeks ago confirmed the integrity of the two sections to be moved - and their estimated weights.
Parkinson will use two sophisticated self propelled modular transporters with computer controlled steering that enables them to move in all directions.
The route will take both sections of the waterpoint up Goods Way and past the Camley Street nature park to the final destination on the viaduct. Final placement of the upper section is expected by Thursday.