In 1810 an Act of Parliament was passed authorising the construction of the Grand Union Canal from the Leicestershire and Northamptonshire Canal at Foxton to the Grand Junction Canal at Buckby.
The act opened a route from the River Thames at Brentford to the East Midlands, including the coalfields of Nottinghamshire and Derbyshire. The appointed engineer was Benjamin Bevan and work began immediately on the first major challenge, that of raising the canal 75ft up a steep escarpment at Foxton.
Bevan constructed two flights of five staircase locks. These are a unique design of locks where the locks share a pair of gates allowing a much steeper flight of locks to be constructed.
The locks took about two years to build and the canal was opened fully on the 9 August 1814 which is a remarkable feat given the available construction techniques of the time.
In 1894 the Grand Junction Canal Company took over the Leicestershire and Northamptonshire canal and the newly built Grand Union Canal which then became known as the Leicester Line of the Grand Junction Canal.
The locks today are essentially the same as they were when they were built which is a lasting testament to the design and the quality of the construction.
At the end of the 19th Century the amount of commercial traffic on the canals was in decline as more and more freight moved to the new railways.
In 1893, the company met with Mr Fellows, of the carrying company Fellow Morton and Clayton, who suggested that if the locks at Foxton and Watford were made wider, and the canal was dredged, conditions would be much better, and they would be able to run large steam boats, which would allow them to compete with the railways.
The company approved plans for the construction of the inclined plane in 1887 and in November the contract for the construction of the inclined plane was given to J & H Gwynne & Co of Hammersmith for a total price of £14,130 (over £1.4m today).
The design consisted of two counterbalanced caissons which could each hold two narrow boats or one wide-beam barge, and could raise or lower them the 75ft between the top and bottom of the lock flight in 12 minutes, compared to the 70 that using the locks took. The plane was powered by a steam engine located at the top of the plane in an engine house which is now the Boilerhouse Museum.
The plane was completed and began operating on 10 July 1900. Unfortunately, the plane was never a commercial success. Decreasing canal traffic, high running costs and the fact that the locks at Watford were never widened meaning that the wide steam boats never came, lead to the plane being mothballed in 1911 to save money before it was dismantled and sold for scrap in 1928.
The Boilerhouse Museum has films and models showing the construction and operation of the inclined plane
Last date edited: 6 February 2017