The Millennium Link was an ambitious £84.5m project with the objective of restoring navigability across Scotland on the historic Forth & Clyde Canal and Union Canal, providing a corridor of regenerative activity through central Scotland.
A major challenge faced, was to link the Forth and Clyde Canal, which lay 35m (115ft) below the level of the Union Canal. Historically, the two canals had been joined at Falkirk by a flight of 11 locks that stepped down across a distance of 1.5km, but these has been dismantled in 1933, breaking the link.
What was required was a method of connecting these two canals by way of a boat lift. British Waterways were keen to present a visionary solution taking full advantage of the opportunity to create a truly spectacular and fitting structure that would suitably commemorate the Millennium and act as an iconic symbol for years to come.
The Falkirk Wheel lies at the end of a reinforced concrete aqueduct that connects, via the Roughcastle tunnel and a double staircase lock, to the Union Canal. Boats entering the Wheel’s upper gondola are lowered, along with the water that they float in, to the basin below. At the same time, an equal weight rises up, lifted in the other gondola. This works on the Archimedes principle of displacement. That is, the mass of the boat sailing into the gondola will displace an exactly proportional volume of water so that the final combination of ‘boat plus water’ balances the original total mass.
Each gondola runs on small wheels that fit into a single curved rail fixed on the inner edge of the opening on each arm. In theory, this should be sufficient to ensure that they always remain horizontal, but any friction or sudden movement could cause the gondola to stick or tilt. To ensure that this could never happen and that the water and boats always remain perfectly level throughout the whole cycle, a series of linked cogs acts as a back up.
To commemorate the completion of The Millennium Link through the opening of The Falkirk Wheel by Her Majesty The Queen during her Golden Jubilee on 24th May 2002.