Brief Description
The four hydraulic boat-lifts on this short stretch of the historic Canal du Centre are industrial monuments of the highest quality. Together with the canal itself and its associated structures, they constitute a remarkably well-preserved and complete example of a late-19th-century industrial landscape. Of the eight hydraulic boat-lifts built at the end of the 19th and beginning of the 20th century, the only ones in the world which still exist in their original working condition are these four lifts on the Canal du Centre.
Justification for Inscription
Criterion iii: The boat-lifts of the Canal du Centre bear exceptional testimony to the remarkable hydraulic engineering developments of 19th-century Europe.
Criterion iv: These boat-lifts represent the apogee of the application of engineering technology to the construction of canals.
Long Description
The four hydraulic boat-lifts on this short stretch of the Canal du Centre, together with the canal itself and its associated structures, constitute a remarkably well-preserved and complete example of a late 19th-century industrial landscape. They represent the apogee of the application of engineering technology to the construction of canals and bear exceptional testimony to the remarkable hydraulic engineering developments of 19th-century Europe. Of the eight hydraulic boat lifts built at the end of the 19th and the beginning of the 20th century, the only ones still in existence in their original working condition are the four lifts on the Canal du Centre.
Hainault does not have a large natural navigable waterway. This led to difficulties in transporting the coal discovered in the region in the Borinage and around Charleroi at the end of the 12th century on the poor roads of the time. It was carried on the backs of men to the shore of the winding Haine River and loaded into small boats. Considerable works were carried out to improve the navigation of the Haine in the centuries that followed, so that larger boats could carry coal from Jemappes to the lower Scheldt, including the provision of sluice locks and gates. With the transfer of the Condé region to France in 1655, plans to link the Mons area to the Scheldt by canal were first discussed, but no progress was made until the early 19th century.
The Charleroi-Brussels Canal was finished in 1832, and the Houdeng and Mariemont branches, which were to play an important role in the development of the Canal du Centre, in 1839. An imperial decree of Napoleon I in 1807 ordered the construction of a canal between Mons and Condé, and this was completed in 1818. With the Saint-Quentin Canal, completed in the same year, the Borinage coalfield was now connected directly with Paris. Only one element was missing in this canal network linking the Scheldt and the Meuse, a canal between Mons and Charleroi. This proposal to construct what was known as the Canal de Centre had originally been approved by Napoleon I in 1810.
Studies were carried out by the Belgian Government aimed at overcoming the two major technical problems - the small quantity of water available and the large difference in level (89.46 m). The main problem lay in the upper part of the canal, in the Thiriau valley. It was decided that on this stretch the change in level was such that it might be better dealt with by means of lifts rather than locks: four lifts of the type developed by the English engineer Edwin Clark would be sufficient, one with a difference in level of 15.40 m and the other three of 16.93 m. The work was put out to tender, and the construction work of Lift No. 1 at Houdeng-Gœgnies was completed in April 1888; it was inaugurated on 4 June that year by King Leopold II of the Belgians.
Lift No. 1 (Houdeng-Gœgnies) consists essentially of two mobile compartments, each supported by a single hydraulic press, the latter being joined by pipes in such a way that, when one compartment is at the level of the upper bay, the other is at the level of the lower bay. As the first descends as a result of the introduction of water from the upstream bay, the other rises; a sluice gate in the middle of the pipe between the two presses governs the movement of the compartments.
Lifts No. 2 (Houdeng-Aimeries), No. 3 (Bracquegnies) and No. 4 (Thieu) were built 13 years after No. 1 came into operation, and they incorporate a number of modifications to the basic design resulting from operational experience. However, the operating principle remains the same; the modifications apply mainly to the guides, the hydraulic presses and their pistons, and the gates.
Historical Description
Hainault does not have a large natural navigable waterway. This led to difficulties in transporting the coal discovered in the region in the Borinage and around Charleroi at the end of the 12th century on the bad roads of the time. It was carried on the backs of men to the shore of the winding Haine river and loaded into small boats. Considerable works were carried out to improve the navigation of the Haine in the centuries that followed, so that larger boats could carry coal from Jemappes to the lower Scheldt, including the provision of sluice locks and gates. With the transfer of the Condé region to France in 1655, plans to link the Mons area to the Scheldt by canal were first discussed, but no progress was made until the early 19th century. The Charleroi-Brussels Canal was finished in 1832, and the Houdeng and Mariemont branches, which were to play an important role in the development of the Canal du Centre, in 1839.
An Imperial decree of Napoléon I in 1807 ordered the construction of a canal between Mons and Condé, and this was completed in 1818. With the Saint- Quentin Canal, completed in the same year, the Borinage coalfield was now connected directly with Paris. Only one element was missing in this canal network linking the Scheldt and the Meuse, a canal between Mons and Charleroi.
This proposal to construct what was known as the Canal de Centre had originally been approved by Napoléon I in 1810. There was to follow a long series of projects, by French, Dutch, and Belgian engineers, on different routes and using different techniques for solving the technical problems encountered between the two ends. These were all essentially commercial schemes, funded by the enterprises who would make use of the new link. Increased competition from British, German, and northern French coalfields led the Belgian Government to intervene in 1871 and undertake to finance the canal. Studies were carried out by its Civil Engineering Authority aimed at overcoming the two major technical problems - the small quantity of water available and the large difference in level (89.46m) between the Charleroi- Brussels and Mons-Condé canals.
The main problem lay in the upper part of the canal, in the Thiriau valley. It was decided that on this stretch the change in level was such that it might be better dealt with by means of lifts rather than locks: four lifts of the type developed by the English engineer Edwin Clark would be sufficient, one with a difference in level of 15.40m and the other three of 16.93m. These would accommodate both the difference in level on this stretch of the canal and the low supply of water, since Clark lifts had been shown to be very economical from this point of view. Belgian engineers were sent to England to study the only existing example of this type of lift, that built by Clark at Anderton on the Trent-Mersey Canal in 1872-75.
Despite some setbacks, as when there was an accident at the Anderton lift in 1881, leading to an increase in the safety coefficient to be adopted, the decision to go ahead was finally taken at the end of 1884. Clark himself was to be involved in the design and construction of the Belgian lifts. The work was put out to tender, and the construction work of Lift No 1 at Houdeng-Goegnies was completed in April 1888; it was inaugurated on 4 June that year by King Leopold II of the Belgians.
Work on the completion of the canal itself and of the other three lifts was, however, not to be completed so speedily, for a variety of reasons. The 14km stretch from Mons to Thieu was opened in 1892, but further work was delayed because it was discovered that other stretches of the canal ran through an area pitted with abandoned coal mines. It was not until 1909 that work began on the remaining three lifts, built, like No 1, by the Cockerill company in Seraing. The German occupation in World War I did not see the work suspended, because the occupying power saw the strategic value of this important link, and so the entire length of the Canal du Centre was finally opened for traffic in August 1917.
In 1957 it was decided to upgrade the entire Canal du Centre to accommodate vessels of up to 1350t, and a new section was dug from Mons to Havré. This meant that the stretch of 300t canal that is the subject of the present nomination became redundant. Consideration was first given to various solutions for the stretch that was going out of commercial use, ranging from complete obliteration by demolition and filling to various partial forms of conservation. Financial constraints favoured its retention in its entirety, and a major public relations campaign led to the stretch of canal now proposed for inclusion on the World Heritage List being maintained in operation for recreational purposes. The project received many awards and prizes in the 1980s and 1990s.
